Abstracts

Dr Uwe Raffalski (IRF-K), Odin’s future: STEAM ? - A new Swedish Satellite for the Investigation of Earth’s Atmosphere.

The Odin satellite was launched on 20 Feb 2001 into a near polar orbit and is fully operational since. On 15 orbits a day measurements of a large number of trace gas constituents between 8 and 100 km are performed covering the latitude range 82°S to 82°N (in atmospheric mode). In astronomical mode it studies the physics and the chemistry of the interstellar medium by observing emission from key species. Odin is a Swedish-led mission in co-operation with Canada, Finland and France using sub-mm spectroscopy for astronomical and atmospheric studies. This is the first time sub-mm frequencies have been used from space for such studies. Earlier instruments such as the MLS instrument on NASA\'s Upper Atmosphere Research Satellite (UARS) and the MAS instrument on the Space Shuttle operated at mm-wave frequencies which limits their sensitivity and height resolution for a given antenna size. In addition to the Sub-mm Radiometer (SMR), an Optical Spectrometer and Infrared Imaging System (OSIRIS) is included in the payload to complement and enhance the atmospheric studies. OSIRIS is one of the first limb viewing spectrometers operating in scattered light.

The status of Odin is better than ever. However, even Odin will eventually die and new projects are coming up all the time. In 2002 the Swedish National Space Board sent out a call for ideas for future satellites and space missions. This led to a project called STEAM (stratosphere-troposphere exchange and monitoring), which received highest priority at SNSB. If this project gets funding this satellite will proceed the monitoring tasks of Odin. But it will also address scientific questions like the exchange of gases between the upper troposphere lower stratosphere region. Most important will be the water vapor transport which has significant importance on the future climate.

In my talk I will present the achievements with Odin as well as the ideas that make STEAM such an interesting project for the Swedish space activities.

Dr Georgy Zastenker (Space Research Institute, Moscow), Review of some new solar wind features investigated by Interball project.

Some new features of the solar wind were found in the INTERBALL project by comparison of the multipoint observations and using high-resolution plasma measurements onboard INTERBALL-1/MAGION-4 satellites. These results allow us to suggest some new concepts about solar wind in several points, namely:
- dimensions and persistent time of the middle-scale structures,
- large and very sharp plasma density changes on the borders of the small-scale structures,
- significant inclinations of many sharp plasma phase fronts,
- geoeffectivity of the sharp changes of the plasma dynamic pressure,
- not only magnetic field but also plasma in phase fast variations in the foreshock,
- large amplitude, low and high frequency plasma and magnetic field variations in the magnetosheath; their origin, dependence on IMF direction and comparison with MHD models.

Dr Edmond Murad (Emeritus, Space Weather Center of Excellence, Air Force Research Laboratory, Hanscom AFB, MA, USA), Melting and Evaporation of Meteoroids.

Meteors are by definition transitory phenomena arising from the entry of meteoroids in the Earth’s atmosphere. The meteoroids are small particles generally arising from the dust released by comets as they near perihelion. The dust, for the most part consists of silicates, some organic matter, and some water; the dust is released into a very cold environment (< 100 K), even though the temperature of the comet nucleus at perihelion may be as high as 330 K. As the orbit of the dust cloud intersects that of Earth, some of the dust is captured by Earth. The captured dust begins its fiery descent into Earth’s atmosphere, giving rise to the shooting star phenomenon. The shooting star phenomenon indicates that the temperature of the meteoroid is quite high – somewhat resembling an incandescent lamp. At that point most of the meteoroid material is evaporated. Between the point of capture and early descent into the atmosphere (say ~ 200 km) and the evaporation (when the meteoroid is incandescent) of the metals, a complex set of chemical processes occurs, despite the short transit time. I will talk during this seminar about phase transitions undergone by the dust material, eventual melting, and evaporation (or sublimation of the metals). I will briefly discuss how fractionation and possible formation of eutectic mixtures might affect the observed metallic species.

Dr Masatoshi Yamauchi (IRF-K), Wedge-like structured sub-keV ions inside the ring current region.

Structured dispersive sub-keV ions inside the ring current region (L=3 to 10), so called wedge-like dispersions, are surveyed using Viking, Freja, Munin, and Cluster satellites.
(1) What is the signatue, and why they are interesting (to me)?
(2) Patterns classification and statistics.
(3) Comparison to past simulation (based on long-time drift by ExB and grad-B drifts).
(4) correlation to the geomagnetic activity (past 12 hours).
(5) problems/puzzles (identification, composition, LT distribution,
substorm relation).

Prof. Rickard Lundin (IRF-K), Solar wind removal of volatiles from celestial objects - perspectives on the Mars Express- and Rosetta missions.

The Mars-Express and the upcoming Rosetta-missions are two important ESA-missions with major IRF involvement, scientifically as well as technically. A key science objective for both missions is to understand the evolution of celestial bodies in the solar system, in particular the question about source and loss mechanisms for volatiles. The solar wind interaction with the atmosphere/ionosphere of the Earth-like planets and comets represents an important loss process. The Earth-like planets, orbiting close to the Sun, are subject to a continued forcing by solar radiation - electromagnetic as well as corpuscular. Comets are in a similar manner subject to strong forcing during their perihelion passes. The solar forcing leads to escape of matter from the celestial objects by thermal (Jeans) escape and non-thermal (plasma) escape processes. The visible evidence for the erosion of matter from a comet is the long tail, specifically the plasma tail (ion tail). Thermal and non-thermal escape are both important, but non-thermal escape is more efficient as a loss process.
ASPERA on Mars Express will address new aspects of the non-thermal escape processes (ENA-imaging) but it will also enable a follow-up of our Phobos-2 findings on the \"planetary wind\" (plasma escape) from 1989. Moreover, ASPERA may or may not corroborate some controversial findings obtained from Phobos-2 (e.g. dusty plasma).
On board the Rosetta space probe, scheduled for launch on 26 Feb 2004, we have two IRF instruments, ICA (ion composition analyzer) and LAP (Langmuir probe), with the prime objective to study the solar wind interaction with comet 67P/Churyonov-Gerasimenko.
The escape of matter from a celestial body by non-thermal escape can be modelled from relatively simple energy and momentum considerations. We use Mars and 67P/Churyonov-Gerasimenko as typical targets for the solar wind energy and momentum exchange and compute the model escape of volatiles as a consequence of this interaction. The results from the model is interesting, indicating that solar wind erosion is sufficient in explaining the major erosion from non-magnetized objects in the inner solar system.

Key words: Solar wind, the atmosphere of planets and comets, plasma escape

Dr Alexander Kozlovsky (Sodankyla Geophysical Observatory, Finland), Response of Dayside Auroras and Ionospheric Plasma Flows to a Solar Wind Pressure Pulse.

Global ultraviolet auroral images from the IMAGE satellite are used to investigate the response of the dayside auroral oval to a sudden impulse (SI) in the solar wind pressure. The observations are supplemented by the TV all-sky camera images over Svalbard in the pre-non sector. We show that after the SI, new discrete auroral forms appear in the poleward part of the auroral oval so that the middle of the dayside oval moves poleward from about 70 to about 73 deg. AACGM latitude. This poleward shift started in the 15 MLT sector, then similar shift was observed in the MLT sectors located more westerly, and eventually the shift was seen in the 6 MLT sector. Thus, the auroral disturbance \"propagates\" westward (from 15 MLT to 6 MLT) at an apparent speed of the order of 7 km/s. We show that the above auroral disturbances are associated with the westward propagating convection vortex as inferred from the global convection maps produced by the SuperDARN HF radars. The poleward boundary of the auroral oval did not show any prominent motion associated with the SI. The optical and radar observations can be interpreted in terms of the pressure disturbance propagation through the magnetosphere at a velocity of the order of 200 km/s that is essentially slower than a magnetosonic (fast Alfvén) wave, and generation of a potential (curl-free) electric field in the wake of the disturbance. We suggest that the interchange instability is a possible reason for the development of discrete dayside auroral forms after the SI. We discuss the reasons for the slow propagation speed of the disturbance and for a vortex-like convection pattern associated with the auroral motions.

Dr Vladimir Safargaleev (Apatity), The objectives and some preliminary results of EISCAT campaign on investigation of dayside auroras dynamics.

The EISCAT experiment on study the dayside auroras over Svalbard was performed on 19-27 January 2004. Participants: Swedish Institute of Space Physics, Kiruna, Sweden (H Nilsson, T Sergienko), Sodankylä Geophysical Observatory, Oulu University, Oulu, Finland (A Kozlovsky), Polar Geophysical Institute, Apatity, Russia (V Safargaleev). We used ESR-32m antenna (pointed to west at 45 deg. elevation) to measure the plasma flow along East-West, and mainland UHF radar was pointed to north at low elevation (20 deg.) to observe the North-South plasma flow. The auroral activity was monitored by the PGI TV camera in Barentsburg and the FMI ASC camera in Longyearbyen. The data of the PGI induction magnetometer allowing the registration of magnetic field variations in the range of 0.1 ˆ 20 Hz were also available. Three intervals of auroral activity will be discussed: an auroral \"torch\" formation, the poleward displacement of auroras after IMF Bz turning northward and the PMAF event accompanying with electron density enhancement in EISCAT data and \"pearl\" type magnetic pulsations in magnetometer data. The possible interpretation will be suggested.

Dr Evgenia Belova (IRF-K), Polar Mesosphere Summer Echoes and ionospheric heating: results and future plans.

Polar mesosphere summer echoes (PMSE) are very strong radar returns that occur during summer months near the mesopause at high latitudes. They were discovered about 20 years ago. It seems that PMSE reflect complicated processes occurring in a multi-component plasma consisting of electrons, ions and charged aerosols and interaction between ionized and neutral atmospheric components. So far there is no clear and complete understanding the mechanism of PMSE. In order to influence the electron component during PMSE events, we conducted, in the summers of 1999, 2001, 2002 and 2003, joint PMSE/Heating experiments using the EISCAT VHF radar and the EISCAT Heating facility.
I will give a review of these PMSE and ionospheric heating experiments. Obtained results will be discussed and future plans will be presented.

Dr Yasuhide Hobara (IRF-K), High Altitude Oxygen Outflow Observed by Cluster Satellites: Energization and Subsequent Wave Activities (Preliminary Results)

Cluster spacecrafts observe high altitude ion outflow events rather frequently. In this report, we concentrate on one ion outflow event with a significant energization of oxygen ions in concert with Broad-band ELF emissions in April 2001 to study the relationship between high-altitude heavy ion energization and subsequent wave activities.
The outflow events are observed by two S/Cs for which CIS-CODIF measurements are available at high altitude polar cap region around 7.5 Re. The separation distances between the S/Cs are a few hundreds km. The energy spectrogram of oxygen ions shows an increase of their energies up to a few tens of keV from hundreds of eV within 30 seconds and wave equipments (EFW and STAFF) detect enhanced wave activities in the ULF/ELF range. During this event, hydrogen ions do not show the meaningful heating. Comparative analysis of temporal variations between particle characteristics (distributions, temperature, moments, energy flux etc) and wave properties (such as wave normal angle, polarization, and Poynting flux calculation) for three S/Cs will be performed to investigate the source mechanism and spatio-temporal characteristics of the oxygen ions and subsequent wave activities.

Dr Herbert Gunell (IRF-K), Solar wind charge exchange at Mars.

Wherever the solar wind meets a neutral atmosphere, X-rays are emitted by a charge exchange process between the neutrals and heavy solar wind ions.

A hybrid simulation of the solar wind-Mars interaction and a test particle simulation of heavy ion trajectories near Mars is used to compute the contribution from charge exchange processes to the X-ray emission from Mars. The results are compared to observations of X-rays from Mars made with the Chandra telescope (Dennerl, K., Astronomy & Astrophysics, vol. 394, pp. 1119-1128, 2002). The comparison indicates that the solar wind charge exchange process is a likely candidate for the production of the X-ray halo at Mars.

The calculations were performed in three steps. First the solar wind parameters were estimated from data obtained by the WIND spacecraft. Since Mars was near opposition the plasma that was sampled by WIND near the earth on 2 July 2001 arrived at Mars two days later during the X-ray observation. The data was scaled with the distance from the sun, and the average parameter values over the period of the observation were used as input parameters for a hybrid simulation.

The second step was running a hybrid simulation of the interaction between the solar wind and Mars to obtain the electric and magnetic fields around Mars.

As a third step a test particle simulation was run, calculating the trajectories of heavy solar wind ions in the electric and magnetic fields that were obtained from the hybrid simulation. The X-ray emission density was saved on a grid for each time step of the test particle simulation. A hundred thousand trajectories were calculated for each of ion species.

Sachiko Joko (IRF-K), The relations between geomagnetic activities and O+ outflows observed in the dayside magnetospheric polar region by Cluster/CIS (reversion of ICS-7 presentation).

The terrestrial-origin O+ ions outflowing in the dayside
high-altitude (from 3Re up to 11Re)/-latitude (from 70 to 90
degrees in invariant latitude, ILAT) polar region have been
observed by the CIS instrument onboard the Cluster satellite.
The statistics of polar outflowing O+ ions ((1) energy of max
number flux, (2) max number flux, and (3) number density) is
complied in terms of geomagnetic activities represented by
Kp index for global/planetary geomagnetic activity and ASY/SYM
indices for mid-latitude geomagnetic disturbances (instead of
AE and Dst).
It seems that O+ ions outflowing in the polar region respond
well to ASY/SYM indices rather than to Kp on (2) and (3)
according to on-going study.

Grigory Nikulin (IRF-K), The Mean Meridional Circulation and Wintertime Ozone Buildup in Midlatitudes.

Vertical residual velocities calculated from the quasigeostrophic
transformed Eulerian mean thermodynamic and continuity equations are used to study connections between the residual mean circulation of the stratosphere and wintertime midlatitude ozone buildup. We found agreement with theoretical considerations for November, January and February while there are no expected connections in December. Difference between months may be explained by stronger contributions from other processes (meridional mixing, chemistry) than the residual mean circulation.

Also I will explain theoretical background for calculations of mean meridional velocities.

Tues. 2 September

Prof. Amos Zemel (Ben Gurion University of the Negev, Israel), Innovative Renewable Energy Research in Israel: From Large Scale to Small Scale and Back. [Abstract]

11 September

Prof. Dr Ingrid Mann (Institut für Planetologie, Westfälische Wilhelms-Universität, Germany), The Heliosphere and the Meteoritic Complex. [Abstract]

18 September

Prof. Bengt Hultqvist (IRF-K), Downward Accelerated Ions: Acceleration Mechanism and Ion Source. [Abstract]

25 September

Prof. Rickard Lundin (IRF-K), Plasma in the magnetospheric boundary layers: Frozen in - or not? [Abstract]

2 October

Magnus Emanuelsson (IRF-K), Strålningstest av OpAmpar. [Abstract]

Mon. 13 October, 10 am (Aula)

Dr Evgenia Belova (IRF-K), How and why we heat the ionosphere. (Docent lecture)

16 October, 10-12 (Aula)

Spatial Modelling Centre (SMC), Umeå University: Presentation of the database ASTRID, the micro-simulation model SVERIGE, and related projects. [Abstract]

23 October

Dr Mats Holmström (IRF-K), Monte Carlo simulations of planetary ions and neutrals at Mercury. [Abstract]

30 October

Grigory Nikulin (PhD student, IRF-K), Influence of early winter wave activity on midwinter circulation in the stratosphere and troposphere. [Abstract]

6 November

Dr Yasuhide Hobara (postdoc, IRF-K), Extremely low frequency radiation and ionospheric disturbances in association with transient luminous events in the mesosphere. [Abstract]

13 November

Dr Peter Dalin (IRF-K), The comparison of Danish and Moscow NLC observations: statistical results. [Abstract]

20 November

Dr Hans Nilsson (IRF-K), Radar Observations in the Vicinity of Pre-noon Auroral Arcs. [Abstract]

4 December (Aula)

Walter Allvin (Zero Group) presents Xero and the Zero Group\'s activities (in the Aula): www.xero.se

11 December

Dr Tima Sergienko (IRF-K), The lateral spread of proton precipitation: A comparison between incoherent scatter radar observations and model. [Abstract]

16 January

Sven Bugarski (University of Heidelberg), Methods and Problems of BrO DOAS Analysis. [Abstract]

7 February

Mats André (IRF Uppsala), Layers at ion and electron scales in the high-latitude magnetopause.

11 February

Dr Takumi Abe and Dr Takeshi Imamura (Japan), Japanese Venus Climate Orbiter.

13 February

Evgenia Belova (IRF-K), A Study of Polar Mesosphere Summer/Winter Echoes with the EISCAT VHF Radar. [Abstract]

20 February

Vladimir Safargaleev (Polar Geophysical Institute, Apatity, Russia), High-latitude dayside Pc1 events as indicator of reconnection. [Abstract]

27 February

Rickard Lundin (IRF-K), The Wakes and Magnetotails of Venus and Mars. [Abstract]

13 March

Grigory Nikulin (IRF-K), Dynamical contributions to the total ozone trends in the Northern Hemisphere midlatitude. [Abstract]

20 March, 1 p.m.

Sheila Kirkwood (IRF-K), Dust in the mesosphere - is it really there and why should we care? [Abstract]

27 March

Susanne Roslin (Umeå University), Adsorbtion of CFC on Carboxen during sampling in the stratosphere. [Abstract]

3 April

Peter Dalin (IRF-K), The observation of gravity waves in Noctilucent Clouds. [Abstract]

10 April, 1 p.m.

Asta Pellinen-Wannberg (IRF-K), The EISCAT meteor method: a review and recent results. [Abstract]

Tues. 22 April, 10 a.m.

Hans Nilsson (IRF-K), Cluster multi-point observations of ion outflow. [Abstract]

8 May

No seminar (Rymdforum 03 conference in Kiruna)

15 May

Csilla Szasz and Johan Kero (IRF-K), A Solar Active Region Quasi-Biennial Fluctuation. [Abstract]

22 May

Sachiko Joko (IRF-K), Ion velocity distributions at higher altitudes observed by CIS/Cluster: Formation of shell-like distribution as observed in cometary pick-up ions? [Abstract]

5 June

Jane Zheng-Johansson (IOFPR, Nyköping), Unification Scheme for Classical and Quantum Mechanics at All Velocities. [Abstract]

12 June

Herbert Gunell (IRF-K), Simulated ENA images of the Venus-solar wind interaction region. [Abstract]

19 June

Tima Sergienko (IRF-K), Quenching rates of O(1D) in the upper thermosphere. [Abstract]

ABSTRACTS

\"Methods and problems of BrO DOAS analysis\", Sven Bugarski (IRF-K)

The focus of the seminar will be the DOAS (Differential Optical Absorption Spectroscopy) measurements from the University of Heidelberg at IRF. I will briefly describe the involved instruments, explain the methods to calculate SCDs (slant column densities) of trace gases and discuss problems, results and aims of my work.

\"A Study of Polar Mesosphere Summer/Winter Echoes with the EISCAT VHF Radar\", Evgenia Belova (IRF-K)

I will tell about use of EISCAT VHF radar in studies of mesospheric layers which occur in summer and winter time. My report is based on the presentations given on the last COSPAR conference in Houston, USA in October 2002. The abstracts of these presentations are below:

STUDY OF POLAR MESOSPHERE WINTER ECHOES DURING SOLAR PROTON EVENTS WITH THE EISCAT VHF RADAR

E. Belova (1), S. Kirkwood (1), M. Rietveld (2, 3), I. Häggström (3)
(1) Swedish Institute of Space Physics, Kiruna, (2) EISCAT Scientific Association, Kiruna, (3) Max-Planck-Institut für Aeronomie, Katlenburg-Lindau

Recently, Kirkwood et al. (2002) reported detecting enhanced MST radar echoes from mesospheric altitudes in the winter period during Solar Proton Events (SPEs). It was proposed to refer to them as Polar Mesosphere Winter Echoes (PMWE). They showed characteristics from which one can conclude that aerosols are most likely involved in generation of the radar echoes, in the same way as for PMSE. It was also found that there is no direct dependence of PMWE occurrence on electron density (calculated using ionospheric modelling). However PMWE occurrence correlates well with low values of l (the ratio of negative ion density to electron density, derived also from the model). Our aim is to check these results by applying a new EISCAT D-layer program during PMWE events. On November 5 and 23, 2001 two strong SPEs occurred. The ESRAD 52 MHz MST radar detected enhanced backscatter from 65-75 km altitude. The EISCAT VHF radar was running the D-layer Common Program. We use electron density profiles derived from incoherent backscattered power to interpolate electron density at the PMWE altitudes. The relationship we obtain between PMWE power and electron density will be presented and discussed.

RELATION BETWEEN POLAR MESOSPHERE SUMMER ECHO POWER AND ELECTRON DENSITY AS MEASURED WITH THE EISCAT VHF RADAR

E.Belova (1), I. Häggström (2), P. Chilson (3), S. Kirkwood (1)
(1) Swedish Institute of Space Physics, Kiruna, (2) EISCAT Scientific Association, (3) Cooperative Institute for Research in Environmental Sciences, University of Colorado, and NOAA Environmental Technology Laboratory, Boulder

Strongly enhanced radar echoes from the polar summer mesopause (PMSE) are an indicator of the complex processes occurring in this important region. They reflect coupling between neutral and ionised atmospheric components, the latter including electrons, ions and charged aerosols. The dependence of PMSE power on background electron density has been discussed in several papers. Electron density values used for such studies have been derived from model simulations, or proxies such as riometer data have been used to estimate electron density at mesospheric altitudes. Reliable rocket measurements of electron density are available only for a small number of cases. They are not sufficient to make a firm conclusion either on the dependence of PMSE power on electron density or on electron density limits for the existence of these strong echoes. The latter may be crucial for testing existing PMSE theories. We propose to use a new D-layer EISCAT Common Program (CP) for deriving electron density and other ionospheric parameters just below and above the layers with abnormally enhanced power. Values of background electron density at altitudes of PMSE can be calculated using interpolation. In summer 2002 a PMSE experiment will be conducted in Northern Norway using the EISCAT VHF radar. It will be run in 2 modes: the D-layer CP and Special Program (SP). The SP is designed to detect and to measure PMSE power. By running the D-layer program for 24 hours we expect to cover a wide range of electron density values. The first results of this experiment will be presented. The relationship we obtain between PMSE power and electron density will be discussed.

[TOP]

\"High-latitude dayside Pc1 events as indicator of reconnection\", Vladimir Safargaleev (Polar Geophysical Institute, Apatity, Russia)

The data of induction magnetometer installed at Barentsburg observatory in Spitsbergen archipelago are analyzed in combination with the data of two other magnetometers located on Scandinavian and Kola Peninsulas. We considered the intervals of very large negative IMF Bz when the cusp is assumed to be shifted at large distance south of its statistical position and Spitsbergen turns out in the polar cup.

Altogether, eight intervals were considered. In all cases the DMSP data indicated that Barentsburg observatory was in the polar cap, whereas the location of two others might be associated with either cusp or llbl or bps projections. The magnetic pulsations of Pc1 frequency range were observed around the local noon and in the polar cap only. They had a form of several short-living bursts and lasted for 5 - 15 minutes. In the cases when the CUTLASS data were available, the interval of Pc1 activity coincided well with the appearance and decay of fast ionospheric convection flow channel. We think that these pulsations are originated from the magnetosheath (namely, from the plasma depletion layer) where the plasma is anisotropic and undergoes the IC-instability. Due to impulsive reconnection, the unstable plasma turns out on the magnetic field lines connected with the Earth\'s ionosphere and IC-waves may be seen on the ground as the bursts of Pc1.

\"The Wakes and Magnetotails of Venus and Mars\", Rickard Lundin (IRF-K)

R. Lundin and S. Barabash

The solar wind interaction with the weakly magnetized Venus and Mars differs from the solar wind interaction with the Earth and other strongly magnetized planets in our solar system. A significant difference between magnetized and unmagnetized planets is the stand-off distance to the solar wind, the solar wind impacting directly on the topside atmosphere of nonmagnetized planets, whilst a strongly magnetized planet fends off the solar wind well above the atmosphere. In fact, neglecting the difference in gravitational pull, there are many similarities between Mars, Venus and comets in terms of their interaction with the solar wind. However, for the nightside tail region the difference between magnetized and nonmagnetized celestial objects are less marked. Nonmagnetized celestial objects with an atmosphere have, like magnetized objects a magnetotail induced by their interaction with the solar wind.

In this report we review the magnetotails of Mars and Venus and compare with the observational/ visible characteristics of comets. Besides their overall morphology and the general atmospheric outflow/erosion, we also consider the filamentation of ionospheric plasma ejected into the magnetotail from non-magnetized as well as magnetized bodies in the inner part of the solar system.

\"Dynamical contributions to the total ozone trends in the Northern Hemisphere midlatitude\", Grigory Nikulin (IRF-K)

During last years more and more evidences showing importance of

dynamic processes for the total ozone decline have been presented. A

separation of chemical and dynamical contributions to total ozone

variability is the significant question for understanding of the ozone

changes. Several recent studies have shown that a substantial part of

year to year winter-spring total ozone variations in the Northern

Hemisphere (NH) middle and polar latitudes are influenced by dynamic

factors. Wave activity in the lower stratosphere and different indices

of atmospheric circulation patterns are mostly used as dynamical

proxies. At the same time estimations of dynamical contributions in

the observed long term ozone trends are very different. Partly it

could be explained by different months and periods that have been

taken for investigations.

The multiple linear regression model describing evolution of the NH

midlatitude total ozone during February-May (1979-2001) has been

applied to estimate contributions of atmospheric circulation changes

to the observed long-term trends in total ozone. We use 4 predictors,

namely: the 100 hPa zonal mean heat flux, the Arctic Oscillation index,

the quasi-biennial oscillation and the 11-year solar cycle. The

regression accounts for 77% of the observed total ozone variance in

May, 83% in April, 77% in March, and 76% in February. There are no

significant trends in the model residuals from March to May. The

February residual trend is on the edge of statistical significance and

reduced by more than two times. The obtained results show that the

dynamic factors can play the primary role in the long-term changes of

the NH midlatitude total ozone.

\"Dust in the mesosphere - is it really there and why should we care ?\" Sheila Kirkwood (IRF-K)

There is a continual rain of extraterrestrial matter into our atmosphere. There are also increasing amounts of material sent up from the Earth\'s surface (space debris, rocket exhausts). There are theoretical grounds for expecting that this leads to a population of \'dust\' in the middle atmosphere, but this dust has not yet been proven to exist. If it does exist, it can have significant consequences for atmospheric composition by introducing heterogeneous chemical reactions. It is also of importance for the interpretation of remote sensing by optical methods - the usual assumption is that there is no dust so that dust layers will be interpreted as something else (e.g. extremely low temperatures or high water content).

In the last 3 years we have found radar echoes with ESRAD and EISCAT which seem to correspond to dust layers. The seminar will be a progress report on how we are building up evidence (using radar, lidar and rockets) that these echoes cannot be explained by anything else (such as turbulence).

\"Adsorbtion of CFC on Carboxen during sampling in the stratosphere,\" Susanne Roslin (Umeå University)

DESCARTES is a balloon-borne instrument for the measurement of long-lived trace

gases in the stratosphere. The principle behind the instrument is that by letting a

measured amount of volume pass through sample tubes containing the adsorbent

Carboxen, trace gases will be trapped inside the sample tube while the rest is passing

through. The instrument adsorb CFC-11, CFC-113, CCl4 and CH3CCl3 in measurable

quantities but is optimised for CFC-11.

The seminar will focus on the adsorption efficiency of the sample tubes. Preliminary

results of my study will be presented. Can quantitative adsorption of primary CFC-11

be secured during sampling with DESCARTES in the stratosphere?

[TOP]

\"The observation of gravity waves in Noctilucent Clouds.\" Peter Dalin (IRF-K)

We have considered one case of observation of gravity wave in the NLC observed above Sweden. Visual observations supplement substantially to radar measurements (Esrange and Andenes) with the finding of small and medium-scale of gravity waves and may be very useful in the analysis of their dynamics even the NLC being observed from one point. In the examined case both optical and radar observations revealed a gravity wave with approximately the same characteristics propagating from south-east to north-west direction. This direction coincides with what was found by Vincent and Fritts (1987) for medium-period waves in summer season.

\"The EISCAT meteor method: a review and recent results\", Asta Pellinen-Wannberg (IRF-K)

The most important stages of development of the High Power Large Aperture (HPLA) radar method for meteor observations is presented from the European Incoherent Scatter (EISCAT) Facility point of view. The strength of EISCAT for this application is its high latitudinal location, dual frequency and tristatic observation possibilities. Meteoroid vector velocities can be derived from the tristatic observations. At EISCAT they average at about 65 km/s, which can be related to large cross sections for collisional ionization in hyperthermal collisions. Recent very high resolution observations simultaneously from three directions show processes occurring as some meteoroids pass through the radar beam. Finally, intensive shower meteor input during 2002 Leonids is related to ordinary ionospheric incoherent scatter observations.

\"Cluster multi-point observations of ion outflow\", Hans Nilsson (IRF-K)

A case study of oxygen ion energization and outflow is presented. The data

show oxygen ions being energized to energies of up to 40 keV, the upper

energy limit for the CLUSTER CIS ion spectrometer. The most important finding

is that the energization appear to be isotropic at high altitude, in contrast

to lower altitude energization which is typically transverse to the magnetic

field.

Furthermore the multi-spacecraft configuration is used to analyze the observed

structures in detail. It is discussed what we can expect to observe for

different situations, and this is compared with actual observations. In

particluar a mesoscale event of strong heating and associated outflow appears

to show a temporal decay which is similar for the two observing spacecrafts.

This indicate that both spacecrafts were situated in a coherent region where

all field-lines had a similar history, as could for example be expected in

the flux bundle expected from a flux transfer event.

\"A Solar Active Region Quasi-Biennial Fluctuation\", Csilla Szasz and Johan Kero (IRF-K)

A quasi-biennial fluctuation has been detected in the time-series of the sunspot umbra/penumbra area ratio (U/P) on the basis of the Debrecen Photoheliographic Data. The study is based on an intermittent period of nearly eight years; the material comprises more than 18.000 individual sunspots.

In the seminar we will present information about the temporal behaviour of the U/P ratio, period analysis and umbral area dependence. The physical background of the phenomenon is yet unclear but it seems to belong to the growing family of mid-term fluctuations.

\"Ion velocity distributions at higher altitudes observed by CIS/Cluster: Formation of shell-like distribution as observed in cometary pick-up ions?\" Sachiko Joko (IRF-K)

During the years of 1986 and 1987, after exploring comet Giacobini-Zinner and comet Halley, a lot of observations and theoretical studies by means of computer simulation on cometary newborn \'pick-up\' ions and their behaviours have been reported. Cometary newborn ions picked up by the solar wind are known to form shell-like configuration in velocity phase space at ralatively far upstream of the nuclei of comets, in which particle density is small enough to be collisionless and so that linear theory of electro-magnetic instabilities is considered to be applicable. By means of observations by the CIS instrument onboard the Cluster satellite, at the dayside magnetosphere, supposed to be in the poleward cusp or the mantle region with above 8 Re (Earth radii) in altitude, shell-like configuration in velocity distribution of O+ ions has been found (We believe so at this moment). In this seminar, I\'ll just present how the shell-like velocity distribution looks like and how related electro-static and electromagnetic data seem to be as the first stage of this study.

\"Unification Scheme for Classical and Quantum Mechanics at All Velocities\", Jane Zheng-Johansson (IOFPR, Nyköping)

I first review the whereabouts, especially the unsolved problems in my opinion, in the issues of physics relevant to here, including the interpretation of Schrötdinger\'s wave function, the nature of inertial mass, space and time, the picture of elementary particles in qft and in string theory, and the unification schemes, etc.

I then introduce our recently achieved result, The Unification of Classical and Quantum Mechanics. Our approach is to firstly derive a realistic submicroscopic model for vacuum (of a Dirac kind) based on overall experimental observations, establish Newtonian equation of motion of it under external perturbation, and solve. The solution and predictions are presented in two parts. (I) The fundamental formation of martial particles: Our solution shows that, a basic particle, which may be e.g. an electron, is composed of a tiny free aether-pole (a bare charge) and the mechanical wave disturbancesidentifying with electromagnetic wavesgenerated by it in the medium. When in motion, of velocity v (here (v/c)-->0), as a result of a first kind source effect this particle wave exhibits all of wave and dynamic properties known for a de Broglie wave, and is here called a Newton- de Broglie (NdB) particle wave. In a confined space, the Newtonian solution for the NdB particle wave is equivalent to that given by Schrödinger\'s quantum mechanics. Through this general scheme for particle formation we have accomplished a basic task of the unification of classical- and the quantum- mechanics, both in terms of the deduction of the latter from the former, and the convergence of the latter into the former at high velocities. And we unfold the origins of a series of phenomena including the electromagnetic waves, the electromagnetic radiation and absorption, atomic and thermal excitations, the inertial mass, the Schrödinger\'s wavefunction and de Broglie wave, the Heisenberg\'s uncertainty relation, the de Broglie relations, the simultaneous existence of electron and positron or generally of particles and their anti-particles, the (rest) mass-energy equivalence relation, etc. (II) The Theory of Relative motion: (A) we show that the (v/c)^2-dependent terms yield in the particle wave and dynamic quantities a second kind source motion effect (SSME). The SSME augments the particle mass, and the wavevector and frequency of the particle\'s constituent waves, etc., by a factor \\g = 1/\\sqrt{1-v^2/c^2} in the v-direction; and conversely for the reciprocal quantities. Subsequently a moving body comprising the so affected particles will present a simultaneous length and time contractions (of Lorentz-Fitzgerald kind) as measured in the frame attached to the body. (B) A systematic survey of pivotal experimental indications leads us to conclude that the light velocities, c measured in vacuum and c\' measured by a moving observer, and the observer\'s v obey the common triangle law of vector addition, conforming to the Galilean transformation (GT). (C) Combining (A) and (B) yields a set of transformation equations between an inertial reference frame at rest (in vacuum) and one moving relative to it, called Galilean-Lorentz transformation (GLT). The GLT together with the underlying theoretical basis of the general scheme yields a consistent Theory of Relative Motion. With the theory, we predict the observational null-/constant- fringe shift result of the Michelson-Morley/Kennedy-Thorndike experiment, the Doppler effects of electromagnetic waves, the equivalence principle of Newton\'s laws of motion in all inertial frames, etc, and we extend the classical and quantum mechanics to (v/c)^2 >>0. The complete agreement is in turn a justification of the general scheme.

Finally, I outline the on-going and planned research problems within our unification projects, these including the derivation of Schrödinger\'s equations from Newton mechanics, the formulations of a microscopic theory of gravity, and a theory of relative motion in non-inertial frames, and a treaty of cosmological problems.

\"Simulated ENA images of the Venus-solar wind interaction region\", Herbert Gunell (IRF-K)

We present simulated images of energetic neutral atoms (ENAs) produced in charge exchange collisions between solar wind protons and neutral atoms in the exosphere of Venus.

The ENA images are generated through the integration of the ENA production along lines of sight to a virtual ENA instrument. A model, that is based on measurements, of the neutral gas density in Venus\' upper atmosphere is used in combination with a model of the plasma flow around Venus. The plasma model is a semi-analytical MHD model developed by Helfried Biernat and Nikolai Erkaev.

The images are found to be dominated by two local maxima. One produced by charge exchange collisions in the solar wind, upstream of the bow shock, and the other close to the dayside ionopause. The simulated ENA fluxes at Venus are lower than those obtained in similar simulations of ENA images at Mars.

\"Quenching rates of O(1D) in the upper thermosphere\", Tima Sergienko (IRF-K)

The 6300Å (red line) originated from the metastable O(1D) state is extensively used in the optical remote sensing of the upper atmosphere. The radiative lifetime of the 1D sate is rather long (~110 sec) and collision quenching by atmospheric gases is significant loss process for this state. Therefore the quenching rate coefficients are crucial in determining the 6300Å emission. While rate coefficients for quenching by N2 obtained in laboratory measurements and deduced from aeronomical observations are in good agreement, the importance of quenching by atomic oxygen is still under debate. Multipoint Auroral Large Imaging System (ALIS) measurements of enhanced 6300Å airglow caused by HF pumping in the ionosphere from the EISCAT-Heating facility were used to determine the effective lifetime of O(1D) state in altitude range of 200-300 km. The quenching rate coefficients obtained from the altitude dependence of the O(1D) lifetime are discussed.

3 October

Carl-Fredrik Enell (IRF-K), Optical Studies of Stratospheric Clouds. [Abstract]

17 October

Narayana Rao (IRF-K), UTLS Ozone Variations over Northern Europe. [Abstract]

24 October

Johan Arvelius (IRF-K), The Problem of Identifying Tropopause Folds in Ozone Soundings Avoiding Seasonal Biases. [Abstract]

14 November

Peter Dalin (IRF-K), An Estimation of Inertio-Gravity Wave Parameters in Noctilucent Clouds. [Abstract]

21 November

Sachiko Joko (IRF-K), Ionospheric Ions Outflowing at High Altitudes in the Dayside Magnetosphere. [Abstract]

Tuesday 26 November

Rickard Lundin (IRF-K), Ponderomotive Forces in the Magnetosphere. [Abstract]

5 December

Herbert Gunell (IRF-K), Beam-Plasma Interaction. [Abstract]

12 December (10-10.30)

Professor Liu (Center for Space Science and Applied Research, China), A Brief Introduction to the Chinese Double Star Project.

12 December (10.30-11)

Dr Li (Center for Space Science and Applied Research, China), The Plasma Sheet Oscillation and Compressional Pc5 Pulsations in the Magnetotail.

12 December (11-11.30)

Pontus C:son Brandt (Applied Physics Laboratory, USA), Usefulness of ENA Imaging for Magnetospheric Research: New IMAGE Results.

19 December

Khaled Fadel (IRF-K)

Friday 20 December

Gösta Gahm (Dept of Astronomy, Stockholm University), The Architecture of Interstellar Clouds.

ABSTRACTS

Optical Studies of Stratospheric Clouds, Carl-Fredrik Enell (IRF-K)

This seminar is a short summary of the methods used and developed in my PhD thesis, \"Optical studies of polar stratospheric clouds and related phenomena\". The principles of zenith-sky scattering and the use of bistatic imaging will be discussed and a few of the results discussed. It is shown that PSC presence can be detected, but probably underestimated, with zenith-looking photometers. A case study of PSCs by bistatic imaging shows changes on very short temporal and spatial scales.

UTLS Ozone Variations over Northern Europe, Narayana Rao (IRF-K)

There has been growing interest in the upper troposphere and lower stratosphere (UTLS) region in the atmospheric scientific community over the past few years for various reasons. They include concerns about increase in emissions, in particular NOx, from subsonic and supersonic aircrafts, which normally fly in this region and variations of ozone trends with height as well as spatial variations. Different 3-D global chemistry and transport models have estimated a NOx perturbation of 20-70% in the 8-12 km layer, causing an increase in O3 concentration by 2-9% through photochemical reactions. Observed trends in ozone shows interesting features with large decreases in the lower stratosphere at high and mid latitudes in both hemispheres, while the trends in the troposphere shows regional differences with a positive trend over Europe, a negative trend over Canada and no statistically significant trend over North America. However, most of the results on trends and seasonal variation of ozone are based on the data collected at mid-latitudes and Canadian Arctic stations. There are no reported reliable long-term measurement series of ozone in the European Arctic mainly because of the paucity of the long-term measurements of ozone. Most of our understanding on European Arctic ozone is based on results from a series of large campaigns, for instance EASOE, SESAME, THESEO, SOLVE, conducted in the European Arctic augmented by some other small campaigns. So in this talk, I will discuss about variations of ozone (annual as well as interannual) over northern Europe using a relatively long-term database of 7 years. I would also like to discuss the relation between ozone and potential vorticity. Further, I will present preliminary results on the climatology of tropopause folds at high latitudes.

The Problem of Identifying Tropopause Folds in Ozone Soundings Avoiding Seasonal Biases, Johan Arvelius (IRF-K)

A discussion forum on the easily-explained problem of looking for tropopause folds in ozone soundings avoiding seasonal biases. Hopefully the discussion will concern the problem of looking for similar structures in data with variable structure.

An Estimation of Inertio-Gravity Wave Parameters in Noctilucent Clouds, Peter Dalin (IRF-K)

The case study of the Noctilucent Cloud (NLC) appearance on August 10-11, 2000 is examined. The clear wave dynamics are observed and the inertio-gravity wave is supposed to be responsible for the observed modulation in the NLC field. With the Esrange MST Radar data and Andøya MF Radar data we have managed to find the inertio-gravity waves which propagate upward from the stratosphere to the NLC altitude and could be responsible for observed wave dynamics in the NLC.

Ionospheric ions outflowing at high altitudes in the dayside magnetosphere, Sachiko Joko (IRF-K)

At the last spring EGS assembly I presented a case study of the ionospheric ions, especially O+ ions in this case, outflowing at high altitudes (higher than 6 Re) in the dayside magnetosphere observed by CIS/Cluster. I have continued to study this case and in this seminar I present several additional issues including other cases. The case of \"12 April, 2001\" shows that O+ ions were continously accelerated/energized during the whole orbit from the duskside polar cap, the cusp and the magnetopause to the magnetosheath. But the acceleration/energization processes differed depending on the altitude. As for ion species differencies, O+ and H+ behaved in different ways, by which I mean that the influence of the acceleration/energization processes on each ion species seem to be different. In this seminar, if we have enough time left, Hans Nilsson will give a short talk on issues relevant to mine, based on his presentation at the last COSPAR congress.

Ponderomotive Forces in the Magnetosphere, Rickard Lundin (IRF-K)

We review the current state of the art in the study of ponderomotive forces caused by ULF electromagnetic waves in the terrestrial magnetosphere. This field of research has attracted considerable attention in recent years. Even though the literature on the subject is quite extensive, there are still challenging questions encountered in applying the concept of ponderomotive forces to analysis of concrete space phenomena. The review presents a brief but clear and rational account of the subject from the basics up to problems of interest to research workers in the field of space physics. The hydrodynamic, quasi-hydrodynamic and test-particle approaches are used for description of ponderomotive acceleration and redistribution of ions in the ionosphere-magnetosphere coupled system. Theoretical problems of the ponderomotive wave-particle interaction are discussed in the light of recent satellite investigations of the auroral acceleration processes. We conclude that the ponderomotive forces play an important role in the structures and dynamics of the magnetosphere.

Beam-Plasma Interaction, Herbert Gunell (IRF-K)

This seminar concerns the interaction between an electron beam and a

plasma. Laboratory experiments were conducted using two different

setups; one with an electric double layer and the other with a hot

cathode as the electron beam source.

In both experiments the it was found that the electrostatic waves

generated by the beam-plasma interaction can concentrate to a narrow

spike with a full width at half maximum that is on the order of one

wavelength.

The narrow electric field spike has been reproduced in a one-dimensional

electrostatic particle in cell simulation. The spike is formed

only when the interaction occurs in the plasma density gradient that

surrounds a double layer and exists in front of a hot cathode. The

electron beam is spread in velocity space as it passes the spike.

Based on a simplified fluid descriptions of eigenmodes of a plasma

diode with a density gradient the localisation of the spike, spatially

and in frequency, can be explained. The conclusion, that is proposed

here, is that the spike can be seen as a coupled system of two such

eigenmodes that receive their energy from the beam-plasma interaction.

4 February

\"Kan man höra norrskenet? Den naturvetenskapliga bakgrunden till ljudfenomen i samband med starka norrsken\". Seminar by Christer Jurén, IRF Kiruna.

14 March

\"Observations and Analysis of Artificial Aurora\". Seminar by Björn Gustavsson, National Institute of Polar Research, Tokyo, Japan.

21 March

\"Case Studies of the Dynamical Development of Polar Stratospheric Clouds Using Multistatic Imaging\". Seminar by Carl-Fredrik Enell, IRF Kiruna. [Abstract]

28 March

\"Locations of proton isotropic boundaries as measured by conjugate high-altitude and low-altitude satellites\". Seminar by Natalie Ganushkina, FMI. [Abstract]

9 April

\"Substorm results from Interball\" and a report from the substorm conference in Seattle by Ingrid Sandahl, IRF Kiruna.

11 April

\"Cluster high-altitude observations of ionospheric plasma outflow\". Seminar by Sachiko Joko, IRF Kiruna [Abstract]

18 April

\"Response of Polar Mesosphere Summer Echoes to Ionospheric Heating\". Seminar by Evgenia Belova, IRF Kiruna. [Abstract]

2 May

\"Trends in Moscow NLCs occurrence and brightness.\" Seminar by Petr Dalin, IRF Kiruna. [Abstract]

16 May

\"Aerosols, clouds and climate.\" Seminar by Johan Arvelius, IRF Kiruna. [Abstract]

21 May

\"Longtime DOAS observation of trace gases in Kiruna.\" Seminar by Thomas Wagner, Heidelberg, Germany.

30 May

\"Auroral radiation of Jupiter.\" Seminar by Anil Bhardwaj, Space Physics Laboratory, Vikram Sarabhai Space Centre, India.

31 May

\"Space Program of India.\" Seminar by Anil Bhardwaj, Space Physics Laboratory, Vikram Sarabhai Space Centre, India.

4 June

\"Fast volume rendering.\" Seminar by Mats Holmström, IRF Kiruna. [Abstract] NB: in the Aula.

7 June, 1.30 p.m.

\"Waves and Fluctuations in Non-Maxwellian Plasmas.\" Seminar by Herbert Gunell, Dept. of Physics and Astronomy, University of Iowa. [Abstract] NB: in the Aula.

ABSTRACTS

\"Case Studies of the Dynamical Development of Polar Stratospheric Clouds Using Multistatic Imaging\". Seminar by Carl-Fredrik Enell, IRF Kiruna.

The important role of polar stratospheric clouds (PSCs) in

stratospheric chemistry is firmly established. The formation of PSCs

is closely related to temperature, which is affected by wave activity

on different scales. PSC occurrence thus reflects radiative and/or

dynamical stratospheric temperature changes.

The most obvious indication of PSC presence is the visual observation

of mother-of-pearl clouds. We present case studies of the development

of visual PSCs undertaken by means of ground-based cameras. Our

observations show that the presence of mother-of-pearl clouds varies

on a scale smaller than that of typical mesoscale models.

The images are studied further in the context of the meteorological,

dynamical situation, and visibility conditions (solar elevation and

tropospheric cloudiness).

\"Locations of proton isotropic boundaries as measured by conjugate high-altitude and low-altitude satellites\". Seminar by Natalie Ganushkina, FMI.

Polar CAMMICE MICS data of proton pitch angle distributions with energies

of 31-80 keV for the period of 1997-1998 were analyzed to determine the locations where

anisotropic pitch angle distributions (perpendicular flux dominating) change to isotropic

distributions. We study this high-altitude isotropic distribution boundary

(IDB) in terms of its location in L-shell and MLT. Statistical results

showed that this boundary is located at lower L-shells on the nightside and

at higher L-shells on the dayside with most distant location at dawn. With

the increase of magnetic activity, the IDB positions shift towards lower

L-shells at all MLT. The locations of IDBs were also determined for

different storm phases. A superposed epoch analysis revealed that the

L-shells of the IDBs move to lower L-shells with decreasing Dst and to

higher L-shells during Dst recovery. Several events were selected during

which simultaneous observations in the same local time sector were

available from Polar at high altitudes and from DMSP at low altitudes. The

magnetic field mappings to find the relative locations of both spacecraft

were made using the Tsyganenko T01 model with the observed solar wind input

parameters. The mappings showed that Polar and DMSP were placed on nearly

the same field lines, which leads us to suggest that the Polar IDB and the

b2i boundary at DMSP are closely related, and that the mapping between high

and low altitudes can be made sufficiently accurately.

\"Cluster high-altitude observations of ionospheric plasma outflow\". Seminar by Sachiko Joko, IRF Kiruna.

With respect to ionospheric-origin O+ ions upflowing through the polar cap, cusp/cleft or mantle, and magneto-

sheath, observed by Cluster/CIS above 3-Re altitude, increase of parallel flow velocity seems to be fed

by increase of transverse energy, as shown also by the previous study of Lundin and Hultqvist (1989), but on the other hand, parallel flow velocity continues to increase by some other processes, like pressure gradient or inertial drift.

\"Response of Polar Mesosphere Summer Echoes to Ionospheric Heating\". Seminar by Evgenia Belova, IRF Kiruna.

Polar mesosphere summer echoes (PMSE) are abnormally strong radar returns

that occur during summer months near the mesopause at high latitudes. They

were discovered about 20 years ago. It seems that PMSE reflect complicated

processes occurring in a multi-component plasma consisting of electrons,

ions and charged aerosols, and so far there is no clear understanding of

the mechanism of PMSE. In order to influence the electron component during

PMSE events, we conducted, in summer 1999, a joint PMSE/Heating experiment

using the EISCAT VHF radar and the EISCAT Heating facility. During our

experiment we demonstrated that PMSE was indeed affected by the heating

pulses, with the back-scattered signal decreasing when the heater was on.

The response time was less than 2 seconds. (Chilson et al., 2000). We have

now analysed the backscattered powers for selected time intervals and

heights for different PMSE/heating experiments with the highest available

time resolution of 29.85 ms. We find that there is an upper limit for the

time which it takes for PMSE power to respond to switching the heater on or

off which is less than 30 ms. Such a rapid response of the PMSE allows us

to differentiate between mechanisms which could be responsible for the

heating effect on PMSE. We find that enhancment of electron diffusivity

during heating is unlikely to be able to account for so rapid a decrease of

radar backscattered power when the heater switches on. We suggest that

increase of the Debye length up to half a radar wavelength due to electron

heating in a presence of aerosols might explain the heating effect on PMSE.

The time constant for this process is expected to be in the 1 ms range.

Finally, we make a proposal for the next PMSE/heating experiment which is

planed to conduct in summer 2002.

\"Trends in Moscow NLCs occurrence and brightness.\" Seminar by Petr Dalin, IRF Kiruna.

NLCs near Moscow, Russia are observing in specially organized campaigns

every summer season from 1962 up to present time. During this period all

the observers have been following the same procedure of NLC registration

and accompanying comments, elaborated in 1962.

Some statistical results were obtained from the database. One of its

important advantages is an accurate accompanying meteorological information. It allowed to

separate the cases of NLC no-registration due to a break in observation or

due to a bad weather from the cases of real absence during a clear night.

Such separation proved to be substantial for obtaining of geophysical

significant statistical results for NLC parameters. Long-term behaviour of

seasonally averaged NLC parameters was studied. Most interesting results of

this investigation are decadal (about 10 years) variability, zero trend in

a NLC occurrence probability for a clear night and a positive trend in

seasonally accumulated NLCs brightness (normalized by the number of clear

nights). The difference between this result and well-known result of

M.Gadsden (1990) is discussed.

\"Aerosols, clouds and climate.\" Seminar by Johan Arvelius, IRF Kiruna.

I will present some of the contents from the course \"Aerosols, clouds and climate\" that I

participated in this winter. The contents was (luckily) not as broad as the

title indicated. It was rather about the climatic effects of antropogenic

aerosols both directly and indirectly from their impact on the cloud

formation processes. This large perspecive will be discussed as well as

the modifications to the Köhler theory of partly soluable aerosols and

gases as well as surfactants.

\"Fast volume rendering.\" Seminar by Mats Holmström, IRF Kiruna.

It is difficult to interpret observed energetic neutral atom (ENA)

images, since an image only depends indirectly on the quantities that

usually are of interest - the distribution of ions and neutrals.

For a detailed, quantitative, analysis of observed images one can use

inversion techniques to extract parameters from a mathematical model

of the ENA production. Basically, we generate images until we find

one that closely match the observed image. The parameters that

produce the best match is our parameter estimate. The sequence of

generated images is determined by the chosen minimization algorithm.

Thus, to solve the inverse problem, hundreds, or even thousands, of

images must be generated and it is crucial that we can generate each

image as fast as possible.

Computer imaging of volume emissions is a general problem, of which

ENA imaging is just a special case. In computer graphics this process

is denoted volume rendering. We have developed an hierarchical,

wavelet based, method for fast imaging of volume emissions. The

proposed method also provides error estimates and error control,

automatically. The approach is to find a sparse representation of the

volume emission, a three-dimensional function, before the projection

onto the image plane. The representation is based on conservative

subdivision. Numerical experiments suggest that the proposed method

can be orders of magnitude faster than traditional line of sight

integration, for similar errors in the generated images.

\"Waves and Fluctuations in Non-Maxwellian Plasmas.\" Seminar by Herbert Gunell, Dept. of Physics and Astronomy, University of Iowa.

A simple pole expansion can be used to model the distribution function for

the purpose of calculating dispersion relations for electron waves

(Lfgren and Gunell, Phys. Plasmas, vol. 4, pp.3469-3476, 1997) and

ion-acoustic-like waves (Gunell and Skiff, Phys. Plasmas vol. 8, pp. 3550-3557, 2001). The

expansion is a rational function of the complex phase velocity, and the

integration along the real axis is reduced to a sum of the residues at the

poles of the expansion of the distribution function.

For waves on the ion acoustic time scale we find that slow weakly damped

modes exist in two-temperature plasmas, and in plasmas with beam-like

tails, i.e. plasmas where the ion distribution consists of two components

centred at different velocity. These slow, weakly damped, acoustic-like

modes exist also when the tail component constitutes a small fraction of

the total ion density. These weakly damped modes have been observed in

laboratory experiments (Skiff, De Souza-Machado, Noonan, Case, and Good,

Phys. Rev. Letters, vol. 81, p. 5829, 1998). For plasmas with equal ion

and electron temperatures weakly damped modes are found when there is a

depletion of the high energy tails. Weakly damped modes are also found in

plasmas with equal ion and electron temperatures in the presence of a low

density cold ion component.

Electrostatic fluctuations appear in stable plasmas due to the

discreteness of the plasma particles. The calculation of the spectral

density of these fluctuations in an isotropic three-dimensional plasma

through superposition of the electric fields of dressed test particles is

described in textbooks (e. g. Krall and Trivelpiece, Principles of Plasma

Physics. New York: McGraw-Hill, 1973). The test particle method has been

used to calculate the spectral density for electrostatic fluctuations in a

plasma where the particles follow a kappa distribution (Mace, Hellberg,

and Treumann, J. Plasma Physics, vol. 59, pp.393-416, 1998).

Here we show how the electrostatic fluctuations can be calculated for in

plasmas where both the ion and electron distributions are described by

simple pole expansions, in 1D and isotropic 3D plasmas. We present

calculations of the spectral density of the fluctuations as a function of

frequency and wavenumber. For comparison with measurements we integrate

over wave number to obtain the spectral density as a function of

frequency only.

11 January 2001

\"Modelling small-scale mountain lee-waves over Kiruna\", by Sheila Kirkwood, IRF, Kiruna [Abstract]

16 January 2001

\"The Munin Project\", by Olle Norberg, IRF, Kiruna

13 February 2001

\"Simulations of Charge-Exchange Processes near Mars\", by Mats Holmström, IRF, Kiruna [Abstract]

15 February 2001

\"The Physics of the Cusp from an Interball Perspective\", by Ingrid Sandahl, IRF, Kiruna [Abstract]

22 February 2001

\"Numerical simulations of the One-Dimensional Vlasov Equation\" by Bengt Eliasson, Departments of Scientific Computing and Astronomy and Space Physics, Uppsala [Abstract]

Friday, 23 February 2001 (10.30-11.30)

\"The Solar Wind and Geomagnetic Storms\" by Prof. Y. Kamide, STE LAB, University of Nagoya, Japan

1 March 2001

\"Interplanetary Dust Studies using Large Aperture Radars meteor observations\" by Diego Janches, IRF, Kiruna

6 March 2001

Professor A. Suzuki, Saga University, Japan. A seminar presenting his university, its education/research system and his work on Magsat satellite data.

15 March 2001

\"Energized heavy ions measured by Interball -2 satellite\" by Sachiko Joko, IRF, Kiruna [Abstract]

16 March 2001

\"Lower Hybrid Cavities and Other Plasma Phenomena in the Subauroral Region\" by Solveig Høymork, IRF, Kiruna [Abstract]

22 March 2001, 10:00 (10 am)

\"Fine Structures in Auroral Emissions\" by Jim LaBelle, Dartmouth College [Abstract]

22 March 2000, 13:30 (1.30 pm)

\"Wave Propagation in Inhomogeneous Plasmas\" by Hans Pécseli, University of Oslo, Norway [Abstract]

5 April 2001

Reports from EGS XXVI General Assembly in Nice, France, 25-30 March 2001

10 April 2001

\"Direct Magnetosheath Plasma Injections into the Closed Geomagnetic Field Region Observed at Mid- and Low-altitudes\" by Yamauchi Masatoshi, IRF, Kiruna [Abstract]

26 April 2001

\"Motion and Origin of the Noon Poleward Moving Auroral Arcs\" by Alexander Kozlovsky, Oulu University, Finland [Abstract]

8 May 2001

\"Imaging of PSCs in 0-3 dimensions\" by Carl-Fredrik Enell, IRF, Kiruna [Abstract]

10 May 2001

\"Inertial Resistivity and Current Limitation in a Collision-free and Inhomogeneous Plasma\" by Martin Bohm, Department of Space Physics, Umeå University, Kiruna [Abstract]

15 May 2001

\"The Frontal Systems, Fundamentals\", by Narayana Rao, IRF, Kiruna

ABSTRACTS

\"Numerical simulations of the One-Dimensional Vlasov Equation\", by Bengt Eliasson, Department of Scientific Computing and Department of Astronomy and Space Physics, Uppsala

In order to facilitate numerical simulations of plasma

phenomena where kinetic processes are important, we have

studied the technique of Fourier transforming the Vlasov equation

analytically in the velocity space, and solving the resulting

equation numerically. Special attention has been paid to the

boundary conditions of the Fourier transformed system, avoiding

the so-called recurrence phenomenon.

I will make a short presentation of the numerical techniques

and then present some numerical results; the process of

electrons getting trapped in waves (nonlinear Landau damping),

comparison with thery of linear waves etc.

We are currently looking on a problem of tunneling of information

throught the ionosphere, where the tunneling may be caused by

electrons trapped in the self-consistent electrostatic potential

due to the ion density profile. I will show some

numerical results from this problem.

\"The physics of the cusp from an Interball perspective\", by Ingrid Sandahl, IRF

The Interball project has given important contributions to our

understanding of the morphology and the physical processes in the cusp and

cleft. Interball-Tail and Magion-4 have performed more extensive

measurements in the high altitude cusp than any previous spacecraft.

Interball has also been a part in the ISTP program and data have been used

in many multipoint studies. In this paper cusp studies based entirely or

partly on Interball data will be reviewed.

The high altitude cusp/cleft is always a clearly distinguishable feature.

It is wider than suggested by direct mapping from low altitude, but the

position is controlled by the solar wind in a similar way as the low

altitude cusp. The dependence of the high altitude cusp position on IMF By

is, however, smaller than expected. Above the cusp/cleft there is almost

always a region of strong ULF turbulence and low magnetic field, the

turbulent boundary layer, TBL. The TBL extends tailward from the cusps and

is proposed to be related to the magnetospheric \"sash\".

The cusp is the site of very many physical processes. It acts like a funnel

collecting magnetosheath plasma into the magnetosphere. A number of

different plasma entry mechanisms are supported by the data including

direct plasma entry through the turbulent boundary layer, direct entry

along open high-latitude field lines, sub-solar point reconnection, and

lobe reconnection. For the overall magnetosheath plasma entry into the

magnetosphere, however, the magnetotail boundary is probably more important than the cusp.

Cusp energetic particles (Å 100 keV-MeV) are observed by Interball, but

their origin is not well understood. One view is that they have drifted to

the cusp from the ring current and outer radiation belt.

Acceleration and outflow of ionospheric plasma also take place in the cusp.

\"Simulations of Charge-Exchange Processes near Mars\", by Mats Holmström, IRF-Kiruna

Ions interact with neutrals by charge-exchange.

We study the interaction between the solar wind

and Mars\' exosphere.

The results of, and methods used in, the

simulations of two different problems are presented.

The production of energetic neutral atoms (ENAs)

and the production of X-rays, near Mars.

The production rate computations are based on an

empirical proton flow model and an exospheric model.

Using these parametric models, X-ray and ENA images

are generated by line-of-sight integration

(the forward problem).

The possibility of detecting the X-ray emissions

from Mars and Venus using the X-ray observatories

Chandra and XMM-Newton is discussed.

To speed up the computations and control the error,

a new algorithm for evaluation of line-of-sight

integrals is presented.

We also discuss the inverse problem of

extracting flow parameters from measured

ENA and X-ray images.

\"Modelling small-scale mountain lee-waves over Kiruna\", by Sheila Kirkwood, IRF.

Nacreous clouds, the brightly coloured type of polar straospheric clouds

which are often seen in the Kiruna area in January, often show clear

wave structure. The wavelength of the wave structures are of the order 30 km

or less. Model simulations of mountain lee waves in the stratosphere using

the MM5 meteorological model have been made for recent ozone research

campaigns by German and British groups. However, the lee-waves in these

simulations have have wavelengths of 100 km or more. There is clearly a

need to model the smaller-scale waves to aid in interpretation of

photographic records of the clouds, and ESRAD radar observations of the

vertical winds associated with lee-waves.

In this seminar a relatively simple model for small scale waves will be

presented. The model uses a 1-km resolution digital terrain model over

northern Scandinavia, synoptic atmospheric wind and buoyancy data from

UKMO assimilations and wave refrective index and ray-tracing concepts as

described by Salby.

The audience are invited to discuss how this model could be used in our

research and how it might usefully be improved.

\"Energized heavy ions measured by Interball-2 satellite\", by Sachiko Joko, IRF.

*Joko, S., IRF-K, Sweden, sachiko.joko@irf.se
Sandahl, I., IRF-K, Sweden, ingrid.sandahl@irf.se
Yamauchi, M., IRF-K, Sweden, masatoshi.yamauchi@irf.se
Sergienko, T., IRF-K, Sweden, timothy.sergienko@irf.se

Upward moving heavy ions with energies of up to at least 600 eV are

studied using the PROMICS-3 instrument on board the Interball-2

(Aurora Probe) satellite. While many past studies revealed O+ outflow

from the ionosphere, non-thermal escaping heavy ions, like N2+, NO+

and O2+, have not been well investigated, partly because of a lack of

proper instrumentation in previous mid- and high-altitude satellites.

PROMICS-3 on board Interball-2 is capable of measuring non-thermal

heavy ions because the instrument shares a mass spectrometer mode

(1-64 amu/q for 100 eV and 600 eV positive ions) and an energy

spectrometer mode (4 eV-70 keV ions for four masses and 0.3-35 keV

electrons).

We have examined all the Interball-2 observations (October 1996 -

December 1999) of heavy ions (m/q > 16) during geomagnetically

active periods (Kp >= 4). Heavy ions are observed in all MLT, i.e., in the noon

(cusp), dawn, dusk and midnight. According to the comparison between mass spectra

of upward moving heavy ions and the energy spectra of H+, O+,He+ and

He++ in the transverse direction, heavy ions events seem to be

associated with energized and upflowing O+ events.

These appear to be caused by large potential drops, seen as the ion

beam energy and related to plasma injection from the solar wind or the

plasma sheet.

Note:

1. \"Energized Heavy Ions\" should be changed like this;

\"Molecular Ions\". Compared to other studies on

this subject, 600eV that I\'m now focusing on as a

fixed energy is much higher than others, but I prefer

just saying \"molecular ions\" or \"heavy ions\" (this

means \'heavier than lighter ions like O+ and N+\').

2. I\'d like to clarify the physical mechanism of \"molecular

ions upflowing (escaping from the Earth)\" as the goal

of this study, but I\'m still under stastical study, which

means that I also encourage audiences to give me any ideas on this.

\"Lower Hybrid Cavities and Other Plasma Phenomena in the Subauroral Region\", by Solveig Høymork, IRF.

Solveig Høymork will present the main points in her thesis which analyses data from two Swedish satellites, Freja and Astrid-2. These satellites orbited the earth over the poles and took measurements in the auroral zone at heights of 1700 km and 1000 km respectively. This is the upper ionosphere where a large proportion of the atoms are ionized, creating a plasma. The study is restricted to the subauroral region. This area is expected to be less dynamic than the area in which aurora is usually visible. Nevertheless exciting phenomena occur there as well. Data shows localized thinning in plasma density, known as cavities. Both small-scale (ca 50 m) and large-scale (ca 1000 km) cavities have been observed. There are many physical processes that can lower the local density of plasma and thus create cavities, for example wave-particle interaction, electric fields and plasma transport. The thesis deals with several different types of cavities and localized higher density ion clouds, and gives possible explanations as to why these occur.

Both Freja and Astrid-2 were relatively cheap satellites. They have supplied a wealth of very interesting data and contributed to an increased understanding of our universe and some of the processes which affect its environment. It is becoming increasingly important to understand the environment in space , as more and more human activity takes place there (for example commercial satellites and space travel).

\"Fine Structures in Auroral Emissions\", by Jim LaBelle, Dartmouth College.

The aurora emits a variety of types of radio waves,

and most of these exhibit frequency fine structure;

i.e., they are composed of multiple discrete features

which often vary in frequency. This talk addresses the

fine structure in two of these emissions: auroral roar

and auroral Lanmuir waves. After reviewing the experimental

evidence for the fine structure of these emissions,

revealed in both ground-based and rocket-borne wave

receiver data, we explore the possibility that these

fine structures are consequences of the inhomogeneity

inherent in the auroral plasma. We put forth that both types

of fine structure may be explained by considering wave

excitation in the presence of density structures that

impose an eigenmode structure on the waves.

\"Wave Propagation in Inhomogeneous Plasmas\", by Hans Pécseli, University of Oslo, Norway

Models for describing the properties of waves propagating in inhomogeneous

plasmas are reviewed. Particular attention is given to electron plasma

waves (Langmuir waves) in plasmas containing density gradients, Alfvén

waves in inhomogeneous plasmas and ion sound waves in magnetized plasmas with inhomogeneous electron temperatures. It is shown how it can be argued that these waves are not following any dispersion relation for inhomogeneous conditions, and the concept is then \"de-mystified\".

\"Direct Magnetosheath Plasma Injections into the Closed Geomagnetic Field Region Observed at Mid- and Low-altitudes\", by M. Yamauchi

Some decade ago observations of Viking showed that direct solar wind

injection may occur deep inside the CPS region. Since then other

observations of plasma injection into CPS have been reported, from highly

transient injections to more stagnant ones with different magnetic

(field-aligned current) signatures. Such observations raises a question

identifying/defining the open-closed boundary.

Satellite cusp observations in 1990\'s also indicate that we do not have a

simple open-or-closed concept. It seems necessary to introduce a fuzzy

concept for the openness of regions such as \"semi-open\" and \"extra-open\"

(extra here means accessibility of ionospheric ions to the magnetosheath).

We also report on recent searches for direct plasma transfer with other

satellites. Interball-tail, from similar altitudes, found similar types of

events. Freja, from low-altitude, sometimes observes cusp-like injections

into early dawn and late dusk. Finally, data from Astrid-2 display

characteristics of ion clouds which could be attributed to direct

injections of the solar wind.

\"Motion and Origin of the Noon Poleward Moving Auroral Arcs\", by Alexander Kozlovsky, Oulu University, Finland

Near-noon auroral arcs were investigated together with the

ionospheric plasma flows derived from the EISCAT VHF measurements over

Svalbard. The auroral arc motion was monitored at 0800 - 1300 MLT by the

all-sky camera during four days in December 1998. It has been found that the

noon auroral arcs move poleward at the velocity of the order of 200 - 600

m/s, and this velocity does not show any dependence on the velocity of the

ionospheric plasma convection along the same direction. The arcs appear at 5

- 15 min after strong changes (up to 4 km/s) in the meridional plasma flow,

which resulted from variations in the interplanetary magnetic field.

Particle precipitation data from DMSP satellites show location of the

auroras on closed magnetic field lines in a vicinity of the boundary between

BPS and LLBL. Spectrums of the northward electric field variations measured

by the radar demonstrate clear peaks corresponding to the FLR oscillations.

Period of the oscillations increases from 6 min at 74.3 MLAT to 14 min at

76.4 MLAT. Corresponding spectral characteristics were observed in the

magnetic field measured on ground. The observed features allow to suggest

that the noon auroral arcs arise as a result of interference between Alfvén

field line eigenmode toroidal oscillations on different L-shells. The FLR

oscillations at the near-cusp L-shells are excited by the Alfvén impulse

associated with the convection disturbance followed after variations in

interplanetary parameters.

\"Imaging of PSCs in 0-3 dimensions\" by Carl-Fredrik Enell

The method generally used in studies of polar stratospheric clouds is

optical remote sensing from the ground, balloons or satellites. This

can be thought of as imaging in 0-3 dimensions depending on the technique

used and the corresponding geometry.

This seminar is indended as a discussion of the data we have available:

-Colour index

-Lidar

-Images

and the best ways to use and interpret these data, including some

mathematical problems encountered in the analysis.

Everybody is welcome to bring ther own pictures, lists of PSC observations,

and so on.

\"Inertial Resistivity and Current Limitation in a Collision-free and Inhomogeneous Plasma\" by Martin Bohm, Department of Space Physics, Umeå University, Kiruna

Measurements in space show that a collision-free plasma can support large potential drops. In interplanetary space collective processes, connected with plasma turbulence, can assume the roll of collisions. Inhomogeneous and collision-free plasmas may support large potential drops on the electron time scale even for free-streaming electrons in time-independent motion. This \"inertial resistivity\" has recently been used to interpret measured magnetic-field-aligned potential drops in the auroral zone of the Earth. In the seminar the results of one-dimensional particle-in-cell simulations of the response of an inhomogeneous plasma to a suddenly applied high voltage drop Va are presented. The results are compared with a theoretical model of the inertial conductance and with experiments. In the initial phase inertial conductivity dominates. Then the simulations show a sharp current drop associated with turbulence and reflection of current carrying electrons. In this case turbulent resistivity is the likely current limiting mechanism.

14 December 1999

\"Ring current proton precipitation and its consequence to the ionosphere\" by Yusuke Ebihara [Abstract]

25 November 1999

\" Source and loss processes of magnetospheric plasma\" by Bengt Hultqvist

23 November 1999

\"Artificial airglow and analysis of ALIS data\" by Björn Gustavsson [Abstract]

16 November 1999

Seminarium: Origin of Life, Hans Nilsson och Ingrid Sandahl [Abstract]

11 November 1999

\"Meteorskur värdig millennieskiftet?\" by Asta-Pellinen-Wannberg [Abstract]

9 November 1999

\"ENA Imaging of Planetary Magnetospheres\" by Pontus C:son Brandt [Abstract]