[1] C.-F. Enell, B. Gustavsson, B. U. E. Brändström, T. I. Sergienko, P. T. Verronen, P. Rydesäter, and I. Sandahl. Tomography-like retrieval of auroral volume emission ratios for the 31 january 2008 hotel payload 2 event. Geosci. Instrum. Method. Data Syst. Discuss., 2:1-21, 2012. [ bib | .pdf ]
[2] H. Dahlgren, B. Gustavsson, B. S. Lanchester, N. Ivchenko, U. Brändström, D. K. Whiter, T. Sergienko, I. Sandahl, and G. Marklund. Energy and flux variations across thin auroral arcs. Ann. Geophys., 29:1699-1712, October 2011. [ bib | DOI ]
[3] K. Axelsson, T. Sergienko, I. Sandahl, and U. Brändström. A study on the possibility to deduce the 2D distribution of the auroral electron precipitation from multi wavelength optical measurements with auroral imagers. In Sección Especial: 37th AMASON Óptica Pura y Aplicada, volume 44, pages 605-609. Sociedad Española de Óptica, 2011. [ bib ]
[4] B. U. E. Brändström, C.-F. Enell, O. Widell, , T. Hansson, D. Whiter, S. Mäkinen, D. Mikhaylova, K. Axelsson, F. Sigernes, N. Gulbrandsen, N. M. Schlatter, A. G. Gjendem, L. Cai, J. P. Reistad, M. Daae, T. D. Demissie, Y. L. Andalsvik, O. Roberts, S. Poluyanov, and S. Chernouss. Results from the intercalibration of optical low-light calibration sources 2011. Geosci. Instrum. Method. Data Syst. Discuss., pages 91-107, 2011. Paper in open discussion phase. [ bib | .pdf ]
[5] Carl-Fredrik Enell, Jonas Hedin, Jacek Stegman, Georg Witt, Martin Friedrich, Werner Singer, Gerd Baumgarten, Bernd Kaifler, Ulf-Peter Hoppe, Björn Gustavsson, Urban Brändström, Mikhail Khaplanov, Antti Kero, Thomas Ulich, and Esa Turunen. The Hotel Payload 2 campaign: Overview of NO, O and electron density measurements in the upper mesosphere and lower thermosphere. J. Atmos. Solar and Terr. Phys., 73:2228-2236, 2011. [ bib | DOI | http ]
[6] I. Sandahl, U. Brändström, and T. Sergienko. Fine structure of aurora. Int. J. Remote Sensing, 32(11):2947-2972, 2011. [ bib ]
[7] I. Sandahl, U. Brändstöm, and T. Sergienko. Networks of people and infrastructure for ground-based auroral research. In Sección Especial: 37th AMASON Óptica Pura y Aplicada), volume 44 of Opt. Pura Apl., pages 581-591. Sociedad Española de Óptica, 2011. [ bib ]
[8] YM Tanaka, T. Aso, B. Gustavsson, K. Tanabe, Y. Ogawa, A. Kadokura, H. Miyaoka, T. Sergienko, U. Brändström, and I. Sandahl. Feasibility study on generalized-aurora computed tomography. Ann. Geophys, 29:551-562, 2011. [ bib ]
[9] VV Safargaleev, TI Sergienko, AE Kozlovsky, I. Sandahl, U. Brändström, and DN Shibaeva. Electric field enhancement in an auroral arc according to the simultaneous radar (eiscat) and optical (alis) observations. Geomagnetism and Aeronomy, 49(3):353-367, 2009. [ bib ]
[10] T. Sergienko, I. Sandahl, B. Gustavsson, U. Brändström, L. Andersson, and Å. Steen. A study of fine structure of diffuse aurora with ALIS-FAST measurements. Ann. Geophys., 26:3185-3195, October 2008. [ bib ]
We present results of an investigation of the fine structure of the night sector diffuse auroral zone, observed simultaneously with optical instruments (ALIS) from the ground and the FAST electron spectrometer from space 16 February 1997. Both the optical and particle data show that the diffuse auroral zone consisted of two regions. The equatorward part of the diffuse aurora was occupied by a pattern of regular, parallel auroral stripes. The auroral stripes were significantly brighter than the background luminosity, had widths of approximately 5 km and moved southward with a velocity of about 100 m/s. The second region, located between the region with auroral stripes and the discrete auroral arcs to the north, was filled with weak and almost homogeneous luminosity, against which short-lived auroral rays and small patches appeared chaotically. From analysis of the electron differential fluxes corresponding to the different regions of the diffuse aurora and based on existing theories of the scattering process we conclude the following: Strong pitch angle diffusion by electron cyclotron harmonic waves (ECH) of plasma sheet electrons in the energy range from a few hundred eV to 3 4 keV was responsible for the electron precipitation, that produced the background luminosity within the whole diffuse zone. The fine structure, represented by the auroral stripes, was created by precipitation of electrons above 3 4 keV as a result of pitch angle diffusion into the loss cone by whistler mode waves. A so called

[11] B. Gustavsson, M. J. Kosch, A. Senior, A. J. Kavanagh, B. U. E. Brändström, and E. M. Blixt. Combined EISCAT radar and optical multispectral and tomographic observations of black aurora. J. Geophys. Res., 113(A12):A06308, June 2008. [ bib | DOI | http ]
Black auroras are recognized as spatially well-defined regions within a uniform diffuse auroral background where the optical emission is significantly reduced. Black auroras typically appear post-magnetic midnight and during the substorm recovery phase, but not exclusively so. We report on the first combined multimonochromatic optical imaging, bistatic white-light TV recordings and incoherent scatter radar observations of black aurora by EISCAT of the phenomenon. From the relatively larger reduction in luminosity at 4278 Å than at 8446 Å we show that nonsheared black auroras are most probably not caused by downward directed electrical fields at low altitude. From the observations, we determine this by relating the height and intensity of the black aurora to precipitating particle energy within the surrounding background diffuse aurora. The observations are more consistent with an energy selective loss cone. Hence the mechanism causing black aurora is most probably active in the magnetosphere rather than close to Earth.

Keywords: Atmospheric Composition and Structure: Airglow and aurora, Magnetospheric Physics: Energetic particles: precipitating, Magnetospheric Physics: Electric fields (2411), Ionosphere: Ionosphere/magnetosphere interactions (2736)
[12] T. Aso, B. Gustavsson, K. Tanabe, U. Brändström, T. Sergienko, and I. Sandahl. A proposed Bayesian model on the generalized tomographic inversion of aurora using multi-instrument data. In Proceedings of the 33rd Annual European Meeting on Atmospheric Studies by Optical Methods, volume 292, pages 105-111. Swedish Institute of Space Physics, 2008. [ bib ]
[13] I. V. Golovchanskaya, B. V. Kozelov, T. I. Sergienkoand U. Brändström, H. Nilsson, and I. Sandahl. Scaling behavior of auroral luminosity fluctuations observed by ALIS. J. Geophys. Res., 113(A10303), 2008. [ bib | DOI ]
[14] I. Sandahl, T. Sergienko, and U. Brändström. Fine structure of optical aurora. J. Atmos. Solar and Terr. Phys., 70:2275-2292, 2008. [ bib | DOI ]
[15] Björn Gustavsson, T. B. Leyser, M. Kosch, M. T. Rietveld, Åke Steen, Berndt Urban Eugén Brändström, and Takehiko Aso. Electron gyroharmonic effects in ionization and electron acceleration during high-frequency pumping in the ionosphere. Phys. Rev. Lett., 97(195002), 2006. [ bib ]
[16] B. Gustavsson, T. Sergienko, M. J. Kosch, M. T. Rietveld, B. U. E. Brändström, T. B. Leyser, B. Isham, P. Gallop, T. Aso, M. Ejiri, Å. Steen, T. Grydeland, C. la Hoz, K. Kaila, J. Jussila, and H. Holma. The electron distribution during HF pumping, a picture painted with all colors. Ann. Geophys., 23(5):1747-1754, 2005. [ bib | http | .pdf ]
The shape of the electron energy distribution has long been a central question in the field of high-frequency radio-induced optical emission experiments. This report presents estimates of the electron energy distribution function, fe(E), from 0 to 60 eV based on optical multi-wavelength (6300, 5577, 8446, 4278 Å) data and 930-MHz incoherent scatter radar measurements of ion temperature, electron temperature and electron concentration. According to our estimate, the electron energy distribution has a depression at around 2 eV, probably caused by electron excitation of vibrational states in N2, and a high energy tail that is clearly supra-thermal. The temporal evolution of the emissions indicates that the electron temperature still plays an important role in providing electrons with energies close to 2 eV. At the higher energies the electron energy distribution has a non-thermal tail.

Keywords: electron distribution, artificial airglow, active experiments
[17] Asta Pellinen-Wannberg, Edmond Murad, Björn Gustavsson, Urban Brändström, Carl-Fredrik Enell, Christopher Roth, Iwan P. Williams, and Åke Steen. Optical observations of water in Leonid meteor trails. Geophys. Res. Lett., 31, February 2004. [ bib | DOI | .pdf ]
[18] Urban Brändström. The Auroral Large Imaging System - Design, operation and scientific results. PhD thesis, Swedish Institute of Space Physics, Kiruna, Sweden, October 2003. (IRF Scientific Report 279), ISBN: 91-7305-405-4. [ bib ]
[19] Urban Brändström, Torbjörn Lövgren, Arne Moström, Carl-Fredrik Enell, Björn Gustavsson, Takehiko Aso, Masaki Ejiri, Åke Steen, and Peter Rydesäter. Brief report on ALIS (Auroral Large Imaging System), a new all-sky camera in Kiruna and auroral imaging using a mini-DV camcorder. Sodankylä Geophysical publication series, 92:89-92, August 2003. [ bib ]
[20] Carl-Fredrik Enell, Urban Brändström, Björn Gustavsson, Sheila Kirkwood, Kerstin Stebel, and Åke Steen. Case studies of the development of polar stratospheric clouds using bistatic imaging. Ann. Geophys., 21:1869-1878, 2003. [ bib | http | .pdf ]
[21] Björn Gustavsson, Berndt Urban Eugén Brändström, Åke Steen, Timophey Sergienko, Thomas B. Leyser, M. T. Rietveld, Takehiko Aso, and Masaki Ejiri. Nearly simultaneous images of HF-pump enhanced airglow at 6300 Å and 5577 Å. Geophys. Res. Lett., 29(24):2220, 2002. paper No. 10.1029/2002GL015350. [ bib ]
[22] S. Kirkwood, V. Barabash, B. U. E. Brändström, A. Moström, K. Stebel, N. Mitchell, and W. Hocking. Noctilucent clouds, PMSE and 5-day planetary waves: a case study. Geophys. Res. Lett., 29(10):50-1-4, 2002. [ bib ]
[23] T. B. Leyser, B. U. E. Brändström, B. Gustavsson, T. Sergienko, and M. T. Rietveld. Enhanced airglow by high frequency electromagnetic pumping with the EISCAT heating facility and observed by the multi-station auroral large imaging system ALIS. In URSI. URSI, 2002. paper 815, 2002. [ bib ]
[24] B. Gustavsson, T. Sergienko, M. T. Rietveld, F. Honary, Å Steen, B. U. E. Brändström, T. B. Leyser, A. L. Aruliah, T. Aso, and M. Ejiri. First tomographic estimate of volume distribution of enhanced airglow emission caused by HF pumping. J. Geophys. Res., 106(A12):29105-29123, December 2001. [ bib ]
[25] Björn Gustavsson, Å. Steen, T. Sergienko, and B. U. E. Brändström. Estimate of auroral electron spectra, the power of ground-based multi-station optical measurements. Phys. Chem. Earth, 26(1-3):189-194, 2001. [ bib ]
[26] Vartan Tagirov, V. A. Arinin, Urban Brändström, A. Pajunpää, and V.V. Klimenko. Atmospheric optical phenomena caused by powerful rocket launches. J. Spacecraft and Rockets, 37(6):812-821, November 2000. [ bib ]
[27] M. Hedin, I. Häggström, Asta Pellinen-Wannberg, I. Häggström, Laila Andersson, Urban Brändström, Björn Gustavsson, Åke Steen, Assar Westman, Gudmund Wannberg, Tony van Eyken, Takehiko Aso, Cynthia Cattell, Charles W. Carlson, and Dave Klumpar. 3-D extent of the main ionospheric trough -a case study. Adv. Polar Upper Atmos. Res., 14:157-162, August 2000. [ bib ]
[28] David Rees, Mark Conde, Åke Steen, and Urban Brändström. The first daytime ground-based optical image of the aurora. Geophys. Res. Lett., 27(3):313-316, February 2000. [ bib ]
[29] Takehiko Aso, Åke Steen, Urban Brändström, Björn Gustavsson, Akira Urashima, and Masaki Ejiri. ALIS - a state of the art optical observation network for the exploration of polar atmospheric processes. Adv. Space Res., 26(6):917-924, 2000. [ bib ]
[30] Carl-Fredrik Enell, Björn Gustavsson, Åke Steen, Urban Brändström, and Peter Rydesäter. Multistatic imaging and optical modelling of nacreous clouds. Phys. Chem. Earth, 25(5-6):451-457, 2000. [ bib ]
[31] T. B. Leyser, B. Gustavsson, B. U. E. Brändström, F. Honary Å. Steen, Takehiko Aso M. T. Rietveld, and Masaki Ejiri. Simultaneous measurements of high-frequency pump-enhanced airglow and ionospheric temperatures at auroral latitudes. Adv. Polar Upper Atmos. Res., 14:1-11, 2000. [ bib ]
[32] T. Sergienko, B. Gustavsson, Å. Steen, U. Brändström, M. Rietveld, T. Leyser, and F. Honary. Analysis of excitation of the 630.0 nm airglow during heating experiment in Tromsø on February 16, 1999. Phys. Chem. Earth, 25:531-535, 2000. [ bib ]
[33] B. U. E. Brändström, T. B. Leyser, Å. Steen, M. T. Rietveld, B. Gustavsson, T. Aso, and M. Ejiri. Unambigous evidence of HF pump-enhanced airglow. Geophys. Res. Lett., 26(23):3561-3564, December 1999. [ bib ]
[34] Akira Urashima, Takehiko Aso, Masaki Ejiri, Åke Steen, U. Brändström, and B. Gustavsson. Camera calibration by integrating sphere for the auroral tomography observation. Adv. Polar Upper Atmos. Res., 13:79-88, September 1999. [ bib ]
[35] O. Amm, A. Pajunpää, and U. Brändström. Spatial distribution of conductances and currents associated with a North-South auroral form during a multiple substorm period. Ann. Geophys., 17:1385-1396, 1999. [ bib ]
[36] Takehiko Aso, Masaki Ejiri, Akira Urashima, Hiroshi Miayoka, Åke Steen, Urban Brändström, and Björn Gustavsson. First results from auroral tomography from ALIS-Japan multi-station observations in March 1995. Earth Planets Space, 50:81-86, 1998. [ bib ]
[37] Takehiko Aso, Masaki Ejiri, Akira Urashima, Hiroshi Miyaoka, Åke Steen, Urban Brändström, and Björn Gustavsson. Auroral tomography analysis of a folded arc observed at the ALIS-JAPAN multi-station campaign on March 26, 1995. In Proceedings of the NIPR Symposium on upper atmosphere Physics, volume 11, pages 1-10, Tokyo, January 1998. National Institute of Polar Research. [ bib ]
[38] Michael I. Pudovkin, Åke Steen, and Urban Brändström. Vorticity in the magnetospheric plasma and its signature in the aurora dynamics. Space Science Rev., 80:411-444, 1997. [ bib ]
[39] Anasuya L. Aruliah, A. D. Farmer, David Rees, and Urban Brändström. The seasonal behaviour of high-latitude thermospheric winds and ion velocities observed over one solar cycle. J. Geophys. Res., 101(A7):15701-15711, July 1996. [ bib ]
[40] David J. Knudsen, G. Haerendel, Stefan Buchert, M.C. Kelley, Å. Steen, and U. Brändström. Incoherent scatter radar spectrum distorsions from intense auroral turbulence. J. Geophys. Res., 98:9459-9471, 1993. [ bib ]

This file was generated by bibtex2html 1.91.