pes

• Sato, Hiroatsu; Pecseli, Hans Laszlo; Trulsen, Jan Karsten; Sandholt, Per Even & Farrugia, Charles J. (2022). Impulse-driven oscillations of the near-Earth's magnetosphere. Annales Geophysicae. ISSN 0992-7689. 40(6), s. 641–663. doi: 10.5194/angeo-40-641-2022. Fulltekst i vitenarkiv Vis sammendrag

  It is argued that a simple model based on magnetic image arguments suffices to give a convincing insight into both the basic static as well as some transient dynamic properties of the near-Earth's magnetosphere, particularly accounting for damped oscillations being excited in response to impulsive perturbations. The parameter variations of the frequency are given. Qualitative results can also be obtained for heating due to the compression of the radiation belts. The properties of this simple dynamic model for the solar wind–magnetosphere interaction are discussed and compared to observations. In spite of its simplicity, the model gives convincing results concerning the magnitudes of the near-Earth's magnetic and electric fields. The database contains ground-based results for magnetic field variation in response to shocks in the solar wind. Here, the observations also include data from the two Van Allen satellites.

• Sandholt, Per Even; Farrugia, C. J. & Denig, W. F. (2015). Transitions between states of magnetotail-ionosphere coupling and the role of solar wind dynamic pressure: The 25 July 2004 interplanetary CME case. Annales Geophysicae. ISSN 0992-7689. 33(4), s. 427–436. doi: 10.5194/angeo-33-427-2015. Fulltekst i vitenarkiv
• Muzamil, Fathima Muzleena; Farrugia, Charlie J.; Torbert, Roy B.; Pritchett, Philip R.; Mozer, Forrest S. & Scudder, Jack D. [Vis alle 10 forfattere av denne artikkelen] (2014). Structure of a reconnection layer poleward of the cusp: Extreme density asymmetry and a guide field. Journal of Geophysical Research (JGR): Biogeosciences. ISSN 2169-8953. 119(9), s. 7343–7362. doi: 10.1002/2014JA019879. Fulltekst i vitenarkiv
• Sandholt, Per Even & Farrugia, Charlie (2014). Aspects of magnetosphere - ionosphere coupling in sawtooth substorms: a case study. Annales Geophysicae. ISSN 0992-7689. 32(10), s. 1277–1291. doi: 10.5194/angeo-32-1277-2014. Fulltekst i vitenarkiv
• Sandholt, Per Even; Farrugia, Charles J. & Denig, William F. (2014). M-I coupling across the auroral oval at dusk and midnight: repetitive substorm activity driven by interplanetary coronal mass ejections(CMEs). Annales Geophysicae. ISSN 0992-7689. 32(4), s. 333–351. doi: 10.5194/angeo-32-333-2014. Fulltekst i vitenarkiv
• Farrugia, C. J.; Erkaev, N. V.; Jordanova, VK; Lugaz, N.; Sandholt, Per Even & Mühlbachler, S. [Vis alle 7 forfattere av denne artikkelen] (2013). Features of the interaction of interplanetary coronal mass ejections/magnetic clouds with the Earth's magnetosphere. Journal of Atmospheric and Solar-Terrestrial Physics. ISSN 1364-6826. 99, s. 14–26. doi: 10.1016/j.jastp.2012.11.014. Fulltekst i vitenarkiv
• Sandholt, Per Even & Farrugia, C.J. (2012). Plasma flows, Birkeland currents and auroral forms in relation to the Svalgaard-Mansurov effect. Annales Geophysicae. ISSN 0992-7689. 30(5), s. 817–830. doi: 10.5194/angeo-30-817-2012. Fulltekst i vitenarkiv
• Andalsvik, Yngvild Linnea; Sandholt, Per Even & Farrugia, Charlie (2012). Substorms and polar cap convection: the 10 January 2004 interplanetary CME case. Annales Geophysicae. ISSN 0992-7689. 30(1), s. 67–80. doi: 10.5194/angeo-30-67-2012. Fulltekst i vitenarkiv
• Sandholt, Per Even; Andalsvik, Yngvild Linnea & Farrugia, C. J. (2012). The pulsed nature of the nightside contribution to polar cap convection: repetitive substorm activity under steady interplanetary driving. Annales Geophysicae. ISSN 0992-7689. 30(10), s. 1539–1553. doi: 10.5194/angeo-30-1539-2012. Fulltekst i vitenarkiv
• Andalsvik, Yngvild Linnea; Sandholt, Per Even & Farrugia, Charlie (2011). Dayside and nightside contributions to cross-polar cap potential variations: the 20 March 2001 ICME case. Annales Geophysicae. ISSN 0992-7689. 29, s. 2189–2201. doi: 10.5194/angeo-29-2189-2011. Fulltekst i vitenarkiv
• Siscoe, George L.; Farrugia, Charlie J. & Sandholt, Per Even (2011). Comparison between the two basic modes of magnetospheric convection. Journal of Geophysical Research (JGR): Space Physics. ISSN 2169-9380. 116. doi: 10.1029/2010JA015842. Fulltekst i vitenarkiv
• Sandholt, Per Even; Andalsvik, Yngvild Linnea & Farrugia, Charlie (2010). Polar cap flow channel events: spontaneous and driven responses. Annales Geophysicae. ISSN 0992-7689. 28(11), s. 2015–2025. doi: 10.5194/angeo-28-2015-2010. Fulltekst i vitenarkiv
• Sandholt, Per Even; Andalsvik, Yngvild Linnea & Farrugia, Charlie (2010). Polar cap convection/precipitation states during Earth passage of two ICMEs at solar minimum. Annales Geophysicae. ISSN 0992-7689. 28(4), s. 1023–1042. Fulltekst i vitenarkiv
• Farrugia, Charlie; Erkaev, N. V.; Maynard, N. C.; Richardson, I. G.; Sandholt, Per Even & Langmayr, D [Vis alle 11 forfattere av denne artikkelen] (2009). Effects on the distant geomagnetic tail of a fivefold density drop in the inner sheath region of a magnetic cloud: A joint Wind-ACE study. Advances in Space Research. ISSN 0273-1177. 44(11), s. 1288–1294. doi: 10.1016/j.asr.2009.07.003. Fulltekst i vitenarkiv
• Sandholt, Per Even & Farrugia, Charlie (2009). Plasma flow channels at the dawn/dusk polar cap boundaries: momentum transfer on old open field lines and the roles of IMF B-y and conductivity gradients. Annales Geophysicae. ISSN 0992-7689. 27(4), s. 1527–1554. Fulltekst i vitenarkiv
• Farrugia, CJ; Gratton, FT; Lund, EJ; Sandholt, Per Even; Cowley, SWH & Torbert, RB [Vis alle 14 forfattere av denne artikkelen] (2008). Two-stage oscillatory response of the magnetopause to a tangential discontinuity/vortex sheet followed by northward IMF: Cluster observations. Journal of Geophysical Research (JGR). ISSN 0148-0227. 113. doi: 10.1029/2007JA012800. Fulltekst i vitenarkiv
• Sandholt, Per Even & Farrugia, Charlie (2008). The role of external triggers in flow shear arcs in the dayside aurora. Annales Geophysicae. ISSN 0992-7689. 26, s. 2159–2177. Fulltekst i vitenarkiv
• Sandholt, Per Even & Farrugia, Charlie (2008). Polar observations of ion/electron bursts at the pre-dawn polar cap boundary: Evidence for internal reconnection of overdraped lobe flux. Annales Geophysicae. ISSN 0992-7689. 26, s. 2191–2202. Fulltekst i vitenarkiv
• Vorobjev, V.G.; Kornilov, I.A.; Kornilova, T.A.; Yagodkina, O.I.; Sandholt, Per Even & Lybekk, Bjørn (2008). Nighttime subvisual high-latitude auroras. Geomagnetism and Aeronomy. ISSN 0016-7932. 48(5), s. 606–614. doi: 10.1134/S0016793208050058. Fulltekst i vitenarkiv
• Lund, Eric; Farrugia, Charlie & Sandholt, Per Even (2008). Momentum transfer at the high-latitude magnetopause and boundary layers. Annales Geophysicae. ISSN 0992-7689. 26, s. 2449–2458. Fulltekst i vitenarkiv
• Sandholt, Per Even & Farrugia, Charlie (2007). Poleward moving auroral forms (PMAFs) revisited: responses of aurorae, plasma convection and Birkeland currents in the pre- and postnoon sectors under positive and negative IMF B-y conditions. Annales Geophysicae. ISSN 0992-7689. 25, s. 1629–1652. Fulltekst i vitenarkiv
• Sandholt, Per Even & Farrugia, C. J. (2007). Role of poleward moving auroral forms in the dawn-dusk auroral precipitation asymmetries induced by IMF B-y. Journal of Geophysical Research (JGR). ISSN 0148-0227. 112(A04203). doi: 10.1029/2006JA011952. Fulltekst i vitenarkiv
• Farrugia, CJ; Grocott, A; Sandholt, Per Even; Cowley, SWH; Miyoshi, Y & Rich, FJ [Vis alle 9 forfattere av denne artikkelen] (2007). The magnetosphere under weak solar wind forcing. Annales Geophysicae. ISSN 0992-7689. 25. Fulltekst i vitenarkiv
• Sandholt, Per Even & Farrugia, Charlie (2006). Spatiotemporal structure of the reconnecting magnetosphere under By-dominated interplanetary magnetic cloud conditions. Journal of Geophysical Research (JGR). ISSN 0148-0227. 111. doi: 10.1029/2005JA011514. Fulltekst i vitenarkiv
• Lund, EJ; Farrugia, CJ; Sandholt, Per Even; Kistler, LM; Fairfield, DH & Gratton, FT [Vis alle 12 forfattere av denne artikkelen] (2006). The changing topology of the duskside magnetopause boundary layer in relation to IMF orientation. Advances in Space Research. ISSN 0273-1177. 37, s. 497–500. Fulltekst i vitenarkiv
• Sandholt, Per Even; Farrugia, C. J.; Lund, E. J. & Denig, W. F. (2006). IMF By and the Spatio-Temporal Structure of the Dayside Aurora. I Tsurutani, B. (Red.), Recurrent Magnetic Storms: Corotating Solar Wind Streams. American Geophysical Union (AGU). ISSN 9780875904320. s. 213–233. Fulltekst i vitenarkiv
• Sandholt, Per Even; Dyrland, Margit & Farrugia, Charlie (2006). Dayside aurorae and polar arcs under south-east IMF orientation. Annales Geophysicae. ISSN 0992-7689. 24, s. 3421–3432. Fulltekst i vitenarkiv
• Sandholt, Per Even; Farrugia, Charles J. & Denig, W. F. (2004). Detailed dayside auroral morphology as a function of local time for southeast IMF orientation: implications for solar wind- magnetosphere coupling. Annales Geophysicae. ISSN 0992-7689. 22, s. 3537–3560. Fulltekst i vitenarkiv
• Farrugia, C. J.; Lund, E. J.; Sandholt, Per Even; Wild, JA; Cowley, SWH & Balogh, A [Vis alle 16 forfattere av denne artikkelen] (2004). Pulsed flows at the high-altitude cusp poleward boundary, and associated ionospheric convection and particle signatures, during a Cluster-FAST-SuperDARN-Sondrestrom conjunction under a southwest IMF. Annales Geophysicae. ISSN 0992-7689. 22, s. 2891–2905. doi: 10.1029/2003JA010121. Fulltekst i vitenarkiv
• Khan, Hina; Lester, M.; Davies, J. A.; Milan, Steve & Sandholt, Per Even (2004). Multi-instrument study of the dynamic cusp during dominant IMF B-y conditions. Annales Geophysicae. ISSN 0992-7689. 21, s. 693–708. Fulltekst i vitenarkiv
• Farrugia, C.J.; Sandholt, Per Even; Torbert, R. B. & Østgaard, Nikolai (2004). Temporal and spatial aspects of the cusp inferred from local and global ground- and space-based observations in a case study. Journal of Geophysical Research (JGR). ISSN 0148-0227. 109, s. art. no.–A04209. doi: 10.1029/2003JA010121. Fulltekst i vitenarkiv
• Sandholt, Per Even; Farrugia, C. J. & Denig, W. F. (2004). Dayside aurora and the role of IMF vertical bar B-y vertical bar/vertical bar B-z vertical bar: Detailed morphology and response to magnetopause reconnection. Annales Geophysicae. ISSN 0992-7689. 22, s. 613–628. Fulltekst i vitenarkiv
• Farrugia, Charles J.; Lund, E. J. & Sandholt, Per Even (2004). Pulsed flows at the high-altitude cusp poleward boundary, and associated ionospheric convection and particle signatures, during a CLUSTER - FAST - SuperDARN - Sondrestrom conjunction under a southwest IMF. Annales Geophysicae. ISSN 0992-7689. 22, s. 2891–2905. Fulltekst i vitenarkiv
• Sandholt, Per Even; Farrugia, Charles J. & Denig, W. F. (2004). Dayside aurora and the role of IMF |By/Bz|: detailed morphology and response to magnetopause reconnection. Annales Geophysicae. ISSN 0992-7689. 22, s. 613–613. Fulltekst i vitenarkiv
• Sandholt, Per Even; Moen, Jøran Idar; Farrugia, CJ; Cowley, SWH; Lester, M & Milan, SE [Vis alle 9 forfattere av denne artikkelen] (2003). Multi-site observations of the association between aurora and plasma convection in the cusp/polar cap during a southeastward (B-y similar or equal to vertical bar B-z vertical bar) IMF orientation. Annales Geophysicae. ISSN 0992-7689. 21, s. 539–558. Fulltekst i vitenarkiv
• Sandholt, Per Even (2003). Spontaneous and driven cusp dynamics: Optical aurora, particle precipitation, and plasma convection. Planetary and Space Science. ISSN 0032-0633. 51, s. 797–812. Fulltekst i vitenarkiv
• Sandholt, Per Even; Moen, Jøran Idar & Farrugia, Charles J. (2003). Multi-site ground-based observations of the association between aurora and plasma convection in the cusp/polar cap during south-eastward (BY~|BZ|)IMF orientation. Annales Geophysicae. ISSN 0992-7689. 21, s. 539–539. Fulltekst i vitenarkiv
• Farrugia, Charles J. & Sandholt, Per Even (2003). Temporal variations in a four-sheet field-aligned current system and associated aurorae as observed during a Polar-ground magnetic conjunction in the midmorning sector. Journal of Geophysical Research (JGR). ISSN 0148-0227. 109(A6). Fulltekst i vitenarkiv
• Sandholt, Per Even; Moen, Jøran Idar; Farrugia, Charles J.; Cowley, Stanley W. H.; Lester, Mark & Milan, Steve [Vis alle 9 forfattere av denne artikkelen] (2003). Multi-site observations of the association between aurora and plasma convection in the cusp/polar cap during a south-eastward IMF orientation. Annales Geophysicae. ISSN 0992-7689. 21, s. 539–539. Fulltekst i vitenarkiv
• Farrugia, Charles J.; Sandholt, Per Even; Maynard, Nelson; Torbert, Roy & Ober, Dan (2003). Temporal variations in a four-sheet field-aligned current system and associated aurorae as observed during a Polar-ground magnetic conjunction in the midmorning sector. Journal of Geophysical Research (JGR). ISSN 0148-0227. 108(6). Fulltekst i vitenarkiv
• Cowley, Stanley W. H.; Davies, J. A.; Grocott, A.; Khan, H.; Lester, Mark & McWilliams, K. A. [Vis alle 11 forfattere av denne artikkelen] (2003). Solar-wind-magnetosphere-ionosphere interactions in the Earth's plasma environment. Philosophical Transactions of the Royal Society of London. Biological Sciences. ISSN 0962-8436. 361, s. 113–126. Fulltekst i vitenarkiv
• Sandholt, Per Even & Farrugia, Charles J. (2003). Does the aurora provide evidence for the occurrence of antiparallel magnetopause reconnection? Journal of Geophysical Research (JGR). ISSN 0148-0227. 108, s. art. no.–1466. Fulltekst i vitenarkiv
• Valladares, C. E.; Moen, Jøran Idar; Sandholt, Per Even; Denig, W. F. & Troshichev, O. (2002). Simultaneous observations of dayside aurora from Heiss Island and Ny-Ålesund. Geophysical Research Letters. ISSN 0094-8276. 29(24). Fulltekst i vitenarkiv
• Sandholt, Per Even; Farrugia, Charles J.; Moen, Jøran Idar & Denig, W. F. (2002). The cusp in rapid transition. Journal of Geophysical Research (JGR). ISSN 0148-0227. 107. Fulltekst i vitenarkiv
• Sandholt, Per Even; Denig, W. F.; Farrugia, Charles J.; Lybekk, Bjørn & Trondsen, Espen (2002). Auroral structure at the cusp equatorward boundary: Relationship with the electron edge of low-latitude boundary layer precipitation. Journal of Geophysical Research (JGR). ISSN 0148-0227. 107. Fulltekst i vitenarkiv
• Sandholt, Per Even; Farrugia, Charles J.; Lester, M.; Cowley, Stanley W. H.; Milan, Steve & Denig, W. F. [Vis alle 9 forfattere av denne artikkelen] (2002). Multi-stage substorm expansion: Auroral dynamics in relation to plasma sheet particle injection, precipitation, and plasma convection. Journal of Geophysical Research (JGR). ISSN 0148-0227. 107. Fulltekst i vitenarkiv
• Maynard, N. C.; Burke, W. J.; Moen, Jøran Idar; Sandholt, Per Even; Lester, M. & Ober, Dan [Vis alle 8 forfattere av denne artikkelen] (2002). Bifurcation of the cusp: Implications for understanding boundary layers, Earth's Low latitude Boundary Layer. Geophysical Monograph Series. ISSN 0065-8448. s. 219–228. Fulltekst i vitenarkiv
• Sandholt, Per Even & Farrugia, Charles J. (2002). Monitoring magnetosheath-magnetosphere interconnection topology from the aurora. Annales Geophysicae. ISSN 0992-7689. 20, s. 629–637. Fulltekst i vitenarkiv
• Sandholt, Per Even; Farrugia, Charles J.; Cowley, Stanley W. H.; Lester, M. & Cerisier, J.-C. (2001). Excitation of transient lobe cell convection and auroral arc at the cusp poleward boundary during transition of the interplanetary magnetic field from south to north. Annales Geophysicae. ISSN 0992-7689. 19, s. 487–493. Fulltekst i vitenarkiv
• Sandholt, Per Even; Farrugia, Charles J.; Cowley, Stanley W. H. & Lester, M. (2001). Dayside auroral bifurcation sequence during By-dominated interplanetary magnetic field: Relationship with merging and lobe convection cells. Journal of Geophysical Research (JGR). ISSN 0148-0227. 106, s. 15429–15444. Fulltekst i vitenarkiv
• Maynard, N. C.; Burke, W. J.; Sandholt, Per Even; Moen, Jøran Idar; Ober, D. M. & Lester, M. [Vis alle 8 forfattere av denne artikkelen] (2001). Observations of simultaneous effects of merging in both hemispheres. Journal of Geophysical Research (JGR). ISSN 0148-0227. 106, s. 24551–24577. Fulltekst i vitenarkiv
• Moen, Jøran Idar; Sandholt, Per Even & Egeland, Alv (2001). Pre- and post-noon asymmetry in dayside auroral activity and convection related to solar wind-magnetosphere interactions. Advances in Space Research. ISSN 0273-1177. 27, s. 1363–1372. Fulltekst i vitenarkiv
• Moen, Jøran Idar; Carlson, Herbert C; Milan, Steve; Shumilov, N.; Lybekk, Bjørn & Sandholt, Per Even [Vis alle 7 forfattere av denne artikkelen] (2001). On the collocation between dayside auroral activity and coherent HF backscatter. Annales Geophysicae. ISSN 0992-7689. 18, s. 1531–1549. Fulltekst i vitenarkiv Vis sammendrag

  The 2D morphology of coherent HF radar and optical cusp aurora has been studied for conditions of predominantly southward IMF conditions, which favours low-latitude boundary layer reconnection. Despite the variability in shape of radar cusp Doppler spectra, the spectral width criterion of >220 ms-1 proves to be a robust cusp discriminator. For extended periods of well developed radar backscatter echoes, the equatorward boundary of the >220 ms-1 spectral width enhancement lines up remarkably well with the equatorward boundary of the optical cusp aurora. The spectral width boundary is however poorly determined during development and fading of radar cusp backscatter. Closer inspection of radar Doppler profile characteristics suggests that a combination of spectral width and shape may advance boundary layer identification by HF radar. For the two December days studied the onset of radar cusp backscatter occurred within pre-existing 630.0 nm cusp auroral activity and appear to be initiated by sunrise, i.e. favourable radio wave propagation conditions had to develop. Better methods are put forth for analysing optical data, and for physical interpretation of HF radar data, and for combining these data, as applied to detection, tracking, and better understanding of dayside aurora. The broader motivation of this work is to develop wider use by the scientific community, of results of these techniques, to accelerate understanding of dynamic high latitude boundary-processes. The contributions in this work are: 1) improved techniques of analysis of observational data, yielding meaningfully enhanced accuracy for deduced cusp locations; 2) a correspondingly more pronounced validation of correlation of boundary locations derived from the observational data set; and 3) a firmer physical rationale as to why the good correlation observed should theoretically be expected.

• Maynard, N. C.; Burke, W. J.; Sandholt, Per Even; Moen, Jøran Idar; Ober, Dan & Lester, M. [Vis alle 8 forfattere av denne artikkelen] (2001). Observations of simultaneous effects of merging in both hemispheres. Journal of Geophysical Research (JGR). ISSN 0148-0227. 106, s. 24551–24577. Fulltekst i vitenarkiv
• Sandholt, Per Even; Farrugia, Charles J.; Cowley, Stanley W. H.; Lester, M.; Denig, W. F. & Cerisier, J.-C. [Vis alle 10 forfattere av denne artikkelen] (2000). Dynamic cusp aurora and associated pulsed reverse convection during northward interplanetary magnetic field. Journal of Geophysical Research (JGR). ISSN 0148-0227. 105, s. 12869–12894. Fulltekst i vitenarkiv
• Farrugia, Charles J.; Sandholt, Per Even; Maynard, N. C.; Burke, W. J.; Scudder, J. D. & Ober, Dan [Vis alle 8 forfattere av denne artikkelen] (2000). Pulsating mid-morning auroral arcs, filamentation of a mixing region in a flank boundary layer, and ULF pulsations during a POLAR - Svalbard conjunction. Journal of Geophysical Research (JGR). ISSN 0148-0227. 105, s. 27531–27531. Fulltekst i vitenarkiv
• Sandholt, Per Even & Farrugia, Charles J. (1999). On the dynamic cusp aurora and IMF By. Journal of Geophysical Research (JGR). ISSN 0148-0227. 104(A6), s. 12461–12472. Fulltekst i vitenarkiv
• Sandholt, Per Even; Farrugia, Charles J.; Cowley, Stanley W. H.; Denig, W. F.; Lester, M. & Moen, Jøran Idar [Vis alle 7 forfattere av denne artikkelen] (1999). Capture of magnetosheath plasma by the magnetosphere during northward IMF. Geophysical Research Letters. ISSN 0094-8276. 26(18), s. 2833–2836. Fulltekst i vitenarkiv
• Sandholt, Per Even; Farrugia, Charles J. & Lybekk, Bjørn (1999). The dynamic cusp aurora on Nov.30, 1997: Response to southward turning of the IMF. Annales Geophysicae. ISSN 0992-7689. 17, s. 1155–1165. Fulltekst i vitenarkiv
• Milan, Steve; Lester, M.; Cowley, Stanley W. H.; Moen, Jøran Idar; Sandholt, Per Even & Owen, Christine (1999). Meridian-scanning photometer, coherent HF radar, and magnetometer observations of the cusp: a case study. Annales Geophysicae. ISSN 0992-7689. 17, s. 159–172. Fulltekst i vitenarkiv
• Sandholt, Per Even; Farrugia, Charles J.; Cowley, Stanley W. H.; Lester, M.; Moen, Jøran Idar & Lybekk, Bjørn [Vis alle 7 forfattere av denne artikkelen] (1999). Excitation and decay of magnetospheric lobe cell convection and its associated aurora. Geophysical Research Letters. ISSN 0094-8276. 26, s. 3597–3601. Fulltekst i vitenarkiv
• Lyons, L.R.; Koskinen, H.E.J.; Blake, J. B.; Egeland, Alv; Hirahara, M. & Øieroset, Marit [Vis alle 8 forfattere av denne artikkelen] (1999). Processes leading to plasma losses into the high-latitude atmosphere. I Hultqvist, B.; Øieroset, Marit; Paschmann, G. & Treumann, R. (Red.), Space Science Reviews. Kluwer Academic Publishers, Dordrecht, Holland. s. 85–135. Fulltekst i vitenarkiv
• Sandholt, Per Even; Farrugia, Charles J.; Øieroset, Marit; Stauning, P. & Denig, W. F. (1998). Auroral Activity Associated with Unsteady Magnetospheric Erosion: Observations on December 18, 1990. Journal of Geophysical Research (JGR). ISSN 0148-0227. 103, s. 2309–2317. Fulltekst i vitenarkiv

Se alle arbeider i NVA

• Sandholt, Per Even; Carlson, Herbert C & Egeland, Alv (2002). Dayside and Polar Cap Aurora. Kluwer Academic Publishers, Dordrecht, Holland. ISBN 9781402004476. 287 s. Fulltekst i vitenarkiv

Se alle arbeider i NVA

• Sato, Hiroatsu; Pecseli, Hans Laszlo; Trulsen, Jan Karsten; Sandholt, Per Even & Farrugia, C (2023). Impulse-driven oscillations of near-Earth magnetosphere. Fulltekst i vitenarkiv
• Sandholt, Per Even; Farrugia, Charlie & Andalsvik, Yngvild Linnea (2009). Polar cap convection/precipitation states during Earth passage of two ICMEs at minimum of solar cycle 23. Fulltekst i vitenarkiv
• Sandholt, Per Even & Farrugia, Charlie (2008). Plasma Flow Channels at Dawn/Dusk Polar Cap Boundaries: Momentum Transfer on old Open Field Lines and the Roles of IMF By and Conductivity Gradients. Fulltekst i vitenarkiv
• Lund, Eric; Farrugia, Charlie & Sandholt, Per Even (2007). Momentum transfer at the high-latitude magnetopause and boundary layers. Fulltekst i vitenarkiv
• Farrugia, Charlie; Sandholt, Per Even & Sharma, Arvind (2007). Wind - Polar - DMSP Study of Energetic Ion Bursts and Associated Electron Flux Enhancements During Passage of a Magnetic Cloud Sheath. Fulltekst i vitenarkiv
• Sandholt, Per Even (2007). Dayside Aurora in Relation to Solar Wind - Magnetosphere - Ionosphere Coupling. Fulltekst i vitenarkiv
• Sandholt, Per Even; Farrugia, Charlie & Sharma, Arvind (2007). Energetic ion bursts and associated electron flux enhancements during magnetic cloud passage: A WIND - POLAR - DMSP Study. Fulltekst i vitenarkiv
• Sandholt, Per Even; Farrugia, Charlie & Sharma, Arvind (2006). Polar-DMSP observations of enhanced polar rain and ion fluxes on old open flux tubes. Fulltekst i vitenarkiv
• Sandholt, Per Even & Farrugia, Charlie (2006). Response of aurorae, plasma convection and Birkeland currents to strong IMF By and negative Bz conditions. Fulltekst i vitenarkiv
• Farrugia, Charlie & Sandholt, Per Even (2006). Structure of the reconnecting magnetosphere under a strongly eastward-pointing IMF (with Bz < 0): Simultaneous observations in both hemispheres under near-equinox conditions. Fulltekst i vitenarkiv
• Sandholt, Per Even & Farrugia, Charlie (2006). Spatiotemporal structure of the reconnecting magnetosphere. Fulltekst i vitenarkiv
• Sandholt, Per Even & Farrugia, Charlie (2006). Poleward moving auroral forms (PMAFs) revisited: Relationships with plasma convection, field-aligned currents, and the IMF By polarity. Fulltekst i vitenarkiv
• Lund, E. J.; Farrugia, C. J.; Sandholt, Per Even; Raeder, J & Larson, D. J. (2006). High Latitude Magnetosphere - Ionosphere Coupling as Seen by Multiple Spacecraft, Ground-Based Instruments, and Global MHD Models. Fulltekst i vitenarkiv
• Sandholt, Per Even; Farrugia, Charlie & Lund, Eric (2006). Space- and time variations of dayside aurora: Relationships with plasma convection channels and Birkeland currents. Fulltekst i vitenarkiv
• Sandholt, Per Even & Farrugia, Charles J. (2005). Reconnection tailward of the cusp under IMF Bz negative conditions. Fulltekst i vitenarkiv
• Sandholt, Per Even & Farrugia, Charles J. (2005). Magnetosphere-ionosphere coupling initiated at the duskside boundary layer during impulsive IMF rotations. Fulltekst i vitenarkiv
• Pfaff, R.; Steigies, C.; Yeoman, T. K.; Milan, Steve; Lester, M. & Sandholt, Per Even [Vis alle 10 forfattere av denne artikkelen] (2004). Combined sounding rocket and SuperDARN/EISCAT radar observations of plasma convection, shear, irregularities and other phenomena in the cusp and boundary layer during IMF Bz negative and By negative conditions. Fulltekst i vitenarkiv
• Pfaff, R.; Steigies, C.; Acuna, M.; Freudenreich, H.; Yeoman, T. K. & Milan, Steve [Vis alle 23 forfattere av denne artikkelen] (2003). Combined sounding rocket and SuperDARN/EISCAT radar observations of plasma convection, shear, irregularities and other phenomena in the cusp and boundary layer during IMF Bz negative and By negative conditions. Fulltekst i vitenarkiv
• Sandholt, Per Even & Farrugia, Charles J. (2003). Solar ejecta and interplanetary magnetic clouds: Responses in the Earth's magnetosphere and Aurora Borealis. Nordic space activities. ISSN 0805-7397. 11(3), s. 9–10. Fulltekst i vitenarkiv
• Sandholt, Per Even (2002). Multi-instrument studies of cusp structure and dynamics as a function of IMF orientation. Fulltekst i vitenarkiv
• Farrugia, Charles J.; Sandholt, Per Even; Scudder, J. D.; Russell, C. T. & Torbert, R. B. (2002). Distant observations of pulsed reconnection signatures in the cusp, and cusp structure, using ground and space observations. Fulltekst i vitenarkiv
• Sandholt, Per Even & Farrugia, Charles J. (2002). The aurora as monitor of magnetospheric boundary layer processes. Fulltekst i vitenarkiv
• Deehr, C. S.; Sandholt, Per Even; Arnoldy, R.; Kintner, P.; Sigernes, F. & Lorentzen, D. (2002). Magnetospheric boundaries from sounding rocket and ground-based observations in the mid-morning aurora. Fulltekst i vitenarkiv
• Sandholt, Per Even (2001). Nordlyset - En "dans" av elektriske strømmer i atmosfæren. Astronomi. ISSN 0802-7587. 31, s. 24–27. Fulltekst i vitenarkiv

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