Search Publications
Observations of the Magnetic Reconnection Signature of an M2 Flare on 2000 March 23
Zhang, Jun; Li, Leping
Multiwavelength observations of an M 2.0 flare event on 2000 March 23 in the NOAA active region 8910 provide us a good chance to study the detailed structure and dynamics of the magnetic reconnection region. In the process of the flare, extreme-ultraviolet (EUV) loops displayed two types of sideward motions upon a loop-top hard X-ray source with a…
High energy variability of 3C 273 during the AGILE multiwavelength campaign of December 2007-January 2008
Caraveo, P. A.; Antonelli, L. A.; Costa, E. +52 more
Context: We report the results of a 3-week multi-wavelength campaign targeting the flat spectrum radio quasar 3C 273 carried out with the AGILE gamma-ray mission, covering the 30 MeV-50 GeV and 18-60 keV, the REM observatory (covering the near-IR and optical), Swift (near-UV/Optical, 0.2-10 keV and 15-50 keV), INTEGRAL (3-200 keV) and Rossi XTE (2…
Hard X-Ray Spectrum from West Lobe of Radio Galaxy Fornax A Observed with Suzaku
Tashiro, M. S.; Seta, H.; Isobe, N. +2 more
An observation of the West lobe of radio galaxy Fornax A (NGC 1316) with Suzaku is reported. Since Feigelson et al. (1995) and Kaneda et al. (1995) discovered the cosmic microwave background boosted inverse-Comptonized (IC) X-rays from the radio lobe, the magnetic field and electron energy density in the lobes have been estimated under the assumpt…
VLT/NACO coronagraphic observations of fine structures in the disk of β Pictoris
Augereau, J. -C.; Pantin, E.; Boccaletti, A. +2 more
Aims: We present ground-based observations of the disk around the A-type star β Pictoris to obtain scattered light images at the highest angular resolution (60 mas, equivalent to about 1 AU at the distance of the star) and the highest contrast in the very close environment of the star. The purpose of this program is to perform a close inspection o…
Low-Power Radio Galaxies in the Distant Universe: A Search for FR I at 1 < z < 2 in the Cosmos Field
Sparks, W. B.; Chiaberge, Marco; Tremblay, Grant +3 more
We present a search for FR I radio galaxies between 1 < z < 2 in the COSMOS field. In absence of spectroscopic redshift measurements, the selection method is based on multiple steps which make use of both radio and optical constraints. The basic assumptions are that (1) the break in radio power between low-power FR Is and the more powerful F…
Is the Martian water table hidden from radar view?
Gurnett, D. A.; Farrell, W. M.; Plaut, J. J. +4 more
Mars may possess a global sub-surface groundwater table as an integral part of its current hydrological system. However, the Mars Advanced Radar for Subsurface and Ionospheric Sounding (MARSIS) onboard the Mars Express (MEx) spacecraft has yet to make a definitive detection of such a body of liquid water. In this work, we quantify the conditions t…
Mesoscale dynamics on the Sun's surface from HINODE observations
Roudier, Th.; Malherbe, J. M.; Meunier, N. +5 more
Context:
Aims: The interactions of velocity scales on the Sun's surface, from granulation to supergranulation are still not understood, nor are their interaction with magnetic fields. We thus aim at giving a better description of dynamics in the mesoscale range which lies between the two scales mentioned above.
Methods: We analyse a 48 h h…
Stochastic and direct acceleration mechanisms in the Earth's magnetotail
Perri, S.; Zimbardo, G.; Greco, A.
Ion beams with energies of the order of several tens of keV are frequently observed in the Earth's magnetotail. Here we consider two possible acceleration mechanisms, the cross tail electric field E y and the stochastic acceleration due to the electromagnetic fluctuations present in the magnetotail. Electromagnetic perturbations are g…
Structures of Local Galaxies Compared to High-Redshift Star-Forming Galaxies
Gardner, Jonathan P.; Smith, Linda J.; Lotz, Jennifer M. +4 more
The rest-frame far-ultraviolet morphologies of eight nearby interacting and starburst galaxies (Arp 269, M 82, Mrk 8, NGC 520, NGC 1068, NGC 3079, NGC 3310, and NGC 7673) are compared with 54 galaxies at z ~ 1.5 and 46 galaxies at z ~ 4 observed in the Great Observatories Origins Deep Survey (GOODS) taken with the Advanced Camera for Surveys onboa…
On the triggering of auroral substorms by northward turnings of the interplanetary magnetic field
Wild, J. A.; Woodfield, E. E.; Morley, S. K.
Some studies over the last decade have indicated that the instability responsible for substorm expansion phase onset may require an external trigger such as a northward turning of the interplanetary magnetic field (IMF). Statistical investigations have lead to contrasting interpretations regarding the relationship between proposed solar wind trigg…