Search Publications

The Properties of Two Low-redshift O VI Absorbers and Their Associated Galaxies toward 3c 263

Savage, B. D.; Narayanan, A.; Wakker, B. P. +4 more

Ultraviolet observations of the QSO 3C 263 (z _em = 0.652) with Cosmic Origins Spectrograph and FUSE reveal O VI absorption systems at z = 0.06342 and 0.14072. WIYN multi-object spectrograph observations provide information about the galaxies associated with the absorbers. The multi-phase system at z = 0.06342 traces cool photoionized ga…

Systematic Motion of Fine-scale Jets and Successive Reconnection in Solar Chromospheric Anemone Jet Observed with the Solar Optical Telescope/Hinode

Shibata, K.; Isobe, H.; Singh, K. A. P. +1 more

The Solar Optical Telescope (SOT) on board Hinode allows observations with high spatiotemporal resolution and stable image quality. A λ-shaped chromospheric anemone jet was observed in high resolution with SOT/Hinode. We found that several fine-scale jets were launched from one end of the footpoint to the other. These fine-scale jets (~1.5-2.5 Mm)…

The near-IR counterpart of IGR J17480-2446 in Terzan 5

D'Antona, F.; Ventura, P.; Papitto, A. +8 more

Context. Some globular clusters in our Galaxy are noticeably rich in low-mass X-ray binaries. Terzan 5 has the richest population among globular clusters of X- and radio-pulsars and low-mass X-ray binaries.
Aims: The detection and study of optical/IR counterparts of low-mass X-ray binaries is fundamental to characterizing b…

Temporal evolution and electric potential structure of the auroral acceleration region from multispacecraft measurements

Dandouras, I.; Lucek, E.; Fazakerley, A. N. +12 more

Bright aurorae can be excited by the acceleration of electrons into the atmosphere in violation of ideal magnetohydrodynamics. Modeling studies predict that the accelerating electric potential consists of electric double layers at the boundaries of an acceleration region but observations suggest that particle acceleration occurs throughout this re…

A multiwavelength study of the supernova remnant G296.8-0.3

Combi, J. A.; Martí, J.; Muñoz-Arjonilla, A. J. +3 more

We report XMM-Newton observations of the Galactic supernova remnant G296.8-0.3, together with complementary radio and infrared data. The spatial and spectral properties of the X-ray emission, detected towards G296.8-0.3, was investigated in order to explore the possible evolutionary scenarios and the physical connexion with its unusual morphology …

Gamma-ray burst observations by Fermi Large Area Telescope revisited: new candidates found

Pshirkov, M. S.; Rubtsov, G. I.; Tinyakov, P. G.

We search the Fermi Large Area Telescope (LAT) photon data base for an extended gamma-ray emission which could be associated with any of the 581 previously detected gamma-ray bursts (GRBs) visible to the Fermi-LAT. For this purpose, we compare the number of photons with energies E > 100 MeV and E > 1 GeV which arrived in the first 1500 s aft…

Cases and statistical study on Hot Flow Anomalies with Cluster spacecraft data

Zhang, H.; Wang, S.; Zong, Q. G.

Observations from SDO, Hinode, and STEREO of a Twisting and Writhing Start to a Solar-filament-eruption Cascade

Hara, Hirohisa; Moore, Ronald L.; Sterling, Alphonse C.

We analyze data from SDO (AIA, HMI), Hinode (SOT, XRT, EIS), and STEREO (EUVI) of a solar eruption sequence of 2011 June 1 near 16:00 UT, with an emphasis on the early evolution toward eruption. Ultimately, the sequence consisted of three emission bursts and two filament ejections. SDO/AIA 304 Å images show absorbing-material strands initially in …

Hot Diffuse Emission in the Nuclear Starburst Region of NGC 2903

Soria, Roberto; Tennant, Allyn F.; Swartz, Douglas A. +2 more

We present a deep Chandra observation of the central regions of the late-type barred spiral galaxy NGC 2903. The Chandra data reveal soft (kT_e ~ 0.2-0.5 keV) diffuse emission in the nuclear starburst region and extending ~2' (~5 kpc) to the north and west of the nucleus. Much of this soft hot gas is likely to be from local active star-f…

A Method of Identifying AGNs Based on Emission-Line Excess and the Nature of Low-Luminosity AGNs in the Sloan Digital Sky Survey. I. A New Method

Tanaka, Masayuki

We developed a new technique for identifying active galactic nuclei (AGNs) and studied the nature of low-luminosity AGNs in the Sloan Digital Sky Survey. This is the former part of a series of papers. We develop a new, sensitive method of identifying AGNs in this paper. The emission-line luminosity in a spectrum is the sum of a star-formation comp…