Search Publications
The Deep Look at the Hard X-Ray Sky: The Swift-INTEGRAL X-Ray (SIX) Survey
Greiner, Jochen; Ajello, Marco; Bottacini, Eugenio
The supermassive black holes at the center of active galactic nuclei (AGNs) are surrounded by obscuring matter that can block nuclear radiation. Depending on the amount of blocked radiation, the flux from the AGN can be too faint to be detected by currently flying hard X-ray (above 15 keV) missions. At these energies only ~1% of the intensity of t…
Alessi 95 and the short-period Cepheid SU Cassiopeiae
Gieren, W. P.; Alessi, B.; Storm, J. +6 more
The parameters for the newly discovered open cluster Alessi 95 are established on the basis of available photometric and spectroscopic data, in conjunction with new observations. Colour excesses for spectroscopically observed B- and A-type stars near SU Cas follow a reddening relation described by E(U-B)/E(B-V) = 0.83 + 0.02E(B-V), implying a valu…
Observations of HCl altitude dependence and temporal variation in the 70-100 km mesosphere of Venus
Clancy, R. Todd; Sandor, Brad J.
Spectroscopically resolved observations of the 625.9 GHz H35Cl absorption lines were obtained with the James Clerk Maxwell Telescope on October 23, November 7, and December 5, 2010. The nightside atmosphere was observed on all three dates, and the dayside morning crescent was also observed on December 5. Shape of the pressure-broadened …
Scientific Analysis within SEPServer - New Perspectives in Solar Energetic Particle Research: The Case Study of the 13 July 2005 Event
Vainio, R.; Valtonen, E.; Riihonen, E. +19 more
Solar energetic particle (SEP) events are a key ingredient of solar-terrestrial physics both for fundamental research and space weather applications. Multi-satellite observations are an important and incompletely exploited tool for studying the acceleration and the coronal and interplanetary propagation of the particles. While STEREO uses for this…
A comprehensive study of RXTE and INTEGRAL observations of the X-ray pulsar 4U 1907+09
Şahiner, Ş.; Baykal, A.; Inam, S. Ç.
We analyse observations of the accretion-powered pulsar 4U 1907+09 from the International Gamma-Ray Astrophysics Laboratory (INTEGRAL; between 2005 October and 2007 November) and from the Rossi X-ray Timing Explorer (RXTE; between 2007 June and 2011 March). Using observations from the Imager on-board the INTEGRAL satellite (IBIS), the INTEGRAL Sof…
Optical and Infrared Analysis of Type II SN 2006bc
Barlow, M. J.; Clayton, Geoffrey C.; Meixner, M. +8 more
We present nebular phase optical imaging and spectroscopy and near/mid-IR imaging of the Type II SN 2006bc. Observations reveal the central wavelength of the symmetric Hα line profile to be redshifted with respect to the host galaxy Hα emission by day 325. Such a phenomenon has been argued to result from an asymmetric explosion in the iron-peak el…
Brightness and Fluctuation of the Mid-infrared Sky from AKARI Observations toward the North Ecliptic Pole
Jeong, Woong-Seob; Matsuura, Shuji; Matsumoto, Toshio +1 more
We present the smoothness of the mid-infrared sky from observations by the Japanese infrared astronomical satellite AKARI. AKARI monitored the north ecliptic pole (NEP) during its cold phase with nine wave bands covering from 2.4 to 24 µm, out of which six mid-infrared bands were used in this study. We applied power-spectrum analysis to the …
Extended Magnetospheres in Pre-main-sequence Evolution: From T Tauri Stars to the Brown Dwarf Limit
Gómez de Castro, Ana I.; Marcos-Arenal, Pablo
Low-mass pre-main-sequence stars, i.e., T Tauri stars (TTSs), strongly radiate at high energies, from X-rays to the ultraviolet (UV). This excess radiation with respect to main-sequence cool stars (MSCSs) is associated with the accretion process, i.e., it is produced in the extended magnetospheres, in the accretion shocks on the stellar surface, a…
Identification of electron field-aligned current systems in Saturn's magnetosphere
Schippers, P.; André, N.; Gurnett, D. A. +3 more
Based on the analysis of 7 years of Cassini electron plasma spectrometer data near Saturn's equatorial plane, we computed the average directional electron current in the Northern and the Southern hemispheres separately. We determined the net current density by subtracting the downward electron current density (equator to the ionosphere) from the u…
Wide-field Survey of Emission-line Stars in IC 1396
Ishihara, D.; Ueno, M.; Watanabe, M. +3 more
We have made an extensive survey of emission-line stars in the IC 1396 H II region to investigate the low-mass population of pre-main-sequence (PMS) stars. A total of 639 Hα emission-line stars were detected in an area of 4.2 deg2 and their i' photometry was measured. Their spatial distribution exhibits several aggregates near the eleph…