Search Publications
Identification of four RXTE Slew Survey sources with nearby luminous active galactic nuclei
Revnivtsev, M.; Sazonov, S.; Churazov, E. +1 more
Based on RXTE scans and observations with the SWIFT/XRT telescope and INTEGRAL observatory, we report the identification of four X-ray sources discovered during the RXTE Slew Survey of the |b|>10° sky with nearby (z∼0.017-0.098) luminous (L2-10~keV∼ 5× 1042-1044 erg s-1) active galactic nuclei. Two of…
Correlated X-ray spectral and timing variability of the Be/X-ray binary V0332+53/BQ Camelopardalis during a type II outburst
Reig, P.; Martínez-Núñez, S.; Reglero, V.
Context: .After more than 15 years of quiescence the Be/X-ray binary V0332+53 underwent a giant outburst in December 2004.Aims.We have investigated the timing properties of the source in correlation with its spectral states as defined by different positions in the colour-colour diagram. Methods.We have used RXTE and INTEGRAL light curves to obtain…
Central regions of the early-type galaxies in the NGC 3169 group
Sil'chenko, O. K.; Afanasiev, V. L.
We have investigated the central regions of the galaxies in the NGC 3169/NGC 3166/NGC 3156 group with the multipupil fiber spectrograph of the 6-m telescope; the first (central) galaxy in the group is a spiral (Sa) one and the other two galaxies are lenticular ones. The group is known to have an extended HI cloud with a size of more than 100 kpc t…
Probing for evolutionary links between local ULIRGs and QSOs using NIR spectroscopy
Lutz, D.; Genzel, R.; Tacconi, L. J. +6 more
We present a study of the dynamical evolution of ultraluminous infrared galaxies (ULIRGs), merging galaxies of infrared luminosity >1012 L⊙. During our very large telescope large program, we have obtained ISAAC near-infrared, high-resolution spectra of 54 ULIRGs (at several merger phases) and 12 local Palomar-Green QSOs, t…
On the behavior of O+5 in coronal holes: Importance of sunward propagating waves
Hollweg, Joseph V.
The high thermal anisotropy of O+5 in coronal holes, as observed by the Ultraviolet Coronagraph Spectrometer (UVCS) on the Solar and Heliospheric Observatory (SOHO), suggests that these ions are being heated by the cyclotron resonance. The observations indicate that the O+5 temperature steadily increases from r ≈ 1.5 rS<…
Effects of nonlinearity on the structure of PSBL beamlets
Zelenyi, L. M.; Ashour-Abdalla, M.; Dolgonosov, M. S. +1 more
We investigate the nonlinear influence of the cross-tail currents carried by beamlets (substructures of PSBL ion beams) on the topology of the magnetic field, and, correspondingly, on the dispersion properties of these substructures self-consistently generated in this field. We found that some of the peculiarities of beamlet shapes found recently …
Magnetic Structures of Solar Active Regions, Full-Halo Coronal Mass Ejections, and Geomagnetic Storms
Liu, Y.; Webb, D. F.; Zhao, X. P.
We have analyzed three active regions to investigate the relationship between magnetic configurations of active regions and geomagnetic storms. Each active region was associated with multiple full-halo coronal mass ejections (CMEs). This study demonstrates that, although full-halo CMEs may originate from the same active region, it is not necessary…
The Tully-Fisher Relation in Cluster Cl 0024+1654 at z=0.4
Koo, David C.; Simard, Luc; Phillips, Andrew C. +1 more
Using moderate-resolution Keck spectra, we have examined the velocity profiles of 15 members of cluster Cl 0024+1654 at z=0.4. WFPC2 images of the cluster members have been used to determine structural parameters, including disk sizes, orientations, and inclinations. We compare two methods of optical rotation curve analysis for kinematic measureme…
On temperature and abundance effects during an X-ray flare on σ Geminorum
Nordon, R.; Güdel, M.; Behar, E.
We compare quiescent and flare X-ray spectra of the RS CVn binary σ Gem obtained with the Chandra and XMM-Newton grating spectrometers. We find that in addition to an overall 25% flux increase, which can be ascribed to variations in the system's quiescence activity over the 15 months that passed between the observations, there is a hot plasma comp…
A Study of H2 Emission in the Bipolar Proto-Planetary Nebula IRAS 17150-3224
Kwok, Sun; Hrivnak, Bruce J.; Su, Kate Y. L. +2 more
H2 emission has been detected in the bipolar proto-planetary nebula IRAS 17150-3224 from the 1-0 S(1), 1-0 S(0), and 2-1 S(1) transitions in the 2 µm region. Line ratios suggest that this emission is due to collisional excitation. High-resolution imaging with NICMOS on HST shows that the emission comes from four regions: clumps ne…