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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…
The application of slim disk models to ULX: The case of M33 X-8
Cappelluti, N.; Grandi, P.; Rodriguez, J. +8 more
A comparative XMM-Newton archival data spectral study of the ultraluminous X-ray source (ULX) M33 X-8 has been performed by using both the standard disk model and the newly developed slim disk models. The results of this analysis tend to confirm the hypothesis that M33 X-8 is an X-ray binary with a stellar-mass black hole accreting at super-Edding…
Mapping sub-pixel surface roughness on Mars using high-resolution satellite image data
Gillespie, Alan R.; Mushkin, Amit
The ratio between co-registered pixels in stereo or repeat image pairs is used to constrain the deviation of the Martian surface from Lambertian reflection due to unresolved shadows at the pixel scale of orbiting imagers. Relative differences between the ratios primarily reflect differences in the effective amount of shadows `seen' by the sensor i…
Possibility of Excitation of Low-ℓ P-Modes by Energetic Solar Transients
Antia, H. M.; Ambastha, Ashok
We examine the temporal variation of power in low-ℓ modes using GONG data for the period of May 1995-October 2005 and compare this with disk-integrated flare and CME indices. A poor correlation between the running means of Flare Index and mode power is found. A similar result is found for CME Index also. Variations in the running mean mode power c…