Search Publications
Thermal X-Ray Emission from Shocked Ejecta in Type Ia Supernova Remnants. II. Parameters Affecting the Spectrum
Badenes, Carles; Borkowski, Kazimierz J.; Bravo, Eduardo
The supernova remnants (SNRs) left behind by Type Ia supernovae (SNe) provide an excellent opportunity for the study of these enigmatic objects. In a previous work we showed that it is possible to use the X-ray spectra of young Type Ia SNRs to explore the physics of Type Ia SNe and identify the relevant mechanism underlying these explosions. Our s…
Thermal Dust Emission from Proplyds, Unresolved Disks, and Shocks in the Orion Nebula
Smith, Nathan; Bally, John; Kassis, Marc +2 more
We present a new 11.7 µm mosaic image of the inner Orion Nebula obtained with the T-ReCS instrument on Gemini South. The map covers 2.7 arcmin 7×1.6 arcmin, with a diffraction-limited spatial resolution of 0.35" it includes the BN/KL region, the Trapezium, and OMC-1 South. Excluding BN/KL, we detect 91 thermal-IR point sources, with 27 known…
Nine Years Of Euv Bright Points
McIntosh, Scott W.; Gurman, Joseph B.
We discuss early results derived from an algorithm that automates the detection, cataloging, and analysis of extreme-ultraviolet (EUV) "bright points" (BP) from 9 years of data acquired by the Extreme-ultraviolet Imaging Telescope (EIT) on the Solar and Heliospheric Observatory (SOHO). The algorithm relies upon the computation of a map of "intensi…
The Fading of Transient Anomalous X-Ray Pulsar XTE J1810-197
Gotthelf, E. V.; Halpern, J. P.
Three observations of the 5.54 s transient anomalous X-ray pulsar XTE J1810-197 obtained over 6 months with the Newton X-ray Multi-Mirror (XMM-Newton) mission are used to study its spectrum and pulsed light curve as the source fades from outburst. The decay is consistent with an exponential of time constant ~300 days but not a power law as predict…
The giant Hα/X-ray filament in the cluster of galaxies A1795
Fabian, A. C.; Sanders, J. S.; Crawford, C. S.
The cluster of galaxies A1795 hosts a 46 kpc long filament at its core, which is clearly visible in the light of Hα and X-ray emission. We present optical slit spectroscopy and deeper Chandra X-ray data of the filament. The optical spectra reveal that the bulk of the filament is quiescent (with σ < 130 km s-1), although considerable …
The mass of the black hole in 3C 273
Paltani, S.; Türler, M.
In this paper we apply the reverberation method to determine the mass of the black hole in 3C 273 from the Lyα and Civ emission lines using archival IUE observations. Following the standard assumptions of the method, we find a maximum-likelihood estimate of the mass of 6.59× 10^9 M_⊙, with a 1σ confidence interval 5.69{-}8.27× 109 M_⊙. …
Forecast evaluation of the coronal mass ejection (CME) geoeffectiveness using halo CMEs from 1997 to 2003
Cho, K. -S.; Kim, Y. -H.; Moon, Y. -J. +5 more
In this study we have made a forecast evaluation of geoeffective coronal mass ejections (CMEs) by using frontside halo CMEs and the magnetospheric ring current index, Dst. This is the first time, to our knowledge, that an attempt has been made to construct contingency tables depending on the geoeffectiveness criteria as well as to estimate the pro…
A Chandra and XMM-Newton study of the wide-angle tail radio galaxy 3C465
Hardcastle, M. J.; Worrall, D. M.; Sakelliou, I.
We have observed the prototypical wide-angle tail (WAT) radio galaxy 3C465 with Chandra and XMM-Newton. X-ray emission is detected from the active nucleus and the inner radio jet, as well as a small-scale, cool component of thermal emission, a number of the individual galaxies of the host cluster (Abell 2634), and the hotter thermal emission from …
A Coherent Timing Solution for the Nearby Isolated Neutron Star RX J1308.6+2127/RBS 1223
van Kerkwijk, M. H.; Kaplan, D. L.
We present a phase-connected timing solution for the nearby isolated neutron star RX J1308.6+2127 (RBS 1223). From dedicated Chandra observations as well as archival Chandra and XMM-Newton data spanning a period of 5 years, we demonstrate that the 10.31 s pulsations are slowing down steadily at a rate of P˙=1.120(3)×10-13 s s-1
HST/ACS observations of the old and metal-poor Sagittarius dwarf irregular galaxy
Gullieuszik, M.; Momany, Y.; Clemens, M. +6 more
We have obtained deep color-magnitude diagrams (CMDs) of the Sagittarius dwarf irregular galaxy with the Advanced Camera for Surveys (ACS) on board the Hubble Space Telescope. The new diagrams show for the first time the star formation history of SagDIG. The young main-sequence is traced down to mF606W ≃27.5, well separated from the old…