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Chandra High Energy Transmission Grating Spectrometer observations of the supernova remnant 1E0102.2-7219 in the Small Magellanic Cloud reveal a spectrum dominated by X-ray emission lines from hydrogen-like and helium-like ions of oxygen,…

We present Chandra observations of the X-ray environment of a sample of 6 BL Lacertae objects. The improved sensitivity of the ACIS experiment allows us to separate the core X-ray emission from the contribution of diffuse emission from the…

Astrophysics · Physics 2009-11-07 D. Donato , M. Gliozzi , R. M. Sambruna , J. E. Pesce

We report on a recent Chandra ACIS-S observation of the Circinus galaxy. These observations confirm that the nuclear spectrum results from reflection of a hard X-ray continuum by ``neutral'' matter. The nuclear X-ray emission is extended by…

Astrophysics · Physics 2009-11-06 David A. Smith , Andrew S. Wilson

We present the first high resolution photospheric X-ray spectrum of a Supersoft X-ray Source, the famous CAL~83 in the Large Magellanic Cloud. The spectrum was obtained with the Reflection Grating Spectrometer on XMM-Newton during the…

We report results of an 18 ks exposure with the ACIS instrument on Chandra of the powerful z = 0.62 radio galaxy 3C 220.1. The X-ray emission separates into cluster gas of emission-weighted kT ~ 5 keV and 0.7-12 keV luminosity (to a radius…

Astrophysics · Physics 2009-11-06 D. M. Worrall , M. Birkinshaw , M. J. Hardcastle , C. R. Lawrence

We report the discovery of eight X-ray sources with periodic variability in 487 ks of observations of the Galactic center with Chandra. The sources are identified from a sample of 285 objects detected with 100-4200 net counts. Their periods…

Astrophysics · Physics 2009-11-10 M. P. Muno , F. K. Baganoff , M. W. Bautz , W. N. Brandt , G. P. Garmire , G. R. Ricker , ;

We have been monitoring Supernova (SN) 1987A with {\it Chandra X-Ray Observatory} since 1999. We present a review of previous results from our {\it Chandra} observations, and some preliminary results from new {\it Chandra} data obtained in…

We report on a Chandra line spectrum observation of the O supergiant, Zeta Orionis (O9.7 Ib). A 73.4 ks HETGS observation shows a wide range of ionization stages and line strengths over the wavelength range of 5 to 26 A. The observed…

Astrophysics · Physics 2009-10-31 Wayne L. Waldron , Joseph P. Cassinelli

On January 10 and 13, 2001, Venus was observed for the first time with an X-ray astronomy satellite. The observation, performed with the ACIS-I and LETG/ACIS-S instruments on Chandra, yielded data of high spatial, spectral, and temporal…

Astrophysics · Physics 2009-11-07 K. Dennerl , V. Burwitz , J. Englhauser , C. Lisse , S. Wolk

We present radio imaging observations of the 1998 outburst of the peculiar emission line star CI Cam, taken about 1, 4, 75, 82, 93, 163, and 306 days after the beginning of the 31.64 March 1998 X-ray flare. The first two epochs show a…

Astrophysics · Physics 2009-11-10 Amy J. Mioduszewski , Michael P. Rupen

Chandra ACIS-I data of the molecular cloud and HII region complex NGC 6334 were analyzed. The hard X-ray clumps detected with ASCA (Sekimoto et al. 2000) were resolved into 792 point sources. After removing the point sources, an extended…

Pulsar wind nebulae (PWNe) studies with the Chandra X-ray Observatory have opened a new window to address the physics of pulsar winds, zoom on their interaction with their hosting supernova remnant (SNR) and interstellar medium, and…

High Energy Astrophysical Phenomena · Physics 2015-06-16 H. Matheson , S. Safi-Harb , R. Kothes

On January 10 and 13, 2001, Venus was observed for the first time with an X-ray astronomy satellite. The observation, performed with the ACIS-I and LETG/ACIS-S instruments on Chandra, yielded data of high spatial, spectral, and temporal…

Astrophysics · Physics 2007-05-23 K. Dennerl , V. Burwitz , J. Englhauser , C. Lisse , S. Wolk

We present the first X-ray analysis of the diffuse hot ionized gas and the point sources in IC131, after NGC604 the second most X-ray luminous giant HII region in M33. The X-ray emission is detected only in the south eastern part of IC131…

We present Chandra X-ray (0.2-8 keV) and Very Large Array radio (15 and 5 GHz) images of the $\gamma$-ray bright, superluminal quasar 0827+243. The X-ray jet bends sharply--by ~90 deg., presumably amplified by projection effects--5'' from…

Astrophysics · Physics 2009-11-10 Svetlana Jorstad , Alan Marscher

We present Chandra and XMM-Newton observations of the composite star-forming/Seyfert galaxy IRAS20051-1117. The X-ray imaging and spectral properties reveal the presence of an active nucleus. The Chandra image shows a strong nuclear point…

Astrophysics · Physics 2009-11-10 I. Georgantopoulos , I. Papadakis , A. Zezas , M. J. Ward

We present the X-ray properties of a sample of 17 radio sources observed with the Chandra X-ray Observatory as part of a project aimed at studying the X-ray emission from their radio jets. In this paper, we concentrate on the X-ray…

We present an 82 ksec Chandra ACIS-I observation of a large-scale hierarchical complex, which consists of various clusters/groups of galaxies and low-surface brightness X-ray emission at z = 0.247. This high-resolution {\sl Chandra}…

Astrophysics · Physics 2009-11-10 Q. Daniel Wang , Frazer Owen , Michael Ledlow

An analysis of a 29 ksec Chandra ACIS-S observation of the young, Cassiopeia-A like supernova remnant in the irregular galaxy NGC 4449 is presented. The observed 0.5-2.1 keV spectrum reveals the likely presence of several emission lines…

Astrophysics · Physics 2009-11-07 D. J. Patnaude , R. A. Fesen

We present the results of an archival 54 ks long Chandra observation of the peculiar source Cir X--1 during the phase passage 0.223-0.261. A comparative analysis of X-ray spectra, selected at different flux levels of the source, allows us…

Astrophysics · Physics 2009-06-23 A. D'Ai , R. Iaria , T. Di Salvo , G. Lavagetto , N. R. Robba