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We present a detailed analysis of Chandra X-ray observations of the lensing cluster of galaxies CL0024+17 at z=0.395. We found that the radial temperature profile is consistent with being isothermal out to ~600 kpc and that the average…

Astrophysics · Physics 2009-11-10 Naomi Ota , Etienne Pointecouteau , Makoto Hattori , Kazuhisa Mitsuda

The scattering diameters of Sgr A* and several nearby OH masers (~ 1" at 1 GHz) indicate that a region of enhanced scattering is along the line of sight to the Galactic center. We combine radio-wave scattering data and free-free emission…

Astrophysics · Physics 2009-10-30 T. Joseph W. Lazio , James M. Cordes

We report preliminary results from an arcsecond-resolution X-ray survey of nearby galaxies using ACIS on board Chandra. The total sample consists of 41 low-luminosity AGNs, including Seyferts, LINERs, and LINER/H II transition objects. In…

The Galactic plane is a strong hard x-ray emitter and the emission forms a narrow continuous ridge. The currently known hard x-ray sources are far too few to explain the ridge x-ray emission, and the fundamental question as to whether the…

Astrophysics · Physics 2009-11-07 Ken Ebisawa , Yoshitomo Maeda , Hidehiro Kaneda , Shigeo Yamauchi

We have observed the Galactic Center (GC) region at 0.154 and 0.255 GHz with the GMRT. A total of 62 compact likely extragalactic sources are detected. Their scattering sizes go down linearly with increasing angular distance from the GC up…

Astrophysics of Galaxies · Physics 2015-06-16 Subhashis Roy

We present an analysis of a recent XMM-Newton observation of Sgr A East, a supernova remnant located close to the Galactic Centre. Very high quality X-ray spectra reveal many emission lines from highly ionized atoms consistent with a…

Astrophysics · Physics 2009-11-10 Masaaki Sakano , Robert S. Warwick , Anne Decourchelle , Peter Predehl

We identify the radio-emitting shell-type supernova remnant G15.9+0.2 as a relatively young remnant containing an X-ray point source that may be its associated neutron star. The integrated spectrum of the remnant shell obtained from our 30…

Astrophysics · Physics 2009-11-11 S. P. Reynolds , K. J. Borkowski , U. Hwang , I. Harrus , R. Petre , G. Dubner

The results from a recent Chandra ACIS-S study of the cluster surrounding Cygnus A are presented. We have deprojected the X-ray spectra taken from various elliptical shells in order to derive the run of temperature, density, pressure, and…

X-ray data of the Centaurus cluster, obtained with {\it XMM-Newton} for 45 ksec, were analyzed. Deprojected EPIC spectra from concentric thin shell regions were reproduced equally well by a single-phase plasma emission model, or by a…

Cosmology and Nongalactic Astrophysics · Physics 2009-08-11 I. Takahashi , M. Kawaharada , K. Makishima , K. Matsushita , Y. Fukazawa , Y. Ikebe , T. Kitaguchi , M. Kokubun , K. Nakazawa , S. Okuyama , N. Ota , T. Tamura

Recently, unresolved hard (20-40 keV) X-ray emission has been discovered within the central 10 pc of the Galaxy, possibly indicating a large population of intermediate polars (IPs). Chandra and XMM-Newton measurements in the surrounding ~50…

The imaging atmospheric Cherenkov array H.E.S.S. recently discovered an extended source in the 0.4$-$10 TeV energy range, HESS J1303-631. We obtained a 5 ks observation with the ACIS-I array on the Chandra X-ray observatory that does not…

Astrophysics · Physics 2009-11-11 R. Mukherjee , J. P. Halpern

The nearby galaxy M33 hosts the most luminous steady X-ray source in the Local Group. The high spatial resolution of Chandra allows us to confirm that this ultra-luminous X-ray source is within the nucleus and rule out at the 4.6 sigma…

Astrophysics · Physics 2009-11-07 Guillaume Dubus , Robert E. Rutledge

We report on the diffuse X-ray emissions from the Galactic center (GCDX) observed with the X-ray Imaging Spectrometer (XIS) on board the Suzaku satellite. The highly accurate energy calibrations and extremely low background of the XIS…

Astrophysics · Physics 2009-11-13 K. Koyama , Y. Hyodo , T. Inui , M. Nobukawa , H. Mori

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 first detailed imaging and spatially resolved spectroscopic study of the Galactic supernova remnant G292.2-0.5, associated with the high-magnetic field radio pulsar J1119-6127, using Chandra and XMM-Newton. The…

High Energy Astrophysical Phenomena · Physics 2015-06-05 Harsha S. Kumar , Samar Safi-Harb , Marjorie Gonzalez

We report the detection of a point source CXO J172337.5-373442 in a Chandra field with a high significance (26.7 sigma), and the discovery (4 sigma) of a 48" long X-ray tail emanating from the point source. The X-ray spectra of both the…

Astrophysics · Physics 2009-11-13 Sudip Bhattacharyya

We report the detection of six discrete, low-luminosity (Lx < 10^33 erg/s) X-ray sources, located within 12 arcsec of the center of the collapsed-core globular cluster M30 (NGC 7099), and a total of 13 sources within the half-mass radius,…

We study the properties of hot gaseous halos in 10 nearby ultraluminous IRAS galaxies observed with the ACIS instrument on board Chandra. For all sample galaxies, diffuse soft X-ray emissions are found within ~10 kpc of the central region;…

Astrophysics · Physics 2008-11-26 Z. Y. Huo , X. Y. Xia , S. J. Xue , S. Mao , Z. G. Deng

[abridged] We investigate the nature of the luminous X-ray source population detected in a (72 ks) Chandra ACIS-S observation of NGC 4038/39, the Antennae galaxies. We derive the average X-ray spectral properties of sources in different…

Astrophysics · Physics 2017-11-29 A. Zezas , G. Fabbiano , A. H. Rots , S. S. Murray

We present Chandra/ACIS images of several high-mass star-forming regions. The massive stellar clusters powering these HII regions are resolved at the arcsecond level into hundreds of stellar sources, similar to those seen in closer young…

Astrophysics · Physics 2007-05-23 L. Townsley , E. Feigelson , T. Montmerle , P. Broos , Y. -H. Chu , G. Garmire , K. Getman