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Related papers: Chandra ACIS-I particle background: an analytical …

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We present a small sample of Chandra X-ray sources selected from the fields of ACIS observations which probe fluxes around the break in the hard band source counts. The targets of these fields include 9 nearby galaxy clusters, 1 distant…

Astrophysics · Physics 2009-09-17 P. Gandhi , C. S. Crawford , A. C. Fabian , R. M. Johnstone

We describe the results of a 2003 Chandra ACIS-I observation of SN1978K. The spectrum shows little flux below 0.6 keV, in contrast to the 2002 ACIS-S observation that showed flux to 0.4 keV. Fitting the ACIS-I spectrum alone leads to two…

Astrophysics · Physics 2008-11-26 E. Lenz , E. M. Schlegel

The Chandra Multiwavength Plane (ChaMPlane) Survey of the galactic plane incorporates serendipitous sources from selected Chandra pointings in or near the galactic plane (b < 12deg; >20 ksec; lack of bright diffuse or point sources) to…

NGC 1333, a highly active star formation region within the Perseus molecular cloud complex, has been observed with the ACIS-I detector on board the Chandra X-ray Observatory. In our image with a sensitivity limit of ~ 1e28 erg/s, we detect…

We present a Chandra ACIS-S observation of the nuclear region of the nearby spiral galaxy M51 (NGC 5194), which has a low-luminosity Seyfert 2 nucleus. The X-ray image shows the nucleus, southern extranuclear cloud, and northern loop, the…

Astrophysics · Physics 2009-11-06 Yuichi Terashima , Andrew S. Wilson

We use analytic computations to predict the power spectrum as well as the bispectrum of Cosmic Infrared Background (CIB) anisotropies. Our approach is based on the halo model and takes into account the mean luminosity-mass relation. The…

Cosmology and Nongalactic Astrophysics · Physics 2020-01-08 Robert Reischke , Vincent Desjacques , Saleem Zaroubi

We searched in the public archive of the Chandra X-ray Observatory as of March 2016 and assembled a sample of 719 galaxies within 50 Mpc with ACIS observations available. By cross-correlation with the optical or near-infrared nuclei of…

Astrophysics of Galaxies · Physics 2017-02-08 Rui She , Luis C. Ho , Hua Feng

(Abridged) We present an analysis of the 700 ks Chandra ACIS-S observation of the field around the Spiderweb Galaxy at z=2.156, focusing on the nuclear activity in the associated large-scale environment. We identify unresolved X-ray sources…

The origin of the X-ray background, in particular at hard (2-10 keV) energies, has been a debated issue for more than 30 years. The Chandra deep fields provide the deepest look at the X-ray sky and are the best dataset to study the X-ray…

Astrophysics · Physics 2009-11-07 S. Campana , A. Moretti , D. Lazzati , G. Tagliaferri

An alternative scheme is described to estimate the layer 1 LAXPC 20 background for faint sources where the source contribution to the 50-80 keV count rate is less than 0.25 counts/sec (15 milli-crabs or $6 \times 10^{-11}$ ergs/s/cm$^2$).…

Instrumentation and Methods for Astrophysics · Physics 2021-07-07 Ranjeev Misra , Jayashree Roy , J. S. Yadav

An observation of the gravitationally lensed system 2016+112 with the Chandra X-ray Observatory has resolved a mystery regarding the proposed presence of a dark matter object in the lens plane of this system. The Chandra ACIS observation…

Astrophysics · Physics 2009-11-06 G. Chartas , M. Bautz , G. Garmire , C. Jones , D. P. Schneider

We present a detailed spectral analysis of the data obtained from NGC 3783 during the period 2000-2001 using Chandra. This analysis leads us to the following results. 1) NGC 3783 fluctuated in luminosity by a factor ~1.5 during individual…

In high-resolution X-ray observations of the hot plasma in clusters of galaxies significant structures caused by AGN feedback, mergers, and turbulence can be detected. Many clusters have been observed by Chandra in great depth and at high…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-13 F. Hofmann , J. S. Sanders , K. Nandra , N. Clerc , M. Gaspari

The search for diffuse non-thermal inverse Compton (IC) emission from galaxy clusters at hard X-ray energies has been undertaken with many instruments, with most detections being either of low significance or controversial. Background and…

The Advanced CCD Imaging Spectrometer is an instrument on the Chandra X-ray Observatory. CCDs are vulnerable to radiation damage, particularly by soft protons in the radiation belts and solar storms. The Chandra team has implemented…

Instrumentation and Methods for Astrophysics · Physics 2015-06-05 C. E. Grant , P. G. Ford , M. W. Bautz , S. L. O'Dell

The CHandra Extended Emission Line Region Survey (CHEERS) is an X-ray study of nearby active galactic nuclei (AGN) designed to take full advantage of Chandra's unique angular resolution by spatially resolving feedback signatures and…

This paper describes the {\it Chandra} observation of the diffuse emission in the face-on spiral NGC 6946. Overlaid on optical and H${\alpha}$ images, the diffuse emission follows the spiral structure of the galaxy. An overlay on a 6 cm…

Astrophysics · Physics 2009-11-10 E. M. Schlegel , S. S. Holt , R. Petre

The Chandra COSMOS Survey (C-COSMOS) is a large, 1.8 Ms, Chandra program, that covers the central contiguous ~0.92 deg^2 of the COSMOS field. C-COSMOS is the result of a complex tiling, with every position being observed in up to six…

This paper is the third in a series in which we present deep Chandra ACIS-S imaging spectroscopy of the Seyfert 1 galaxy NGC 4151, devoted to study its complex circum-nuclear X-ray emission. Emission features in the soft X-ray spectrum of…

We have searched for unresolved X-ray sources in the vicinity of two rich clusters of galaxies: Abell 1995 (A1995) and MS 0451.6-0305 (MS0451), using the Chandra X-ray observatory. We detected significantly more unresolved sources around…

Astrophysics · Physics 2009-11-07 S. M. Molnar , J. P. Hughes , M. Donahue , M. Joy