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We report two epochs of Chandra-ACIS X-ray imaging spectroscopy of the nearby bright Type IIn supernova SN 2010jl, taken around 2 months and then a year after the explosion. The majority of the X-ray emission in both the spectra is…

High Energy Astrophysical Phenomena · Physics 2015-06-04 Poonam Chandra , Roger A. Chevalier , Christopher M. Irwin , Nikolai Chugai , Claes Fransson , Alicia M. Soderberg

We analyze the \ovi\ content and kinematics for 126 {\hi}-selected absorbers at $0.14 \lesssim z \lesssim 0.73$ for which the metallicities of their cool photoionized phase have been determined. We separate the absorbers into 100 strong…

Astrophysics of Galaxies · Physics 2024-09-10 Sameer , Nicolas Lehner , J. Christopher Howk , Andrew J. Fox , John M. O'Meara , Benjamin D. Oppenheimer

We present the first results from our NASA Keck Observatory Database of Ionized Absorbers toward Quasars (KODIAQ) survey which aims to characterize the properties of the highly ionized gas of high redshift galaxies and their circumgalactic…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Nicolas Lehner , John M. O'Meara , Andrew J. Fox , J. Christopher Howk , J. Xavier Prochaska , Vincent Burns , Ashley A. Armstrong

Using a hydrodynamic simulation of a LCDM universe, we investigate the "X-ray forest" absorption imprinted on the spectra of background quasars by the intervening intergalactic medium (IGM). In agreement with previous studies, we find that…

Astrophysics · Physics 2009-11-07 Xuelei Chen , David H. Weinberg , Neal Katz , Romeel Dave'

We have obtained spatially resolved spectra of the z=3.911 triply imaged QSO APM08279+5255 using the Space Telescope Imaging Spectrograph (STIS) on board the Hubble Space Telescope (HST). We study the line of sight equivalent width (EW)…

We present the results of reanalysis of low z Mg II absorption line sample compiled by SS92. The conditions on cloud parameters to produce N(Fe II)>N(Mg II) are obtained using photoionization models and curve of growth. Properties of Mg II…

Astrophysics · Physics 2009-10-28 R. Srianand

We report on our first results from a mid-infrared spectroscopic study of ISM features in a sample of deeply obscured ULIRG nuclei using the InfraRed Spectrograph (IRS) on the Spitzer Space Telescope. The spectra are extremely rich and…

We present a detailed analysis of absorption systems along the line of sight towards QSO PKS 0237-233 using a high resolution spectrum of signal-to-noise ratio (SNR) ~ 60-80 obtained with the Ultraviolet and Visual Echelle Spectrograph…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 H. Fathivavsari , P. Petitjean , C. Ledoux , P. Noterdaeme , R. Srianand , H. Rahmani , A. Ajabshirizadeh

We present an ultraviolet quasar absorption line analysis of metal lines associated with three strong intervening H I absorbers (with $N$(H I) $>$ 10$^{16.5}$ cm$^{-2}$) detected in the outskirts of Sunyaev-Zel'dovich (SZ) effect-selected…

Astrophysics of Galaxies · Physics 2019-08-07 Jayadev Pradeep , Anand Narayanan , Sowgat Muzahid , Daisuke Nagai , Jane C. Charlton , Raghunathan Srianand

Herschel/PACS observations of 29 local (Ultra-)Luminous Infrared Galaxies, including both starburst and AGN-dominated sources as diagnosed in the mid-infrared/optical, show that the equivalent width of the absorbing OH 65 um Pi_{3/2}…

Cool gas should be present in galaxy clusters due to stripping of galactic gas, infall onto the cluster, and from cooling flows. We searched for this gas through resonance absorption line observations from low-ionization metal line gas…

Astrophysics · Physics 2007-05-23 Eric D. Miller , Joel N. Bregman , Patricia M. Knezek

We report the detection of Mg II absorption in two Lyman alpha forest clouds along the line of sight to PKS 0454+039. These clouds, at redshifts z=0.6248 and z=0.9315, respectively, also have strong Fe II absorption. We present results on…

Astrophysics · Physics 2008-02-03 Christopher W. Churchill , Vincent Le Brun

Broad Absorption Line Regions - BALR are composed of a number of successive independent absorbing density layers. Using the GR model, we analyze the UV Si IV ({\lambda}{\lambda}1393.755 - 1402.770), O IV ({\lambda}1401.156) and C IV…

Astrophysics of Galaxies · Physics 2014-05-14 Ch. Katsavrias , E. Danezis , A. Antoniou

We present XMM-Newton observations of four BL Lac objects (1H1219+301, H1426+428, Markarian 501 and PKS 0548-322), which have been found with past X-ray missions to contain evidence of broad soft X-ray absorption features. Observations with…

Astrophysics · Physics 2009-11-10 A. J. Blustin , M. J. Page , G. Branduardi-Raymont

We present 21-cm absorption measurements towards 12 radio continuum sources with previously identified thermally-unstable warm neutral medium (WNM). These observations were obtained with the Expanded Very Large Array (EVLA) and were…

Astrophysics of Galaxies · Physics 2015-05-20 Ayesha Begum , Snezana Stanimirovic , W. M. Goss , Carl Heiles , Anthony S. Pavkovich , Patrick Hennebelle

We performed a blind search for narrow absorption features at energies greater than 6.4 keV in a sample of 42 radio-quiet AGNs observed with XMM-Newton. We detect 36 narrow absorption lines on a total of 101 XMM-Newton EPIC pn observations.…

High Energy Astrophysical Phenomena · Physics 2015-05-19 F. Tombesi , M. Cappi , J. N. Reeves , G. G. C. Palumbo , T. Yaqoob , V. Braito , M. Dadina

The extraordinarily bright quasar PHL 1811 at a redshift z = 0.192 provides an attractive opportunity to use ultraviolet absorption-line spectroscopy to study the properties of gas systems in the local universe. An R = 20,000 far-UV…

We report the discovery of a further line of sight allowing detection of HeII Ly alpha absorption by the intergalactic medium. A HST/STIS survey of 32 bright z ~ 3 quasars selected from the Hamburg Quasar Surveys yielded one detection…

Astrophysics · Physics 2016-08-30 D. Reimers , C. Fechner , H. -J. Hagen , P. Jakobsen , D. Tytler , D. Kirkman

We present for the first time a high-resolution X-ray spectrum of a Seyfert galaxy. The Chandra-LETGS spectrum of NGC 5548 shows strong, narrow absorption lines from highly ionised species (the H-like and He-like ions of C, N, O, Ne, Na,…

Astrophysics · Physics 2007-05-23 J. S. Kaastra , R. Mewe , D. A. Liedahl , S. Komossa , A. C. Brinkman

We have studied a sample of 415 associated (z_ab z_em; relative velocity with respect to QSO <3000km/s) Mg II absorption systems with 1.0<=z_ab<=1.86, in the spectra of SDSS DR3 QSOs, to determine the dust content and ionization state in…