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Ionized carbon is the main gas-phase reservoir of carbon in the neutral diffuse interstellar medium and its 158 micron fine structure transition [CII] is the most important cooling line of the diffuse interstellar medium (ISM). We combine…

This study presents results on detecting neutral atomic hydrogen (HI) 21cm absorption in the spectrum of PKS1413+135 at redshift $z=0.24670041$. The observation was conducted by FAST, with a spectral resolution of 10 Hz, using 10 minutes of…

Cosmology and Nongalactic Astrophysics · Physics 2025-04-08 Jiangang Kang , Chang-Zhi Lu , TongJie Zhang , Ming Zhu

QSO absorption spectra provide an extremely useful probe of possible cosmological variation in various physical constants. Comparison of H I 21cm absorption with corresponding molecular (rotational) absorption spectra allows us to constrain…

Astrophysics · Physics 2009-08-18 M. T. Murphy , J. K. Webb , V. V. Flambaum , M. J. Drinkwater , F. Combes , T. Wiklind

[Slightly Abridged] We present a detailed statistical analysis of the column densities, N, and Doppler parameters, b, of MgII absorbing clouds at redshifts 0.4<z<1.2. We use the HIRES/Keck data and Voigt profile (VP) fitting results…

Astrophysics · Physics 2009-11-07 Chris Churchill , Steven Vogt , Jane Charlton

We assemble 3524 quasars from Sloan Digital Sky Survey (SDSS) with repeated observations to search for variations of narrow C IV1548,1551 and Mg II2796,2803 absorption doublets in spectral regions shortward of 7000 Ang at the observed…

Astrophysics of Galaxies · Physics 2015-09-22 Zhi-Fu Chen , Qiu-Sheng Gu , Yan-Mei Chen , Yue Cao

We present new Hubble Space Telescope (HST)/Cosmic Origins Spectrograph observations of the Narrow-Line Seyfert 1 galaxy NGC 4051. These data were obtained as part of a coordinated observing program including X-ray observations with the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 S. B. Kraemer , D. M. Crenshaw , J. P. Dunn , T. J. Turner , A. P. Lobban , L. Miller , J. N. Reeves , T. C. Fischer , V. Braito

We found a broad absorption line (BAL) outflow in the VLT/UVES spectrum of the quasar SDSS J235702.54-004824.0, in which we identified four subcomponents. We measured the column densities of the ions in one of the subcomponents ($v$ = -1600…

Astrophysics of Galaxies · Physics 2022-09-22 Doyee Byun , Nahum Arav , Patrick B. Hall

Spectra of the z_em = 3.268 quasar PKS 2126-158 have been obtained in the range lambda lambda 4300-6620 A with a resolution R = 27000 and an average signal-to-noise ratio s/n = 25 per resolution element. The list of the identified…

Astrophysics · Physics 2011-05-23 V. D'Odorico , S. Cristiani , S. D'Odorico , A. Fontana , E. Giallongo

Recent JWST observations of massive galaxies at z > 2 have detected blueshifted absorption in Na I D and other resonant absorption lines, indicative of strong gas outflows in the neutral phase. However, the measured mass outflow rates are…

We have conducted a systematic survey for intervening OVI absorbers in available echelle spectra of 16 QSOs at z_QSO = 0.17-0.57. These spectra were obtained using HST/STIS with the E140M grating. Our search uncovered a total of 27…

Astrophysics · Physics 2009-11-13 Christopher Thom , Hsiao-Wen Chen

We have observed SN1998S which exploded in NGC3877, with the UES at the WHT and with the E230M echelle of STIS aboard HST. Both data sets were obtained at two seperate epochs. From our own Galaxy we detect interstellar absorption lines of…

Astrophysics · Physics 2009-10-31 David V. Bowen , Katherine C. Roth , David M. Meyer , J. Chris Blades

With our robotic 1.2 m TIGRE telescope, we were able to obtain eight optical spectra with intermediate resolution (R = 20,000) of the Nova V659 Sct during different phases of its outburst. We present a list of the lines found in the Nova…

We present an analysis of moderately high resolution optical spectra obtained for the sight line to CD-23 13777, an O9 supergiant that probes high velocity interstellar gas associated with the supernova remnant W28. Absorption components at…

Astrophysics of Galaxies · Physics 2023-05-30 Adam M. Ritchey

% aims To compare information gained from radio and optical absorption line profiles from the diffuse interstellar medium along the same sightline % methods We compare new and existing 21cm HI and 3.4mm HCO+ profiles with profiles of the…

Astrophysics of Galaxies · Physics 2021-05-03 Harvey Liszt

We have obtained observations of the ultraviolet spectrum of AM CVn, an ultra-short-period helium cataclysmic variable, using the Space Telescope Imaging Spectrograph (STIS) aboard the Hubble Space Telescope (HST). We obtained data in…

Astrophysics · Physics 2019-08-14 Richard A. Wade , Michael Eracleous , Helene M. L. G. Flohic

We report on the abundance of interstellar neutral oxygen (OI) for 26 sightlines, using data from the Far Ultraviolet Spectroscopic Explorer (FUSE), the International Spectroscopic Explorer (IUE), and the Hubble Space Telescope (HST). OI…

Astrophysics · Physics 2009-11-10 Adam G. Jensen , Brian L. Rachford , Theodore P. Snow

We report a deep Giant Metrewave Radio Telescope (GMRT) search for Galactic H{\sc i} 21cm absorption towards the quasar B0438$-$436, yielding the detection of wide, weak H{\sc i} 21cm absorption, with a velocity-integrated H{\sc i} 21cm…

A table is presented that summarizes published absorption line measurements for the high- and intermediate velocity clouds (HVCs and IVCs). New values are derived for N(HI) in the direction of observed probes, in order to arrive at reliable…

Astrophysics · Physics 2009-11-06 B. P. Wakker

Over the course of its motion through the Galaxy, our solar system has encountered many interstellar environments of varying characteristics. Interstellar medium (ISM) density variations spanning seven orders of magnitude are commonly seen…

Solar and Stellar Astrophysics · Physics 2015-06-16 Katherine Wyman , Seth Redfield

Observations of the yellow hypergiant Rho Cas obtained in 2007-2011 in a wide wavelength region with spectral resolution about 60000 have enabled studies of features of its optical spectrum in detail and brought to light previously unknown…

Solar and Stellar Astrophysics · Physics 2015-06-18 V. G. Klochkova , V. E. Panchuk , N. S. Tavolganskaya , I. A. Usenko