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Related papers: Molecular gas at intermediate redshifts

200 papers

We report new observations of the 110-111 (6 cm) and 211-212 (2 cm) transitions of ortho-formaldehyde (o-H2CO) in absorption at z=0.68466 toward the gravitational lens system B0218+357. Radiative transfer modeling indicates that both…

Astrophysics of Galaxies · Physics 2010-01-05 Benjamin Zeiger , Jeremy Darling

STIS Echelle observations at a resolution of 10 km/s and UVES/VLT spectroscopy at a resolution of 7 km/s of the luminous QSO HE 0515-4414 (z_em = 1.73, B = 15.0) reveal four intervening O VI absorption systems in the redshift range 1.2 <…

Astrophysics · Physics 2009-11-06 Dieter Reimers , Robert Baade , Hans-Juergen Hagen , Sebastian Lopez

We present results from a spectroscopically blind search for associated and intervening HI 21-cm and OH 18-cm absorption lines towards 88 AGNs at $2\le z\le5$ using the upgraded Giant Metrewave Radio Telescope (uGMRT). The sample of AGNs…

We present results from 12 km/s resolution echelle spectroscopy of the bright $z=4.694$ QSO BR1202-0725. A preliminary analysis shows that high metallicity narrow line absorption clouds are present up to the redshift of the quasar. A damped…

Astrophysics · Physics 2007-05-23 E. J. Wampler , G. M. Williger , J. A. Baldwin , R. F. Carswell , C. Hazard , R. G. McMahon

Absorption-selected galaxies offer an effective way to study low-mass galaxies at high redshift. However, the physical properties of the underlying galaxy population remains uncertain. In particular, the multiphase circum-galactic medium is…

Astrophysics of Galaxies · Physics 2021-06-30 Anne Klitsch , Celine Peroux , Martin A. Zwaan , Annalisa De Cia , Cedric Ledoux , Sebastian Lopez

We study the structure and kinematics of the OH-streamer and the +80 km/s cloud and their interactions with the circumnuclear disk (CND) and with other molecular clouds in the vicinity of the Galactic centre (GC), and we map OH absorption…

Astrophysics of Galaxies · Physics 2015-11-04 Roland Karlsson , Aage Sandqvist , Kambiz Fathi , Sergio Martín

We have carried out a blind search in the general direction of the Galactic Anticenter for absorption of the Cosmic Microwave Background (CMB) radiation near 4.83 GHz by molecular clouds containing gaseous ortho-formaldehyde (H_2CO). The…

Astrophysics · Physics 2008-11-26 Monica Ivette Rodriguez , Ronald J. Allen , Laurent Loinard , Tommy Wiklind

The hydroxyl radical (OH) is present in the diffuse molecular and partially atomic phases of the interstellar medium (ISM), but its abundance relative to hydrogen is not clear. We aim to evaluate the abundance of OH with respect to…

We present the results of a z>2.9 survey for HI 21-cm and molecular absorption in the hosts of radio quasars using the GMRT and the Tidbinbilla 70-m telescope. Previously published searches, which are overwhelmingly at redshifts of z<1,…

Astrophysics · Physics 2015-05-13 S. J. Curran , M. T. Whiting , T. Wiklind , J. K. Webb , M. T. Murphy , C. R. Purcell

Some recent results are presented about high redshift molecular absorption lines, namely about chemical abundances of elements, and in particular of water and molecular oxygen. Excitation temperatures of several molecules are found lower…

Astrophysics · Physics 2007-05-23 F. Combes , T. Wiklind

We examine the relationship between galaxies and the intergalactic medium at z < 1 using a group of three closely spaced background QSOs with z_em ~1 observed with the Hubble Space Telescope. Using a new grouping algorithm, we identify…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Neil H. M. Crighton , Simon L. Morris , Jill Bechtold , Robert A. Crain , Buell T. Jannuzi , Allen Shone , Tom Theuns

High-resolution UV spectroscopy of low-z QSOs with the Space Telescope Imaging Spectrograph and the Far Ultraviolet Spectroscopic Explorer has indicated that O VI absorption-line systems provide a valuable probe of the low-z intergalactic…

Astrophysics · Physics 2007-05-23 Todd M. Tripp

We have obtained OH spectra of four transitions in the $^2\Pi_{3/2}$ ground state, at 1612, 1665, 1667, and 1720 MHz, toward 51 sightlines that were observed in the Herschel project Galactic Observations of Terahertz C+. The observations…

Measuring rest-frame ultraviolet rotational transitions from the Lyman and Werner bands in absorption against a bright background continuum is one of the few ways to directly measure molecular hydrogen (H2). Here we report the detection of…

We have observed the four hyperfine components of the 18 cm OH transition toward the translucent cloud eastward of Heiles Cloud 2 (HCL2E), the cold dark cloud L134N, and the photodissociation region of the $\rho$-Ophiuchi molecular cloud…

Astrophysics of Galaxies · Physics 2016-02-18 Yuji Ebisawa , Hiroshi Inokuma , Nami Sakai , Karl M. Menten , Hiroyuki Maezawa , Satoshi Yamamoto

ORFEUS far UV echelle spectra have been used to investigate HI, H_2 and CO absorption lines along the line of sight towards LH 10:3120 in the LMC, extending the study presented by de Boer et al. (1998). While H_2 absorption is clearly…

Astrophysics · Physics 2007-05-23 P. Richter , K. S. de Boer , D. J. Bomans , Y. -N. Chin , A. Heithausen , J. Koornneef

The four known molecular absorption line systems at redshifts z$=$0.25--0.89 are discussed. Two of the systems originate in the galaxy hosting the `background' AGN, while in two cases the absorption occurs in truely intervening galaxies.…

Astrophysics · Physics 2007-05-23 Tommy Wiklind , Francoise Combes

Using the Effelsberg 100-m telescope, absorption in the (J,K) = (1,1), (2,2) and (3,3) inversion lines of ammonia (NH_3) was detected at a redshift of z = 0.6847 toward the gravitational lens system B0218+357. The lambda ~ 2cm absorption…

Astrophysics · Physics 2009-11-11 C. Henkel , N. Jethava , A. Kraus , K. M. Menten , C. L. Carilli , M. Grasshoff , D. Lubowich , M. J. Reid , .

High signal-to-noise spectra toward background quasars are crucial for uncovering weak absorption in the circumgalactic medium (CGM) of intervening galaxies, such as the diagnostic lines of N V that provide insight to the ionization process…

We have conducted OH 18 cm survey toward 141 molecular clouds in various environments, including 33 optical dark clouds, 98 Planck Galactic cold clumps (PGCCs) and 10 Spitzer dark clouds with the Arecibo telescope. The deviations from local…

Astrophysics of Galaxies · Physics 2020-12-23 Ningyu Tang , Di Li , Nannan Yue , Pei Zuo , Tie Liu , Gan Luo , Longfei Chen , Sheng-Li Qin , Yuefang Wu , Carl Heiles