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This paper presents infrared spectra taken with the newly commissioned NIRSPEC spectrograph on the Keck II Telescope of the High Redshift Radio Galaxy MRC 2025-218 (z=2.63) These observations represent the deepest infrared spectra of a…

We report statistically significant detection of H I 21-cm emission from intermediate-redshift ($z\approx0.2$-0.6) galaxies. By leveraging multi-sightline galaxy survey data from the Cosmic Ultraviolet Baryon Survey (CUBS) and deep radio…

Near-infrared spectroscopy (rest-frame 3700-6800 Angstroms) of eight high redshift powerful radio galaxies (HzPRGs) at z = 2.2-2.6 is presented. Strong forbidden lines and H-alpha emission were detected in all sources; the data show…

Astrophysics · Physics 2009-10-30 A. S. Evans

We present an updated model of the cosmic ionizing background from the UV to the X-rays. Relative to our previous model (Faucher-Giguere et al. 2009), the new model provides a better match to a large number of up-to-date empirical…

Cosmology and Nongalactic Astrophysics · Physics 2020-02-05 C. -A. Faucher-Giguere

Lyman alpha (Lya) emission lines should be attenuated in a neutral intergalactic medium (IGM). Therefore the visibility of Lya emitters at high redshifts can serve as a valuable probe of reionization at about the 50% level. We present an…

(Abridged) Aims. To probe the spectral energy distribution (SED) of the ionizing background radiation at z ~ 2 and to specify the sources contributing to the intergalactic radiation field. Methods. The spectrum of a bright quasar…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 I. I. Agafonova , S. A. Levshakov , D. Reimers , H. -J. Hagen , D. Tytler

We use a Maximum-Likelihood analysis to constrain the value and evolution of the ionizing background for 2<z<4.5, taking account of possible systematic errors. (The paper has a more detailed abstract)

Astrophysics · Physics 2015-06-24 Andrew Cooke , Brian Espey , Bob Carswell

We present a high resolution (FWHM=2.7 km/s), high S/N echelle spectrum for the z = 2.26 QSO J2123-0050 and determine elemental abundances for the z = 2.06 sub-DLA in its line of sight. This high redshift sub-DLA has a complex kinematic…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Nikola Milutinovic , Sara L. Ellison , J. Xavier Prochaska , Jason Tumlinson

Cross-correlating the Planck High Frequency Instrument (HFI) maps against quasars from the Sloan Digital Sky Survey (SDSS) DR7, we estimate the intensity distribution of the Cosmic Infrared Background (CIB) over the redshift range 0 < z <…

Cosmology and Nongalactic Astrophysics · Physics 2014-12-05 Samuel J. Schmidt , Brice Ménard , Ryan Scranton , Christopher B. Morrison , Mubdi Rahman , Andrew M. Hopkins

We present the first calibrated CCD images of the faint supernova remnant G 114.3+0.3 in the emission lines of [OII], [OIII], Halpha+[NII] and [SII]. The deep low ionization CCD images reveal diffuse emission in the south and central areas…

Astrophysics · Physics 2009-11-07 F. Mavromatakis , P. Boumis , E. V. Paleologou

The Wisconsin H-Alpha Mapper (WHAM) Northern Sky Survey is revealing that many intermediate-velocity (|v_LSR| <= 100 km/s) neutral clouds and complexes have an associated ionized component. We present the first map of the H-Alpha emission…

Astrophysics · Physics 2009-11-06 L. M. Haffner , R. J. Reynolds , S. L. Tufte

Preliminary results are presented from a simple, single-antenna experiment designed to measure the all-sky radio spectrum between 100 and 200 MHz. The system used an internal comparison-switching scheme to reduce non-smooth instrumental…

Astrophysics · Physics 2009-11-13 Judd D. Bowman , Alan E. E. Rogers , Jacqueline N. Hewitt

We use the new results of the HEGRA detector on the TeV gamma-ray emission from MKN 501 to set upper limits on the energy density of the cosmic infrared background (CIRB). Contrary to previous interpretations of the gamma-ray spectrum of…

Astrophysics · Physics 2010-11-30 Todor Stanev , Alberto Franceschini

We present the integrated Halpha emission line profile for 157 HII regions in the central 3.4' x 3.4' of the galaxy M 83 (NGC 5236). Using the Fabry-Perot interferometer GHaFaS, on the 4.2 m William Herschel on La Palma, we show the…

The redshifted 21 cm brightness distribution from neutral hydrogen is a promising probe into the cosmic dark ages, cosmic dawn, and re-ionization. LOFAR's Low Band Antennas (LBA) may be used in the frequency range 45 MHz to 85 MHz (30>z>16)…

Instrumentation and Methods for Astrophysics · Physics 2015-06-16 H. K. Vedantham , L. V. E. Koopmans , A. G. de Bruyn , S. J. Wijnholds , B. Ciardi , M. A. Brentjens

The isotropic gamma-ray background (IGRB), measured by the Fermi Large Area Telescope, is the result of several classes of extragalactic astrophysical sources. Those sources include blazars, start-forming galaxies and radio galaxies. Also,…

High Energy Astrophysical Phenomena · Physics 2024-08-22 Ilias Cholis , Iason Krommydas

We report on the results of an IRAM-30m search for CO emission lines in three galaxies at intermediate redshifts. The idea was to investigate the molecular content of galaxies bright in the infrared at z=0.4-1.5, a redshift desert for…

Astrophysics · Physics 2009-11-13 A. -L. Melchior , F. Combes

We investigate the impact of quasars on the ionization of the surrounding intergalactic medium (IGM) with the radiative transfer code \texttt{CRASH4}, now accounting for X-rays and secondary electrons. After comparing with analytic…

Cosmology and Nongalactic Astrophysics · Physics 2019-01-08 Luca Graziani , B. Ciardi , M. Glatzle

In this second paper of the Hawaii SCUBA-2 Lensing Cluster Survey series, we cross-match SCUBA-2 maps with 3 and 6 GHz images from the Janksy-VLA Frontier Fields Legacy Survey for three cluster fields, MACS J0416.1--2403, MACS J0717.5+3745,…

Astrophysics of Galaxies · Physics 2017-05-10 Li-Yen Hsu , Vandana Desai , Eric Murphy , Lennox Cowie , Ian Heywood , Emmanuel Momjian , Amy Barger , Ian Smail

Direct measurements of the extragalactic background light (EBL) in the near-IR to mid-IR waveband are extremely difficult due to an overwhelming foreground from the zodiacal light that outshines the faint cosmological diffuse radiation…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Matthew Orr , Frank Krennrich , Eli Dwek
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