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A search for potential point sources of very high energy gamma rays has been carried out on the data taken simultaneously by the HEGRA AIROBICC and Scintillator arrays from August 1994 to March 2000. The list of sought sources includes…

Astrophysics · Physics 2007-05-23 HEGRA Collaboration , F. A. Aharonian

We used the NRAO Very Large Array to search for 3.6 cm continuum emission from embedded protostars in a sample of 8 nearby ``starless'' cores that show spectroscopic evidence for infalling motions in molecular emission lines. We detect a…

Astrophysics · Physics 2009-11-07 D. W. A. Harvey , D. J. Wilner , J. Di Francesco , C. -W. Lee , P. C. Myers , J. P. Williams

Breakthrough Listen (BL) is a ten-year initiative to search for signatures of technologically capable life beyond Earth via radio and optical observations of the local Universe. A core part of the BL program is a comprehensive survey of…

Centaurus A (Cen~A) is the nearest active radio galaxy, which has kiloparsec (kpc) scale jets and {giant lobes detected by various instruments in radio and X-ray frequency ranges}. The $Fermi$--Large Area Telescope and High Energy…

High Energy Astrophysical Phenomena · Physics 2019-08-07 Kazuhisa Tanada , Jun Kataoka , Yoshiyuki Inoue

We consider the capabilities for detecting low order CO emission lines from high-z galaxies using the next generation of radio telescopes operating at 22 and 43 GHz. We employ models for the evolution of dusty star forming galaxies based on…

Astrophysics · Physics 2009-11-07 C. L. Carilli , A. W. Blain

We summarize results of a search for X-ray-emitting binary stars in the massive globular cluster Omega Centauri (NGC 5139) using Chandra and HST. ACIS-I imaging reveals 180 X-ray sources, of which we estimate that 45-70 are associated with…

Astrophysics of Galaxies · Physics 2015-05-20 Daryl Haggard , Adrienne M. Cool , Tersi Arias , Michelle B. Brochmann , Jay Anderson , Melvyn B. Davies

When scientific experiments require transmission of powerful laser or radio beams through the atmosphere the Federal Aviation Administration (FAA) requires that precautions be taken to avoid inadvertent illumination of aircraft. Here we…

Instrumentation and Methods for Astrophysics · Physics 2015-05-14 W. A. Coles , T. W. Murphy , J. F. Melser , J. K. Tu , G. A. White , K. H. Kassabian , K. Bales , B. B. Baumgartner

We present spectra of the diffuse FUV (900 -- 1200 \AA) emission from a region near the Orion Nebula: the first high resolution spectra of the diffuse background radiation. These observations were made using serendipitous FUSE observations…

Astrophysics · Physics 2009-11-10 Jayant Murthy , David J. Sahnow , R. C. Henry

We present results from a 47 ks observation of the Andromeda galaxy, M31, using the High-Resolution Camera of the Chandra X-Ray Observatory. We detect 142 point sources spanning three orders of magnitude in luminosity, from $L_X = 2\times…

Astrophysics · Physics 2009-11-07 Philip Kaaret

We report on an analysis of \fermi data from four year of observations of the nearby radio galaxy Centaurus A (Cen A). The increased photon statistics results in a detection of high-energy ($>\:100$ MeV) $\gamma$-rays up to 50 GeV from the…

High Energy Astrophysical Phenomena · Physics 2015-06-15 N. Sahakyan , R. Yang , F. A. Aharonian , F. M. Rieger

We have carried out high resolution observations with Atacama Large Millimeter/Submillimeter Array (ALMA) of continuum emission from Orion KL region. We identify 11 compact sources at ALMA band 6 (245 GHz) and band 7 (339 GHz), including…

Solar and Stellar Astrophysics · Physics 2015-06-23 Tomoya Hirota , Mi Kyoung Kim , Yasutaka Kurono , Mareki Honma

(Abridged) We report results from a comprehensive study of the nearby M dwarf Proxima Centauri with the XMM-Newton satellite. We find strongly variable coronal X-ray emission, with flares ranging over a factor of 100 in peak flux. The…

Astrophysics · Physics 2009-11-10 M. Guedel , M. Audard , F. Reale , S. L. Skinner , J. L. Linsky

The pioneering experiments of linear spectroscopy were performed using flames in the 1800s, but nonlinear optical measurements had to wait until lasers became available in the twentieth century. Because the nonlinear cross section of…

Quantum Physics · Physics 2016-07-13 Andreas Maser , Benjamin Gmeiner , Tobias Utikal , Stephan Götzinger , Vahid Sandoghdar

A laser frequency combs is a broad spectrum composed of equidistant narrow lines. Initially invented for frequency metrology, such combs enable new approaches to spectroscopy over broad spectral bandwidths, of particular relevance to…

Optics · Physics 2019-03-01 Nathalie Picqué , Theodor W. Hänsch

We report a 0.2" resolution, 15 GHz survey of a sample of 48 low-luminosity active galactic nuclei with the Very Large Array. Compact radio emission has been detected in 57% (17 of 30) of LINERs and low-luminosity Seyferts, at least 15 of…

Astrophysics · Physics 2009-10-31 Neil M. Nagar , Heino Falcke , Andrew S. Wilson , Luis C. Ho

Using a turn-key Ti:sapphire femtosecond laser frequency comb, an off-the-shelf supercontinuum device, and Fabry-Perot mode filters, we report the generation of a 16 GHz frequency comb spanning a 90 nm band about a center wavelength of 566…

Planck data towards the active galaxy Centaurus A are analyzed in the 70, 100 and 143 GHz bands. We find a temperature asymmetry of the northern radio lobe with respect to the southern one that clearly extends at least up to 5 degrees from…

Over the last two decades, frequency combs have brought breakthroughs in length metrology with traceability to length standards. In particular, frequency-comb-based spectral interferometry is regarded as a promising technology for…

Optics · Physics 2025-01-20 Yoon-Soo Jang , Heulbi Ahn , Sunghoon Eom , Jungjae Park , Jonghan Jin

We present the target selection for the Breakthrough Listen search for extraterrestrial intelligence during the first year of observations at the Green Bank Telescope, Parkes Telescope and Automated Planet Finder. On the way to observing…

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