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We analyze all the available Atacama Large Millimeter / submillimeter Array archival data of the nearby Type-II Seyfert galaxy NGC 1068, including new 100 GHz data with the angular resolution of 0\farcs05, which was not included in previous…

Astrophysics of Galaxies · Physics 2023-08-02 Tomonari Michiyama , Yoshiyuki Inoue , Akihiro Doi

Aims: We have analyzed low frequency radio data of tidal disruption event (TDE) Swift J1644+57 to search for a counterpart. We consider how brief transient signals (on the order of seconds or minutes) originating from this location would…

We report on a search for Interstellar CH2D+. Four transitions occur in easily accessible portions of the spectrum; we report on emission at the frequencies of these transitions toward high column density star-forming regions. While the…

Astrophysics · Physics 2019-02-12 Alwyn Wootten , Barry E. Turner

We present first results of a new heterodyne spectrometer dedicated to high-resolution spectroscopy of molecules of astrophysical importance. The spectrometer, based on a roomtemperature heterodyne receiver, is sensitive to frequencies…

Instrumentation and Methods for Astrophysics · Physics 2018-09-12 Nadine Wehres , Bettina Heyne , Frank Lewen , Marius Hermanns , Bernhard Schmidt , Christian Endres , Urs U. Graf , Daniel R. Higgins , Stephan Schlemmer

We present the first southern-hemisphere all-sky imager and radio-transient monitoring system implemented on two prototype stations of the low-frequency component of the Square Kilometre Array. Since its deployment the system has been used…

The cosmic radio-frequency spectrum is expected to show a strong absorption signal corresponding to the 21-centimetre-wavelength transition of atomic hydrogen around redshift 20, which arises from Lyman-alpha radiation from some of the…

Cosmology and Nongalactic Astrophysics · Physics 2018-03-20 Rennan Barkana

We report on the first wide-field, very long baseline interferometry (VLBI) survey at 90 cm. The survey area consists of two overlapping 28 deg^2 fields centred on the quasar J0226+3421 and the gravitational lens B0218+357. A total of 618…

Astrophysics · Physics 2009-11-13 Emil Lenc , Mike A. Garrett , Olaf Wucknitz , James M. Anderson , Steven J. Tingay

We present observations of massive star-forming regions selected from the IRAS Point Source Catalog. The observations were made with the Very Large Array and the Large Millimeter Telescope to search for Class I methanol masers. We made…

We present deep 350- and 1200-micron imaging of the region around 4C41.17 -- one of the most distant (z = 3.792) and luminous known radio galaxies -- obtained with the Submillimeter High Angular Resolution Camera (SHARC-II) and the Max…

Astrophysics · Physics 2009-11-13 T. R. Greve , D. Stern , R. J. Ivison , C. De Breuck , A. Kovács , F. Bertoldi

We report high sensitivity sub-arcsecond angular resolution observations of the massive star forming region DR21(OH) at 3.6, 1.3, and 0.7 cm obtained with the Very Large Array. In addition, we conducted observations of CH3OH 44 GHz masers.…

Astrophysics of Galaxies · Physics 2011-02-11 Esteban D. Araya , Stan Kurtz , Peter Hofner , Hendrik Linz

High-redshift protoclusters consisting of dusty starbursts are thought to play an important role in galaxy evolution. Their dusty nature makes them bright in the FIR/submm but difficult to find in optical/NIR surveys. Radio observations are…

We present an International LOFAR Telescope sub-arcsecond resolution image of the nearby galaxy M 51 with a beam size of 0.436" x 0.366" and rms of 46 $\mu$Jy. We compare this image with an European VLBI Network study of M 51, and discuss…

High Energy Astrophysical Phenomena · Physics 2023-07-06 Deepika Venkattu , Peter Lundqvist , Miguel Pérez-Torres , Leah Morabito , Javier Moldón , John Conway , Poonam Chandra , Cyril Tasse

In this study we present 18 to 24 GHz and high angular resolution radio wavelength Australia Telescope Compact Array follow up observations towards a sample of 39 HC HII region candidates. These objects, taken from a sample hosting 6.7 GHz…

Astrophysics of Galaxies · Physics 2024-08-15 A. L. Patel , J. S. Urquhart , A. Y. Yang , T. Moore , M. A. Thompson , K. M. Menten , T. Csengeri

Up to date, only 6 imines have been detected in the interstellar medium. The 3-carbon imine, 2-propanimine ((CH$_3$)$_2$C=NH), is predicted to be the structural isomer with the lowest energy in the C$_3$H$_7$N group, and appears to be a…

We perform deep 1.8 cm radio continuum imaging towards thirteen protostellar regions selected from the Spitzer c2d small clouds and cores programme at high resolution (25") in order to detect and quantify the cm-wave emission from deeply…

We present new results of a study of the sub-millimetre continuum emission from a sample of 9 radio galaxies and 4 radio-quiet quasars at redshifts $z = 0.75 - 4.26$. The observations were made at 800$\mu m$, using the single-element…

Astrophysics · Physics 2015-06-24 David Hughes , J. S. Dunlop , Steve Rawlings

On 2014 April 23, the Swift satellite detected a gamma-ray superflare from the nearby star system DG CVn. This system comprises a M-dwarf binary with extreme properties: it is very young and at least one of the components is a very rapid…

High Energy Astrophysical Phenomena · Physics 2015-06-23 R. P. Fender , G. E. Anderson , R. Osten , T. Staley , C. Rumsey , K. Grainge , R. D. E. Saunders