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Related papers: Radio source calibration for the VSA and other CMB…

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We develop an absolute flux density scale for cm-wavelength astronomy by combining accurate flux density ratios determined by the VLA between the planet Mars and a set of potential calibrators with the Rudy thermophysical emission model of…

Instrumentation and Methods for Astrophysics · Physics 2015-06-12 Rick A. Perley , Bryan J. Butler

The Planck mission detected thousands of extragalactic radio sources at frequencies from 28 to 857 GHz. Planck's calibration is absolute (in the sense that it is based on the satellite's annual motion around the Sun and the temperature of…

Cosmology and Nongalactic Astrophysics · Physics 2016-04-27 B. Partridge , M. López-Caniego , R. A. Perley , J. Stevens , B. J. Butler , G. Rocha , B. Walter , A. Zacchei

We present preliminary results from a VLBI survey at $\lambda=6 $cm of a sample of 35 sources with flux densities of 2 - 100 mJy. These sources were selected from the VLA FIRST survey at $\lambda = 20 $cm, in a 3 degree field around the…

Astrophysics · Physics 2009-10-31 S. T. Garrington , M. A. Garrett , A. Polatidis

The flux density scale of Perley and Butler (2013) is extended downwards to ~50 MHz by utilizing recent observations with the Karl G. Jansky Very Large Array (VLA) of 20 sources between 220 MHz and 48.1 GHz, and legacy VLA observations at…

Instrumentation and Methods for Astrophysics · Physics 2017-05-31 R. A. Perley , B. J. Butler

The Very Small Array (VSA) has been used to survey the l = 27 to 46 deg, |b|<4 deg region of the Galactic plane at a resolution of 13 arcmin. The survey consists of 44 pointings of the VSA, each with a r.m.s. sensitivity of ~90 mJy/beam.…

We describe the source subtraction strategy and observations for the extended Very Small Array, a CMB interferometer operating at 33 GHz. A total of 453 sources were monitored at 33 GHz using a dedicated source subtraction baseline. 131…

We present the observational results from the 43-GHz Very Long Baseline Array (VLBA) observations of 124 compact radio-loud active galactic nuclei (AGNs) that were conducted between 2014 November and 2016 May. The typical dimensions of the…

High Energy Astrophysical Phenomena · Physics 2020-07-07 X. -P. Cheng , T. An , S. Frey , X. -Y. Hong , X. He , K. I. Kellermann , M. L. Lister , B. -Q. Lao , X. -F. Li , P. Mohan , J. Yang , X. -C. Wu , Z. -L. Zhang , Y. -K. Zhang , W. Zhao

(Abridged) We present WMAP seven-year observations of bright sources which are often used as calibrators at microwave frequencies. Ten objects are studied in five frequency bands (23 - 94 GHz): the outer planets (Mars, Jupiter, Saturn,…

Small angular scale (high l) studies of cosmic microwave background anisotropies require accurate knowledge of the statistical properties of extragalactic sources at cm-mm wavelengths. We have used a 30 GHz dual-beam receiver (OCRA-p) on…

We are pursuing a project to build a database of phase calibration sources suitable for Giant Metrewave Radio Telescope (GMRT). Here we present the first release of 45 low frequency calibration sources at 235 MHz and 610 MHz. These…

Instrumentation and Methods for Astrophysics · Physics 2016-10-19 Dharam V. Lal , Shilpa S. Dubal , Sachin S. Sherkar

We have obtained 8.4 GHz VLBA observations of a 31-GHz complete sample of ~100 sources between 10 and 100 mJy. The main goals of these observations are: to determine the angular size, radio spectra and identification for a weak sample of…

Astrophysics · Physics 2008-06-19 W. A. Majid , E. B. Fomalont , D. S. Bagri

We present new millimetre 43 GHz observations of a sample of radio-bright Planetary Nebulae. Such observations were carried out to have a good determination of the high-frequency radio spectra of the sample in order to evaluate, together…

Astrophysics · Physics 2009-11-13 G. Umana , P. Leto , C. Trigilio , C. S. Buemi , P. Manzitto , S. Toscano , S. Dolei , L. Cerrigone

The planets Uranus and Neptune with small apparent diameters are primary calibration standards. We investigate their variability at ~90 GHz using archived data taken at the IRAM 30m telescope during the 20 years period 1985 to 2005. We…

Astrophysics · Physics 2009-11-13 C. Kramer , R. Moreno , A. Greve

A sample of 123 radio sources that exhibit significant variations at 1.4 GHz on a seven year base-line has been created using FIRST VLA B-array data from 1995 and 2002 on a strip at dec=0 near the south Galactic cap. This sample spans the…

Astrophysics · Physics 2009-11-10 W. H. de Vries , R. H. Becker , R. L. White , D. J. Helfand

We report further results from our imaging survey at 15GHz (lambda=2 cm) with the Very Long Baseline Array. This paper presents single epoch images for 39 sources, bringing the total number of objects in the sample to 171. Our sample is…

Astrophysics · Physics 2009-11-07 J. A. Zensus , E. Ros , K. I. Kellermann , M. H. Cohen , R. C. Vermeulen , M. Kadler

We present the in-orbit calibration of the Visible Telescope (VT), one of the key instruments aboard the Space Variable Objects Monitor (SVOM) mission for gamma-ray burst (GRB) studies. Using Gaia Data Release 3 (DR3) as a reference, the VT…

High Energy Astrophysical Phenomena · Physics 2026-04-28 Zhu-Heng Yao , Yu-Lei Qiu , Jin-Song Deng , Li-Ping Xin , Chao Wu , Hua-Li Li , Jing Wang , Yi-Nuo Ma , Hong-Bo Cai , Xu-Hui Han , Jian-Yan Wei , Betrand Cordier

We report multiple epoch VLA/JVLA observations of 89 northern hemisphere sources, most with 37\,GHz flux density > 1 Jy, observed at 4.8, 8.5, 33.5, and 43.3 GHz. The high frequency selection leads to a predominantly flat spectrum sample,…

Cosmology and Nongalactic Astrophysics · Physics 2013-01-21 Noah Kurinsky , Anna Sajina , Bruce Partridge , Steve Myers , Xi Chen , Marcos López-Caniego

Knowledge of the population of radio sources in the range ~2-200 GHz is important for understanding their effects on measurements of the Cosmic Microwave Background power spectrum. We report measurements of the 30 GHz flux densities of 605…

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