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Related papers: The Australian experience with the PC-EVN recorder

200 papers

We investigate the position of the radio core in a blazar by multi-epoch astrometric observations at 43 GHz. Using the VLBI Exploration of Radio Astrometry (VERA), we have conducted four adjacent observations in February 2011 and another…

High Energy Astrophysical Phenomena · Physics 2015-06-23 S. Koyama , M. Kino , A. Doi , K. Niinuma , K. Hada , H. Nagai , M. Honma , K. Akiyama , M. Giroletti , G. Giovannini , M. Orienti , N. Isobe , J. Kataoka , D. Paneque , H. Kobayashi , K. Asada

Observations of the starburst galaxy, M82, have been made with a 20-station global VLBI array at $\lambda$18cm. Maps are presented of the brightest young supernova remnants (SNR) in M82 and the wide-field mapping techniques used in making…

We present measurements of the total radio flux density as well as very-long-baseline interferometry (VLBI) images of the star, IM Pegasi, which was used as the guide star for the NASA/Stanford relativity mission Gravity Probe B. We…

Instrumentation and Methods for Astrophysics · Physics 2015-06-04 M. F. Bietenholz , N. Bartel , D. E. Lebach , R. R. Ransom , M. I. Ratner , I. I. Shapiro

We report on very long baseline interferometry (VLBI) observations of the radio emission from the inner region of the Crab Nebula, made at 1.6 GHz and 5 GHz after a recent high-energy flare in this object. The 5 GHz data have provided only…

High Energy Astrophysical Phenomena · Physics 2015-05-28 A. P. Lobanov , D. Horns , T. W. B. Muxlow

Long baseline radio interferometers can provide some interesting opportunities for future SETI searches. Known advantages (compared to single dishes or beam-formed arrays), include the large reduction in false-positives due to the…

Instrumentation and Methods for Astrophysics · Physics 2018-10-18 M. A. Garrett

The space astrometry mission GAIA will construct a dense optical QSO-based celestial reference frame. For consistency between optical and radio positions, it will be important to align the GAIA frame and the International Celestial…

Astrophysics · Physics 2008-12-18 G. Bourda , P. Charlot , R. Porcas , S. Garrington

High precision astrometric Space Very Long Baseline Interferometry (S-VLBI) at the low end of the conventional frequency range, i.e. 20cm, is a requirement for a number of high priority science goals. These are headlined by obtaining…

Instrumentation and Methods for Astrophysics · Physics 2015-06-15 R. Dodson , M. Rioja , Y. Asaki , H. Imai , X. -Y. Hong , Z. Shen

A second generation near-term space VLBI mission, VSOP-2, is being planned for a launch in 2010 or soon after. The scientific objectives are very high angular resolution imaging of astrophysically exotic regions, including the cores, jets,…

Astrophysics · Physics 2007-05-23 H. Hirabayashi , Y. Murata , P. G. Edwards , Y. Asaki , N. Mochizuki , M. Inoue , T. Umemoto , S. Kameno , Y. Kono

We present results of EVN observations of eleven GHz-Peaked-Spectrum (GPS) radio sources at 2.3/8.4 GHz. These sources are from the classical ''bright'' GPS source samples with peak flux densities $>$ 0.2 Jy and spectral indices $\alpha <…

Astrophysics · Physics 2007-05-23 L. Xiang , D. Dallacasa , P. Cassaro , D. Jiang , C. Reynolds

We present the outlines of a new microcontroller based data acquisition system which is aimed for reliable operation in a typical cosmic ray particle registration experiment. The system supports connection of up to 16 input signals and…

Instrumentation and Detectors · Physics 2018-08-29 Alexander Shepetov , Alexander Chubenko , Olga Kryakunova , Nikolay Nikolayevsky , Nazyf Salikhov , Victor Yanke

Space Very Long Baseline Interferometry is a radio astronomy technique distinguished by a record-high angular resolution reaching single-digit microseconds of arc. The paper provides a brief account of the history of developments of this…

Instrumentation and Methods for Astrophysics · Physics 2023-12-27 Leonid I. Gurvits

We present a description of the Prototype All-Sky Imager (PASI), a backend correlator and imager of the first station of the Long Wavelength Array (LWA1). PASI cross-correlates a live stream of 260 dual-polarization dipole antennas of the…

Instrumentation and Methods for Astrophysics · Physics 2015-03-18 K. S. Obenberger , G. B. Taylor , J. M. Hartman , T. E. Clarke , J. Dowell , A. Dubois , D. Dubois , P. A. Henning , J. Lazio , S. Michalak , F. K. Schinzel

The Very Large Array (VLA) Low-frequency Sky Survey (VLSS) has imaged 95% of the 3*pi sr of sky north of declination = -30 degrees at a frequency of 74 MHz (4 meter wavelength). The resolution is 80" (FWHM) throughout, and the typical RMS…

Continuous burst mode VLF measurements were recorded on the RBSP/Van Allen Probes satellites and are analyzed to detect pulses from the Russian Alpha (RSDN-20) ground-based navigational system. Based on the wave characteristics of these…

In this paper, we propose a novel memory-enabled non-uniform sampling-based bumblebee foraging algorithm (MEB) designed for optimal channel selection in a distributed Vehicular Dynamic Spectrum Access (VDSA) framework employed in a platoon…

Networking and Internet Architecture · Computer Science 2023-02-02 Kuldeep S. Gill , Pawel Kryszkiewicz , Pawel Sroka , Adrian Kliks , Alexander M. Wyglinski

VLBI at millimeter wavelengths (mm-VLBI) allows the detailed imaging of compact galactic and extragalactic radio sources with micro-arcsecond scale resolution, unaccessible by other observing techniques. Here we discuss the scientific…

Astrophysics · Physics 2007-05-23 T. P Krichbaum , A. Witzel , J. A. Zensus

A "large-N" correlator that makes use of Field Programmable Gate Arrays and Graphics Processing Units has been deployed as the digital signal processing system for the Long Wavelength Array station at Owens Valley Radio Observatory…

ESA's Envisat mission carried a RA-2 radar altimeter since its launch in 2002 to sense sea state and especially measure sea surface height (SSH). The onboard processing combined multiple echoes incoherently to reduce Speckle noise and…

Atmospheric and Oceanic Physics · Physics 2023-07-14 R. Abileah , J. Gomez-Enri , A. Scozzari , S. Vignudelli

There are at least four well known Very Long Baseline Interferometer (VLBI) networks that provide open access to astronomers around the world. These include the EVN, VLBA, CMVA and APT/LBA. In this paper I have chosen to focus on a sub-set…

Astrophysics · Physics 2007-05-23 M. A. Garrett

CMOS detectors offer many advantages over CCDs for optical and UV astronomical applications, especially in space where high radiation tolerance is required. However, astronomical instruments are most often designed for low light-level…

Instrumentation and Methods for Astrophysics · Physics 2022-03-31 Timothee Greffe , Roger Smith , Myles Sherman , Fiona Harrison , Hannah Earnshaw , Brian Grefenstette , John Hennessy , Shouleh Nikzad
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