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相关论文: The 74MHz System on the Very Large Array

200 篇论文

Accurate calibration of data is essential for the current generation of CMB experiments. Using data from the Very Small Array (VSA), we describe procedures which will lead to an accuracy of 1 percent or better for experiments such as the…

We have used the Very Large Array (VLA), linked with the Pie Town Very Long Baseline Array antenna, to determine astrometric positions of 46 radio stars in the International Celestial Reference Frame (ICRF). Positions were obtained in the…

天体物理学 · 物理学 2008-11-26 D. A. Boboltz , A. L. Fey , W. K. Puatua , N. Zacharias , M. J. Claussen , K. J. Johnston , R. A. Gaume

We present new Very Large Array (VLA) radio images at 74 and 324 MHz of the SNR W44. The VLA images, obtained with unprecedented angular resolution and sensitivity for such low frequencies have been used in combination with existing 1442…

天体物理学 · 物理学 2009-11-13 G. Castelletti , G. Dubner , C. Brogan , N. E. Kassim

We present a method for absolute calibration of received radio-frequency in the ultra low frequency (ULF), and very low frequency (VLF) range. This is achieved with the use of a radio frequency optically pumped magnetometer (RF-OPM). We…

In this paper we present the results of a survey for radio transients using data obtained from the Very Large Array archive. We have reduced, using a pipeline procedure, 5037 observations of the most common pointings - i.e. the calibrator…

We present a new method to study harmonic waves in the low ionosphere (60 - 90 km) by detecting their effects on reflection of very low frequency (VLF) radio waves. Our procedure is based on amplitude analysis of reflected VLF radio waves…

地球与行星天体物理 · 物理学 2017-05-04 Aleksandra Nina , Vladimir Cadez

The Laser Interferometer Space Antenna (LISA) will enable direct observations of low-frequency gravitational waves, offering unprecedented insight into astrophysical and cosmological phenomena. LISA's heterodyne interferometric measurement…

仪器与探测器 · 物理学 2025-08-26 Gerhard Heinzel , Javier Álvarez-Vizoso , Miguel Dovale-Álvarez

In almost 30 years of operation, the Very Large Array (VLA) has proved to be a remarkably flexible and productive radio telescope. However, the basic capabilities of the VLA have changed little since it was designed. A major expansion…

天体物理仪器与方法 · 物理学 2015-05-14 R. Perley , P. Napier , J. Jackson , B. Butler , B. Carlson , D. Fort , P. Dewdney , B. Clark , R. Hayward , S. Durand , M. Revnell , M. McKinnon

We present the results of the first successful observations of the Pie Town link with the Very Large Array (VLA) at 74 MHz on Hercules A. The improvement in resolution from 25 arcsec to 10 arcsec resolves the helical- and ring-like features…

天体物理学 · 物理学 2009-11-10 Nectaria A. B. Gizani , A. Cohen , N. E. Kassim

The LOw-Frequency ARray (LOFAR) is used to make precise measurements of radio emission from extensive air showers, yielding information about the primary cosmic ray. Interpreting the measured data requires an absolute and…

Accurate primary beam calibration is essential for precise brightness measurements in radio astronomy. The VLA Low-band Ionosphere and Transient Experiment (VLITE) faces challenges in calibration due to the offset Cassegrain optics used in…

天体物理仪器与方法 · 物理学 2024-12-20 Emil Polisensky , Tracy E. Clarke , Simona Giacintucci , Wendy Peters

The Low Frequency Array (LOFAR) is a new generation of electronic radio telescope based on aperture array technology. The telescope is being developed by ASTRON, and currently being rolled out across the Netherlands and other countries in…

宇宙学与河外天体物理 · 物理学 2009-03-07 M. A. Garrett , H. Rampadarath , E. Lenc , Olaf Wucknitz

The largely unexplored decameter radio band (10-30 MHz) provides a unique window for studying a range of astronomical topics, such as auroral emission from exoplanets, inefficient cosmic ray acceleration mechanisms, fossil radio plasma, and…

We have used the Very Large Array(VLA) in C configuration to carry out a sensitive 20cm radio survey of regions of sky that have been surveyed in the Far Infra-Red over the wavelength range 5-200 microns with ISO as part of the European…

Massive MIMO has been the subject of intense interest in both academia and industry for the past few years. 3GPP standardization for cellular systems have adopted the principles of massive MIMO and categorized the use of large rectangular…

We present results from four years of twice-weekly 15 GHz radio monitoring of about 1500 blazars with the Owens Valley Radio Observatory 40 m telescope. Using the intrinsic modulation index to measure variability amplitude, we find that,…

As a service to the community, we have compiled radio frequency spectra from the literature for all sources within the VLA Low Frequency Sky Survey (VLSS) that are brighter than 15 Jy at 74 MHz. Over 160 references were used to maximize the…

天体物理学 · 物理学 2009-11-13 J. F. Helmboldt , N. E. Kassim , A. S. Cohen , W. M. Lane , T. J. Lazio

We describe a new method which achieves high precision Very Long Baseline Interferometry (VLBI) astrometry in observations at millimeter wavelengths. It combines fast frequency-switching observations, to correct for the dominant…

天体物理仪器与方法 · 物理学 2015-05-27 Maria J. Rioja , Richard Dodson