Related papers: Differential Astrometry over 15 degrees

Building the radio sky template are crucial for detecting the 21 cm emission line signal from the Epoch of Reionization (EoR), as well as for other cosmological research endeavors. Utilizing data from the LOFAR Two-meter Sky Survey (LoTSS)…

Radio-detection is becoming an established technique for the detection of air showers induced by cosmic particles. This is in particular true at the highest energies, where very large detection areas are required. A proper description of…

Extensive air showers still are our only access to the highest-energy particles in the universe, namely cosmic-ray nuclei with energies up to several 100 EeV. Studying open questions in cosmic-ray physics, like their yet unknown origin…

Metric and decametric radio-emissions from the Sun are the only direct source of information about the dynamics of non-thermal electrons in the upper corona. In addition, the combination of spectral and imaging (sizes, shapes, and…

We present Very Large Array (VLA) observations at 1.4 GHz and 5 GHz of a sample of 12 Quasi-stellar Objects (QSOs) at z = 3.99 to 4.46. The sources were selected as the brightest sources at 250 GHz from the recent survey of Omont et al.…

When VLBI observations are used to determine the position or motion of a radio source relative to reference sources nearby on the sky, the astrometric information is usually obtained via: (i) phase-referenced maps; or (ii) parametric model…

Using the Navy Precision Optical Interferometer, we measured the angular diameters of 10 stars that have previously measured solar-like oscillations. Our sample covered a range of evolutionary stages but focused on evolved subgiant and…

In order to find more examples of the elusive high-redshift molecular absorbers, we have embarked on a systematic discovery program for highly obscured, radio-loud "invisible AGN" using the VLA Faint Images of the Radio Sky at Twenty…

We present a milliarcsecond-resolution radio survey of 17 high-redshift (4 < z < 5.4) blazar candidates observed with the European Very Long Baseline Interferometry (VLBI) Network at 5 GHz. The primary objective of this study was to…

We report on the present status of our S5 polar cap phase-connected astrometry program. We observe 13 radio sources in the northernmost 20deg of the sky at the wavelengths of 3.6cm and 2cm, and we plan to extend the program to 0.7cm. We…

Compact galactic and extragalactic radio sources can be imaged with an unsurpassed angular resolution of a few ten micro-arcseconds, adopting the observing technique of global millimeter VLBI. Here we present the Global Millimeter VLBI…

A modern Q-band low noise amplifier (LNA) front-end is being fitted to the 10.4 m millimeter-wave telescope at the Raman Research Institute (RRI) to support observations in the 40-50 GHz frequency range. To assess the suitability of the…

Very Long Baseline Interferometry (VLBI) astrometry is a well established technique for achieving $\pm10~\mu$as parallax accuracies at frequencies well above 10~GHz. At lower frequencies, uncompensated interferometer delays associated with…

Using the filled bolometer array SHARC-II on the Caltech Submillimeter Observatory (CSO), we have obtained deep (rms ~ 15mJy/beam), high-quality 350 micron maps of five of the most luminous high-z radio galaxies known. In all cases the…

We present the initial sample of redshifts for 3,839 galaxies in the MeerKAT DEEP2 field -- the deepest $\sim$1.4\,GHz radio field yet observed. Using a spectrophotometric technique combining coarse optical spectra with broadband…

Digital radio arrays have become an effective tool to measure air showers at energies around and above 100 PeV. Compared to optical techniques, the radio technique is not restricted to clear nights. Thanks to recent progress on…

We used radio source catalogues accessible from the CATS database (http://cats.sao.ru) to establish radio continuum spectra for decametric radio sources in the UTR-2 catalogue (Braude et al., 1978--1994). From these, we select a sample of…

The paper presents the results of the largest to date VLBI absolute astrometry campaign of observations of 13,645 radio sources with the Very Long Baseline Array (VLBA). Of them, 7220 have been detected, including 6755 target sources that…

We present the results from two radio integrations at 8.4 GHz using the VLA. One of the fields, at 13h,+43d (SA13 field), has an rms noise level of 1.49 microJy and is the deepest radio image yet made. Thirty-four sources in a complete…

We present millimeter wavelength detections of three faint sources that are most likely high-redshift starburst galaxies. For one of the sources, which was previously discovered with SCUBA at 850 mu m, we present a detection with the IRAM…