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Related papers: Radio variability and non-thermal components in st…

200 papers

Using a combination of radio and optical imaging at 0.1\arcs to 0.2\arcs resolution with the VLA/MERLIN and HST has led to a breakthrough in our understanding of radio emission from distant (0.1<z<3) starburst galaxies. We have recently…

Astrophysics · Physics 2007-05-23 E. A. Richards , F. E. Bauer , A. J. Barger , L. Cowie

We present results on the emission-line properties of z=1.4-7.5 star-forming galaxies in the Assembly of Ultradeep Rest-optical Observations Revealing Astrophysics (AURORA) Cycle 1 JWST/NIRSpec program. Based on its depth, continuous…

Aims: We provide new insights into the gamma-ray emission from HESS J1912+101, a TeV supernova remnant candidate probably associated with the radio pulsar PSR J1913+1011. Methods: We obtained new observations at 1.5 GHz using the VLA in the…

High Energy Astrophysical Phenomena · Physics 2023-04-26 Laura Duvidovich , Alberto Petriella

We present 5.5 GHz observations with the VLA of a sample of nearby galaxies with energetic nuclear outbursts at mid-infrared (MIR) bands. These observations reach a uniform depth down to a median rms of ~10 uJy, representing one of most…

High Energy Astrophysical Phenomena · Physics 2020-06-24 B. B. Dai , X. W. Shu , N. Jiang , L. M. Dou , D. Z. Liu , C. W. Yang , F. B. Zhang , T. G. Wang

We present 33 GHz imaging for 112 pointings towards galaxy nuclei and extranuclear star-forming regions at $\approx$2" resolution using the Karl G. Jansky Very Large Array (VLA) as part of the Star Formation in Radio Survey. A comparison…

Astrophysics of Galaxies · Physics 2018-02-14 E. J. Murphy , D. Dong , E. Momjian , S. Linden , R. C. Kennicutt, , D. S. Meier , E. Schinnerer , J. L. Turner

We have monitored over a ten-year interval the light variations of five evolved stars with very large mid-infrared excesses. All five objects appear to have oxygen-rich or mixed oxygen-rich and carbon-rich chemistries. They all vary in…

Solar and Stellar Astrophysics · Physics 2020-08-04 Bruce J. Hrivnak , Gary Henson , Todd C. Hillwig , Wenxian Lu , Kristie A. Nault , Kevin Volk

We describe an observational program aimed at understanding the radio emission from distant, rapidly evolving galaxy populations. These observations were carried out at 1.4 and 8.5 GHz with the VLA centered on the Hubble Deep Field,…

Astrophysics · Physics 2009-10-31 E. A. Richards

The extremely accurate estimates of stellar variability and radial velocity in the Gaia Data Release 3 (Gaia DR3) have enabled us to examine the close binarity and radial velocity (RV) of central stars (CSs) of planetary nebulae (PNe). This…

Solar and Stellar Astrophysics · Physics 2023-04-05 A. Ali , A. Mindil

We perform a stacking analysis of H-ATLAS data in order to obtain isothermal dust temperatures and rest-frame luminosities at 250um (L250), for 1599 radio sources over the H-ATLAS P1 GAMA area. The radio sample is generated using a…

Fast Radio Bursts are bright, unresolved, non-repeating, broadband, millisecond flashes, found primarily at high Galactic latitudes, with dispersion measures much larger than expected for a Galactic source. The inferred all-sky burst rate…

Comparison of 8.4-GHz radio images of a sample of 11 early-type Seyfert galaxies with previous observations reveals possible variation in the nuclear radio flux density in 5 of them over a 7-yr period. We find no correlation between radio…

Cosmology and Nongalactic Astrophysics · Physics 2009-09-28 C. G. Mundell , P. Ferruit , N. Nagar , A. S. Wilson

Observations with the Karl G. Jansky Very Large Array at 46 GHz (7 mm) have been used to measure the size and shape of the radio photospheres of four long-period variable stars: R Leonis (R Leo), IRC+10216 (CW Leo), chi Cygni (chi Cyg), and…

Solar and Stellar Astrophysics · Physics 2018-07-04 L. D. Matthews , M. J. Reid , K. M. Menten , K. Akiyama

From Very Long Baseline Array (VLBA) observations we previously identified a population of 123 young stellar systems with nonthermal radio emission toward the core of the Orion Nebula Cluster (ONC). We find optical sources in the Gaia DR2…

Solar and Stellar Astrophysics · Physics 2021-01-13 Sergio A. Dzib , Jan Forbrich , Mark J. Reid , Karl M. Menten

The Galactic center Arches stellar cluster, detected and studied until now only in the near-infrared, is comprised of at least one hundred massive (M>20 Msun) stars. Here we report the detection at centimeter wavelengths of radio continuum…

Astrophysics · Physics 2009-11-06 Cornelia C. Lang , W. M. Goss , Luis F. Rodriguez

The Coronet Cluster in the nearby R CrA dark cloud offers the rare opportunity to study at least four "class I" protostellar sources as well as one candidate "class 0" source, a Herbig Ae star, and a candidate brown dwarf within a few…

Astrophysics · Physics 2009-11-11 Jan Forbrich , Thomas Preibisch , Karl M. Menten

RX J1301.9+2747 is a unique active galaxy with supersoft X-ray spectrum that lacks significant emission at energies above 2 keV. In addition, it is one of few galaxies displaying quasi-periodic X-ray eruptions that recur on a timescale of…

We are studying a class of binary post-AGB stars that seem to be systematically surrounded by equatorial disks and slow outflows. Although the rotating dynamics had only been well identified in three cases, the study of such structures is…

Solar and Stellar Astrophysics · Physics 2018-06-13 V. Bujarrabal , A. Castro-Carrizo , H. Van Winckel , J. Alcolea , C. Sanchez Contreras , M. Santander-Garcia , M. Hillen

In order to investigate the relationship between the local environment and the properties of natal star clusters, we obtained radio observations of 25 star-forming galaxies within 20 Mpc using the Very Large Array (VLA) and the Australia…

Astrophysics of Galaxies · Physics 2011-03-11 Alan Aversa , Kelsey Johnson , Crystal Brogan , W. Goss , D. J. Pisano

In this paper, we present the analysis of incoherent non-thermal radio emission from a sample of hot magnetic stars, ranging from early-B to early-A spectral type. Spanning a wide range of stellar parameters and wind properties, these stars…

Context: Some O stars are suspected to have to have (weak) magnetic fields because of the observed cyclical variability in their UV wind-lines. However, direct detections of these magnetic fields using optical spectropolarimetry have proven…