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We present radio images within 30$''$ of Sgr A* based on recent VLA observations at 34 GHz with 7.8 microJy sensitivity and resolution $\sim88\times46$ milliarcseconds (mas). We report 44 partially resolved compact sources clustered in two…

Astrophysics of Galaxies · Physics 2015-06-23 F. Yusef-Zadeh , D. A. Roberts , M. Wardle , W. Cotton , R. Schödel , M. J. Royster

Images of neutral Hydrogen 21cm absorption and radio continuum emission at 1.4 GHz from Mrk 273 were made using the Very Long Baseline Array and Very Large Array. These images reveal a gas disk associated with the northern nuclear region…

Astrophysics · Physics 2009-10-31 C. L. Carilli , G. B. Taylor

Ultracompact and hypercompact HII regions appear when a star with a mass larger than about 15 solar masses starts to ionize its own environment. Recent observations of time variability in these objects are one of the pieces of evidence that…

Astrophysics of Galaxies · Physics 2015-05-28 Roberto Galván-Madrid , Thomas Peters , Eric Keto , Mordecai-Mark Mac Low , Robi Banerjee , Ralf S. Klessen

We present results of a study of neutral hydrogen (HI) in a complete sample of nearby non-cluster radio galaxies. We find that radio galaxies with large amounts of extended HI (M_HI >= 10^9 M_solar) all have a compact radio source. The host…

Among radio galaxies, compact sources are a class of objects not yet well understood, and most of them cannot be included in classical populations of compact radio sources (flat spectrum AGN or compact steep spectrum sources). Our main goal…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 E. Liuzzo , S. Buttiglione , G. Giovannini , M. Giroletti , S. Capetti , G. B. Taylor

Giant gaseous layers (termed "superdisk") have been hypothesized in the past to account for the strip-like radio emission gap (or straight-edged central brightness depression) observed between the twin radio lobes, in over a dozen…

Astrophysics of Galaxies · Physics 2021-01-13 Abhijeet Anand , Nirupam Roy , Gopal-Krishna

We present theoretical predictions for the free-free emission at cm wavelengths obtained from photoevaporation and MHD wind disk models adjusted to the case of the TW Hydrae young stellar object. For this system, disk photoevaporation with…

Earth and Planetary Astrophysics · Physics 2021-06-09 Luca Ricci , Sarah Harter , Barbara Ercolano , Michael Weber

Aims: Our aim was to measure and characterize the short-wavelength radio emission from young stellar objects (YSOs) in the Orion Nebula Cluster and the BN/KL star-forming region. Methods: We used the NRAO Very Large Array at a wavelength of…

Astrophysics · Physics 2009-11-13 Jan Forbrich , Karl M. Menten , Mark J. Reid

We present Very Large Array continuum observations made at 8.3 GHz toward the dense core B59, in the Pipe Nebula. We detect six compact sources, of which five are associated with the five most luminous sources at 70 micrometer in the…

Solar and Stellar Astrophysics · Physics 2013-08-13 Sergio A. Dzib , Luis F. Rodriguez , Anabella T. Araudo , Laurent Loinard

Multi-wavelength VLA observations of two extended radio galaxies, 0235-197 and 1203+043 are presented. There is some evidence from earlier studies that these two sources exhibit low frequency (<1 GHz) variability. This work shows that both…

Astrophysics · Physics 2009-10-31 W. Junor , F. Mantovani , R. Morganti , L. Padrielli

We present a catalog of radio sources of the M 17 region based on deep X band radio observations centered at 10 GHz obtained with the Jansky Very Large Array in the A configuration. We detect a total of 194 radio sources, 12 of them…

We present new sub-arcsecond-resolution Karl G. Jansky Very Large Array (VLA) imaging at 10 GHz of 155 ultra-luminous ($L_{\rm bol}\sim10^{11.7-14.2} L_\odot$) and heavily obscured quasars with redshifts $z \sim0.4-3$. The sample was…

We present deep polarimetric observations at 154 MHz with the Murchison Widefield Array (MWA), covering 625 deg^2 centered on RA=0 h, Dec=-27 deg. The sensitivity available in our deep observations allows an in-band, frequency-dependent…

We present new Very Long Baseline Array (VLBA) imaging of a MHz-peaked spectrum (MPS) source that was found using commensal low-frequency data taken with the Karl G. Jansky Very Large Array (VLA). The source, J0330-2730, was identified in…

In this work, we have carried out a systematic analysis of the VLASS quick look catalogs together with \textit{Gaia DR3} to identify the optical counterparts of 3~GHz radio emitters within 500~pc to obtain a homogeneous statistical sample…

Searching for variability, we have observed a sample of hot post-AGB stars and young Planetary Nebulae candidates with the Very Large Array at 4.8, 8.4, and 22.4 GHz. The sources had been previously detected in the radio continuum, which is…

Solar and Stellar Astrophysics · Physics 2015-05-20 L. Cerrigone , C. Trigilio , G. Umana , C. S. Buemi , P. Leto

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…

Radio observations from space allow to characterize solar radio bursts below the ionospheric cutoff, which are otherwise inaccessible, but suffer from low, insufficient temporal resolution. In this Letter we present novel, high-temporal…

Solar and Stellar Astrophysics · Physics 2024-10-25 Antonio Vecchio , Milan Maksimovic , Nicolina Chrysaphi , Eduard P. Kontar , Vratislav Krupar

OH is a key species in the water chemistry of star-forming regions, because its presence is tightly related to the formation and destruction of water. This paper presents OH observations from 23 low- and intermediate-mass young stellar…

We present a multiwavelength study of the ultra compact HII region associated with IRAS 20178+4046. This enables us to probe the different components associated with this massive star forming region. The radio emission from the ionized gas…

Astrophysics · Physics 2009-11-13 A. Tej , S. K. Ghosh , V. K. Kulkarni , D. K. Ojha , R. P. Verma , S. Vig