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Sgr A* Region Compact Radio Source Catalog

Metadata Updated: September 19, 2025

Recent broad-band 34- and 44-GHz radio continuum observations of the Galactic center have revealed 41 massive stars identified with near-IR (NIR) counterparts, as well as 44 proplyd candidates within 30 arcseconds of Sgr A. Radio observations obtained in 2011 and 2014 have been used to derive proper motions of eight young stars near Sgr A. The accuracy of proper motion estimates based on NIR observations by Lu et al. (2009, ApJ, 690, 1463) and Paumard et al. (2006, ApJ, 643, 1011) have been investigated by using their proper motions to predict the 2014 epoch positions of NIR stars and comparing the predicted positions with those of radio counterparts in the 2014 radio observations. Predicted positions from Lu et al. show an rms scatter of 6 milliarcseconds (mas) relative to the radio positions, while those from Paumard et al. show rms residuals of 20 mas. In the reference paper, the authors also determine the mass-loss rates of 11 radio stars, finding rates that are on average ~2 times smaller than those determined from model atmosphere calculations and NIR data. Clumpiness of ionized winds would reduce the mass loss rate of WR and O stars by additional factors of 3 and 10, respectively. One important implication of this is a reduction in the expected mass accretion rate onto Sgr A from stellar winds by nearly an order of magnitude to a value of a few x 10<sup>-7</sup> solar masses per year. The authors carried out A-array observations of the Galactic center region (VLA program 14A-232) in the Ka (9 mm, 34.5 GHz) band on 2014 March 9 in which they detected 318 compact radio sources within 30" of Sgr A. The authors searched for NIR counterparts to these compact radio sources using high-angular resolution AOs-assisted imaging observations acquired with the VLT/NACO. A K<sub>s</sub>-band (central wavelength 2.18 micron) image was obtained in a rectangular dither pattern on 2012 September 12. L'-band (3.8 micron) observations were obtained during various observing runs between 2012 June and September. The authors found that 45 of the compact radio sources had stellar counterparts in the K<sub>s</sub> and L' bands. This table contains the details of the 318 compact radio sources detected at 34.5 GHz and their NIR counterparts. This table was created by the HEASARC in November 2016 based on CDS table J/ApJ/809/10, file table6.dat. This is a service provided by NASA HEASARC .

Access & Use Information

Public: This dataset is intended for public access and use. License: No license information was provided. If this work was prepared by an officer or employee of the United States government as part of that person's official duties it is considered a U.S. Government Work.

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Dates

Metadata Created Date April 11, 2025
Metadata Updated Date September 19, 2025

Metadata Source

Harvested from NASA Data.json

Additional Metadata

Resource Type Dataset
Metadata Created Date April 11, 2025
Metadata Updated Date September 19, 2025
Publisher High Energy Astrophysics Science Archive Research Center
Maintainer
Identifier ivo://nasa.heasarc/sgraregcsc
Data Last Modified 2025-09-10
Category Astrophysics
Public Access Level public
Bureau Code 026:00
Metadata Context https://project-open-data.cio.gov/v1.1/schema/catalog.jsonld
Schema Version https://project-open-data.cio.gov/v1.1/schema
Catalog Describedby https://project-open-data.cio.gov/v1.1/schema/catalog.json
Harvest Object Id 6bb9e889-7561-4fdd-9fdf-ad53a5e3203c
Harvest Source Id 58f92550-7a01-4f00-b1b2-8dc953bd598f
Harvest Source Title NASA Data.json
Homepage URL https://heasarc.gsfc.nasa.gov/W3Browse/all/sgraregcsc.html
Program Code 026:000
Source Datajson Identifier True
Source Hash e335e3120c05623b35b42989a59e30f0ee98dbc87b7b042b5b89389244e4645f
Source Schema Version 1.1

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