The MAVERIC Survey: Radio Catalogs and Source Counts from Deep Very Large Array Imaging of 25 Galactic Globular Clusters

The MAVERIC survey is the first deep radio continuum imaging survey of Milky Way globular clusters, with a central goal of finding and classifying accreting compact binaries, including stellar-mass black holes. Here we present radio source catalogs for 25 clusters with ultra-deep Karl G. Jansky Very...

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Main Authors: Shishkovsky, L., Strader, J., Chomiuk, L., Tremou, E., Tudor, V., Miller-Jones, James, Bahramian, Arash, Heinke, C.O., Maccarone, T.J., Sivakoff, G.R.
Format: Journal Article
Language:English
Published: IOP PUBLISHING LTD 2020
Subjects:
Online Access:http://purl.org/au-research/grants/arc/FT140101082
http://hdl.handle.net/20.500.11937/90035
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author Shishkovsky, L.
Strader, J.
Chomiuk, L.
Tremou, E.
Tudor, V.
Miller-Jones, James
Bahramian, Arash
Heinke, C.O.
Maccarone, T.J.
Sivakoff, G.R.
author_facet Shishkovsky, L.
Strader, J.
Chomiuk, L.
Tremou, E.
Tudor, V.
Miller-Jones, James
Bahramian, Arash
Heinke, C.O.
Maccarone, T.J.
Sivakoff, G.R.
author_sort Shishkovsky, L.
building Curtin Institutional Repository
collection Online Access
description The MAVERIC survey is the first deep radio continuum imaging survey of Milky Way globular clusters, with a central goal of finding and classifying accreting compact binaries, including stellar-mass black holes. Here we present radio source catalogs for 25 clusters with ultra-deep Karl G. Jansky Very Large Array observations. The median observing time was 10 hr per cluster, resulting in typical rms sensitivities of 2.3 and 2.1 μJy per beam at central frequencies of 5.0 and 7.2 GHz, respectively. We detect nearly 1300 sources in our survey at 5σ, and while many of these are likely to be background sources, we also find strong evidence for an excess of radio sources in some clusters. The radio spectral index distribution of sources in the cluster cores differs from the background, and shows a bimodal distribution. We tentatively classify the steep-spectrum sources (those much brighter at 5.0 GHz) as millisecond pulsars and the flat-spectrum sources as compact or other kinds of binaries. These provisional classifications will be solidified with the future addition of X-ray and optical data. The outer regions of our images represent a deep, relatively wide-field (∼0.4 deg2) and high-resolution C band background survey, and we present source counts calculated for this area. We also release radio continuum images for these 25 clusters to the community.
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spelling curtin-20.500.11937-900352023-02-07T06:14:38Z The MAVERIC Survey: Radio Catalogs and Source Counts from Deep Very Large Array Imaging of 25 Galactic Globular Clusters Shishkovsky, L. Strader, J. Chomiuk, L. Tremou, E. Tudor, V. Miller-Jones, James Bahramian, Arash Heinke, C.O. Maccarone, T.J. Sivakoff, G.R. Science & Technology Physical Sciences Astronomy & Astrophysics Globular star clusters Radio source counts Surveys X-ray binary stars Radio pulsars Radio sources MASS BLACK-HOLES X-RAY SOURCES MILLISECOND PULSARS SOURCE POPULATION NEUTRON-STAR FIELD-SOUTH EMISSION CONTINUUM CHANDRA BINARIES The MAVERIC survey is the first deep radio continuum imaging survey of Milky Way globular clusters, with a central goal of finding and classifying accreting compact binaries, including stellar-mass black holes. Here we present radio source catalogs for 25 clusters with ultra-deep Karl G. Jansky Very Large Array observations. The median observing time was 10 hr per cluster, resulting in typical rms sensitivities of 2.3 and 2.1 μJy per beam at central frequencies of 5.0 and 7.2 GHz, respectively. We detect nearly 1300 sources in our survey at 5σ, and while many of these are likely to be background sources, we also find strong evidence for an excess of radio sources in some clusters. The radio spectral index distribution of sources in the cluster cores differs from the background, and shows a bimodal distribution. We tentatively classify the steep-spectrum sources (those much brighter at 5.0 GHz) as millisecond pulsars and the flat-spectrum sources as compact or other kinds of binaries. These provisional classifications will be solidified with the future addition of X-ray and optical data. The outer regions of our images represent a deep, relatively wide-field (∼0.4 deg2) and high-resolution C band background survey, and we present source counts calculated for this area. We also release radio continuum images for these 25 clusters to the community. 2020 Journal Article http://hdl.handle.net/20.500.11937/90035 10.3847/1538-4357/abb880 English http://purl.org/au-research/grants/arc/FT140101082 http://creativecommons.org/licenses/by/4.0/ IOP PUBLISHING LTD fulltext
spellingShingle Science & Technology
Physical Sciences
Astronomy & Astrophysics
Globular star clusters
Radio source counts
Surveys
X-ray binary stars
Radio pulsars
Radio sources
MASS BLACK-HOLES
X-RAY SOURCES
MILLISECOND PULSARS
SOURCE POPULATION
NEUTRON-STAR
FIELD-SOUTH
EMISSION
CONTINUUM
CHANDRA
BINARIES
Shishkovsky, L.
Strader, J.
Chomiuk, L.
Tremou, E.
Tudor, V.
Miller-Jones, James
Bahramian, Arash
Heinke, C.O.
Maccarone, T.J.
Sivakoff, G.R.
The MAVERIC Survey: Radio Catalogs and Source Counts from Deep Very Large Array Imaging of 25 Galactic Globular Clusters
title The MAVERIC Survey: Radio Catalogs and Source Counts from Deep Very Large Array Imaging of 25 Galactic Globular Clusters
title_full The MAVERIC Survey: Radio Catalogs and Source Counts from Deep Very Large Array Imaging of 25 Galactic Globular Clusters
title_fullStr The MAVERIC Survey: Radio Catalogs and Source Counts from Deep Very Large Array Imaging of 25 Galactic Globular Clusters
title_full_unstemmed The MAVERIC Survey: Radio Catalogs and Source Counts from Deep Very Large Array Imaging of 25 Galactic Globular Clusters
title_short The MAVERIC Survey: Radio Catalogs and Source Counts from Deep Very Large Array Imaging of 25 Galactic Globular Clusters
title_sort maveric survey: radio catalogs and source counts from deep very large array imaging of 25 galactic globular clusters
topic Science & Technology
Physical Sciences
Astronomy & Astrophysics
Globular star clusters
Radio source counts
Surveys
X-ray binary stars
Radio pulsars
Radio sources
MASS BLACK-HOLES
X-RAY SOURCES
MILLISECOND PULSARS
SOURCE POPULATION
NEUTRON-STAR
FIELD-SOUTH
EMISSION
CONTINUUM
CHANDRA
BINARIES
url http://purl.org/au-research/grants/arc/FT140101082
http://hdl.handle.net/20.500.11937/90035