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Title: THE CONTRIBUTION OF RADIO GALAXY CONTAMINATION TO MEASUREMENTS OF THE SUNYAEV-ZEL'DOVICH DECREMENT IN MASSIVE GALAXY CLUSTERS AT 140 GHz WITH BOLOCAM

Abstract

We describe in detail our characterization of the compact radio source population in 140 GHz Bolocam observations of a set of 45 massive galaxy clusters. We use a combination of 1.4 and 30 GHz data to select a total of 28 probable cluster-member radio galaxies and also to predict their 140 GHz flux densities. All of these galaxies are steep-spectrum radio sources and they are found preferentially in the cool-core clusters within our sample. In particular, 11 of the 12 brightest cluster-member radio sources are associated with cool-core systems. Although none of the individual galaxies are robustly detected in the Bolocam data, the ensemble-average flux density at 140 GHz is consistent with, but slightly lower than, the extrapolation from lower frequencies assuming a constant spectral index. In addition, our data indicate an intrinsic scatter of {approx_equal} 30% around the power-law extrapolated flux densities at 140 GHz, although our data do not tightly constrain this scatter. For our cluster sample, which is composed of high-mass and moderate-redshift systems, we find that the maximum fractional change in the Sunyaev-Zel'dovich signal integrated over any single cluster due to the presence of these radio sources is {approx_equal} 20%, and only {approx_equal} 1/4 of themore » clusters show a fractional change of more than 1%. The amount of contamination is strongly dependent on cluster morphology, and nearly all of the clusters with {>=}1% contamination are cool-core systems. This result indicates that radio contamination is not significant compared with current noise levels in 140 GHz images of massive clusters and is in good agreement with the level of radio contamination found in previous results based on lower frequency data or simulations.« less

Authors:
; ; ; ; ; ;  [1];  [2]; ; ;  [3]; ; ;  [4];  [5]
  1. Division of Physics, Math, and Astronomy, California Institute of Technology, Pasadena, CA 91125 (United States)
  2. Kavli Institute for Cosmological Physics, University of Chicago, 5640 South Ellis Avenue, Chicago, IL 60637 (United States)
  3. Department of Physics and Astronomy, University of Southern California, Los Angeles, CA 90089 (United States)
  4. Institute of Astronomy and Astrophysics, Academia Sinica, P.O. Box 23-141, Taipei 10617, Taiwan (China)
  5. LeCosPA Center, National Taiwan University, Taipei 10617, Taiwan (China)
Publication Date:
OSTI Identifier:
22167732
Resource Type:
Journal Article
Journal Name:
Astrophysical Journal
Additional Journal Information:
Journal Volume: 764; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0004-637X
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ASTRONOMY; ASTROPHYSICS; COMPARATIVE EVALUATIONS; COMPUTERIZED SIMULATION; EMISSION SPECTRA; EXTRAPOLATION; FLUX DENSITY; GALAXY CLUSTERS; GHZ RANGE; IMAGES; INDEXES; MASS; MORPHOLOGY; NOISE; RADIO GALAXIES; RED SHIFT

Citation Formats

Sayers, J., Mroczkowski, T., Czakon, N. G., Golwala, S. R., Downes, T. P., Muchovej, S. J. C., Siegel, S., Mantz, A., Ameglio, S., Pierpaoli, E., Shitanishi, J. A., Koch, P. M., Lin, K. -Y., Umetsu, K., Molnar, S. M., and Moustakas, L., E-mail: jack@caltech.edu. THE CONTRIBUTION OF RADIO GALAXY CONTAMINATION TO MEASUREMENTS OF THE SUNYAEV-ZEL'DOVICH DECREMENT IN MASSIVE GALAXY CLUSTERS AT 140 GHz WITH BOLOCAM. United States: N. p., 2013. Web. doi:10.1088/0004-637X/764/2/152.
Sayers, J., Mroczkowski, T., Czakon, N. G., Golwala, S. R., Downes, T. P., Muchovej, S. J. C., Siegel, S., Mantz, A., Ameglio, S., Pierpaoli, E., Shitanishi, J. A., Koch, P. M., Lin, K. -Y., Umetsu, K., Molnar, S. M., & Moustakas, L., E-mail: jack@caltech.edu. THE CONTRIBUTION OF RADIO GALAXY CONTAMINATION TO MEASUREMENTS OF THE SUNYAEV-ZEL'DOVICH DECREMENT IN MASSIVE GALAXY CLUSTERS AT 140 GHz WITH BOLOCAM. United States. doi:10.1088/0004-637X/764/2/152.
Sayers, J., Mroczkowski, T., Czakon, N. G., Golwala, S. R., Downes, T. P., Muchovej, S. J. C., Siegel, S., Mantz, A., Ameglio, S., Pierpaoli, E., Shitanishi, J. A., Koch, P. M., Lin, K. -Y., Umetsu, K., Molnar, S. M., and Moustakas, L., E-mail: jack@caltech.edu. Wed . "THE CONTRIBUTION OF RADIO GALAXY CONTAMINATION TO MEASUREMENTS OF THE SUNYAEV-ZEL'DOVICH DECREMENT IN MASSIVE GALAXY CLUSTERS AT 140 GHz WITH BOLOCAM". United States. doi:10.1088/0004-637X/764/2/152.
@article{osti_22167732,
title = {THE CONTRIBUTION OF RADIO GALAXY CONTAMINATION TO MEASUREMENTS OF THE SUNYAEV-ZEL'DOVICH DECREMENT IN MASSIVE GALAXY CLUSTERS AT 140 GHz WITH BOLOCAM},
author = {Sayers, J. and Mroczkowski, T. and Czakon, N. G. and Golwala, S. R. and Downes, T. P. and Muchovej, S. J. C. and Siegel, S. and Mantz, A. and Ameglio, S. and Pierpaoli, E. and Shitanishi, J. A. and Koch, P. M. and Lin, K. -Y. and Umetsu, K. and Molnar, S. M. and Moustakas, L., E-mail: jack@caltech.edu},
abstractNote = {We describe in detail our characterization of the compact radio source population in 140 GHz Bolocam observations of a set of 45 massive galaxy clusters. We use a combination of 1.4 and 30 GHz data to select a total of 28 probable cluster-member radio galaxies and also to predict their 140 GHz flux densities. All of these galaxies are steep-spectrum radio sources and they are found preferentially in the cool-core clusters within our sample. In particular, 11 of the 12 brightest cluster-member radio sources are associated with cool-core systems. Although none of the individual galaxies are robustly detected in the Bolocam data, the ensemble-average flux density at 140 GHz is consistent with, but slightly lower than, the extrapolation from lower frequencies assuming a constant spectral index. In addition, our data indicate an intrinsic scatter of {approx_equal} 30% around the power-law extrapolated flux densities at 140 GHz, although our data do not tightly constrain this scatter. For our cluster sample, which is composed of high-mass and moderate-redshift systems, we find that the maximum fractional change in the Sunyaev-Zel'dovich signal integrated over any single cluster due to the presence of these radio sources is {approx_equal} 20%, and only {approx_equal} 1/4 of the clusters show a fractional change of more than 1%. The amount of contamination is strongly dependent on cluster morphology, and nearly all of the clusters with {>=}1% contamination are cool-core systems. This result indicates that radio contamination is not significant compared with current noise levels in 140 GHz images of massive clusters and is in good agreement with the level of radio contamination found in previous results based on lower frequency data or simulations.},
doi = {10.1088/0004-637X/764/2/152},
journal = {Astrophysical Journal},
issn = {0004-637X},
number = 2,
volume = 764,
place = {United States},
year = {2013},
month = {2}
}