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Title: THE NANOGRAV NINE-YEAR DATA SET: OBSERVATIONS, ARRIVAL TIME MEASUREMENTS, AND ANALYSIS OF 37 MILLISECOND PULSARS

We present high-precision timing observations spanning up to nine years for 37 millisecond pulsars monitored with the Green Bank and Arecibo radio telescopes as part of the North American Nanohertz Observatory for Gravitational Waves (NANOGrav) project. We describe the observational and instrumental setups used to collect the data, and methodology applied for calculating pulse times of arrival; these include novel methods for measuring instrumental offsets and characterizing low signal-to-noise ratio timing results. The time of arrival data are fit to a physical timing model for each source, including terms that characterize time-variable dispersion measure and frequency-dependent pulse shape evolution. In conjunction with the timing model fit, we have performed a Bayesian analysis of a parameterized timing noise model for each source, and detect evidence for excess low-frequency, or “red,” timing noise in 10 of the pulsars. For 5 of these cases this is likely due to interstellar medium propagation effects rather than intrisic spin variations. Subsequent papers in this series will present further analysis of this data set aimed at detecting or limiting the presence of nanohertz-frequency gravitational wave signals.
Authors:
 [1] ; ; ; ;  [2] ; ;  [3] ;  [4] ;  [5] ;  [6] ; ; ;  [7] ;  [8] ; ;  [9] ; ;  [10] ;  [11] ;  [12] more »; ; « less
  1. Center for Research and Exploration in Space Science and Technology and X-Ray Astrophysics Laboratory, NASA Goddard Space Flight Center, Code 662, Greenbelt, MD 20771 (United States)
  2. Department of Astronomy, Cornell University, Ithaca, NY 14853 (United States)
  3. National Radio Astronomy Observatory, P.O. Box O, Socorro, NM 87801 (United States)
  4. Center for Gravitation, Cosmology and Astrophysics, Department of Physics, University of Wisconsin-Milwaukee, P.O. Box 413, Milwaukee, WI 53201 (United States)
  5. Department of Physics and Astronomy, Franklin and Marshall College, P.O. Box 3003, Lancaster, PA 17604 (United States)
  6. Department of Physics, Montana State University, Bozeman, MT 59717 (United States)
  7. Department of Physics and Astronomy, University of British Columbia, 6224 Agricultural Road, Vancouver, BC V6T 1Z1 (Canada)
  8. Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Dr. Pasadena CA 91109 (United States)
  9. Department of Physics, McGill University, 3600 rue Universite, Montreal, QC H3A 2T8 (Canada)
  10. Department of Physics, West Virginia University, P.O. Box 6315, Morgantown, WV 26505 (United States)
  11. Center for Gravitational Wave Astronomy, University of Texas at Brownsville, Brownsville, TX 78520 (United States)
  12. Department of Physics, Columbia University, 550 W. 120th St. New York, NY 10027 (United States)
Publication Date:
OSTI Identifier:
22518719
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 813; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ACCURACY; DATA ANALYSIS; FREQUENCY DEPENDENCE; GRAVITATIONAL WAVES; NOISE; PULSARS; RADIO TELESCOPES; SIGNAL-TO-NOISE RATIO; SPIN; TIME MEASUREMENT; VARIATIONS