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A pulsar-based timescale from the International Pulsar Timing Array

Hobbs, G. and Guo, L. and Caballero, R. N. and Coles, W. and Lee, K. J. and Manchester, R. N. and Reardon, D. J. and Matsakis, D. and Tong, M. L. and Arzoumanian, Z. and Bailes, M. and Bassa, C. G. and Bhat, N. D. R. and Brazier, A. and Burke-Spolaor, S. and Champion, D. J. and Chatterjee, S. and Cognard, I. and Dai, S. and Desvignes, G. and Dolch, T. and Ferdman, R. D. and Graikou, E. and Guillemot, L. and Janssen, G. H. and Keith, M. J. and Kerr, M. and Kramer, M. and Lam, M. T. and Liu, K. and Lyne, A. and Lazio, T. J. W. and Lynch, R. and McKee, J. W. and McLaughlin, M. A. and Mingarelli, C. M. F. and Nice, D. J. and Osłowski, S. and Pennucci, T. T. and Perera, B. B. P. and Perrodin, D. and Possenti, A. and Russell, C. J. and Sanidas, S. and Sesana, A. and Shaifullah, G. and Shannon, R. M. and Simon, J. and Spiewak, R. and Stairs, I. H. and Stappers, B. W. and Swiggum, J. K. and Taylor, S. R. and Theureau, G. and Toomey, L. and van Haasteren, R. and Wang, J. B. and Wang, Y. and Zhu, X. J. (2020) A pulsar-based timescale from the International Pulsar Timing Array. Monthly Notices of the Royal Astronomical Society, 491 (4). pp. 5951-5965. ISSN 0035-8711.

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We have constructed a new time-scale, TT(IPTA16), based on observations of radio pulsars presented in the first data release from the International Pulsar Timing Array (IPTA). We used two analysis techniques with independent estimates of the noise models for the pulsar observations and different algorithms for obtaining the pulsar time-scale. The two analyses agree within the estimated uncertainties and both agree with TT(BIPM17), a post-corrected time-scale produced by the Bureau International des Poids et Mesures (BIPM). We show that both methods could detect significant errors in TT(BIPM17) if they were present. We estimate the stability of the atomic clocks from which TT(BIPM17) is derived using observations of four rubidium fountain clocks at the US Naval Observatory. Comparing the power spectrum of TT(IPTA16) with that of these fountain clocks suggests that pulsar-based time-scales are unlikely to contribute to the stability of the best time-scales over the next decade, but they will remain a valuable independent check on atomic time-scales. We also find that the stability of the pulsar-based time-scale is likely to be limited by our knowledge of solar-system dynamics, and that errors in TT(BIPM17) will not be a limiting factor for the primary goal of the IPTA, which is to search for the signatures of nano-Hertz gravitational waves.

Item Type:Article
Related URLs:
URLURL TypeDescription
Hobbs, G.0000-0003-1502-100X
Reardon, D. J.0000-0002-2035-4688
Bailes, M.0000-0003-3294-3081
Burke-Spolaor, S.0000-0003-4052-7838
Chatterjee, S.0000-0002-2878-1502
Dolch, T.0000-0001-8885-6388
Ferdman, R. D.0000-0002-2223-1235
Kerr, M.0000-0002-0893-4073
Lam, M. T.0000-0003-0721-651X
Lazio, T. J. W.0000-0002-3873-5497
McLaughlin, M. A.0000-0001-7697-7422
Mingarelli, C. M. F.0000-0002-4307-1322
Nice, D. J.0000-0002-6709-2566
Osłowski, S.0000-0003-0289-0732
Pennucci, T. T.0000-0001-5465-2889
Perera, B. B. P.0000-0002-8509-5947
Shaifullah, G.0000-0002-8452-4834
Simon, J.0000-0003-1407-6607
Spiewak, R.0000-0002-6730-3298
Stairs, I. H.0000-0001-9784-8670
Swiggum, J. K.0000-0002-1075-3837
Taylor, S. R.0000-0003-0264-1453
van Haasteren, R.0000-0002-6428-2620
Wang, Y.0000-0001-8990-5700
Zhu, X. J.0000-0001-7049-6468
Additional Information:© 2019 The Author(s). Published by Oxford University Press on behalf of the Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model ( Accepted 2019 October 28. Received 2019 October 7; in original form 2019 January 15. Published: 04 November 2019. The National Radio Astronomy Observatory and Green Bank Observatories are facilities of the NSF operated under cooperative agreement by Associated Universities, Inc. The Arecibo Observatory is operated by SRI International under a cooperative agreement with the NSF (AST-1100968), and in alliance with Ana G. Méndez-Universidad Metropolitana, and the Universities Space Research Association. The Parkes telescope is part of the Australia Telescope which is funded by the Commonwealth Government for operation as a National Facility managed by CSIRO. The Westerbork Synthesis Radio Telescope is operated by the Netherlands Institute for Radio Astronomy (ASTRON) with support from The Netherlands Foundation for Scientific Research NWO. The 100-m Effelsberg Radio Telescope is operated by the Max-Planck-Institut für Radioastronomie at Effelsberg. Some of the work reported in this paper was supported by the ERC Advanced Grant ‘LEAP’, Grant Agreement Number 227947 (PI Kramer). Pulsar research at the Jodrell Bank Centre for Astrophysics is supported by a consolidated grant from STFC. The Nancay radio telescope is operated by the Paris Observatory, associated with the Centre National de la Recherche Scientifique (CNRS) and acknowledges financial support from the ‘Programme National de Cosmologie et Galaxies (PNCG)’ and ‘Gravitation, Références, Astronomie, Métrologie (GRAM)’ programmes of CNRS/INSU, France. LG is supported by National Natural Science Foundation of China No.11873076. The Flatiron Institute is supported by the Simons Foundation. The NANOGrav work in this paper was supported by National Science Foundation (NSF) PIRE program award number 0968296 and NSF Physics Frontiers Center award number 1430824. KJL is supported by XDB23010200, National Basic Research Program of China, 973 Program, 2015CB857101, and NSFC U15311243, 11690024, and the MPG funding for the Max-Planck Partner Group. LG was supported by National Natural Science Foundation of China (NSFC) (nos. U1431117) and #11010250. EG acknowledges the support from IMPRS Bonn/Cologne and the Bonn–Cologne Graduate School (BCGS). YW acknowledges the support from NSFC under grants 11503007, 91636111, and 11690021. SBS acknowledges the support of NSF EPSCoR award number 1458952. KL and GD acknowledge the financial support by the European Research Council for the ERC Synergy Grant BlackHoleCam under contract no. 610058. Part of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. Work at NRL is supported by NASA. We thank Patrizia Tavella from the BIPM for helping us understand the nomenclature used when describing time standards.
Funding AgencyGrant Number
Ana G. Méndez-Universidad MetropolitanaUNSPECIFIED
Universities Space Research AssociationUNSPECIFIED
Commonwealth of AustraliaUNSPECIFIED
Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO)UNSPECIFIED
European Research Council (ERC)227947
Science and Technology Facilities Council (STFC)UNSPECIFIED
Centre National de la Recherche Scientifique (CNRS)UNSPECIFIED
Programme National de Cosmologie et Galaxies (PNCG)UNSPECIFIED
Gravitation, Références, Astronomie, Métrologie (GRAM)UNSPECIFIED
Institut National des Sciences de l'Univers (INSU)UNSPECIFIED
National Natural Science Foundation of China11873076
Simons FoundationUNSPECIFIED
National Natural Science Foundation of ChinaXDB23010200
National Basic Research Program of China 973 Program2015CB857101
National Natural Science Foundation of ChinaU15311243
National Natural Science Foundation of China11690024
Max-Planck GesellschaftUNSPECIFIED
National Natural Science Foundation of ChinaU1431117
National Natural Science Foundation of China11010250
International Max Planck Research School (IMPRS) for Astronomy and AstrophysicsUNSPECIFIED
Bonn-Cologne Graduate School of Physics and AstronomyUNSPECIFIED
National Natural Science Foundation of China11503007
National Natural Science Foundation of China91636111
National Natural Science Foundation of China11690021
European Research Council (ERC)610058
Subject Keywords:time – pulsars: general
Issue or Number:4
Record Number:CaltechAUTHORS:20200302-131001361
Persistent URL:
Official Citation:G Hobbs, L Guo, R N Caballero, W Coles, K J Lee, R N Manchester, D J Reardon, D Matsakis, M L Tong, Z Arzoumanian, M Bailes, C G Bassa, N D R Bhat, A Brazier, S Burke-Spolaor, D J Champion, S Chatterjee, I Cognard, S Dai, G Desvignes, T Dolch, R D Ferdman, E Graikou, L Guillemot, G H Janssen, M J Keith, M Kerr, M Kramer, M T Lam, K Liu, A Lyne, T J W Lazio, R Lynch, J W McKee, M A McLaughlin, C M F Mingarelli, D J Nice, S Osłowski, T T Pennucci, B B P Perera, D Perrodin, A Possenti, C J Russell, S Sanidas, A Sesana, G Shaifullah, R M Shannon, J Simon, R Spiewak, I H Stairs, B W Stappers, J K Swiggum, S R Taylor, G Theureau, L Toomey, R van Haasteren, J B Wang, Y Wang, X J Zhu, A pulsar-based time-scale from the International Pulsar Timing Array, Monthly Notices of the Royal Astronomical Society, Volume 491, Issue 4, February 2020, Pages 5951–5965,
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:101653
Deposited By: Tony Diaz
Deposited On:02 Mar 2020 21:36
Last Modified:02 Mar 2020 21:36

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