@article{f4e5809b1dd443d8be648f834d78f8d9,
title = "The NANOGrav 12.5 yr data set: Polarimetry and Faraday rotation measures from observations of millisecond pulsars with the Green Bank Telescope",
abstract = "In this work, we present polarization profiles for 23 millisecond pulsars observed at 820 and 1500 MHz with the Green Bank Telescope as part of the NANOGrav pulsar timing array. We calibrate the data using Mueller matrix solutions calculated from observations of PSRs B1929+10 and J1022+1001. We discuss the polarization profiles, which can be used to constrain pulsar emission geometry, and present both the first published radio polarization profiles for nine pulsars and the discovery of very low-intensity average profile components ({"}microcomponents{"}) in four pulsars. We obtain the Faraday rotation measures for each pulsar and use them to calculate the Galactic magnetic field parallel to the line of sight for different lines of sight through the interstellar medium. We fit for linear and sinusoidal trends in time in the dispersion measure and Galactic magnetic field and detect magnetic field variations with a period of 1 yr in some pulsars, but overall find that the variations in these parameters are more consistent with a stochastic origin. An erratum has been published for this article: https://iopscience.iop.org/article/10.3847/1538-4357/acab5f",
author = "Wahl, {H. M.} and McLaughlin, {M. A.} and Gentile, {P. A.} and Jones, {M. L.} and R. Spiewak and Z. Arzoumanian and K. Crowter and Demorest, {P. B.} and Decesar, {M. E.} and T. Dolch and Ellis, {J. A.} and Ferdman, {R. D.} and Ferrara, {E. C.} and E. Fonseca and N. Garver-Daniels and G. Jones and Lam, {M. T.} and L. Levin and N. Lewandowska and Lorimer, {D. R.} and Lynch, {R. S.} and Madison, {D. R.} and C. Ng and Nice, {D. J.} and Pennucci, {T. T.} and Ransom, {S. M.} and P. Ray and Stairs, {I. H.} and K. Stovall and Swiggum, {J. K.} and Zhu, {W. W.}",
note = "An erratum has been published for this article: Erratum: {"}The NANOGrav 12.5 yr Data Set: Polarimetry and Faraday Rotation Measures from Observations of Millisecond Pulsars with the Green Bank Telescope{"} (2022, ApJ, 926, 168) H. M. Wahl, M. A. McLaughlin, P. A. Gentile, M. L. Jones, R. Spiewak, Z. Arzoumanian, K. Crowter, P. B. Demorest, M. E. DeCesar, T. Dolch et al. The Astrophysical Journal, Volume 941, Number 2. DOI 10.3847/1538-4357/acab5f. Published 2022 December 27. Acknowledgements: We thank the double pulsar team members who are not authors on this paper (M. Kramer, N. Pol, A. Possenti, and P. Freire) for their B1929+10 data. We also thank Dr. James McKee for useful conversations regarding this work, and the anonymous referee for the very helpful comments and suggestions. Funding: This research was made possible by NASA West Virginia Space Grant Consortium, NASA Agreement #80NSSC20M0055. This work was also supported by NSF Award OIA-1458952. The Green Bank Observatory is a facility of the NSF operated under cooperative agreement by Associated Universities, Inc. The NANOGrav project receives support from National Science Foundation (NSF) Physics Frontiers Center award Nos. 1430284 and 2020265. Work on NANOGrav at NRL is supported by ONR 6.1 basic research funding. T.D. and M.L. acknowledge NSF AAG award No. 2009468. K.C. is supported by a UBC Four Year Fellowship (6456). E.C.F. is supported by NASA under award number 80GSFC17M0002. M.A.M. is also supported by NSF award number 1517003. ",
year = "2022",
month = feb,
day = "22",
doi = "10.3847/1538-4357/ac4045",
language = "English",
volume = "926",
journal = "Astrophysical Journal",
issn = "0004-637X",
publisher = "IOP Publishing Ltd",
number = "2",
}