The Astrophysical Journal (Jan 2025)
Pulse Profile Variability of PSR J1022+1001 in NANOGrav Data
- William Fiore,
- Maura A. McLaughlin,
- Gabriella Agazie,
- Akash Anumarlapudi,
- Anne M. Archibald,
- Zaven Arzoumanian,
- Paul T. Baker,
- Paul R. Brook,
- H. Thankful Cromartie,
- Kathryn Crowter,
- Megan E. DeCesar,
- Paul B. Demorest,
- Lankeswar Dey,
- Timothy Dolch,
- Elizabeth C. Ferrara,
- Emmanuel Fonseca,
- Gabriel E. Freedman,
- Nate Garver-Daniels,
- Peter A. Gentile,
- Joseph Glaser,
- Deborah C. Good,
- Jeffrey S. Hazboun,
- Ross J. Jennings,
- Megan L. Jones,
- David L. Kaplan,
- Matthew Kerr,
- Michael T. Lam,
- Duncan R. Lorimer,
- Jing Luo,
- Ryan S. Lynch,
- Alexander McEwen,
- Natasha McMann,
- Bradley W. Meyers,
- Cherry Ng,
- David J. Nice,
- Timothy T. Pennucci,
- Benetge B. P. Perera,
- Nihan S. Pol,
- Henri A. Radovan,
- Scott M. Ransom,
- Paul S. Ray,
- Ann Schmiedekamp,
- Carl Schmiedekamp,
- Brent J. Shapiro-Albert,
- Ingrid H. Stairs,
- Kevin Stovall,
- Abhimanyu Susobhanan,
- Joseph K. Swiggum,
- Haley M. Wahl
Affiliations
- William Fiore
- ORCiD
- Department of Physics and Astronomy, University of British Columbia , 6224 Agricultural Road, Vancouver, BC V6T 1Z1, Canada ; [email protected]; Department of Physics and Astronomy, West Virginia University , P.O. Box 6315, Morgantown, WV 26506, USA; Center for Gravitational Waves and Cosmology, West Virginia University , Chestnut Ridge Research Building, Morgantown, WV 26505, USA
- Maura A. McLaughlin
- ORCiD
- Department of Physics and Astronomy, West Virginia University , P.O. Box 6315, Morgantown, WV 26506, USA; Center for Gravitational Waves and Cosmology, West Virginia University , Chestnut Ridge Research Building, Morgantown, WV 26505, USA
- Gabriella Agazie
- ORCiD
- Center for Gravitation, Cosmology and Astrophysics, Department of Physics, University of Wisconsin-Milwaukee , P.O. Box 413, Milwaukee, WI 53201, USA
- Akash Anumarlapudi
- ORCiD
- Center for Gravitation, Cosmology and Astrophysics, Department of Physics, University of Wisconsin-Milwaukee , P.O. Box 413, Milwaukee, WI 53201, USA
- Anne M. Archibald
- ORCiD
- Newcastle University , NE1 7RU, UK
- Zaven Arzoumanian
- ORCiD
- X-Ray Astrophysics Laboratory , NASA Goddard Space Flight Center, Code 662, Greenbelt, MD 20771, USA
- Paul T. Baker
- ORCiD
- Department of Physics and Astronomy, Widener University , One University Place, Chester, PA 19013, USA
- Paul R. Brook
- ORCiD
- Institute for Gravitational Wave Astronomy and School of Physics and Astronomy, University of Birmingham , Edgbaston, Birmingham B15 2TT, UK
- H. Thankful Cromartie
- ORCiD
- National Research Council Research Associate , National Academy of Sciences, Washington, DC 20001, USA
- Kathryn Crowter
- ORCiD
- Department of Physics and Astronomy, University of British Columbia , 6224 Agricultural Road, Vancouver, BC V6T 1Z1, Canada ; [email protected]
- Megan E. DeCesar
- ORCiD
- George Mason University , Fairfax, VA 22030, USA
- Paul B. Demorest
- ORCiD
- National Radio Astronomy Observatory , 1003 Lopezville Road, Socorro, NM 87801, USA
- Lankeswar Dey
- ORCiD
- Department of Physics and Astronomy, West Virginia University , P.O. Box 6315, Morgantown, WV 26506, USA; Center for Gravitational Waves and Cosmology, West Virginia University , Chestnut Ridge Research Building, Morgantown, WV 26505, USA
- Timothy Dolch
- ORCiD
- Department of Physics, Hillsdale College , 33 E. College Street, Hillsdale, MI 49242, USA; Eureka Scientific , 2452 Delmer Street, Suite 100, Oakland, CA 94602-3017, USA
- Elizabeth C. Ferrara
- ORCiD
- Department of Astronomy, University of Maryland , College Park, MD 20742, USA; Center for Research and Exploration in Space Science and Technology , NASA/GSFC, Greenbelt, MD 20771, USA; NASA Goddard Space Flight Center , Greenbelt, MD 20771, USA
- Emmanuel Fonseca
- ORCiD
- Department of Physics and Astronomy, West Virginia University , P.O. Box 6315, Morgantown, WV 26506, USA; Center for Gravitational Waves and Cosmology, West Virginia University , Chestnut Ridge Research Building, Morgantown, WV 26505, USA
- Gabriel E. Freedman
- ORCiD
- Center for Gravitation, Cosmology and Astrophysics, Department of Physics, University of Wisconsin-Milwaukee , P.O. Box 413, Milwaukee, WI 53201, USA
- Nate Garver-Daniels
- ORCiD
- Department of Physics and Astronomy, West Virginia University , P.O. Box 6315, Morgantown, WV 26506, USA; Center for Gravitational Waves and Cosmology, West Virginia University , Chestnut Ridge Research Building, Morgantown, WV 26505, USA
- Peter A. Gentile
- ORCiD
- Department of Physics and Astronomy, West Virginia University , P.O. Box 6315, Morgantown, WV 26506, USA; Center for Gravitational Waves and Cosmology, West Virginia University , Chestnut Ridge Research Building, Morgantown, WV 26505, USA
- Joseph Glaser
- ORCiD
- Department of Physics and Astronomy, West Virginia University , P.O. Box 6315, Morgantown, WV 26506, USA; Center for Gravitational Waves and Cosmology, West Virginia University , Chestnut Ridge Research Building, Morgantown, WV 26505, USA
- Deborah C. Good
- ORCiD
- Department of Physics and Astronomy, University of Montana , 32 Campus Drive, Missoula, MT 59812, USA
- Jeffrey S. Hazboun
- ORCiD
- Department of Physics, Oregon State University , Corvallis, OR 97331, USA
- Ross J. Jennings
- ORCiD
- Department of Physics and Astronomy, West Virginia University , P.O. Box 6315, Morgantown, WV 26506, USA; Center for Gravitational Waves and Cosmology, West Virginia University , Chestnut Ridge Research Building, Morgantown, WV 26505, USA
- Megan L. Jones
- ORCiD
- Center for Gravitation, Cosmology and Astrophysics, Department of Physics, University of Wisconsin-Milwaukee , P.O. Box 413, Milwaukee, WI 53201, USA
- David L. Kaplan
- ORCiD
- Center for Gravitation, Cosmology and Astrophysics, Department of Physics, University of Wisconsin-Milwaukee , P.O. Box 413, Milwaukee, WI 53201, USA
- Matthew Kerr
- ORCiD
- Space Science Division , Naval Research Laboratory, Washington, DC 20375-5352, USA
- Michael T. Lam
- ORCiD
- SETI Institute , 339 N Bernardo Avenue Suite 200, Mountain View, CA 94043, USA; School of Physics and Astronomy, Rochester Institute of Technology , Rochester, NY 14623, USA; Laboratory for Multiwavelength Astrophysics, Rochester Institute of Technology , Rochester, NY 14623, USA
- Duncan R. Lorimer
- ORCiD
- Department of Physics and Astronomy, West Virginia University , P.O. Box 6315, Morgantown, WV 26506, USA; Center for Gravitational Waves and Cosmology, West Virginia University , Chestnut Ridge Research Building, Morgantown, WV 26505, USA
- Jing Luo
- ORCiD
- Department of Astronomy & Astrophysics, University of Toronto , 50 Saint George Street, Toronto, ON M5S 3H4, Canada
- Ryan S. Lynch
- ORCiD
- Green Bank Observatory , P.O. Box 2, Green Bank, WV 24944, USA
- Alexander McEwen
- ORCiD
- Center for Gravitation, Cosmology and Astrophysics, Department of Physics, University of Wisconsin-Milwaukee , P.O. Box 413, Milwaukee, WI 53201, USA
- Natasha McMann
- ORCiD
- Department of Physics and Astronomy, Vanderbilt University , 2301 Vanderbilt Place, Nashville, TN 37235, USA
- Bradley W. Meyers
- ORCiD
- Department of Physics and Astronomy, University of British Columbia , 6224 Agricultural Road, Vancouver, BC V6T 1Z1, Canada ; [email protected]; International Centre for Radio Astronomy Research, Curtin University , Bentley, WA 6102, Australia
- Cherry Ng
- ORCiD
- Dunlap Institute for Astronomy and Astrophysics, University of Toronto , 50 St. George Street, Toronto, ON M5S 3H4, Canada
- David J. Nice
- ORCiD
- Department of Physics, Lafayette College , Easton, PA 18042, USA
- Timothy T. Pennucci
- ORCiD
- Institute of Physics and Astronomy, Eötvös Loránd University , Pázmány P. s. 1/A, 1117 Budapest, Hungary
- Benetge B. P. Perera
- ORCiD
- Arecibo Observatory , HC3 Box 53995, Arecibo, PR 00612, USA
- Nihan S. Pol
- ORCiD
- Department of Physics and Astronomy, Vanderbilt University , 2301 Vanderbilt Place, Nashville, TN 37235, USA
- Henri A. Radovan
- ORCiD
- Department of Physics, University of Puerto Rico , Mayagüez, PR 00681, USA
- Scott M. Ransom
- ORCiD
- National Radio Astronomy Observatory , 520 Edgemont Road, Charlottesville, VA 22903, USA
- Paul S. Ray
- ORCiD
- Space Science Division , Naval Research Laboratory, Washington, DC 20375-5352, USA
- Ann Schmiedekamp
- ORCiD
- Department of Physics, Penn State Abington , Abington, PA 19001, USA
- Carl Schmiedekamp
- ORCiD
- Department of Physics, Penn State Abington , Abington, PA 19001, USA
- Brent J. Shapiro-Albert
- ORCiD
- Department of Physics and Astronomy, West Virginia University , P.O. Box 6315, Morgantown, WV 26506, USA; Center for Gravitational Waves and Cosmology, West Virginia University , Chestnut Ridge Research Building, Morgantown, WV 26505, USA; Giant Army , 915A 17th Avenue, Seattle, WA 98122, USA
- Ingrid H. Stairs
- ORCiD
- Department of Physics and Astronomy, University of British Columbia , 6224 Agricultural Road, Vancouver, BC V6T 1Z1, Canada ; [email protected]
- Kevin Stovall
- ORCiD
- National Radio Astronomy Observatory , 1003 Lopezville Road, Socorro, NM 87801, USA
- Abhimanyu Susobhanan
- ORCiD
- Max-Planck-Institut für Gravitationsphysik (Albert-Einstein-Institut) , Callinstrasse 38, D-30167, Hannover, Germany
- Joseph K. Swiggum
- ORCiD
- Department of Physics, Lafayette College , Easton, PA 18042, USA
- Haley M. Wahl
- ORCiD
- Department of Physics and Astronomy, West Virginia University , P.O. Box 6315, Morgantown, WV 26506, USA; Center for Gravitational Waves and Cosmology, West Virginia University , Chestnut Ridge Research Building, Morgantown, WV 26505, USA
- DOI
- https://doi.org/10.3847/1538-4357/adc255
- Journal volume & issue
-
Vol. 984,
no. 2
p. 139
Abstract
Pulse profile stability is a central assumption of standard pulsar timing methods. Thus, it is important for pulsar timing array experiments such as the North American Nanohertz Observatory for Gravitational Waves (NANOGrav) to account for any pulse profile variability present in their data sets. We show that in the NANOGrav 15 yr data set, the integrated pulse profile of PSR J1022+1001 as seen by the Arecibo radio telescope at 430, 1380, and 2030 MHz varies considerably in its shape from observation to observation. We investigate the possibility that this is due to the “ideal feed assumption” (IFA), on which NANOGrav’s routine polarization calibration procedure relies. PSR J1022+1001 is ∼90% polarized in one pulse profile component, and also has significant levels of circular polarization. Time-dependent deviations in the feed’s polarimetric response (PR) could cause mixing between the intensity I and the other Stokes parameters, leading to the observed variability. We calibrate the PR using a mixture of measurement equation modeling and measurement equation template matching techniques. The resulting profiles are no less variable than those calibrated using the IFA method, nor do they provide an improvement in the timing quality of this pulsar. We observe the pulse shape in 25 MHz bandwidths to vary consistently across the band, which cannot be explained by interstellar scintillation in combination with profile evolution with frequency. Instead, we favor phenomena intrinsic to the pulsar as the cause.
Keywords
