Observations of 4U 1626–67 with the Imaging X-Ray Polarimetry Explorer-Reference-Cited by-同舟云学术

Observations of 4U 1626–67 with the Imaging X-Ray Polarimetry Explorer

Published:2022-11-01 Issue:1 Volume:940 Page:70
ISSN:0004-637X
Container-title:The Astrophysical Journal
language:
Short-container-title:ApJ

Author:

Marshall Herman L.^ORCID,Ng Mason^ORCID,Rogantini Daniele^ORCID,Heyl Jeremy^ORCID,Tsygankov Sergey S.^ORCID,Poutanen Juri^ORCID,Costa Enrico^ORCID,Zane Silvia^ORCID,Malacaria Christian^ORCID,Agudo Iván^ORCID,Antonelli Lucio A.^ORCID,Bachetti Matteo^ORCID,Baldini Luca^ORCID,Baumgartner Wayne H.^ORCID,Bellazzini Ronaldo^ORCID,Bianchi Stefano^ORCID,Bongiorno Stephen D.^ORCID,Bonino Raffaella^ORCID,Brez Alessandro^ORCID,Bucciantini Niccolò^ORCID,Capitanio Fiamma^ORCID,Castellano Simone^ORCID,Cavazzuti Elisabetta^ORCID,Ciprini Stefano^ORCID,De Rosa Alessandra^ORCID,Monte Ettore Del^ORCID,Gesu Laura Di^ORCID,Lalla Niccolò Di^ORCID,Marco Alessandro Di^ORCID,Donnarumma Immacolata^ORCID,Doroshenko Victor^ORCID,Dovčiak Michal^ORCID,Ehlert Steven R.^ORCID,Enoto Teruaki^ORCID,Evangelista Yuri^ORCID,Fabiani Sergio^ORCID,Ferrazzoli Riccardo^ORCID,Garcia Javier A.^ORCID,Gunji Shuichi^ORCID,Hayashida Kiyoshi,Iwakiri Wataru^ORCID,Jorstad Svetlana G.^ORCID,Karas Vladimir^ORCID,Kitaguchi Takao,Kolodziejczak Jeffery J.^ORCID,Krawczynski Henric^ORCID,Monaca Fabio La^ORCID,Latronico Luca^ORCID,Liodakis Ioannis^ORCID,Maldera Simone^ORCID,Manfreda Alberto^ORCID,Marin Frédéric^ORCID,Marinucci Andrea^ORCID,Marscher Alan P.^ORCID,Matt Giorgio^ORCID,Mitsuishi Ikuyuki,Mizuno Tsunefumi^ORCID,Muleri Fabio^ORCID,Ng C.-Y.^ORCID,O’Dell Stephen L.^ORCID,Omodei Nicola^ORCID,Oppedisano Chiara^ORCID,Papitto Alessandro^ORCID,Pavlov George G.^ORCID,Peirson Abel L.^ORCID,Perri Matteo^ORCID,Pesce-Rollins Melissa^ORCID,Petrucci Pierre-Olivier^ORCID,Pilia Maura^ORCID,Possenti Andrea^ORCID,Puccetti Simonetta^ORCID,Ramsey Brian D.^ORCID,Rankin John^ORCID,Ratheesh Ajay^ORCID,Romani Roger W.^ORCID,Sgrò Carmelo^ORCID,Slane Patrick^ORCID,Soffitta Paolo^ORCID,Spandre Gloria^ORCID,Tamagawa Toru^ORCID,Tavecchio Fabrizio^ORCID,Taverna Roberto^ORCID,Tawara Yuzuru,Tennant Allyn F.^ORCID,Thomas Nicholas E.^ORCID,Tombesi Francesco^ORCID,Trois Alessio^ORCID,Turolla Roberto^ORCID,Vink Jacco^ORCID,Weisskopf Martin C.^ORCID,Wu Kinwah^ORCID,Xie Fei^ORCID,Schulz Norbert S.^ORCID,Chakrabarty Deepto^ORCID

Abstract

Abstract We present measurements of the polarization of X-rays in the 2–8 keV band from the pulsar in the ultracompact low-mass X-ray binary 4U 1626–67 using data from the Imaging X-Ray Polarimetry Explorer (IXPE). The 7.66 s pulsations were clearly detected throughout the IXPE observations as well as in the NICER soft X-ray observations, which we used as the basis for our timing analysis and to constrain the spectral shape over the 0.4–10 keV energy band. Chandra HETGS high-resolution X-ray spectra were also obtained near the times of the IXPE observations for firm spectral modeling. We found an upper limit on the pulse-averaged linear polarization of <4% (at 95% confidence). Similarly, there was no significant detection of polarized flux in pulse phase intervals when subdividing the bandpass by energy. However, spectropolarimetric modeling over the full bandpass in pulse phase intervals provided a marginal detection of polarization of the power-law spectral component at the 4.8% ± 2.3% level (90% confidence). We discuss the implications concerning the accretion geometry onto the pulsar, favoring two-component models of the pulsed emission.

Funder

NASA ∣ Marshall Space Flight Center

NASA ∣ NASA Headquarters

SI ∣ Smithsonian Astrophysical Observatory

NASA ∣ Goddard Space Flight Center

Agenzia Spaziale Italiana

Russian Science Foundation

Academy of Finland

Publisher

American Astronomical Society

Subject

Space and Planetary Science,Astronomy and Astrophysics