X-ray polarimetry and spectroscopy of the neutron star low-mass X-ray binary GX 9+9: an in-depth study with IXPE and NuSTAR
| dc.contributor.author | Ursini, F. | |
| dc.contributor.author | Farinelli, R. | |
| dc.contributor.author | Gnarini, A. | |
| dc.contributor.author | Poutanen, J. | |
| dc.contributor.author | Negro, Michela | |
| dc.contributor.author | et al. | |
| dc.date.accessioned | 2023-06-27T20:33:32Z | |
| dc.date.available | 2023-06-27T20:33:32Z | |
| dc.date.issued | 2023-06-05 | |
| dc.description | Authors: S. Bianchi, F. Capitanio, A. Di Marco, S. Fabiani, F. La Monaca, C. Malacaria, G. Matt, R. Mikušincová, M. Cocchi, P. Kaaret, J. J. E. Kajava, M. Pilia, W. Zhang, I. Agudo, L. A. Antonelli, M. Bachetti, L. Baldini, W. H. Baumgartner, R. Bellazzini, S. D. Bongiorno, R. Bonino, A. Brez, N. Bucciantini, S. Castellano, E. Cavazzuti, C.-T. Chen, S. Ciprini, E. Costa, A. De Rosa, E. Del Monte, L. Di Gesu, N. Di Lalla, I. Donnarumma, V. Doroshenko, M. Dovčiak, S. R. Ehlert, T. Enoto, Y. Evangelista, R. Ferrazzoli, J. A. Garcia, S. Gunji, K. Hayashida, J. Heyl, W. Iwakiri, S. G. Jorstad, V. Karas, F. Kislat, T. Kitaguchi, J. J. Kolodziejczak, H. Krawczynski, L. Latronico, I. Liodakis, S. Maldera, A. Manfreda, F. Marin, A. Marinucci, A. P. Marscher, H. L. Marshall, F. Massaro, I. Mitsuishi, T. Mizuno, F. Muleri, C.-Y. Ng, S. L. O’Dell, N. Omodei, C. Oppedisano, A. Papitto, G. G. Pavlov, A. L. Peirson, M. Perri, M. Pesce-Rollins, P.-O. Petrucci, M. Pilia, A. Possenti, S. Puccetti, B. D. Ramsey, J. Rankin, A. Ratheesh, O. J. Roberts, R. W. Romani, C. Sgrò, P. Slane, P. Soffitta, G. Spandre, D. A. Swartz, T. Tamagawa, F. Tavecchio, R. Taverna, Y. Tawara, A. F. Tennant, N. E. Thomas, F. Tombesi, A. Trois, S. S. Tsygankov, R. Turolla, J. Vink, M. C. Weisskopf, K. Wu, F. Xie, and S. Zane | en_US |
| dc.description.abstract | We report on a comprehensive analysis of simultaneous X-ray polarimetric and spectral data of the bright atoll source GX 9+9 with the Imaging X-ray Polarimetry Explorer (IXPE) and NuSTAR. The source is significantly polarized in the 4--8 keV band, with a degree of 2.2% ± 0.5% (uncertainty at the 68% confidence level). The NuSTAR broad-band spectrum clearly shows an iron line, and is well described by a model including thermal disk emission, a Comptonized component, and reflection. From a spectro-polarimetric fit, we obtain an upper limit to the polarization degree of the disk of 4% (at 99% confidence level), while the contribution of Comptonized and reflected radiation cannot be conclusively separated. However, the polarization is consistent with resulting from a combination of Comptonization in a boundary or spreading layer, plus reflection off the disc, which gives a significant contribution in any realistic scenario. | en_US |
| dc.description.sponsorship | We thank the anonymous referee for carefully reading the paper and for useful comments that improved the manuscript. The Imaging Xray Polarimetry Explorer (IXPE) is a joint US and Italian mission. The US contribution is supported by the National Aeronautics and Space Administration (NASA) and led and managed by its Marshall Space Flight Center (MSFC), with industry partner Ball Aerospace (contract NNM15AA18C). The Italian contribution is supported by the Italian Space Agency (Agenzia Spaziale Italiana, ASI) through contract ASI-OHBI-2017-12-I.0, agreements ASI-INAF-2017-12- H0 and ASI-INFN-2017.13-H0, and its Space Science Data Center (SSDC) with agreements ASI-INAF-2022-14-HH.0 and ASI-INFN 2021-43-HH.0, and by the Istituto Nazionale di Astrofisica (INAF) and the Istituto Nazionale di Fisica Nucleare (INFN) in Italy. This research used data products provided by the IXPE Team (MSFC, SSDC, INAF, and INFN) and distributed with additional software tools by the High-Energy Astrophysics Science Archive Research Center (HEASARC), at NASA Goddard Space Flight Center (GSFC). JP and SST acknowledge support from the Academy of Finland grants 333112. POP acknowledges financial support from the French High Energy Programme of CNRS (PNHE) and from the French Space Agency (CNES). | en_US |
| dc.description.uri | https://arxiv.org/abs/2306.02740 | en_US |
| dc.format.extent | 10 pages | en_US |
| dc.genre | journal articles | en_US |
| dc.genre | preprints | en_US |
| dc.identifier | doi:10.13016/m2ypx5-2jvt | |
| dc.identifier.uri | https://doi.org/10.48550/arXiv.2306.02740 | |
| dc.identifier.uri | http://hdl.handle.net/11603/28264 | |
| dc.language.iso | en_US | en_US |
| dc.relation.isAvailableAt | The University of Maryland, Baltimore County (UMBC) | |
| dc.relation.ispartof | UMBC Center for Space Sciences and Technology | |
| dc.relation.ispartof | UMBC Faculty Collection | |
| dc.rights | This work was written as part of one of the author's official duties as an Employee of the United States Government and is therefore a work of the United States Government. In accordance with 17 U.S.C. 105, no copyright protection is available for such works under U.S. Law. | en_US |
| dc.rights | Public Domain Mark 1.0 | * |
| dc.rights.uri | http://creativecommons.org/publicdomain/mark/1.0/ | * |
| dc.title | X-ray polarimetry and spectroscopy of the neutron star low-mass X-ray binary GX 9+9: an in-depth study with IXPE and NuSTAR | en_US |
| dc.type | Text | en_US |
| dcterms.creator | https://orcid.org/0000-0002-6548-5622 | en_US |