Capitanio, FiammaFabiani, SergioGnarini, AndreaUrsini, FrancescoFerrigno, CarloMatt, GiorgioPoutanen, JuriCocchi, MassimoMikusincova, RomanaFarinelli, RubenBianchi, StefanoKajava, Jari J.E.Muleri, FabioSanchez-Fernandez, CeliaSoffitta, PaoloWu, KinwahAgudo, IvanAntonelli, L.A.Bachetti, MatteoBaldini, LucaBaumgartner, Wayne H.Bellazzini, RonaldoBongiorno, Stephen D.Bonino, RaffaellaBrez, AlessandroBucciantini, NiccolòCastellano, SimoneCavazzuti, ElisabettaCiprini, StefanoCosta, EnricoRosa, Alessandra DeMonte, Ettore DelGesu, Laura DiLalla, Niccolo DiMarco, Alessandro DiDonnarumma, ImmacolataDoroshenko, VictorDovčiak, MichalEhlert, Steven R.Enoto, TeruakiEvangelista, YuriFerrazzoli, RiccardoGarcia, Javier A.Gunji, ShuichiHayashida, KiyoshiHeyl, JeremyIwakiri, WataruJorstad, Svetlana G.Karas, VladimirKitaguchi, TakaoKolodziejczak, Jeffery J.Krawczynski, HenricMonaca, Fabio LaLatronico, LucaLiodakis, IoannisMaldera, SimoneManfreda, AlbertoMarin, FréedèricMarinucci, AndreaMarscher, Alan P.Marshall, Herman L.Mitsuishi, IkuyukiMizuno, TsunefumiNg, C.-Y.O'Dell, Stephen L.Omodei, NicolaOppedisano, ChiaraPapitto, AlessandroPavlov, George G.Peirson, Abel L.Perri, MatteoPesce-Rollins, MelissaPetrucci, Pierre-OlivierPilia, MauraPossenti, AndreaPuccetti, SimonettaRamsey, Brian D.Rankin, JohnRatheesh, AjayRomani, Roger W.Sgrò, CarmeloSlane, PatrickSpandre, GloriaTamagawa, ToruTavecchio, FabrizioTaverna, RobertoTawara, YuzuruTennant, Allyn F.Thomas, Nicholas E.Tombesi, FrancescoTrois, AlessioTsygankov, Sergey S.Turolla, RobertoVink, JaccoWeisskopf, Martin C.Xie, FeiZane, Silvia2023-07-122023-07-122023-02-01F. Capitanio, S. Fabiani, A. Gnarini, F. Ursini, C. Ferrigno, G. Matt, J. Poutanen, M. Cocchi, R. Mikusincova, R. Farinelli, S. Bianchi, J.J.E. Kajava, F. Muleri, C. Sanchez-Fernandez, P. Soffitta, K. Wu, 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, S. Ciprini, E. Costa, A.D. Rosa, E.D. Monte, L.D. Gesu, N.D. Lalla, A.D. Marco, I. Donnarumma, V. Doroshenko, M. Dovciak, 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, T. Kitaguchi, J.J. Kolodziejczak, H. Krawczynski, F.L. Monaca, L. Latronico, I. Liodakis, S. Maldera, A. Manfreda, F. Marin, A. Marinucci, A.P. Marscher, H.L. Marshall, I. Mitsuishi, T. Mizuno, 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, R.W. Romani, C. Sgrò, P. Slane, G. Spandre, 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, F. Xie, S. Zane. 2023. "Polarization properties of the weakly magnetized neutron star X-ray binary GS 1826-238 in the high soft state" The Astrophysical Journal: an international review of astronomy and astronomical physics, Volume 943, Issue 2, pp.129-129. https://doi.org/10.3847/1538-4357/acae880004-637X1538-4357https://hdl.handle.net/2144/46443The launch of the Imaging X-ray Polarimetry Explorer (IXPE) on 2021 December 9 has opened a new window in X-ray astronomy. We report here the results of the first IXPE observation of a weakly magnetized neutron star, GS 1826-238, performed on 2022 March 29-31 when the source was in a high soft state. An upper limit (99.73% confidence level) of 1.3% for the linear polarization degree is obtained over the IXPE 2-8 keV energy range. Coordinated INTEGRAL and NICER observations were carried out simultaneously with IXPE. The spectral parameters obtained from the fits to the broad-band spectrum were used as inputs for Monte Carlo simulations considering different possible geometries of the X-ray emitting region. Comparing the IXPE upper limit with these simulations, we can put constraints on the geometry and inclination angle of GS 1826-238.p. 129en-US© 2023. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.https://creativecommons.org/licenses/by/4.0/Astronomical and space sciencesAtomic, molecular, nuclear, particle and plasma physicsPhysical chemistry (incl. structural)Astronomy & astrophysicsArticle2023-02-0710.3847/1538-4357/acae880000-0001-7396-3332 (Marscher, Alan P)776488