X-ray polarimetry reveals the magnetic field topology on sub-parsec scales in Tycho's supernova remnant
Creators: name: Ferrazzoli, Riccardo
name: Slane, Patrick
name: Prokhorov, Dmitry
name: Zhou, Ping
name: Vink, Jacco
name: Bucciantini, Niccolò
name: Costa, Enrico
name: Di Lalla, Niccolò
name: Di Marco, Alessandro
name: Soffitta, Paolo
name: Weisskopf, Martin C.
name: Asakura, Kazunori
name: Baldini, Luca
name: Heyl, Jeremy
name: Kaaret, Philip E.
name: Marin, Frédéric
name: Mizuno, Tsunefumi
name: Ng, C. -Y.
name: Pesce-Rollins, Melissa
name: Silvestri, Stefano
name: Sgrò, Carmelo
name: Swartz, Douglas A.
name: Tamagawa, Toru
name: Yang, Yi-Jung
name: Agudo, Iván
name: Antonelli, Lucio A.
name: Bachetti, Matteo
name: Baumgartner, Wayne H.
name: Bellazzini, Ronaldo
name: Bianchi, Stefano
name: Bongiorno, Stephen D.
name: Bonino, Raffaella
name: Brez, Alessandro
name: Capitanio, Fiamma
name: Castellano, Simone
name: Cavazzuti, Elisabetta
name: Chen, Chien-Ting
name: Ciprini, Stefano
name: De Rosa, Alessandra
name: Del Monte, Ettore
name: Di Gesu, Laura
name: Donnarumma, Immacolata
name: Doroshenko, Victor
name: Dovčiak, Michal
name: Ehlert, Steven R.
name: Enoto, Teruaki
name: Evangelista, Yuri
name: Fabiani, Sergio
name: Garcia, Javier A.
name: Gunji, Shuichi
name: Hayashida, Kiyoshi
name: Iwakiri, Wataru
name: Jorstad, Svetlana G.
name: Kislat, Fabian
name: Karas, Vladimir
name: Kitaguchi, Takao
name: Kolodziejczak, Jeffery J.
name: Krawczynski, Henric
name: La Monaca, Fabio
name: Latronico, Luca
name: Liodakis, Ioannis
name: Maldera, Simone
name: Manfreda, Alberto
name: Marinucci, Andrea
name: Marscher, Alan P.
name: Marshall, Herman L.
name: Matt, Giorgio
name: Mitsuishi, Ikuyuki
name: Muleri, Fabio
name: Negro, Michela
name: O'Dell, Stephen L.
name: Omodei, Nicola
name: Oppedisano, Chiara
name: Papitto, Alessandro
name: Pavlov, George G.
name: Peirson, Abel L.
name: Perri, Matteo
name: Petrucci, Pierre-Olivier
name: Pilia, Maura
name: Possenti, Andrea
name: Poutanen, Juri
name: Puccetti, Simonetta
name: Ramsey, Brian D.
name: Rankin, John
name: Ratheesh, Ajay
name: Roberts, Oliver
name: Romani, Roger W.
name: Spandre, Gloria
name: Tavecchio, Fabrizio
name: Taverna, Roberto
name: Tawara, Yuzuru
name: Tennant, Allyn F.
name: Thomas, Nicholas E.
name: Tombesi, Francesco
name: Trois, Alessio
name: Tsygankov, Sergey S.
name: Turolla, Roberto
name: Wu, Kinwah
name: Xie, Fei
name: Zane, Silvia
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences
subject: FOS: Physical sciences

description: Supernova remnants are commonly considered to produce most of the Galactic cosmic rays via diffusive shock acceleration. However, many questions about the physical conditions at shock fronts, such as the magnetic-field morphology close to the particle acceleration sites, remain open. Here we report the detection of a localized polarization signal from some synchrotron X-ray emitting regions of Tycho's supernova remnant made by the Imaging X-ray Polarimetry Explorer. The derived polarization degree of the X-ray synchrotron emission is 9+/-2% averaged over the whole remnant, and 12+/-2% at the rim, higher than the 7-8% polarization value observed in the radio band. In the west region the polarization degree is 23+/-4%. The X-ray polarization degree in Tycho is higher than for Cassiopeia A, suggesting a more ordered magnetic-field or a larger maximum turbulence scale. The measured tangential polarization direction corresponds to a radial magnetic field, and is consistent with that observed in the radio band. These results are compatible with the expectation of turbulence produced by an anisotropic cascade of a radial magnetic-field near the shock, where we derive a magnetic-field amplification factor of 3.4+/-0.3. The fact that this value is significantly smaller than those expected from acceleration models is indicative of highly anisotropic magnetic-field turbulence, or that the emitting electrons either favor regions of lower turbulence, or accumulate close to where the magnetic-field orientation is preferentially radially oriented due to hydrodynamical instabilities.
description: 31 pages, 7 figures, 3 tables. Accepted for publication in ApJ. Revised version