TY - JOUR

T1 - X-Ray Polarimetry Reveals the Magnetic-field Topology on Sub-parsec Scales in Tycho’s Supernova Remnant

AU - Ferrazzoli, Riccardo

AU - Slane, Patrick

AU - Prokhorov, Dmitry

AU - Zhou, Ping

AU - Vink, Jacco

AU - Bucciantini, Niccolò

AU - Costa, Enrico

AU - Di Lalla, Niccolò

AU - Di Marco, Alessandro

AU - Soffitta, Paolo

AU - Weisskopf, Martin C.

AU - Asakura, Kazunori

AU - Baldini, Luca

AU - Heyl, Jeremy

AU - Kaaret, Philip E.

AU - Marin, Frédéric

AU - Mizuno, Tsunefumi

AU - Ng, C.-y.

AU - Pesce-rollins, Melissa

AU - Silvestri, Stefano

AU - Sgrò, Carmelo

AU - Swartz, Douglas A.

AU - Tamagawa, Toru

AU - Yang, Yi-jung

AU - Agudo, Iván

AU - Antonelli, Lucio A.

AU - Bachetti, Matteo

AU - Baumgartner, Wayne H.

AU - Bellazzini, Ronaldo

AU - Bianchi, Stefano

AU - Bongiorno, Stephen D.

AU - Bonino, Raffaella

AU - Brez, Alessandro

AU - Capitanio, Fiamma

AU - Castellano, Simone

AU - Cavazzuti, Elisabetta

AU - Chen, Chien-ting

AU - Ciprini, Stefano

AU - De Rosa, Alessandra

AU - Del Monte, Ettore

AU - Di Gesu, Laura

AU - Donnarumma, Immacolata

AU - Doroshenko, Victor

AU - Dovčiak, Michal

AU - Ehlert, Steven R.

AU - Enoto, Teruaki

AU - Evangelista, Yuri

AU - Fabiani, Sergio

AU - Garcia, Javier A.

AU - Gunji, Shuichi

AU - Hayashida, Kiyoshi

AU - Iwakiri, Wataru

AU - Jorstad, Svetlana G.

AU - Kislat, Fabian

AU - Karas, Vladimir

AU - Kitaguchi, Takao

AU - Kolodziejczak, Jeffery J.

AU - Krawczynski, Henric

AU - La Monaca, Fabio

AU - Latronico, Luca

AU - Liodakis, Ioannis

AU - Maldera, Simone

AU - Manfreda, Alberto

AU - Marinucci, Andrea

AU - Marscher, Alan P.

AU - Marshall, Herman L.

AU - Matt, Giorgio

AU - Mitsuishi, Ikuyuki

AU - Muleri, Fabio

AU - Negro, Michela

AU - O’dell, Stephen L.

AU - Omodei, Nicola

AU - Oppedisano, Chiara

AU - Papitto, Alessandro

AU - Pavlov, George G.

AU - Peirson, Abel L.

AU - Perri, Matteo

AU - Petrucci, Pierre-olivier

AU - Pilia, Maura

AU - Possenti, Andrea

AU - Poutanen, Juri

AU - Puccetti, Simonetta

AU - Ramsey, Brian D.

AU - Rankin, John

AU - Ratheesh, Ajay

AU - Roberts, Oliver

AU - Romani, Roger W.

AU - Spandre, Gloria

AU - Tavecchio, Fabrizio

AU - Taverna, Roberto

AU - Tawara, Yuzuru

AU - Tennant, Allyn F.

AU - Thomas, Nicholas E.

AU - Tombesi, Francesco

AU - Trois, Alessio

AU - Tsygankov, Sergey S.

AU - Turolla, Roberto

AU - Wu, Kinwah

AU - Xie, Fei

AU - Zane, Silvia

PY - 2023/3/1

Y1 - 2023/3/1

N2 - Supernova remnants are commonly considered to produce most of the Galactic cosmic rays via diffusive shock acceleration. However, many questions regarding 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 degree of polarization of the X-ray synchrotron emission is 9% ± 2% averaged over the whole remnant, and 12% ± 2% at the rim, higher than the value of polarization of 7%–8% observed in the radio band. In the west region, the degree of polarization is 23% ± 4%. The degree of X-ray polarization in Tycho is higher than for Cassiopeia A, suggesting a more ordered magnetic field or a larger maximum turbulence scale. The measured tangential direction of polarization corresponds to the 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 orientation of the magnetic field is preferentially radially oriented due to hydrodynamical instabilities.

AB - Supernova remnants are commonly considered to produce most of the Galactic cosmic rays via diffusive shock acceleration. However, many questions regarding 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 degree of polarization of the X-ray synchrotron emission is 9% ± 2% averaged over the whole remnant, and 12% ± 2% at the rim, higher than the value of polarization of 7%–8% observed in the radio band. In the west region, the degree of polarization is 23% ± 4%. The degree of X-ray polarization in Tycho is higher than for Cassiopeia A, suggesting a more ordered magnetic field or a larger maximum turbulence scale. The measured tangential direction of polarization corresponds to the 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 orientation of the magnetic field is preferentially radially oriented due to hydrodynamical instabilities.

UR - https://www.mendeley.com/catalogue/b755056b-54f7-323c-80ae-d83375380c5a/

U2 - 10.3847/1538-4357/acb496

DO - 10.3847/1538-4357/acb496

M3 - Article

VL - 945

JO - Astrophysical Journal

JF - Astrophysical Journal

SN - 0004-637X

IS - 1

M1 - 52

ER -