X-Ray Polarization of the Eastern Lobe of SS 433
: Kaaret P, Ferrazzoli R, Silvestri S, Negro M, Manfreda A, Wu K, Costa E, Soffitta P, Safi-Harb S, Poutanen J, Veledina A, Marco AD, Slane P, Bianchi S, Ingram A, Romani RW, Cibrario N, Intyre BM, Mikus̆incová R, Ratheesh A, Steiner JF, Svoboda J, Tugliani S, Agudo I, Antonelli LA, Bachetti M, Baldini L, Baumgartner WH, Bellazzini R, Bongiorno SD, Bonino R, Brez A, Bucciantini N, Capitanio F, Castellano S, Cavazzuti E, Chen C, Ciprini S, Rosa AD, Monte ED, Gesu LD, Lalla ND, Donnarumma I, Doroshenko V, Dovčiak M, Ehlert SR, Enoto T, Evangelista Y, Fabiani S, García JA, Gunji S, Hayashida K, Heyl J, Iwakiri W, Jorstad SG, Karas V, Kislat F, Kitaguchi T, Kolodziejczak JJ, Krawczynski H, Monaca FL, Latronico L, Liodakis I, Maldera S, Marin F, Marinucci A, Marscher AP, Marshall HL, Massaro F, Matt G, Mitsuishi I, Mizuno T, Muleri F, Ng C, O’Dell SL, Omodei N, Oppedisano C, Papitto A, Pavlov GG, Peirson AL, Perri M, Pesce-Rollins M, Petrucci P, Pilia M, Possenti A, Puccetti S, Ramsey BD, Rankin J, Roberts OJ, Sgrò C, Spandre G, Swartz DA, Tamagawa T, Tavecchio F, Taverna R, Tawara Y, Tennant AF, Thomas NE, Tombesi F, Trois A, Tsygankov SS, Turolla R, Vink J, Weisskopf MC, Xie F, Zane S
Publisher: Institute of Physics Publishing
: 2024
: Astrophysical Journal Letters
: The Astrophysical Journal Letters
: L12
: 961
: 1
: 2041-8213
DOI: https://doi.org/10.3847/2041-8213/ad103b
: https://dx.doi.org/10.3847/2041-8213/ad103b
: https://research.utu.fi/converis/portal/detail/Publication/381279088
How astrophysical systems translate the kinetic energy of bulk motion into the acceleration of particles to very high energies is a pressing question. SS 433 is a microquasar that emits TeV γ-rays indicating the presence of high-energy particles. A region of hard X-ray emission in the eastern lobe of SS 433 was recently identified as an acceleration site. We observed this region with the Imaging X-ray Polarimetry Explorer and measured a polarization degree in the range 38%–77%. The high polarization degree indicates the magnetic field has a well-ordered component if the X-rays are due to synchrotron emission. The polarization angle is in the range −12° to +10° (east of north), which indicates that the magnetic field is parallel to the jet. Magnetic fields parallel to the bulk flow have also been found in supernova remnants and the jets of powerful radio galaxies. This may be caused by interaction of the flow with the ambient medium.