The Polarized Cosmic Hand: IXPE Observations of PSR B1509−58/MSH 15−5<sup>2</sup>
Roger W. Romani, Josephine Wong, Niccolò Di Lalla, N. Omodei, Fei Xie, C.‐Y. Ng, Riccardo Ferrazzoli, Alessandro Di Marco, N. Bucciantini, M. Pilia, Patrick Slane, Martin C. Weisskopf, S. Johnston, M. Burgay, Wei Deng, Yi-Jung Yang, Shumeng Zhang, L. A. Antonelli, Matteo Bachetti, L. Baldini, W. H. Baumgartner, R. Bellazzini, S. Bianchi, Stephen D. Bongiorno, R. Bonino, A. Brez, Fiamma Capitanio, Simone Castellano, E. Cavazzuti, Chien‐Ting Chen, Nicolò Cibrario, S. Ciprini, E. Costa, Alessandra De Rosa, E. Del Monte, Laura Di Gesu, I. Donnarumma, Victor Doroshenko, Michal Dovčiak, Steven R. Ehlert, Teruaki Enoto, Y. Evangelista, Sergio Fabiani, Javier A. García, Shuichi Gunji, Kiyoshi Hayashida, Jeremy Heyl, W. Iwakiri, Ioannis Liodakis, P. Kaaret, V. Karas, Dawoon E. Kim, Takao Kitaguchi, Jeffery J. Kolodziejczak, H. Krawczynski, Fabio La Monaca, L. Latronico, G. Madejski, S. Maldera, Alberto Manfreda, Frédéric Marin, Andrea Marinucci, Alan P. Marscher, Herman L. Marshall, F. Massaro, G. Matt, R. Middei, Ikuyuki Mitsuishi, Tsunefumi Mizuno, Fabio Muleri, Michela Negro, Stephen L. O’Dell, C. Oppedisano, L. Pacciani, Alessandro Papitto, George G. Pavlov, M. Perri, M. Pesce-Rollins, Pierre-Olivier Petrucci, Andrea Possenti, Juri Poutanen, Simonetta Puccetti, Brian D. Ramsey, John Rankin, Ajay Ratheesh, O. J. Roberts, C. Sgró, Paolo Soffitta, G. Spandre, Douglas A. Swartz, Toru Tamagawa, F. Tavecchio, Roberto Taverna, Yuzuru Tawara, Allyn F. Tennant, Nicholas E. Thomas, Francesco Tombesi, A. Trois, Sergey S. Tsygankov, Roberto Turolla
Abstract
Abstract We describe IXPE polarization observations of the pulsar wind nebula (PWN) MSH 15−5 2 , the “Cosmic Hand.” We find X-ray polarization across the PWN, with B -field vectors generally aligned with filamentary X-ray structures. High-significance polarization is seen in arcs surrounding the pulsar and toward the end of the “jet,” with polarization degree PD > 70%, thus approaching the maximum allowed synchrotron value. In contrast, the base of the jet has lower polarization, indicating a complex magnetic field at significant angle to the jet axis. We also detect significant polarization from PSR B1509−58 itself. Although only the central pulse phase bin of the pulse has high individual significance, flanking bins provide lower-significance detections and, in conjunction with the X-ray image and radio polarization, can be used to constrain rotating vector model solutions for the pulsar geometry.