Hitomi observations of the LMC SNR N 132 D: Highly redshifted X-ray emission from iron ejecta
Authors: Aharonian Hitomi Collaboration, Felix , Akamatsu Hiroki , Akimoto Fumie , Allen Steven W , Angelini Lorella , Audard Marc , Awaki Hisamitsu , Axelsson Magnus , Bamba Aya , Bautz Marshall W , Blandford Roger , Brenneman Laura W , Brown Gregory V , Bulbul Esra , Cackett Edward M , Chernyakova Maria , Chiao Meng P , Coppi Paolo S , Costantini Elisa , de Plaa Jelle , de Vries Cor P , den Herder Jan-Willem , Done Chris , Dotani Tadayasu , Ebisawa Ken , Eckart Megan E , Enoto Teruaki , Ezoe Yuichiro , Fabian Andrew C , Ferrigno Carlo , Foster Adam R , Fujimoto Ryuichi , Fukazawa Yasushi , Furuzawa Akihiro , Galeazzi Massimiliano , Gallo Luigi C , Gandhi Poshak , Giustini Margherita , Goldwurm Andrea , Gu Liyi , Guainazzi Matteo , Haba Yoshito , Hagino Kouichi , Hamaguchi Kenji , Harrus Ilana M , Hatsukade Isamu , Hayashi Katsuhiro , Hayashi Takayuki , Hayashida Kiyoshi , Hiraga Junko S , Hornschemeier Ann , Hoshino Akio , Hughes John P , Ichinohe Yuto , Iizuka Ryo , Inoue Hajime , Inoue Yoshiyuki , Ishida Manabu , Ishikawa Kumi , Ishisaki Yoshitaka , Iwai Masachika , Kaastra Jelle , Kallman Tim , Kamae Tsuneyoshi , Kataoka Jun , Katsuda Satoru , Kawai Nobuyuki , Kelley Richard L , Kilbourne Caroline A , Kitaguchi Takao , Kitamoto Shunji , Kitayama Tetsu , Kohmura Takayoshi , Kokubun Motohide , Koyama Katsuji , Koyama Shu , Kretschmar Peter , Krimm Hans A , Kubota Aya , Kunieda Hideyo , Laurent Philippe , Lee Shiu-Hang , Leutenegger Maurice A , Limousin Olivier , Loewenstein Michael , Long Knox S , Lumb David , Madejski Greg , Maeda Yoshitomo , Maier Daniel , Makishima Kazuo , Markevitch Maxim , Matsumoto Hironori , Matsushita Kyoko , McCammon Dan , McNamara Brian R , Mehdipour Missagh , Miller Eric D , Miller Jon M , Mineshige Shin , Mitsuda Kazuhisa , Mitsuishi Ikuyuki , Miyazawa Takuya , Mizuno Tsunefumi , Mori Hideyuki , Mori Koji , Mukai Koji , Murakami Hiroshi , Mushotzky Richard F , Nakagawa Takao , Nakajima Hiroshi , Nakamori Takeshi , Nakashima Shinya , Nakazawa Kazuhiro , Nobukawa Kumiko K , Nobukawa Masayoshi , Noda Hirofumi , Odaka Hirokazu , Ohashi Takaya , Ohno Masanori , Okajima Takashi , Ota Naomi , Ozaki Masanobu , Paerels Frits , Paltani Stéphane , Petre Robert , Pinto Ciro , Porter Frederick S , Pottschmidt Katja , Reynolds Christopher S , Safi-Harb Samar , Saito Shinya , Sakai Kazuhiro , Sasaki Toru , Sato Goro , Sato Kosuke , Sato Rie , Sato Toshiki , Sawada Makoto , Schartel Norbert , Serlemtsos Peter J , Seta Hiromi , Shidatsu Megumi , Simionescu Aurora , Smith Randall K , Soong Yang , Stawarz Łukasz , Sugawara Yasuharu , Sugita Satoshi , Szymkowiak Andrew , Tajima Hiroyasu , Takahashi Hiromitsu , Takahashi Tadayuki , Takeda Shin’ichiro , Takei Yoh , Tamagawa Toru , Tamura Takayuki , Tanaka Takaaki , Tanaka Yasuo , Tanaka Yasuyuki T , Tashiro Makoto S , Tawara Yuzuru , Terada Yukikatsu , Terashima Yuichi , Tombesi Francesco , Tomida Hiroshi , Tsuboi Yohko , Tsujimoto Masahiro , Tsunemi Hiroshi , Tsuru Takeshi Go , Uchida Hiroyuki , Uchiyama Hideki , Uchiyama Yasunobu , Ueda Shutaro , Ueda Yoshihiro , Uno Shin’ichiro , Urry C Megan , Ursino Eugenio , Watanabe Shin , Werner Norbert , Wilkins Dan R , Williams Brian J , Yamada Shinya , Yamaguchi Hiroya , Yamaoka Kazutaka , Yamasaki Noriko Y , Yamauchi Makoto , Yamauchi Shigeo , Yaqoob Tahir , Yatsu Yoichi , Yonetoku Daisuke , Zhuravleva Irina , Zoghbi Abderahmen 
Published: December 2017

Abstract
We present Hitomi observations of N 132 D, a young, X-ray bright, O-rich core-collapse supernova remnant in the Large Magellanic Cloud (LMC). Despite a very short observation of only 3.7 ks, the Soft X-ray Spectrometer (SXS) easily detects the line complexes of highly ionized S K and Fe K with 16–17 counts in each. The Fe feature is measured for the first time at high spectral resolution. Based on the plausible assumption that the Fe K emission is dominated by He-like ions, we find that the material responsible for this Fe emission is highly redshifted at ∼ 800 km s−1 compared to the local LMC interstellar medium (ISM), with a 90% credible interval of 50–1500 km s−1 if a weakly informative prior is placed on possible line broadening. This indicates (1) that the Fe emission arises from the supernova ejecta, and (2) that these ejecta are highly asymmetric, since no blueshifted component is found. The S K velocity is consistent with the local LMC ISM, and is likely from swept-up ISM material. These results are consistent with spatial mapping that shows the He-like Fe concentrated in the interior of the remnant and the S tracing the outer shell. The results also show that even with a very small number of counts, direct velocity measurements from Doppler-shifted lines detected in extended objects like supernova remnants are now possible. Thanks to the very low SXS background of ∼ 1 event per spectral resolution element per 100 ks, such results are obtainable during short pointed or slew observations with similar instruments. This highlights the power of high-spectral-resolution imaging observations, and demonstrates the new window that has been opened with Hitomi and will be greatly widened with future missions such as the X-ray Astronomy Recovery Mission (XARM) and Athena.