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arXiv · 1412.1869

An X-ray Spectroscopic Search for Dark Matter in the Perseus Cluster with Suzaku

Takayuki Tamura·Ryo Iizuka·Yoshitomo Maeda·Kazuhisa Mitsuda·Noriko Y. Yamasaki
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Abstract

We present the results from deep Suzaku observations of the central region of the Perseus cluster. Bulbul et al. (2014) reported the detection by XMM-Newton instruments of an unidentified X-ray emission line at an energy around 3.5keV in spectra for the Perseus and other clusters. They argued for a possibility of the decay of sterile neutrino, a dark matter candidate. We examine Suzaku X-ray Imaging Spectrometer (XIS) spectra of the Perseus cluster for evidence in the 3.5keV line and other possible dark matter features in the 2-6keV energy band. In order to search for and constrain a weak line feature with the XIS, observations of the Crab nebula are used to evaluate the system's effective area. We found no line feature at the claimed position with a systematic line flux upper limit at a half (1.5eV in line equivalent width) of the claimed best-fit value by Bulbul et al. We discuss this inconsistency in terms of instrumental calibration errors and modeling of continuum emission. Future prospects for high-energy resolution spectroscopy with ASTRO-H are presented.

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Takayuki Tamura, Ryo Iizuka, Yoshitomo Maeda, Kazuhisa Mitsuda, Noriko Y. Yamasaki. 2014-12-22. An X-ray Spectroscopic Search for Dark Matter in the Perseus Cluster with Suzaku. https://doi.org/10.1093/pasj%2Fpsu156

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