New CTI Correction Method for the Spaced-Row Charge Injection of the Suzaku X-Ray Imaging Spectrometer

Hideki Uchiyama; Midori Ozawa; Hironori Matsumoto; Takeshi Go Tsuru; Katsuji Koyama; Masashi Kimura; Hiroyuki Uchida; Hiroshi Nakajima; Kiyoshi Hayashida; Hiroshi Tsunemi; Hideyuki Mori; Aya Bamba; Masanobu Ozaki; Tadayasu Dotani; Dai Takei; Hiroshi Murakami; Koji Mori; Yoshitaka Ishisaki; Takayoshi Kohmura; Gregory Prigozhin; Steve Kissel; Eric Miller; Beverly LaMarr; Marshall Bautz

doi:10.1093/pasj/61.sp1.s9

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arXiv · 0810.0873

New CTI Correction Method for the Spaced-Row Charge Injection of the Suzaku X-Ray Imaging Spectrometer

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Abstract

The charge transfer inefficiency (CTI) of the X-ray CCDs on board the Suzaku satellite (X-ray Imaging Spectrometers; XIS) has increased since the launch due to radiation damage, and the energy resolution has been degraded. To improve the CTI, we have applied a spaced-row charge injection (SCI) technique to the XIS in orbit; by injecting charges into CCD rows periodically, the CTI is actively decreased. The CTI in the SCI mode depends on the distance between a signal charge and a preceding injected row, and the pulse height shows periodic positional variations. Using in-flight data of onboard calibration sources and of the strong iron line from the Perseus cluster of galaxies, we studied the variation in detail. We developed a new method to correct the variation. By applying the new method, the energy resolution (FWHM) at 5.9 keV at March 2008 is ~155 eV for the front-illuminated CCDs and ~175 eV for the back-illuminated CCD.

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Hideki Uchiyama, Midori Ozawa, Hironori Matsumoto, Takeshi Go Tsuru, Katsuji Koyama, Masashi Kimura, Hiroyuki Uchida, Hiroshi Nakajima, Kiyoshi Hayashida, Hiroshi Tsunemi, Hideyuki Mori, Aya Bamba, Masanobu Ozaki, Tadayasu Dotani, Dai Takei, Hiroshi Murakami, Koji Mori, Yoshitaka Ishisaki, Takayoshi Kohmura, Gregory Prigozhin, Steve Kissel, Eric Miller, Beverly LaMarr, Marshall Bautz. 2008-10-06. New CTI Correction Method for the Spaced-Row Charge Injection of the Suzaku X-Ray Imaging Spectrometer. https://doi.org/10.1093/pasj%2F61.sp1.s9

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