• Title/Summary/Keyword: high energy physics

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Pulsed γ-ray emission from magnetar 1E 2259+586

  • Wu, Jason Hung Kit;Hui, Chung Yue;Huang, Regina Hsiu Hui;Kong, Albert Kwok Hing;Cheng, Kwong Sang;Takata, Jumpei;Tam, Pak Hin Thomas;Wu, Eric Man Ho;Liu, Joe
    • Journal of Astronomy and Space Sciences
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    • v.30 no.2
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    • pp.83-85
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    • 2013
  • Anomalous X-ray pulsars (AXPs) are thought to be magnetars which are young isolated neutron stars with extremely strong magnetic fields of > $10^{14}$ Gauss. Their tremendous magnetic fields inferred from the spin parameters provide a huge energy reservoir to power the observed X-ray emission. High-energy emission above 0.3 MeV has never been detected despite intensive search. Here, we present the possible Fermi Large Area Telescope (LAT) detection of ${\gamma}$-ray pulsations above 200 MeV from the AXP, 1E 2259+586, which puts the current theoretical models of ${\gamma}$-ray emission mechanisms of magnetars into challenge. We speculate that the high-energy ${\gamma}$-rays originate from the outer magnetosphere of the magnetar.

An embodiment of e-Science for High Energy Physics (고에너지물리 e-Science 연구환경의 구현)

  • Cho, Kihyeon;Kim, Hyunwoo
    • Proceedings of the Korea Contents Association Conference
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    • 2007.11a
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    • pp.231-233
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    • 2007
  • The e-Science for High Energy Physics is to study high energy physics anytime and anywhere even if we are not on-site of accelerator latboratories. The concepts are 1) data production, 2) data processing and 3) data publication. The data production is to do remote control and take shifts remotely. The data processing is to run jobs anytime, anywhere with grid farms. The data publication is to work together to publish papers using collaborative environment such as EVO (Enabling Virtual Organization) system. We apply this concept to high energy physics, espessically, CDF experiment and show the results.

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Evaluation of energy correction algorithm for signals of PET in heavy-ion cancer therapy device

  • Niu, Xiaoyang;Yan, Junwei;Wang, Xiaohui;Yang, Haibo;Ke, Lingyun;Chen, Jinda;Du, Chengming;Zhang, Xiuling;Zhao, Chengxin;Kong, Jie;Su, Hong
    • Nuclear Engineering and Technology
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    • v.52 no.1
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    • pp.101-108
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    • 2020
  • In order to solve the contradiction between requirements of high sampling rate for acquiring accurate energy information of pulses and large amount of data to be processed timely, the method with an algorithm to correct errors caused by reducing the sampling rate is normally used in front-end read-out system, which is conductive to extract accurate energy information from digitized waveform of pulse. The functions and effects of algorithms, which mainly include polynomial fitting with different fitting times, double exponential function fitting under different sampling modes, and integral area algorithm, are analyzed and evaluated, and some meaningful results is presented in this paper. The algorithm described in the paper has been used preliminarily in a prototype system of Positron Emission Tomography (PET) for heavy-ion cancer therapy facility.

Recent R&D on Oxide Scintillation Crystals for Radiation Detectors

  • Ishii, M.;Kobayashi, M.;Hara, K.;Tanaka, M.;Yamaga, I.;Miwa, K.;Ishibashi, H.;Usuki, Y.;Hirose, Y.
    • Proceedings of the Korea Association of Crystal Growth Conference
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    • 1997.06a
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    • pp.131-134
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    • 1997
  • Scintillation crystals for industrial field are used in fundamental physics i.e. nuclear and high energy physics experiments besides the medical imaging, process control and gauging, container inspection, mineral process etc. For the reason of limited marketability, there are not so many studies with emphasis paced on the crystal growth. The scintillation crystal is an important theme in the studies in the fundamental physics and researchers for crystal growth are expected participate it. The present work is partly supported by a Grant-in-Aid from the Japanese Ministry of Education, Science and Culture.

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SURFACE PROCESSING OF TOOLS AND COMPONENTS BY MEVVA SOURCE ION IMPLANTATION

  • Lin, W.L.;Sang, J.M.;Ding, X.J.;Yuan, X.M.;Xu, J.;Zhang, H.X.;Zhang, X.J.
    • Journal of the Korean Vacuum Society
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    • v.4 no.S2
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    • pp.106-114
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    • 1995
  • Direct implantation of metallic ion species has been employed in surface processing of industrial components and tools with very encouraging improvements in recent years. In spite of high technicla effectiveness, this new surface processing technique has not been extensively accepted by industries mainly because of high cost(capital and operating) compared with other competitive surface processing techniques. High current and large implantation area with eliminating the mass analyzer and the beam-scanning unit make metal vapor vacuum are(MEVVA)source ion implantation versatile, simple and cheap to operate and well suited to commercial surface processing. In this paper, the recent development of MEVVA source ion implantation technique ar Beijing Normal University has been reviewed and the results of production trials of several industrial components and tools implanted by MEVVA source ion implantation have been presented and discussed.

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