A development of HBD for the J-PARC E16 experiment
A development of HBD for the J-PARC E16 experiment
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为 J-PARC E16 实验开发 HBD
DOI：
10.1016/j.nima.2010.06.340
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发表时间：
2011
期刊：
影响因子：
--
通讯作者：
他13名
中科院分区：
文献类型：
--
作者：
K. Aoki;Y. Komatsu;K. Ozawa;他13名
手性对称的自发破缺被认为是强子质量的起源。在有限密度下，手性对称性有望（部分）恢复，而强子的质量预计会减少，即使在正常的核密度下也是如此。提出了在有限密度环境下通过矢量介子的质量修正来研究质量起源的J-PARC E16实验。在p+A反应中产生的矢量介子的质量是通过电子-正电子衰变来测量的。要进行电子识别，需要具有大接受度和精细分割的切伦科夫探测器。HBD是理想的；它是一个无镜无窗的切伦科夫探测器，上面有一堆气体电子倍增器（GEMs）， CsI在上面蒸发。cf4作为放大气体和切伦科夫散热器。我们已经开发了一个用于J-PARC E16实验的HBD原型。它由两层厚度为100μm的液晶聚合物（LCP） GEMs构成，在最上面的表面蒸发CsI。与常规的50μm Kapton-GEMs相比，使用较厚的GEMs可以在第一阶段获得更大的增益，并且可以耐受火花。当阈值为~ 16个电子时，介子抑制因子可以达到100，这是E16实验所需的。用正电子束流进行了束流测试，样机成功地探测到了切伦科夫辐射。观察到的光电子数约为5-6个。虽然这些结果不能令人满意地达到100的介子抑制因子和合理的效率，在这一点上，光电阴极和气体纯度有望朝着目标的改进。
Spontaneous breaking of the chiral symmetry is considered to be the origin of hadron mass. The chiral symmetry is expected to be (partially) restored in finite density and the hadron mass is predicted to decrease, even at the normal nuclear density. The J-PARC E16 experiment was proposed to investigate the origin of the mass through the mass modification of vector mesons in a finite density environment. The masses of vector mesons, which are produced in p+A reactions, are measured through the electron–positron decays. A Cherenkov detector with a large acceptance and with fine segmentations is required for the electron identification. HBD is ideal for the purpose; it is a mirror-less, windowless Cherenkov detector with a stack of Gas Electron Multipliers (GEMs) on top of which CsI is evaporated. CF4acts as amplification gas and as Cherenkov radiator. We have developed a prototype of HBD for the J-PARC E16 experiment. It is constructed with two layers of Liquid-Crystal-Polymer (LCP) GEMs with a thickness of 100μm each, on the uppermost surface CsI is evaporated. The use of thicker GEMs leads to a larger gain at the first stage and to tolerance to sparks, compared to regular 50μm Kapton-GEMs. With a threshold at ∼16 electrons, a pion rejection factor of 100 can be achieved, which is required for the E16 experiment. A beam test was performed with a positron beam and the prototype successfully detected the Cherenkov radiation. The number of photoelectrons observed was about 5–6. Although these results were not satisfactory to reach a pion rejection factor of 100 with a reasonable efficiency at this point, improvements towards the goal are expected from photocathode and gas purity.
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CsI 光电阴极 GEM 探测器的光电子采集和工作参数
影响因子：
1.8
作者：
B. Azmoun;A. Caccavano;Z. Citron;M. Durham;T. Hemmick;J. Kamin;M. Rumore;C. Woody
通讯作者：
C. Woody
为 PHENIX 实验开发在纯 CF4 中运行的三重 GEM 紫外光子探测器
DOI：
10.1016/j.nima.2003.12.018
发表时间：
2003
影响因子：
1.4
作者：
A. Kozlov;I. Ravinovich;L. Shekhtman;Z. Fraenkel;M. Inuzuka;I. T. W. I. O. Science;Rehovot;Israel;Budker Institute of Nuclear Physics;Novosibirsk;Russia.;U. Tokyo;Tokyo;Japan.
通讯作者：
Japan.
phi-->e e- 和 phi-->K K- 通道中衰变宽度的核物质修饰。
影响因子：
8.6
作者：
F. Sakuma;J. Chiba;H. En’yo;Y. Fukao;H. Funahashi;H. Hamagaki;M. Ieiri;M. Ishino;H. Kanda;M. Kitaguchi;S. Mihara;K. Miwa;T. Miyashita;T. Murakami;R. Muto;T. Nakura;M. Naruki;K. Ozawa;O. Sasaki;M. Sekimoto;T. Tabaru;K. Tanaka;M. Togawa;S. Yamada;S. Yokkaichi;Y. Yoshimura
通讯作者：
Y. Yoshimura
正常核密度下 cp 介子的介质内修饰的证据。
DOI：
--
发表时间：
2007
期刊：
Phys. Rev. Lett. 98
影响因子：
--
作者：
T.Sugitate;T.Sugitate;D.V.Aleksandrov 他;T.Sugitate;D.V.Aleksandrov et al.;F.Sakuma et al.;R.Muto et al.;S.Yokkaichi et al.;F.Sakuma et al.;R.Muto et al.
通讯作者：
R.Muto et al.