Basic research on salt neutrino detector for ultra high energy neutrino

超高能中微子盐中微子探测器基础研究

• 批准号: 14540274
• 负责人: CHIBA Masami
• 金额: $ 2.3万
• 依托单位: Tokyo Metropolitan University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2002
• 资助国家: 日本
• 起止时间: 2002 至 2003
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-14540274/
• 关键词: Ultra high energy neutrino; Rock salt; GZK effect; Askaryan effect; Ultra high energy cosmic; Perturbation cavity resonator method; Cherenkov effect; Radio Wave; 超高エネルギー; ニュートリノ; 干渉性チェレンコフ効果; 電波検出; 電波減衰長

Ultra high energy (UHE) neutrino should be generated by GZK effect by a reaction between UHE cosmic ray and cosmic microwave background. UHE cosmic ray loses the energy by the effect UHE neutrino should be generated at the big bang or a sort of active galactic nuclei etc. Neutrino is the highest energy particle possible to travel very long cosmic distance. Therefore only UHE neutrino gives us directly information of high energy state at the big bang or so. The flux of UHE neutrino is very low, so we need very massive detection media to detect. We pay attention to natural rock salt mine which has a huge mass and long attenuation length for radio wave. Radio wave could be generated through Askaryan effect by electromagnetic shower occurred at the interaction between UHE neutrino and rock salt. Askaryan effect is essentially a coherent Cherenkov effect between excess electrons in the electromagnetic shower. We measured the attenuation length at 1GHz and 0.3GHz by a perturbation cavity resonator method. The summary of the measurement is as follows.1)The largest attenuation length (200m-500m) will be between 0.5GHz and 2GHz at the synthetic and Hockley sample (Texas).2)Economical antenna array with the spacing around 350m could detect GZK neutrino.3)The attenuation length has frequency dependence in rock salts.4)The attenuation length of Hockley increases with respect the frequency from 0.3GHz to 1GHz. Water in rock salt crystal or brine closed inside at the rock salt may shortens the attenuation length in the frequency range.

超高能中微子是由超高能宇宙线与宇宙微波背景辐射相互作用产生的GZK效应。UHE宇宙射线通过UHE中微子的作用失去能量，中微子应该是在大爆炸或一种活动星系核等产生的。中微子是可能在很长的宇宙距离内旅行的最高能量粒子。因此，只有UHE中微子能直接给出大爆炸前后高能态的信息。UHE中微子的通量非常低，因此我们需要非常大量的探测介质来进行探测。天然岩盐矿是一个质量巨大、电波衰减长度长的矿山，受到人们的广泛关注。UHE中微子与岩盐相互作用产生的电磁簇射可以通过Askaryan效应产生无线电波。Askaryan效应实质上是电磁簇射中多余电子之间的相干切伦科夫效应。用微扰谐振腔法测量了1GHz和0.3GHz的衰减长度。测量结果总结如下：1）最大衰减长度（200 m-500 m）在合成样品和Hockley样品（Texas）上的衰减长度将在0.5 GHz-2 GHz之间。2）间距在350 m左右的经济型天线阵列可以探测到GZK中微子。3）岩盐中的衰减长度具有频率依赖性。4）从0.3GHz到1GHz，Hockley的衰减长度随频率的增加而增加。岩盐晶体中的水或封闭在岩盐内部的盐水可缩短频率范围内的衰减长度。

项目成果

Measurement of Complex Permittivity in the UHF Band Using a Perturbed Cavity Resonator without Sample Insertion Holes

使用无样品插入孔的微扰腔谐振器测量 UHF 频段的复介电常数

• 发表时间: 2003
• 期刊: Memoirs of Graduate School of Engineering, Tokyo Metropolitan University No.53
• 作者: M.Chiba;T.Kamijo;O.Yasuda;Y.Chikashige;T.Kon;Y.Takeoka;R.Yoshida;Toshio Kamijo;Toshio Kamijo
• 通讯作者: Toshio Kamijo

O.Yasuda: "Neutrino factories : Physics potential and present status,"Proceedings of Beyond02 (IOP Bristol, 2003, eds.Klapdor-Klein grothaus). 419-434 (2003)

O.Yasuda：“中微子工厂：物理潜力和现状”，Beyond02 论文集（IOP 布里斯托尔，2003 年，eds.Klapdor-Klein grothaus）。

O.Yasuda: "Physics potential and present status of neutrino factories"Proceedings of the Third International Workshop (NOON2001). 259-268 (2002)

O.Yasuda：“中微子工厂的物理潜力和现状”第三届国际研讨会论文集（NOON2001）。

Salt neutrino detector for ultrahigh-energy neutrinos

超高能中微子盐中微子探测器

• 发表时间: 2004
• 期刊: Physics of Atomic Nuclei 67
• 作者: M.Chiba;T.Kamijo;O.Yasuda;Y.Chikashige;T.Kon;Y.Takeoka;R.Yoshida
• 通讯作者: R.Yoshida

H.Minakata, H.Sugiyama, O.Yasuda, K.Inoue, F.Suekane: "Reactor measurement of θ(13) and its complementarity to long-baseline experiments"Physical Review D. 68(3). 033017-1-033017-12 (2003)

H.Minakata、H.Sugiyama、O.Yasuda、K.Inoue、F.Suekane：“θ(13) 的反应器测量及其对长基线实验的补充”物理评论 D. 68(3)。 033017-12 (2003)