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arXiv 0811.4171astro-ph
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利用CDMS-II实验寻找太阳轴子

Search for Solar Axions with the CDMS-II Experiment

T. Bruch

摘要:

CDMS-II实验在非常低的背景环境中操作19个锗探测器,每个探测器的质量为250克。该实验最初是为了寻找暗物质而设计的,它还可以通过普里马科夫转换为光子来探测太阳轴子。晶体中X射线动量转移的布拉格条件允许Primakoff过程的相干放大。由于晶格相对于太阳的取向随白天而变化,因此预计太阳轴子转换的时间和能量具有独特的模式。低本底~1.5计数/千克/天/千电子伏,以及所有三个晶轴相对于太阳的准确方位的知识,使得CDMS-II实验对太阳轴子非常敏感。与太阳镜相比,< 1 keV的高质量区也可以有效探测。在实验装置中,单个晶体的交替取向提供了不同的太阳轴子转换模式,使得假阳性结果极不可能。对289千克-天照射量的分析结果导致对太阳轴子转换的零观测。该分析将轴子光子耦合常数的上限设定为g_{aγγ} < 2.6 x 10^{-9} GeV{-1},置信度为95%。

英文摘要:

The CDMS-II experiment operates 19 germanium detectors with a mass of 250g each in a very low background environment. Originally designed for the search for Dark Matter the experiment can also detect solar axions by Primakoff conversion to photons. The Bragg condition for X-ray momentum transfer in a crystal allows for coherent amplification of the Primakoff process. Since the orientation of the crystal lattice with respect to the Sun changes with daytime an unique pattern in time and energy of solar axion conversions is expected. The low background ~1.5 counts/kg/day/keV and knowledge of the exact orientation of all three crystal axes with respect to the Sun make the CDMS-II experiment very sensitive to solar axions. In contrast to helioscopes, the high mass region < 1 keV can also be probed effectively. The alternating orientations of the individual crystals in the experimental setup provide different patterns of solar axion conversion, making a false positive result extremely unlikely. The result of an analysis of 289 kg-days of exposure resulted in a null observation of solar axion conversion. This analysis sets an upper limit on the axion photon coupling constant of g_{aγγ} < 2.6 x 10^{-9} GeV{-1} at a 95% confidence level.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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