arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2203.09685physics.ins-detastro-ph.IMgr-qc
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KAGRA低温恒温器的振动分析

Vibration Analysis of KAGRA Cryostat at Cryogenic Temperature

Rishabh Bajpai, Takayuki Tomaru, Nobuhiro Kimura, Takafumi Ushiba, Kazuhiro Yamamoto, Toshikazu Suzuki, Tohru Honda

摘要:

KAGRA使用低温技术将其蓝宝石测试质量冷却至20 K,以降低热噪声。然而,低温制冷机的振动和低温恒温器的结构共振耦合到测试质量,并可能污染检测器的灵敏度。我们进行了振动分析的冷却系统在低温下,研究其对探测器灵敏度的影响。我们的测量表明,屏蔽振动低于1赫兹不受制冷机运行或结构共振,并遵循地面运动。在1-100 Hz的屏蔽的本底噪声被观察到是2-3个数量级大于地震运动,即使没有制冷机操作。低温制冷机的运行不会改变噪声基底,但在整个频谱(1-100 Hz)上观察到2.0 Hz峰值及其谐波。这些结果用于计算冷却系统振动与试验质量的耦合。我们的结论是,从冷却系统的振动不限制KAGRA设计的灵敏度。

英文摘要:

KAGRA uses cryogenics to cool its sapphire test masses down to 20 K to reduce the thermal noise. However, cryocooler vibration and structural resonances of the cryostat couple to test mass and can contaminate the detector sensitivity. We performed vibration analysis of the cooling system at cryogenic temperature to study its impact on detector sensitivity. Our measurement show shield vibration below 1 Hz is not impacted by cryocooler operation or structural resonances and follows ground motion. The noise floor of the shield in 1-100 Hz was observed to be 2-3 order of magnitude larger than seismic motion even without cryocooler operation. The operation of cryocoolers does not change the noise floor, but 2.0 Hz peaks and their harmonics were observed over the entire spectrum (1-100 Hz). These results were used to calculate the coupling of cooling system vibration to the test mass. We conclude that vibration from the cooling system does not limit KAGRA design sensitivity.

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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