A cryogenic half-wave plate polarimeter using a superconducting magnetic bearing
A cryogenic half-wave plate polarimeter using a superconducting magnetic bearing
复制标题
使用超导磁力轴承的低温半波片旋光仪
DOI：
10.1117/12.893669
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发表时间：
2011
期刊：
影响因子：
--
通讯作者：
K. Zilic
中科院分区：
文献类型：
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作者：
J. Klein;A. Aboobaker;P. Ade;F. Aubin;C. Baccigalupi;C. Bao;J. Borrill;D. Chapman;J. Didier;M. Dobbs;B. Gold;W. Grainger;S. Hanany;J. Hubmayr;S. Hillbrand;J. Grain;A. Jaffe;Bradley R. Johnson;T. Jones;T. Kisner;A. Korotkov;S. Leach;Adrian T. Lee;L. Levinson;M. Limon;K. MacDermid;T. Matsumura;A. Miller;M. Milligan;E. Pascale;D. Polsgrove;N. Ponthieu;K. Raach;B. Reichborn;I. Sagiv;R. Stompor;H. Tran;M. Tristram;G. Tucker;A. Yadav;M. Zaldarriaga;K. Zilic
我们提出了超导磁轴承（SMB）的设计和测量性能，成功地用作E和B实验（EBEX）的半波片偏振计在其北美试飞的旋转机构。EBEX是NASA支持的气球实验，旨在测量宇宙微波背景的偏振。在该实施方式中，将半波片安装到在4 K的吸收温度下操作的SMB的转子。我们展示了强大的，远程操作的气球搭载的有效载荷，角编码精度为0.01°。我们发现转速变化为0.2%RMS。我们测量振动模式，并发现它们与一个简单的SMB模型是一致的。我们在探测器和读出器中寻找但没有发现磁场干扰。在对这种干扰进行5分钟积分后，我们将接收机噪声电平的上限设置为3%。在2 Hz旋转时，我们测量到56 mW的功耗。如果这种功耗降低，这样的SMB实现是低噪声空间应用的候选者，因为没有粘滑摩擦和低磨损。
We present the design and measured performance of the superconducting magnetic bearing (SMB) that was used successfully as the rotation mechanism in the half-wave plate polarimeter of the E and B Experiment (EBEX) during its North American test flight. EBEX is a NASA-supported balloon-borne experiment that is designed to measure the polarization of the cosmic microwave background. In this implementation the half-wave plate is mounted to the rotor of an SMB that is operating at the sink temperature of 4 K. We demonstrate robust, remote operation on a balloon-borne payload, with angular encoding accuracy of 0.01°. We find rotational speed variation to be 0.2% RMS. We measure vibrational modes and find them to be consistent with a simple SMB model. We search for but do not find magnetic field interference in the detectors and readout. We set an upper limit of 3% of the receiver noise level after 5 minutes of integration on such interference. At 2 Hz rotation we measure a power dissipation of 56 mW. If this power dissipation is reduced, such an SMB implementation is a candidate for low-noise space applications because of the absence of stick-slip friction and low wear.