Absolute laser-intensity measurement and online monitor calibration using a calorimeter at a soft X-ray free-electron laser beamline in SACLA
Absolute laser-intensity measurement and online monitor calibration using a calorimeter at a soft X-ray free-electron laser beamline in SACLA
复制标题
在 SACLA 的软 X 射线自由电子激光束线上使用量热计进行绝对激光强度测量和在线监视器校准
DOI：
10.1016/j.nima.2018.03.045
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发表时间：
2018
期刊：
影响因子：
--
通讯作者：
T. Ishikawa
中科院分区：
文献类型：
--
作者：
Takahiro Tanaka;Masahiro Kato;N. Saito;S. Owada;K. Tono;M. Yabashi;T. Ishikawa
本文报道了在日本SPring-8埃紧凑型自由电子激光器（SACLA）上对一条全新的自由电子激光光束线BL-1进行的自由电子激光绝对强度测量和在线强度监测器的标定。为了测量自由电子激光的绝对强度，我们使用了最初为硬X射线范围内的自由电子激光开发的室温量热计。利用该量热计，在25 ~ 150 eV光子能量范围内，对基于氩气光电离的BL 1气体监测器（GMs）的强度监测器进行了在线标定。在1 μ J ~ 100 μ J的脉冲能量范围内，量热计和GM的信号具有良好的相关性，其上限几乎等于BL 1处的最大脉冲能量。此外，GM的校准结果，测量的光谱响应度，演示了一个特征的光子能量依赖性由于库珀最小值的发生在氩气的总电离截面。这些结果验证了在特定光子能量范围内使用室温量热计测量自由电子激光绝对强度的可行性。
This paper reports measurement of the absolute intensity of free-electron laser (FEL) and calibration of online intensity monitors for a brand-new FEL beamline BL1 at SPring-8 Angstrom Compact free-electron LAser (SACLA) in Japan. To measure the absolute intensity of FEL, we used a room-temperature calorimeter originally developed for FELs in the hard X-ray range. By using the calorimeter, we calibrated online intensity monitors of BL1, gas monitors (GMs), based on the photoionization of argon gas, in the photon energy range from 25 eV to 150 eV. A good correlation between signals obtained from the calorimeter and GMs was observed in the pulse energy range from 1 μ J to 100 μ J, where the upper limit is nearly equal to the maximum pulse energy at BL1. Moreover, the calibration result of the GMs, measured in terms of the spectral responsivity, demonstrates a characteristic photon-energy dependence owing to the occurrence of the Cooper minimum in the total ionization cross-section of argon gas. These results validate the feasibility of employing the room-temperature calorimeter in the measurement of absolute intensity of FELs over the specified photon energy range.
影响因子：
35
作者：
Ackermann, W.;Asova, G.;Zapfe, K.
通讯作者：
Zapfe, K.