权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Study on Production of Coherent Light by SASE

SASE产生相干光的研究

基本信息

批准号：
10440075
负责人：
ISOYAMA Goro
金额：
$ 7.87万
依托单位：
OSAKA UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B).
财政年份：
1998
资助国家：
日本
起止时间：
1998 至 2000
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-10440075/
关键词：
SASE FEL INFRARED LINAC SINGLE PASS HIGH GAIN

项目摘要

We have conducted research on SASE (Self-Amplified Spontaneous Emission), which is expected to be a promising candidate for realizing X-ray lasers, in the infrared region using the L-band linac, which can accelerate a single-bunch electron beam with charge up to 91 nC.The characteristics of the electron beam have been measured over the wide energy range of 11-32 MeV to be the relative energy spread 1.1〜4%, charge per bunch > 20 nC, the bunch length 20-30 ps, and the normalized emittance 150〜250 π mm mrad. The expected performance of SASE has been estimated using these measured parameters and SASE theory based on the 1-dimensional model. The FEL parameters is 0.022 and the gain length is 0.128 m for the electron energy 11 MeV and the K value of the wiggler 1.47. It has been found the theory is applicable for the peak current > 1kA and the electron energy < 20 MeV.We have measured strong light emitted when the electron beam of 12.6 MeV passes through the wiggler with 6 cm period length and 32 periods. The peak power of the observed light increases from 1 W to 1 kW as the K-value increases. Since the K-value dependence of the power agrees quite well with the prediction of the theory, it is concluded that the observed light is due to SASE.We have measured wavelength spectra of SASE over the range of 80-180 μm using a grating monochromator. The spectral width of the fundamental peak ranges 2-3 %, and this value is slightly larger than 2.2-2.3 %, predicted by the theory. We have observed the second harmonic peak of SASE for the first time. We are quantitatively measuring characteristics of SASE and analyzing experimental results using 3-dimentional FEL simulation codes.

我们对SASE进行了研究自放大自发辐射（Self-Amplified Spontaneous Emission，简称SEE）是一种有望在红外波段实现X射线激光器的新技术，它能加速电荷高达91 nC的单束团电子束。在11-32 MeV的宽能量范围内，测量了电子束的特性，其相对能散为1.1 ~ 4%。每束团电荷> 20 nC，束团长度20-30 ps，归一化发射度150 × 250 π mm mrad。使用这些测量参数和基于一维模型的SASE理论估计了SASE的预期性能。当电子能量为11 MeV，摇摆器K值为1.47时，自由电子激光参数为0.022，增益长度为0.128 m。实验结果表明，该理论适用于峰值电流> 1 kA，电子能量< 20 MeV的情况。我们测量了12.6MeV的电子束通过周期长6cm、32个周期的摇摆器时的强发光。随着K值的增加，观察到的光的峰值功率从1 W增加到1 kW。我们用光栅单色仪测量了SASE在80-180 μm范围内的波长谱，并与实验结果进行了比较。基本峰的谱宽范围为2- 3%，比理论预测的2.2- 2.3%稍大。我们首次观察到了SASE的二次谐波峰。我们正在用三维自由电子激光模拟程序定量测量SASE的特性并分析实验结果。