Laser Compton Scattering LCS1922 1927 Laser Compton scattering

激光康普顿散射： Laser Compton Scattering (LCS)1922年，康普顿效应 获诺贝尔奖（ 1927） Laser Compton scattering b : Electron velocity /c q. L: Incident angle of laser photon q : Scattered angle of photon Bang! rons lect de Scattere Incident electrons Sca q ttered photo Ee ns Eg Head-on collision (q. L=0) Incident Photons El ex. Ee=3. 5 Ge. V, l=10. 6 mm Eg～ 22 Me. V

a 160 Me. V Linac at SDUV-FEL Injector + linac have been finished Photo injector 160 Me. V Linac FEL Radiator

第二部分：Si (Li)探测器, 电子学和数据获取系统 § ORTEC 电子学 § Si (Li) 探测器，由所仪 器中心自行研制 Crystal area (mm 2) 30(Φ 6) Crystal thickness (mm) 3. 8 Energy resolution at 5. 9 ke. V(e. V) 184 Thickness of Be windows (μm) 7. 5

Lab. VIEW 数据�取系� Single or multiplier measure Time or Event Time gap § 数据采集卡PCI 6132 § 采集卡面板BNC 2110 Rates; Counts; Passed time;

系统稳定性及系统漂移 § Fig. 1 the 5. 9 ke. V X-rays of 55 Fe as a § Fig. 2 the 6. 49 ke. V X-rays of 55 Fe as function of measurement sequence. a function of measurement sequence. F测量时间~7天，整个系统漂移为 2 e. V。系统的稳定 性好于 0. 3‰.

小结 X-ray detection system (Si (Li) detector + ORTEC electronics +Lab view procedure + PC) Detected X-ray range ≤ 60 ke. V Energy resolution ~180 e. V at 5. 9 ke. V Time resolution 0. 56 ns at 63. 5 ns with 0. 5μs TAC range System drift 2 e. V at 5. 9 ke. V System stability Better than 3‰ Acquisition efficiency ≥ 80% at 100 Hz. F探测器系统具有图形化显示，较好分辨率、良好稳定性、低 花费及性价比高的特点。 F此系统 已成功用于两期康普顿散射实验，至今仍在使用！

一期实验结果 Signal-to-Noise Ratio=1/406 W. Luo et al. , Rev. of Sci. Instrum, 81, 013304 (2010) First term experimental result X-ray peak 29. 1± 4. 4± 2. 1 ke. V X-ray width (δ) 7. 8± 2. 8± 0. 4 ke. V S/N 1/406 Peak photon 523± 209 Hz flux* *Normally 100 Me. V Linac operates with e-beam charge of 1. 0 n. C/pulse and repetition of 20 Hz. The measured value is 0. 012± 0. 005 s-1 in first term of LCS experiment at SINAP.

二期实验结果 考虑 1 ns的晃动, 粉红色的阴 影 部分为理论估计值范围 X-ray spectrum (Second term) X-ray peak 31. 73± 0. 23± 1. 64 ke. V X-ray width (δ) 0. 74± 0. 26± 0. 03 ke. V S/N 1/780 Peak photon 1. 7± 0. 3× 103 s-1 flux* W. Luo et al. , Applied Physics B (in print)

VME electronics for LEGS (� 文, 潘强岩) Pre-amp. Scintillator detector array Pre-amp. Signal Spec. Amp N 568 B 1) 16 Ch 2) Sharping time: 0. 2 us or 1 us CFD Interface: SIS 1100 -e. CMC+SIS 3104 (160 MByte/s) ADC: SIS 3320 1) 8 Ch 2) 40 -250 Mhz per ch 3) (32 MS/ch memory) 1) 32 Ch; 2) 250 MHz scaler CFD Scaler: SIS 3820 CFD Trigger ADC: 1) 16 Ch V 785 N 2) Conversion time: 2. 8 us /16 ch Delay TDC: V 1290 A 1) 32 Channel Multi-hit, 2) Readout rate: 33 Mb Note: 32 Channel electronics，two SIS 3320 and one V 785 N are used. DAQ+PC based on Linux/XP operation system

ADC： SIS 3320 Connecter: SIS 1100 Connector: SIS 3104 LC-LC 50/125 um Fibre 5 m VME机箱 6023 x 632 ADC: Two SIS 3320 Scaler: SIS 3820 Evaluation 2009