问题
问答题 简答题
在影响半导体探测器分辨率的各项因素中，电荷灵敏前置放大器的噪声也是重要的一项。什么是零电容噪声，什么是噪声斜率？如果零电容噪声为1keV，噪声斜率为0.03keV/pf，现知道由前放造成的能量展宽为7keV，哪么探测器的电容是多大？
答案
参考答案：
200pf
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在影响半导体探测器分辨率的各项因素中，电荷灵敏前置放大器的噪声也是重要的一项。什么是零电容噪声，什么是噪声斜率？如果零电容噪声为1keV，噪声斜率为0.03keV/pf，现知道由前放造成的能量展宽为7keV，哪么探测器的电容是多大？
参考答案：
200pf
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| ( )1. A. friends ( )2. A. respect ( )3. A. slow ( )4. A. bravely ( )5. A. opened ( )6. A. nowhere ( )7. A. hid ( )8. A. in ( )9. A. anxious ( )10. A. safe ( )11. A. must ( )12. A. hold up ( )13. A. when ( )14. A. popular ( )15. A. wanted ( )16. A. dirtier ( )17. A. money ( )18. A. reminded ( )19. A. first ( )20. A. large | B. neighbors B. pride B. busy B. reasonably B. locked B. somewhere B. lifted B. on B. cautious B. easy B. can B. hand out B. after B. necessary B. desired B. cleaner B. cigarettes B. warned B. last B. fair | C. customers C. wisdom C. heavy C. hardly C. closed C. anywhere C. swallowed C. off C. courageous C. sweet C. should C. pick up C. before C. reliable C. expected C. cleverer C. drinks C. ordered C. best C. small | D. passengers D. privilege D. swift D. obviously D. broke D. everywhere D. dropped D. by D. hungry D. unique D. need D. hand in D. since D. important D. admired D. quicker D. food D. persuaded D. worst D. full |