1. What's the merit of FET compared with transistor?
FET is powered by E field, transistor by real current. So transistor needs more power. And FET can be produced in smaller size.
2. Can we simulate MOSFET under bias?
It doesn't mean too much. But we can do it if necessary.
1. What causes beam loss?
One is for bunch out of control crashing into beampipe; the other is for particles in beampipe(but they don't make vacuum out of range) crashing with e+e-.
2. LHC interval is: 25ns(40MHz).