Salvador12
Full Member level 4
Hi I am reading about klystrons for some time, Now I understand the bunching and velocity modulation due to the E field between the cavity plates where the electrons pass through the hole in the middle,
here is the thing that I think i'm still missing,
so the electrons come out of a electron gun and are accelerated by a large DC potential , say 450kV for example, the beam itself has a current of say 450A. Now as this current passes the first cavity some parts of the beam feel an opposing E field while some feel an accelerating one, now the electrons as they travel along the drift tube bunch up as these bunches travel through the output cavity they induce E fields between the cavity plates , which I assume are strong , probably on the order of kV/cm, then further I assume that this E field charges up the cavity plates and as they charge and discharge through the cavity torus it creates a current in the torus which sets up a toroidal shaped B field within the torus,
1)so the coax or waveguide output is taken from a single loop located within the torus structure , does this mean that the output from a klystron is coupled via the B field inside the torus?
2)Also are there any estimates as to how strong this toroidal B field is for a given klystron?
3)And another question, I read on some papers that the E field at the output cavity windows (where waveguide is attached) can reach strengths up to say 60MV/cm, I cannot understand how can one have such a strong E field given the klystron beam accelerating voltage is 610kV?
https://www.osti.gov/servlets/purl/1110653
see page 17
here is the thing that I think i'm still missing,
so the electrons come out of a electron gun and are accelerated by a large DC potential , say 450kV for example, the beam itself has a current of say 450A. Now as this current passes the first cavity some parts of the beam feel an opposing E field while some feel an accelerating one, now the electrons as they travel along the drift tube bunch up as these bunches travel through the output cavity they induce E fields between the cavity plates , which I assume are strong , probably on the order of kV/cm, then further I assume that this E field charges up the cavity plates and as they charge and discharge through the cavity torus it creates a current in the torus which sets up a toroidal shaped B field within the torus,
1)so the coax or waveguide output is taken from a single loop located within the torus structure , does this mean that the output from a klystron is coupled via the B field inside the torus?
2)Also are there any estimates as to how strong this toroidal B field is for a given klystron?
3)And another question, I read on some papers that the E field at the output cavity windows (where waveguide is attached) can reach strengths up to say 60MV/cm, I cannot understand how can one have such a strong E field given the klystron beam accelerating voltage is 610kV?
https://www.osti.gov/servlets/purl/1110653
see page 17