title: Performance of the beam chamber vacuum system of K = 500 cyclotron at Variable Energy Cyclotron Centre Kolkata.
abstract: The beam chamber of Variable Energy Cyclotron Centre, Kolkata's K = 500 superconducting cyclotron is pumped by liquid helium cooled cryopanel with liquid nitrogen cooled radiation shield. Performance of the vacuum system was evaluated by cooling the cryopanel assembly with liquid nitrogen and liquid helium. Direct measurement of beam chamber pressure is quite difficult because of space restrictions and the presence of high magnetic field. Pressure gauges were placed away from the beam chamber. The beam chamber pressure was evaluated using a Monte Carlo simulation software for vacuum system and compared with measurements. The details of the vacuum system, measurements, and estimation of pressure of the beam chamber are described in this paper.
authors.affiliation: Variable Energy Cyclotron Centre, I/AF Bidhannagar, Kolkata 700064, India.
authors.forename: Gautam
authors.initials: G
authors.lastname: Pal
authors.affiliation: Variable Energy Cyclotron Centre, I/AF Bidhannagar, Kolkata 700064, India.
authors.forename: Anjan
authors.initials: A
authors.lastname: DuttaGupta
authors.affiliation: Variable Energy Cyclotron Centre, I/AF Bidhannagar, Kolkata 700064, India.
authors.forename: Alok
authors.initials: A
authors.lastname: Chakrabarti