title: Development of a fast scintillator based beam phase measurement system for compact superconducting cyclotrons.
abstract: In an isochronous cyclotron, measurements of central phase of the ion beam with respect to rf and the phase width provide a way to tune the cyclotron for maximum energy gain per turn and efficient extraction. We report here the development of a phase measurement system and the measurements carried out at the Variable Energy Cyclotron Centre's (VECC's) K = 500 superconducting cyclotron. The technique comprises detecting prompt γ-rays resulting from the interaction of cyclotron ion beam with an aluminium target mounted on a radial probe in coincidence with cyclotron rf. An assembly comprising a fast scintillator and a liquid light-guide inserted inside the cyclotron was used to detect the γ-rays and to transfer the light signal outside the cyclotron where a matching photo-multiplier tube was used for light to electrical signal conversion. The typical beam intensity for this measurement was a few times 10(11) pps.
authors.affiliation: Variable Energy Cyclotron Centre, 1/AF Bidhannagar, Kolkata 700064, India.
authors.forename: Tanushyam
authors.initials: T
authors.lastname: Bhattacharjee
authors.forename: Malay
authors.initials: M
authors.lastname: Kanti Dey
authors.forename: Partha
authors.initials: P
authors.lastname: Dhara
authors.forename: Suvodeep
authors.initials: S
authors.lastname: Roy
authors.forename: Jayanta
authors.initials: J
authors.lastname: Debnath
authors.forename: Rajendra
authors.initials: R
authors.lastname: Balakrishna Bhole
authors.forename: Atanu
authors.initials: A
authors.lastname: Dutta
authors.forename: Jedidiah
authors.initials: J
authors.lastname: Pradhan
authors.forename: Sarbajit
authors.initials: S
authors.lastname: Pal
authors.forename: Gautam
authors.initials: G
authors.lastname: Pal
authors.forename: Amitava
authors.initials: A
authors.lastname: Roy
authors.forename: Alok
authors.initials: A
authors.lastname: Chakrabarti