Author: Debnath, J.
Paper Title Page
MO1PB03 Current Status of the Superconducting Cyclotron Project at Kolkata 11
  • J. Debnath, A. Chakrabarti, M.K. Dey
    VECC, Kolkata, India
  The commissioning of Kolkata superconducting cyclotron with internal ion beam had been reported in the last cyclotron conference. At that time, there was gradual beam loss due to poor vacuum. After installing a higher capacity liquid helium plant the cryo-panels were made functional leading to a substantial increase in the beam intensity. It was hoped that higher beam intensity would help in extraction of a measurable fraction of the beam, but that did not happen. Detailed investigation of beam behavior with the help of three beam probes, installed temporarily at three sectors, revealed that the beam goes highly off-centered while passing through the resonance zone. A plastic scintillator based phase probe was mounted on the radial probe and beam phase was measured accurately. It was quite clear that large amount of field imperfection was prohibiting the beam to be extracted. So magnetic field measurement has been started again and considerable amount of harmonic and average field errors have been found. In this paper we report the important developments since 2010.  
slides icon Slides MO1PB03 [13.028 MB]  
WEPPT011 Measurement of Radial Oscillation and Phase of Accelerating Beam in Kolkata Superconducting Cyclotron 344
  • J. Pradhan, A. Agarwal, U. Bhunia, A. Chakrabarti, J. Debnath, M.K. Dey, A. Dutta, Z.A. Naser, S. Paul, V. Singh
    VECC, Kolkata, India
  This paper describes various measurements performed on the beam behavior with the help of the main probe and the differential probe to have a clear insight of the accelerating beam and the difficulties of beam -extraction process in the K500 superconducting cyclotron at Kolkata. Beam shadow measurements with three probes at three sectors were done to get the information of beam-centering and radial oscillations. The radial oscillation amplitude is estimated from the measurements. A differential probe was used to measure the turn separation and its modulation due to radial oscillation. With the help of magnetic field detuning method, the beam phase history was also measured.  
WEPPT012 Beam Dynamics in Presence of Imperfection Fields Near the Extraction Zone of Kolkata Superconducting Cyclotron 347
  • J. Debnath, U. Bhunia, A. Chakrabarti, M.K. Dey, A. Dutta, Z.A. Naser, S. Paul, J. Pradhan, V. Singh
    VECC, Kolkata, India
  Funding: VECC, DAE
The superconducting cyclotron at Kolkata has accelerated the ion beams up to the extraction radius producing neutrons via nuclear reactions. After that the beam extraction process has been tried exhaustively. But rigorous beam extraction trials indicate towards some kind of error field, which was not possible to balance with the trim coil operated in harmonic-coil mode. It is found that the beam is being off-centered by a large amount after crossing the resonance zone and it is not reaching the extraction radius in proper path. This paper will be emphasizing the effect of various kind of error field on the beam. However, the magnetic field is being measured again to know the exact distribution of the field.