Author: Mandal, A.
Paper Title Page
MOPC088 Bead-pull Measurement using Phase-Shift Technique in Multi-cell Elliptical Cavity 280
  • S. Ghosh, A. Mandal, S. Seth, S.S. Som
    DAE/VECC, Calcutta, India
  The project on the development of high-beta multi-cell elliptical shape superconducting rf linac cavity at around 704 MHz has been funded at VECC, Kolkata, India. A full-scale copper prototype cavity has been designed and fabricated. There are 5 distinct modes exist in the cavity and the accelerating mode is pi-mode in which each cell operates at same frequency with phase difference of 180 degrees between two neighboring cells. A fully automated bead-pull measurement setup has been developed for analyzing these modes and field profile distribution at different modes in such type of linac cavity. A special measurement method inside the cavity using phase-shift technique is proposed in this paper, which describes the development of mechanical setup comprising pulleys and stepper motor–gear arrangement, PC-based control system for precise movement of bead using stepper motor, measurement using VNA, development of software for data acquisition & automation and measurement results for the 5-cell copper prototype cavity.  
WEPC011 Ion Optical Design of the Low Energy Ion Beam Facility at IUAC 2025
  • A. Mandal, D. Kanjilal, S. Kumar, G. Rodrigues
    IUAC, New Delhi, India
  A Low Energy Ion Beam Facility (LEIBF) using fully permanent magnet ECR ion source (Nanogan) has been installed at Inter University Accelerator Centre (IUAC), New Delhi for fundamental research on Atomic and Molecular Physics, and Material Science. The accelerator consists of an ECR ion source, 400 kV accelerating column and an analyzing-cum switching magnet with three beam ports at 75, 90 and 105 degrees. The complete ion optics from ECR ion source to the target has been simulated using TRANSPORT* and GICOSY** ion optics codes. The ions from the ECR source are typically extracted at 15 kV which are further accelerated by 400 kV accelerating column. The analyzing cum switching magnet has been designed to analyze different beams and to switch in a particular beam line. It is a H shaped dipole magnet having pole gap of 65 mm, maximum magnetic field of 1.5 T and radius of 529 mm for 90 degree bend. The entrance and exit edge angles for three beam lines have been optimized to obtain double focus in all beam lines. The beam is further transported to target locations using electrostatic quadrupole triplet. The details of ion optics will be presented in the paper.
* K.L. Brown, D.C. Carey, Ch. Iselin and F. Rothacker: Transport, See yellow reports CERN 73-16 (1973) & CERN 80-04 (1980).
** H.Weick, GICOSY homepage,