Coordinatori
Beams Interactions: S1.1
- Stefano Redaelli
Beams Interactions: S1.2
- Vincenzo Guidi (INFN)
A new high-quality positron 530 MeV beam has been installed at the Institute for Nuclear Physics of the University of Mainz using the features of the MAMI accelerator. Positrons are created by pair conversion of bremsstrahlung, produced by a focused 855 MeV electron beam of MAMI in a 10 µm thick tungsten self converter target, and energy selected by an outside open electron beam-line bending...
Using a 530 MeV positron beam from the Mainz Microtron MAMI and a bent silicon crystal, we successfully manipulated positron trajectories through planar channeling and volume reflection. This experiment revealed detailed structures in the angular distribution of channeled charged particles within bent crystal planes. Our findings align with simulations, enhancing our understanding of...
The work considers the mechanism of self-controlled autocollimation of a beam of positive ions during their channeling in crystals, which can lead to a significant reduction in the angular dispersion of the ions beam. The autocollimation process is associated with elastic ion scattering and stepwise transfer of the transverse energy E_\perp of a channeled ion to groups N \approx \Lambda / 2...
An analytical model for the volume capture of high-energy positive particles into planar (111) channels of a silicon single crystal is proposed. Under the assumption that the cause of particle capture is multiple scattering, the capture probability is found. Channeling of trapped particles is also considered. Comparison of calculations with experiment is performed. Results of the study will...
In order to perform full simulations of crystal-based extraction from an accelerator, a combination of simulation codes for beam dynamics in an accelerator and channeling physics in crystals is required. Our solution exploits the Beam Delivery Simulation (BDSIM) [1], an extensive library that contains thick lens accelerator tracking routines and a wide variety of accelerator components and...
The efficiency of planar channeling for positive particles is limited by nuclear scattering when particles approach too close to the nuclei within the atomic planes. To mitigate this effect, a solution was proposed in 2007 [1], involving the creation of an optimized interruption in the crystal lattice at a strategic position before nuclear dechanneling can occur. Implementing this solution...
Bent crystals, through channeling effects, can induce coherent deflection of charged particles, making them invaluable tools for controlling particle beams. This research focuses on the fabrication, of bent crystals tailored for spin precession studies at the LHC.
Bent crystal have been widely used to deflect high energy particles in the last decades and the precise knowledge of their properties has been crucial for their deployment in particle accelerator complex. Based on a time-reversal approach to the channeling effect, the UA9 collaboration is investigating the possibility to merge two particle beam impinging with specific angles on a bent crystal....
It is shown that if the screening function of an atomic potential may be described within the Thomas-Fermi approximation, the corresponding continuous potential for planar channeling to a good accuracy reduces to a truncated Coulomb potential. The sum of two displaced Coulomb potentials also accurately approximates thermal continuous potentials for (110) Si, Ge, W and (111) Ge oriented...
