Laser stripping for 1.3 GeV H beam at the SNS

Gorlov, T.*; Aleksandrov, A.*; Cousineau, S.*; Liu, Y.*; Oguz, A. R.*; Kay, M.*; Saha, P. K.

Proceedings of the 2022 North American Particle Accelerator Conference (NAPAC 2022) (Internet), p.702 - 704, 2022/08

https://doi.org/10.18429/JACoW-NAPAC2022-WEPA33

The conventional method of H charge-exchange injection by using a solid stripper foil has serious drawbacks such as, a short foil lifetime, unexpected failure and moreover a high residual radiation due to uncontrolled foil scattering beam losses at high-intensity operation. To overcome all those issues, an H stripping by using only lasers or by laser assisted are being extensively studied at J-PARC and the Spallation Neutron Source (SNS) at Oak Ridge, USA, respectively. However, a reduction of the laser power to realize the laser stripping is a common issue at both labs. In this research, different schemes and methods of laser stripping, especially for an effective excitation of the ground state hydrogen atom are considered. Among all methods the most realistic and practical scheme seems to be the sequential excitation scheme by using two types of laser. In this case, a laser power can be reduced to 1/25 as compared to a single step excitation. Due to a lower H energy, a deep UV laser is used at J-PARC. Such a reduction of the laser power is further useful for a realistic implementation.