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Title: Beam Profile Measurement in MTA Beam Line for High Pressure RF Cavity Beam Test

Abstract

Recent High Pressure RF (HPRF) cavity experiment at MuCool Test Area (MTA) has used 400 MeV Linac proton beam to study the beam loading effect. When the energetic proton beam passes through the cavity, it ionizes the inside gas and produces the electrons. These electrons consume RF power inside the cavity. Number of electrons produced per cm inside the cavity (at 950 psi Hydrogen gas) per incident proton is {approx} 1200. The measurement of beam position and profile are necessary. MTA is flammable gas (Hydrogen) hazard zone so we have developed a passive beam diagnostic instrument using Chromox-6 scintillation screen and CCD camera. This paper presents quantitative information about beam position and beam profile. Neutral density filter was used to avoid saturation of CCD camera. Image data is filtered and fitted with Gaussian function to compute the beam size. The beam profile obtained from scintillation screen shall be compared with multi-wire beam profile.

Authors:
; ; ; ; ; ; ; ; ; ; ;
Publication Date:
Research Org.:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1048448
Report Number(s):
FERMILAB-CONF-12-149-APC
TRN: US1204217
DOE Contract Number:
AC02-07CH11359
Resource Type:
Conference
Resource Relation:
Journal Name: Conf.Proc.C1205201:948-950,2012; Conference: Presented at the 3rd International Particle Accelerator Conference (IPAC-2012), New Orleans, Louisiana, 20-25 May 2012
Country of Publication:
United States
Language:
English
Subject:
43 PARTICLE ACCELERATORS; 08 HYDROGEN; ACCELERATORS; BEAM POSITION; BEAM PROFILES; ELECTRONS; HYDROGEN; LINEAR ACCELERATORS; PROTON BEAMS; PROTONS; SATURATION; SCINTILLATIONS; SCREENS; Accelerators

Citation Formats

Jana, M.R., Bross, A., Chung, M., Greer, S., Johnstone, C., Kobilarcik, T., Koizumi, G., Leonova, M., Moretti, A., Popovic, M., Schwartz, T., and /Fermilab /IIT, Chicago /PDT, Torino. Beam Profile Measurement in MTA Beam Line for High Pressure RF Cavity Beam Test. United States: N. p., 2012. Web.
Jana, M.R., Bross, A., Chung, M., Greer, S., Johnstone, C., Kobilarcik, T., Koizumi, G., Leonova, M., Moretti, A., Popovic, M., Schwartz, T., & /Fermilab /IIT, Chicago /PDT, Torino. Beam Profile Measurement in MTA Beam Line for High Pressure RF Cavity Beam Test. United States.
Jana, M.R., Bross, A., Chung, M., Greer, S., Johnstone, C., Kobilarcik, T., Koizumi, G., Leonova, M., Moretti, A., Popovic, M., Schwartz, T., and /Fermilab /IIT, Chicago /PDT, Torino. Tue . "Beam Profile Measurement in MTA Beam Line for High Pressure RF Cavity Beam Test". United States. doi:.
@article{osti_1048448,
title = {Beam Profile Measurement in MTA Beam Line for High Pressure RF Cavity Beam Test},
author = {Jana, M.R. and Bross, A. and Chung, M. and Greer, S. and Johnstone, C. and Kobilarcik, T. and Koizumi, G. and Leonova, M. and Moretti, A. and Popovic, M. and Schwartz, T. and /Fermilab /IIT, Chicago /PDT, Torino},
abstractNote = {Recent High Pressure RF (HPRF) cavity experiment at MuCool Test Area (MTA) has used 400 MeV Linac proton beam to study the beam loading effect. When the energetic proton beam passes through the cavity, it ionizes the inside gas and produces the electrons. These electrons consume RF power inside the cavity. Number of electrons produced per cm inside the cavity (at 950 psi Hydrogen gas) per incident proton is {approx} 1200. The measurement of beam position and profile are necessary. MTA is flammable gas (Hydrogen) hazard zone so we have developed a passive beam diagnostic instrument using Chromox-6 scintillation screen and CCD camera. This paper presents quantitative information about beam position and beam profile. Neutral density filter was used to avoid saturation of CCD camera. Image data is filtered and fitted with Gaussian function to compute the beam size. The beam profile obtained from scintillation screen shall be compared with multi-wire beam profile.},
doi = {},
journal = {Conf.Proc.C1205201:948-950,2012},
number = ,
volume = ,
place = {United States},
year = {Tue May 15 00:00:00 EDT 2012},
month = {Tue May 15 00:00:00 EDT 2012}
}

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  • In order to demonstrate the feasibility of high pressure hydrogen gas filled RF (HPRF) cavities for muon ionization cooling, an HPRF cavity must be tested with a high intensity charged beam. When an HPRF cavity is irradiated with an intense beam each incident particle generates about 1000 electrons and ions per cubic centimeter in a high pressure cavity via ionization. These ionization electrons are influenced by the RF field and the RF quality factor goes down. This Q factor reduction will be a problem with a multi bunch beam, e.g., a muon beam for a muon collider consists of amore » 12 to 20 bunch train beam with 5 ns timing gap. Thus, the RF field must recover in few nano seconds. We propose to use a 400 MeV proton beam in the MTA and measure a beam loading effect in the HPRF cavity and study the recovery mechanism of the RF field.« less
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