061116 prismws itahashi

Slide1: 

Injection study for 6-sector PRISM FFAG by using pulsed alpha particles Takahisa Itahashi, Yousuke Takubo, Chihiro Ohmori, Akira Sato,and Yoshitaka Kuno Department of Physics, Graduate School of Science, Osaka Univ. 1-1 Machikaneyama, Toyonaka-shi, Osaka 560-0043, Japan

Contents: 

Contents Procedure for demonstration of PRISM by alpha particle injection into a Test RF-cavity Test RF-cavity application for high gradient & saw-tooth voltage – It will be suitable and preliminary device for injection and detection tests of alpha particles Injection study of 6-sector accumulator ring for PRISM with alpha particle

What should be done for demonstration of PRISM ? Proof of principle of quarter-turn rotation in phase space for muons with a short lifetime : 

What should be done for demonstration of PRISM ? Proof of principle of quarter-turn rotation in phase space for muons with a short lifetime Huge momentum acceptance : +/- 20% Limited time for phase rotation : 2.2 ms Inj. & Ext. loss : as little as possible Low background at detector : circular structure for accumulator, not directed to PRIME target Phase rotation for narrow energy spread of m-on = PRISM

Proof of principle of quarter-turn rotation in phase space for muons with a short lifetime : 

Proof of principle of quarter-turn rotation in phase space for muons with a short lifetime Huge momentum spread : +/- 20% In a limited time for phase rotation : 2.2 ms Inj. & Ext. loss : as a little as possible Low background at detector : circular structure for accumulator, not directed to target = PRISM

The reason for design of 6-sector accumulator FFAG-ring: 

The reason for design of 6-sector accumulator FFAG-ring For proof of principle PRISM -2.2ms For limited budget – magnets 3+2+(1) For limited time for project in 2002-2007 For alpha particle injection- the same ligidity as m-on For single acc. test-cavity For simple injection, inflector, pulsing, For measurement energy and TOF- proof of principle For limited acceptance- small vacuum chamber

6-sector FFAG accumulator ring with slant magnets manufactured for 10-sector PRISM-FFAG : 

6-sector FFAG accumulator ring with slant magnets manufactured for 10-sector PRISM-FFAG

Are there any solutions for accumulator ring by using 6-PRISM magnets ?: 

Are there any solutions for accumulator ring by using 6-PRISM magnets ? Scaling type FFAG Radial sector and slant magnets Proper tune diagrams Existing single cavity Enough radial vertical acceptance Cost minimum for demonstration

Momentum dependence of vertical and horizontal tune of 6-sector accumulator ring : 

Momentum dependence of vertical and horizontal tune of 6-sector accumulator ring

Tune diagrams for 6-sector FFAG-RING: 

Tune diagrams for 6-sector FFAG-RING

Horizontal and vertical acceptance: 

Horizontal and vertical acceptance

Proof of principle for PRISM : 

Proof of principle for PRISM Single cavity with a high gradient sinusoidal with a high gradient saw-tooth Radial sector 6 magnets One single gap cavity with MA-core (no-half-cut) operating freq ~ 1 MHz Power amplifier with wide freq. range Vacuum chamber Alpha particle injection instead of m-on Energy and TOF measurement

Test cavity: 

Test cavity

Alpha particles accelerated with an AVF cyclotron from 5.4 MeVto 30 MeV and extracted. Alpha source is located at the proper radius. : 

Alpha particles accelerated with an AVF cyclotron from 5.4 MeV to 30 MeV and extracted. Alpha source is located at the proper radius.

Pulsing system, performance for ALPS: 

Pulsing system, performance for ALPS Pulsing frequency: 5.0MHz Pulse width : 20~30 nsec Duty factor : 0.001 Pulsing voltage: DC + RF ~1.0 KV Pulsing electrode, length: 30 cm Pulsing electrode, gap: 25 mm

TOF measuring apparatus for an acceleration test cavity : 

TOF measuring apparatus for an acceleration test cavity

Alpha particle source ALPS: 

Alpha particle source ALPS

6-sector FFAG accumulator ring with slant magnets manufactured for 10-sector PRISM-FFAG ring : 

6-sector FFAG accumulator ring with slant magnets manufactured for 10-sector PRISM-FFAG ring

Alpha particle injection : 

Alpha particle injection Vertical injection Limited space in straight section and limited room of vacuum chamber to install the guiding electrodes Limited space for kicker electrode Cylindrical + quadrupole guiding for alpha particles Q-triplet(permanent)+ cylindrical + quasi-quad

Power supply for electric kicker : 

Power supply for electric kicker Out put voltage : - 10 kVp Pulse width : > 0.1 mS (FWHM) Repetition rate : 5 KHz (5kpps) Droop : < 3 % Rise time : 25 nsec (design) Fall time : 50 nsec (design) Flat : 60 nsec EIMAC (CPI) Assumed capacity is 10pF or more

Injection study by using an electric kicker for alpha particle injection at one straight section : 

Injection study by using an electric kicker for alpha particle injection at one straight section Particle tracking simulation for a quarter turn phase rotation with ALPS Vacuum chamber design for minimum aperture Straight section design for particle injection with a kicker Particle transport calculation for electric guiding fields Detector design and a DAQ-system Rf-operation with high voltage 1-turn and 2-turn ------ 6-turn TOF measurements

Demonstration for PRISM Schedule: 

Demonstration for PRISM Schedule ALPS for a test cavity --- 2006/Dec. TOF measurement --- 2007/Feb. Design of power supply for injection kicker--2007/ May Design of vacuum chamber ---2007/Mar. RF power supply –improvement –2007/Jun. Cavity+RF power supply– improvement 2007/Jun. Sector magnet --- accumulator ring ??? Measurement --- 2008/Jan.

Summary: 

Summary Field measurement for three PRISM-FFAG magnets has been completed Rf-cavity test for saw tooth wave form will be tried soon Alpha particle injection for cavity and sector magnet will be started. This is an appropriate preparation for construction of PRISM-FFAG POP for PRISM will be started in 6-sector ring, although it has not so large acceptance

Slides from 30-38 are something for help: 

Slides from 30-38 are something for help

Transported and injected muon beam: 

Transported and injected muon beam Dispersion matched at injection Central momentum : 68 MeV/c Requi = 6.5 m Momentum spread : +/- 20 % Beam intensity 1011 ~ 1012 / sec Aperture : 30 cm (v) x 100 cm (h)

Requirements for diagnostics in FFAG-PRISM : 

Requirements for diagnostics in FFAG-PRISM Comparison with anti-proton production Similar facilities as PRISM was ? at CERN and will be AD-project at J-PARC(ref. E.Widman). AD : 200 pi mm mrad and dp/p = 6 % : stable : proton beam of capture momentum is very helpful for tuning : various cooling techniques are helpful for storage Comparison with radio-active ion beam at RIBF MUSES : +/- 10 mrad and dp/p = 2.5 % : lifetimes of order of 1 microsec. : cooling and high luminosity are considered for collision

Sci-Fiber: 

Sci-Fiber Sci-Fiber could be applied for beam diagnostics in PRISM-FFAG Dr. M. Yoshida-san would have a short comment for this issue Mr. Takayanagi-san would like to develop the device next year.

Position sensitive solid state counter (energy and TOF): 

Position sensitive solid state counter (energy and TOF) 50 mm x 50 mm silicon strip solid state counter for energy measurement rf-particle TOF measurement Two dimensional measurement between position and energy

Bunch rotation techniques: 

Bunch rotation techniques