STARS ( & STRIPES?) @ Gammasphere

C.W.B. and Mitch Allmond (for the LLNL/LBNL/Richmond Collaboration)

STARS = Silicon Telescope Array for Reaction Studies

STARS-LiBerACEat the 88-Inch at LBNL

d Beam @

21&29 MeV

235U

E E1 E2

Clover (6 in all)

p

Fission-E

Si Det

fis

Si Det

.5mm 1mm1mm.14mm

+12C**

**400 g/cm2 target with 12C backing

“raytrace”

48 Rings 16 Sectors

STARS and Liberace

Used at LBNL for a variety of reaction / structure experiments including the surrogate reaction program

STARS: Charge particles and fission

About 20% geometric efficiency

Liberace: 6 Clover detectors

About 1% gamma efficiency

Particle ID:

Banana gate on p

p-

p-f235U(d,pf ) 236U

235U(d,p ) 236U

Light massfragment.

Heavy massfragment

Relative Energy

235U(d,p)236U as surrogate for 235U + n

Internal Ratio Result for 235U(n,)

ENDF

J.M. Allmond et al. Phys. Rev. C79, 054610 (2009).

particle – gamma – gamma

2 105 events in matrix

Summary

Count Rate: Liberace ~ 1 % vs. Gammasphere ~9%

Particle – gamma Increase by factor of 9

Particle-gamma-gamma increase by factor of 80!

STARS: (& STRIPES ???)

Chamber exists which has run at Gammasphere in the past!

96 channel feedthrough (3 S2 detectors)

Preamps and analog electronics available up to ADC (possibly digital also?)

Interest and effort available from Richmond (CWB, Mitch Allmond) and Livermore (Jason Burke, Lee Bernstein) in bringing STARS to

Gammasphere