The LISA spectrometer David O’Donnell STFC Daresbury Laboratory.

The LISA spectrometer

David O’DonnellSTFC Daresbury Laboratory

What is LISA?

Light Ion Spectrometer Array

Array of silicon detectors

Design based on TIARA

-Si array for transfer reactions at GANIL

Designed to detect charged particles at the target position of the

Jyvaskyla JUROGAM-RITU-GREAT apparatus

Why use LISA?

...but it has its limitations

Decay by proton emission – too fast for standard RDT

Use LISA to detect fast proton decays

ToF > 0.5 s

Recoil-decay tagging has proven to be extremely successful...

Why use LISA?

...but it has its limitations

Decay by proton emission – too fast for standard RDT

Use LISA to detect fast proton decays

ToF > 0.5 s

Recoil-decay tagging has proven to be extremely successful...

Why use LISA?

...but it has its limitations

Decay by proton emission – too fast for standard RDT

Use LISA to detect fast proton decays

ToF > 0.5 s

Recoil-decay tagging has proven to be extremely successful...

Why use LISA?

...but it has its limitations

Decay by proton emission – too fast for standard RDT

Use LISA to detect fast proton decays

ToF > 0.5 s

Recoil-decay tagging has proven to be extremely successful...

Why use LISA?

...but it has its limitations

Decay by proton emission – too fast for standard RDT

Use LISA to detect fast proton decays

ToF > 0.5 s

Recoil-decay tagging has proven to be extremely successful...

p

Why use LISA?

...but it has its limitations

Decay by proton emission – too fast for standard RDT

Use LISA to detect fast proton decays

Recoil-decay tagging has proven to be extremely successful...

Why use LISA?

Detection of prompt charged particles emitted from deformed high-lying states

Rudolph et al., PRL 80 (1998) 3018

Also as a veto to select weak xn evaporation channels following fusion-evaporation reactions

LISA: a few details

Novel target changing mechanism: two rotating

targets, an alpha source and quartz glower

Two octagonal Si barrels and two Si annular detectors:

≈ 80% of 4

Molybdenum foils to shield from scattered heavy-ions

LISA: a few details

Novel target changing mechanism: two rotating

targets, an alpha source and quartz glower

Two octagonal Si barrels and two Si annular detectors:

≈ 80% of 4

Molybdenum foils to shield from scattered heavy-ions

LISA: a few details

Novel target changing mechanism: two rotating

targets, an alpha source and quartz glower

Two octagonal Si barrels and two Si annular detectors:

≈ 80% of 4

Molybdenum foils to shield from scattered heavy-ions

LISA: a few details

Novel target changing mechanism: two rotating

targets, an source and quartz glower

Two octagonal Si barrels and two Si annular detectors:

≈ 80% of 4

Molybdenum foils to shield from scattered heavy-ions

Commissioning experiment @ JYFL

November 2009

58Ni (300 MeV) + 106Cd -> 164Os *

LISA – JUROGAM II – RITU – GREAT

Limited electronics set-up: two inner barrel detectors, two outer barrel detectors and one

annular detector

Results of commissioning

Simulation

Future of LISA• Plan to repeat 58Ni + 106Cd

commissioning measurement with full array– study 159Re (p4n)

• Other intertesting cases include 169Au

Future of LISA• Identify candidates for prompt

proton emission outside of Z~28, N~28– Possibly neutron-deficient Te isotopes?

• Use in “double--tagging” (D.G. Jenkins et al. proposal to JYFL)– Si detectors replaced with plastic

scintillator to provide larger coverage– Study astrophysically important nuclei

beyond N=Z line (66Se)

• Any other ideas?

LISA collaborationSTFC Daresbury: R. Griffiths, M. Labiche, P. Morrall, D. O’Donnell, J. Simpson and J. Strachan.

University of Liverpool: R.J. Carroll, D.T. Joss, R.D. Page, J. Thornhill and D. Wells.

University of Jyväskylä: T. Grahn, P.T. Greenlees, K. Hauschild, A. Herzan, U. Jakobsson, P.M. Jones, R. Julin, S. Juutinen,S. Ketelhut, M. Leino, A. Lopez-Martens, P. Nieminen, P. Peura, P. Rahkila, S. Rinta-Antila, P. Ruotsalainen, M. Sandzelius, J. Sarén, C. Scholey, J. Sorri and J. Uusitalo.

University of the West of Scotland: J.F. Smith