The LISA spectrometer David O’Donnell STFC Daresbury Laboratory.

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The LISA spectrometer David O’Donnell STFC Daresbury Laboratory

Transcript of 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