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OverviewOverview

Physics of Proton-rich Nuclei in the UK

Mike Bentley (Univ. of York, UK)

Physics of Proton-rich Nuclei in the UK

Mike Bentley (Univ. of York, UK)

Outline:Recent Highlights:• RISING physics at GSI• Isospin studies at MSU• Shapes and Symmetries (JYFL)Prospects:• Short term developments• Future facilities

Outline:Recent Highlights:• RISING physics at GSI• Isospin studies at MSU• Shapes and Symmetries (JYFL)Prospects:• Short term developments• Future facilities

• How well does Isospin symmetry hold as A or Tz is increased?

• Limits of nuclear existence

• rp-process near the drip line

• Evolution of nuclear shapes

• n-p pairing

OverviewOverview

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Current facilities (not exhasutive)

JYFL – Jurogam + RITU + GREAT (recoil decay tagging)

ANL – Gammasphere + FMA (recoil tagging)

GSI – RISING stopped beam campaign (decay spectroscopy)

REX-ISOLDE – Miniball (Coulex of exotic beams)

OverviewOverview

RISING

Rare Isotopic Spectroscopic

INvestigations @ GSI =

15 x Cluster germaniums for

(the most) exotic gamma-ray

spectroscopy

Example: RISING at GSIExample: RISING at GSI

• Chemically independent production mechanism for secondary radioactive beams. • Time of flight from production to stopper ~x00ns.• Some ions transmitted in metastable states.

Fragment Separator (FRS) Focal Pane ID Stopped RISING

Example: RISING at GSIExample: RISING at GSI

Example: RISING at GSIExample: RISING at GSI

Example: RISING at GSIExample: RISING at GSI

Example: RISING at GSIExample: RISING at GSI

A.B. Garnsworthy et al., Phys. Lett. B660, 326 (2008)A.B. Garnsworthy et al., Phys. Lett. B660, 326 (2008)

Example: RISING at GSIExample: RISING at GSI

Texas A&M Cyclotron Institute: May 2007 10

NSCL Experiment #5117, March 2007

0.5 -1.0 × 106 pps (70% 56Ni)

188 mg/cm2 Be

10pnA 58Ni

600 mg/cm2 Be target

S800 Spectrograph

Example: Fragmentation at MSUExample: Fragmentation at MSU

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S800 – Fragment ID

Z

A/Q

Drip line

J.R. Brown et al. (YORK) in prep (2008)J.R. Brown et al. (YORK) in prep (2008)

Example: Fragmentation at MSUExample: Fragmentation at MSU

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First spectrsocopy of N=Z-3 nuclei

above 33Ar

53Mn

53Ni

49V

49Fe

J.R. Brown et al. (YORK) in prep (2008)J.R. Brown et al. (YORK) in prep (2008)Example: Fragmentation at MSUExample: Fragmentation at MSU

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J.R. Brown et al. (YORK) in prep (2008)J.R. Brown et al. (YORK) in prep (2008)

Observed A=54 MEDExpected MED (2 holes)

Decreasing overlap of two nucleons coupled to increasing spin J

Charge Symmetry Breaking – spin dependence (J=2 Anomaly)

Example: Fragmentation at MSUExample: Fragmentation at MSU

Recoil decay tagging at JyvaskylaRecoil decay tagging at JyvaskylaJUROGAM

RITUGas-filled recoil separator

Transmission 20-50 %

GREATFocal plane spectrometer

TDRTotal Data ReadoutTriggerless data acquisition systemwith 10 ns time stamping

Example: Recoil Decay Tagging at JyvaskylaExample: Recoil Decay Tagging at Jyvaskyla

Recoil-β-tagging using GREAT

Useful for odd-odd N=Z, A>60-100 and N<Z nuclei in this region. Fermi super allowed decays, ~10’s of ms half lives, ~10 MeV end point energies

A.N. Steer et al, NIM A 565, 630(2006)

Example: Recoil Decay Tagging at JyvaskylaExample: Recoil Decay Tagging at Jyvaskyla

B S Nara Singh et al, PRC 75 061301(R) 200778Y Results

T1/2 = 47 (5) ms74Rb

78Y

Example: Recoil Decay Tagging at JyvaskylaExample: Recoil Decay Tagging at Jyvaskyla

Neutron-proton pairing effects ?

Shape-changing effects ?

Example: Recoil Decay Tagging at JyvaskylaExample: Recoil Decay Tagging at Jyvaskyla

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Next in-beam campaign at GSI...PRESPEC – spokesperson MAB

2010-2011

ADVERTADVERT

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Future facilities (not exhasutive)

HIE-ISOLDE

FAIR – HISPEC (in-beam) and DESPEC (decay spectroscopy)

SPIRAL2 – in-beam reactions with exotic ions, or use of high-intensity LINAC beams

Future facilities for p-rich nucleiFuture facilities for p-rich nuclei

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