Nuclear structure around 100Sn

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Nuclear structure around 100Sn

• Darek Seweryniak, ANL

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Doubly-magic nuclei
208Pb
100Sn
48Ni
56Ni
132Sn
16O
78Ni
40,48Ca
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100Sn physics
Z
super allowed a-decay
rp process end point
p/2p decay
100Sn
Doubly-magic
Self-conjugate
spe
GT b-decay
n-n interactions
N
bp
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Heavy-ion fusion-evaporation reactions

• 46Ti(58Ni,4n)100Sn (EB220MeV)
• s5 nb (103Sn-5mb,102Sn-500nb,101Sn-50nb,
  100Sn-5nb?)
• t0.5 mg/cm2
• I10 pnA
• eFMA10

20 X 100Sn /day
Fragmentation 1 X 100Sn /day MSU 20 X 100Sn
/day GSI Very good channel selection but in-beam
spectroscopy impossible
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Experimental approach

• Main emphasis on excited states in 100Sn and
  single-particle states and nucleon-nucleon
  interactions using in-beam spectroscopy
• More intense beams
• Push rates in GAMMASPHERE (x5)
• Digital GS
• Beams 100-200 pnA
• Channel selection tagging with decays (bg, bp,
  p, a)
• High granularity DSSD
• Secondary fusion-evaporation reactions
• In-flight radioactive beams
• Beams 10 pmA

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100Sn region experimental status
114Ba
115Ba
116Ba
2p
CN
112Cs
113Cs
109Xe
110Xe
111Xe
112Xe
2p
CN
N50
108I
109I
b-delayed protons with sizeable
branch Observed/expected
105Te
106Te
107Te
108Te
2p
CN
105Sb
103Sb
104Sb
Predictions
101Sn
102Sn
104Sn
2p
100Sn
99Sn
103Sn
Z50
CN
Excited states Fusion-evaporation
103In
101In
99In
98In
97In
102In
100In
CN
101Cd
100Cd
96Cd
99Cd
98Cd
97Cd
95Cd
Decay properties Fusion-evaporation
CN
100Ag
96Ag
97Ag
98Ag
99Ag
95Ag
94Ag
93Ag
Decay properties Existence Fragmentation
95Pd
93Pd
94Pd
97Pd
96Pd
98Pd
99Pd
92Pd
CN
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Secondary fusion-evaporation reactions

• Transfer, deep inelastic, fusion evaporation
• 56Ni50Cr-gt100Sna2n, 60Zn40Ca-gt100Sn,

Intense stable beam
Secondary RIB
100Sn
Tagging
Mass separator
In-flight separator
58Ni 10 pma
12C 1mg/cm2 s100 mb
e50
25/day
e10
50Cr 1mg/cm2 s1 mb
56Ni 3X107
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Examples

• excited states in 100In (p-1-n), 99In (p-1)
• excited states in 100Sn
• Excited states in 99Sn(n-1),98In(p-1-n-1)
• Excited states in 105Te (gas filled separator)
• 94Ag, 96,97Cd p and 2p emitting isomers

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Thank you!