I would like to start by thanking the organizers for the opportunity

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I would like to start by thanking the organizers
for the opportunity to present the results of
these new experiments along with discussion of
their implications.
Second, I would like to thank the U. S. DOE and
NSF and German BMBF, along with the Alexander
von Humboldt Foundation for support for this
work.
And, I would also like to thank the ISOLDE
technical staff for the intense, clean beams of
Sn ions delivered by the RILIS and the neutron
converter.
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Today, I want to report on new data for the decay
of 135Sn to levels in both 135Sb and 134 Sb.
First, I will review the results of our 2000
experiment, then present an overview of the 2002
experiment, and then focus on new nuclear
structure data The overall goals of these
experiments are new measured nuclear
properties that are useful both for determination
of how nuclear structure evolves as N/Z
increases, and for r-process abundance
calculations. As Karl-Ludwig Kratz has already
talked about the astrophysics and nuclides
with Z lt 50, I will focus on nuclear structure
and decay of nuclides with Z 50.
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This OXBASH calculation shows what the
expectation was at the start of the experiment.
The in-beam data were already available and
the calculation was in good agreement with the
data.
The low position of the 5/2 was the BIG
surprise in this level scheme.
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These are single-particle levels for the
odd-mass Sb nuclides with one proton beyond
the Z 50 closed shell calculated by Alex Brown.
It can be seen that the inclusion of neutron
skin effects DOES result in a lower 5/2 and
3/2 low-angular momentum states with
respect to the higher angular momentum 7/2 and
11/2- states.

J. Shergur et al., PRC 65, 034313 (2002)
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In column (d), the single- particle d5/2 basis
level has been lowered by 300 keV. Some
levels, shown in blue are not changed much, but
some shown in red are also lowered in
energy. Hence, there was much interest in
improved data with which to test the overall
effect of this change.
Exp 2000
exp
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Sn-135 July 2000
First 300 ms
Second 300 ms
Laser off
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Sn-135 August 2002 with the converter
Laser on
Laser off
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RILIS plus neutron converter
Sn-135 decay low-energy gamma rays
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2000
2002
318 keV line in Sb-134
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2000
2002
The conclusion is that the calculation with the
basis state lowered provides a better fit for
the newly observed 9/2 and 1/2 levels. 8
levels are predicted between 1 and 1.5 MeV
with 5/2, 7/2, 9/2 spin and parity, exactly
the number observed.
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Peaks left over for Sb-134 levels.
Peaks assigned to levels in Sb-135.
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Korgul et al., note that they did not observe the
line at 171 keV, but took it from some
fission-gamma data.
Korgul et al. ENAM
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If this group connected to the level at 331 keV,
then the lines at 53 and 171 should have
appeared in the 162 gate and and the 162 should
have appeared in the 52-keV gate.
6- 617 5- 441 7- 279
338
176
114
162
If this group connected to the level at 384 keV,
then the line at 171 should have also been
observed in the 162 gate.
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Sn-135 decay
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52
318
Sn-134 decay RILIS neutron converter
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171
318
52
Sn-135 decay RILIS neutron converter
No gamma rays at 114, 162, or 176 keV are
observed in the decay of Sn-134, but perhaps
there is a hint of a peak at 171.
114
162
176
Sn-134 decay RILIS neutron converter
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These lines (except 2417) are seen in
coincidence with gamma rays from known levels
and establish 3 new at high energy.
Sn-134 decay to Sb-134 levels
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New Sn-135 bdn decay
New Sn-134 decay
Korgul et al.
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i13/2 2713 (100) keV
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The agreement between the levels for Sb-135
calculated by the OXBASH code is quite good,
nearly every level expected up to 1500 keV has
now been observed. In particular, the new data
for the 9/2 level and possible 1/2 level are in
accord with the level structure calculated with
the d-5/2 single-particle basis state that has
been lowered by 300 keV.
For Sb-134, there is found to be quite good
agreement with the OXBASH calculations performed
in 1992 for both the ground-state multiplet and
for the excited 1- levels and high-spin levels,
that were based on an A-1/3 scaling from the
Bi-210 levels and on mostly estimated positions
for the single-neutron energies
What emerges is the rather close agreement
between theory and experiment for both Sb-134
and Sb-135, in contrast to the situation shown
by Karl-Ludwig Kratz on Monday for the Cd and In
nuclides where the agreement worsens as N
increases.