Author: C.D. Nesaraja |  Citation: ENSDF |  Cutoff date: 31-Mar-2015 

Author: C.D. Nesaraja |  Citation: Nucl. Data Sheets 115, 1 (2014) |  Cutoff date: 31-Jul-2013 

 Full ENSDF file | Adopted Levels (PDF version) 

Q(β-)=-13680 keV SYS(n)= 15740 keV SYS(p)= -641 keV 42Q(α)= -1600 keV 90
Reference: 2012WA38,2014DE41

  A  69Kr ε decay (28 MS) 

General Comments:

2011Ro18: 69Br produced at the Coupled Cyclotron Facility of the National Superconducting Cyclotron Laboratory (NSCL) by a secondary beam consisting of 69As (23.9%), 70Se (66.7%) and 71Br (9.4%) (produced in fragmentation of 78Kr beam at E=140 MeV/nucleon with a 9Be target) impinging on a polypropylene reaction target. Emitted protons were detected by the High Resolution Array (HIRA) with sixteen ΔE-E telescopes, each configured with a double-sided silicon strip detector and backed by four CsI(Tl) crystals. Heavy projectile-like residues were detected in the focal plane of the S800 spectrograph, then identified by energy loss and time of flight. Measured protons in coincidence with 68,69Se and 67,68As, ΔE, ToF, Q(β-)value. Deduced proton separation energy, mass excess. Monte Carlo simulation. Implications for the astrophysical rp-process.

1996Pf01: Searched for 69Br in the fragmentation of 78Kr projectile with 75 MeV/u on a 58Ni target. Estimated T1/2 from the absence of 69Br.

1995Bl06: Found no evidence for 69Br in the fragmentation of 78Kr beam at 73 MeV/u on a Ni target. Deduced that 69Br is proton unbound by at least 450 keV to yield a T1/2 less than about 100 ns.

1995He39: Attempt to measure the β+ decay half-life of 69Br in the fragmentation of 78Kr at 70 MeV/u on a natural Ni target was not successful because of low count rate.

1995MoZV: searched for 69Br in the fragmentation of a 75 MeV/u 78Kr beam incident on a 58Ni target. No events that could be attributed to 69Br were observed.

1991Mo10: identified 69Br activity in the fragmentation of 78Kr beam at 65 MeV/u on an enriched 58Ni target. However, the authors state that it is difficult to conclude from such a small number of events whether 69Br has been in fact identified or whether the events are due to background processes.

1990Ro15: searched for the g.s. p decays of 69Br using the 40Ca(32S,p2n) reaction with E(32S)=200 MeV. No p groups that could be assigned to 69Br were observed. If the production cross section of 69Br is of the order of 150 microbarns, then 69Br must have p half-life shorter than 300 μs or longer than 30 ms.

1989Ho19: searched for p radioactivity of 69Br using the 40Ca(32S,p2n) reaction. Found no p radioactivity in the energy range 250-600 keV and a T1/2 range of 10 μs -100 ms and a production cross section lower limit of 1 microbarn.

Others: 1999Ja02, 1997Or04, 1989HoZG, 1989HoZQ, 1978BaYE, 1977JaZT

Q-value: ΔQ(β-)=400, ΔS(n)=310 (syst,2012Wa38)

Q-value: All values except S(p) are from 2012Wa38.

XREFJπ(level) T1/2(level)
     0.0A (5/2-) < 24 ns
% p = 100
   0+XA (3/2-) % p = 100
  3153 55 A (5/2-) % p = 100

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Additional Level Data and Comments:


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