Enhanced γ -Ray Emission from Neutron Unbound States Populated in β Decay

Tain, J. L.; Valencia, E.; Algora, A.; Agramunt, J.; Rubio, B.; Rice, S.; Gelletly, W.; Regan, P.; Zakari-Issoufou, A. -A.; Fallot, M.; Porta, A.; Rissanen, J.; Eronen, T.; Äystö, J.; Batist, L.; Bowry, M.; Bui, V. M.; Caballero-Folch, R.; Cano-Ott, D.; Elomaa, V. -V.; Estevez, E.; Farrelly, G. F.; Garcia, A. R.; Gomez-Hornillos, B.; Gorlychev, V.; Hakala, J.; Jordan, M. D.; Jokinen, A.; Kolhinen, V. S.; Kondev, F. G.; Martínez, T.; Mendoza, E.; Moore, I.; Penttilä, H.; Podolyák, Zs.; Reponen, M.; Sonnenschein, V.; Sonzogni, A. A.

doi:10.1103/PhysRevLett.115.062502

Title: Enhanced $γ$ -Ray Emission from Neutron Unbound States Populated in $β$ Decay

Journal Article · Sat Aug 01 00:00:00 EDT 2015 · Physical Review Letters

DOI:https://doi.org/10.1103/PhysRevLett.115.062502· OSTI ID:1240585

Tain, J. L. ^[1]; Valencia, E. ^[1]; Algora, A. ^[1]; Agramunt, J. ^[1]; Rubio, B. ^[1]; Rice, S. ^[2]; Gelletly, W. ^[2]; Regan, P. ^[2]; Zakari-Issoufou, A. -A. ^[3]; Fallot, M. ^[3]; Porta, A. ^[3]; Rissanen, J. ^[4]; Eronen, T. ^[4]; Äystö, J. ^[5]; Batist, L. ^[6]; Bowry, M. ^[2]; Bui, V. M. ^[3]; Caballero-Folch, R. ^[7]; Cano-Ott, D. ^[8]; Elomaa, V. -V. ^[4] more »

Univ. of Valencia (Spain). Institute of Corpuscular Physics
Univ. of Surrey, Guildford (United Kingdom). Dept. of Physics
Univ. de Nantes, Nantes (France)
Univ. of Jyvaskyla (Finland). Dept. of Physics
Univ. of Helsinki (Finland). Helsinki Institute of Physics
Petersburg Nuclear Physics Institute, Gatchina (Russia)
Universitat Politecnica de Catalunya, Barcelona (Spain)
Centre for Energy, Environment and Technology (CIEMAT), Madrid (Spain)
Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division
Brookhaven National Lab. (BNL), Upton, NY (United States)

Total absorption spectroscopy was used to investigate the β -decay intensity to states above the neutron separation energy followed by γ -ray emission in ^87,88Br and ⁹⁴Rb. Accurate results were obtained thanks to the careful control of systematic errors. An unexpectedly large γ intensity was observed in all three cases extending well beyond the excitation energy region where neutron penetration is hindered by low neutron energy. The γ branching as a function of excitation energy was compared to Hauser-Feshbach model calculations. For ⁸⁷Br and ⁸⁸Br the branching reaches 57% and 20% respectively, and could be explained as a nuclear structure effect. Some of the states populated in the daughter can only decay through the emission of a large orbital angular momentum neutron with a strongly reduced barrier penetrability. In the case of neutron-rich ⁹⁴Rb the observed 4.5% branching is much larger than the calculations performed with standard nuclear statistical model parameters, even after proper correction for fluctuation effects on individual transition widths. The difference can be reconciled introducing an enhancement of one order-of-magnitude in the photon strength to neutron strength ratio. An increase in the photon strength function of such magnitude for very neutron-rich nuclei, if it proved to be correct, leads to a similar increase in the (n, γ) cross section that would have an impact on r process abundance calculations.

View Accepted Manuscript (DOE)

View Accepted Manuscript (Publisher)

Cite

Export

Save

Research Organization:: Brookhaven National Lab. (BNL), Upton, NY (United States)

Sponsoring Organization:: USDOE Office of Science (SC)

Grant/Contract Number:: SC00112704; AC02-06CH11357; FPA2008-06419; FPA2010-17142; FPA2011-24553

OSTI ID:: 1240585

Alternate ID(s):: OSTI ID: 1209177

Report Number(s):: BNL-108020-2015-JA; PRLTAO; R&D Project: EST-003-NEFA; KB0301041

Journal Information:: Physical Review Letters, Vol. 115, Issue 6; ISSN 0031-9007

Publisher:: American Physical Society (APS)Copyright Statement

Country of Publication:: United States

Language:: English

Citation Metrics:

Cited by: 33 works

Citation information provided by
Web of Science

References (36)

Gamma-ray emission in competition with neutron emission in the beta decay of 87Br Slaughter, D. R.; Nuh, F. M.; Shihab-Eldin, A. A. Physics Letters B, Vol. 38, Issue 1 https://doi.org/10.1016/0370-2693(72)90190-6	journal	January 1972
Gamma-ray competition with neutron emission in the decay of 137I Nuh, F. M.; Slaughter, D. R.; Prussin, S. G. Physics Letters B, Vol. 53, Issue 5 https://doi.org/10.1016/0370-2693(75)90211-7	journal	January 1975
Gamma-ray decay schemes for ${}^{93}{Kr}$ , ${}^{93}{Rb}$ , and ${}^{93}{Sr}$ Bischof, C. J.; Talbert, W. L. Physical Review C, Vol. 15, Issue 3 https://doi.org/10.1103/PhysRevC.15.1047	journal	March 1977
Investigation of beta strength functions by neutron and gamma-ray spectroscopy Kratz, K. -L.; Rudolph, W.; Ohm, H. Nuclear Physics A, Vol. 317, Issue 2-3 https://doi.org/10.1016/0375-9474(79)90486-X	journal	April 1979
Decay of mass-separated ${}^{141}{Cs}$ to ${}^{141}{Ba}$ and systematics of $N = 85$ isotones Yamamoto, H.; Wohn, F. K.; Sistemich, K. Physical Review C, Vol. 26, Issue 3 https://doi.org/10.1103/PhysRevC.26.1215	journal	September 1982
The beta-decay of95Rb and97Rb Kratz, K. -L.; Ohm, H.; Schr�der, A. Zeitschrift f�r Physik A Atoms and Nuclei, Vol. 312, Issue 1-2 https://doi.org/10.1007/BF01411659	journal	March 1983
$β$ decay of the $π f_{5 / 2}$ ground state of ${}^{77}{Cu}$ studied with $225$ MeV and $0.2$ MeV purified radioactive beams Ilyushkin, S. V.; Winger, J. A.; Gross, C. J. Physical Review C, Vol. 80, Issue 5 https://doi.org/10.1103/PhysRevC.80.054304	journal	November 2009
$β$ -decay studies of the transitional nucleus ${}^{75}{Cu}$ and the structure of ${}^{75}{Zn}$ Ilyushkin, S. V.; Winger, J. A.; Rykaczewski, K. P. Physical Review C, Vol. 83, Issue 1 https://doi.org/10.1103/PhysRevC.83.014322	journal	January 2011
The essential decay of pandemonium: A demonstration of errors in complex beta-decay schemes Hardy, J. C.; Carraz, L. C.; Jonson, B. Physics Letters B, Vol. 71, Issue 2 https://doi.org/10.1016/0370-2693(77)90223-4	journal	November 1977
Radiative neutron captures by neutron-rich nuclei and the r-process nucleosynthesis Goriely, S. Physics Letters B, Vol. 436, Issue 1-2 https://doi.org/10.1016/S0370-2693(98)00907-1	journal	September 1998
Changes in r -process abundances at late times Surman, R.; Engel, J. Physical Review C, Vol. 64, Issue 3 https://doi.org/10.1103/PhysRevC.64.035801	journal	August 2001
Dynamical $r$ -process studies within the neutrino-driven wind scenario and its sensitivity to the nuclear physics input Arcones, A.; Martínez-Pinedo, G. Physical Review C, Vol. 83, Issue 4 https://doi.org/10.1103/PhysRevC.83.045809	journal	April 2011
Astrophysical Reaction Rates From Statistical Model Calculations Rauscher, Thomas; Thielemann, Friedrich-Karl Atomic Data and Nuclear Data Tables, Vol. 75, Issue 1-2 https://doi.org/10.1006/adnd.2000.0834	journal	May 2000
The GT resonance revealed in β+-decay using new experimental techniques Algora, A.; Cano-Ott, D.; Rubio, B. Nuclear Physics A, Vol. 654, Issue 1 https://doi.org/10.1016/S0375-9474(00)88536-X	journal	July 1999
$β$ decay of $^{97} Ag$ : Evidence for the Gamow-Teller resonance near $^{100} Sn$ Hu, Z.; Batist, L.; Agramunt, J. Physical Review C, Vol. 60, Issue 2 https://doi.org/10.1103/PhysRevC.60.024315	journal	July 1999
High-energy γ-rays in 87Kr following the decay of 87Br Tovedal, H.; Fogelberg, B. Nuclear Physics A, Vol. 252, Issue 2 https://doi.org/10.1016/0375-9474(75)90498-4	journal	November 1975
Delayed neutrons and high-energy γ-rays from decay of 87Br Nuh, F. M.; Slaughter, D. R.; Prussin, S. G. Nuclear Physics A, Vol. 293, Issue 3 https://doi.org/10.1016/0375-9474(77)90107-5	journal	December 1977
Overlapping $β$ decay and resonance neutron spectroscopy of levels in ${}^{87}{Kr}$ Raman, S.; Fogelberg, B.; Harvey, J. A. Physical Review C, Vol. 28, Issue 2 https://doi.org/10.1103/PhysRevC.28.602	journal	August 1983
Nuclear Data Sheets for A = 87 Helmer, R. G. Nuclear Data Sheets, Vol. 95, Issue 3 https://doi.org/10.1006/ndsh.2002.0006	journal	March 2002
Nuclear Data Sheets for A = 88 McCutchan, E. A.; Sonzogni, A. A. Nuclear Data Sheets, Vol. 115 https://doi.org/10.1016/j.nds.2013.12.002	journal	January 2014
Nuclear Data Sheets for A = 94 Abriola, D.; Sonzogni, A. A. Nuclear Data Sheets, Vol. 107, Issue 9 https://doi.org/10.1016/j.nds.2006.08.001	journal	September 2006
Development and applications of the IGISOL technique Äystö, Juha Nuclear Physics A, Vol. 693, Issue 1-2 https://doi.org/10.1016/S0375-9474(01)00923-X	journal	October 2001
JYFLTRAP: a cylindrical Penning trap for isobaric beam purification at IGISOL Kolhinen, V. S.; Kopecky, S.; Eronen, T. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 528, Issue 3 https://doi.org/10.1016/j.nima.2004.05.029	journal	August 2004
JYFLTRAP: a Penning trap for precision mass spectroscopy and isobaric purification Eronen, T.; Kolhinen, V. S.; Elomaa, V. -V. The European Physical Journal A, Vol. 48, Issue 4 https://doi.org/10.1140/epja/i2012-12046-1	journal	April 2012
Geant4—a simulation toolkit Agostinelli, S.; Allison, J.; Amako, K. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 506, Issue 3 https://doi.org/10.1016/S0168-9002(03)01368-8	journal	July 2003
ENDF/B-VII.1 Nuclear Data for Science and Technology: Cross Sections, Covariances, Fission Product Yields and Decay Data Chadwick, M. B.; Herman, M.; Obložinský, P. Nuclear Data Sheets, Vol. 112, Issue 12 https://doi.org/10.1016/j.nds.2011.11.002	journal	December 2011
The sensitivity of LaBr3:Ce scintillation detectors to low energy neutrons: Measurement and Monte Carlo simulation Tain, J. L.; Agramunt, J.; Algora, A. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 774 https://doi.org/10.1016/j.nima.2014.11.060	journal	February 2015
Pulse pileup correction of large NaI(Tl) total absorption spectra using the true pulse shape Cano-Ott, D.; Tain, J. L.; Gadea, A. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 430, Issue 2-3 https://doi.org/10.1016/S0168-9002(99)00216-8	journal	July 1999
New Beta-delayed Neutron Measurements in the Light-mass Fission Group Agramunt, J.; García, A. R.; Algora, A. Nuclear Data Sheets, Vol. 120 https://doi.org/10.1016/j.nds.2014.07.010	journal	June 2014
The influence of the unknown de-excitation pattern in the analysis of -decay total absorption spectra Tain, J. L.; Cano-Ott, D. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 571, Issue 3 https://doi.org/10.1016/j.nima.2006.09.084	journal	February 2007
Algorithms for the analysis of -decay total absorption spectra Tain, J. L.; Cano-Ott, D. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 571, Issue 3 https://doi.org/10.1016/j.nima.2006.10.098	journal	February 2007
Improved microscopic nuclear level densities within the Hartree-Fock-Bogoliubov plus combinatorial method Goriely, S.; Hilaire, S.; Koning, A. J. Physical Review C, Vol. 78, Issue 6 https://doi.org/10.1103/PhysRevC.78.064307	journal	December 2008
RIPL – Reference Input Parameter Library for Calculation of Nuclear Reactions and Nuclear Data Evaluations Capote, R.; Herman, M.; Obložinský, P. Nuclear Data Sheets, Vol. 110, Issue 12 https://doi.org/10.1016/j.nds.2009.10.004	journal	December 2009
Reactor Decay Heat in ${}^{239}{Pu}$ : Solving the $γ$ Discrepancy in the 4–3000-s Cooling Period Algora, A.; Jordan, D.; Taín, J. L. Physical Review Letters, Vol. 105, Issue 20 https://doi.org/10.1103/PhysRevLett.105.202501	journal	November 2010
New Antineutrino Energy Spectra Predictions from the Summation of Beta Decay Branches of the Fission Products Fallot, M.; Cormon, S.; Estienne, M. Physical Review Letters, Vol. 109, Issue 20 https://doi.org/10.1103/PhysRevLett.109.202504	journal	November 2012
Local and global nucleon optical models from 1 keV to 200 MeV Koning, A. J.; Delaroche, J. P. Nuclear Physics A, Vol. 713, Issue 3-4 https://doi.org/10.1016/S0375-9474(02)01321-0	journal	January 2003

Cited By (1)

Total Absorption Spectroscopy Algora, A.; Rubio, B.; Tain, J. L. Nuclear Physics News, Vol. 28, Issue 2 https://doi.org/10.1080/10619127.2018.1427933	journal	April 2018