Test of the statistical model in<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mmultiscripts><mml:mi mathvariant="normal">Mo</mml:mi><mml:mprescripts /><mml:none /><mml:mrow><mml:mn>96</mml:mn></mml:mrow></mml:mmultiscripts></mml:math>with the<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mi>BaF</mml:mi><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub><mml:mi>γ</mml:mi></mml:mrow></mml:math>calorimeter DANCE array

Sheets, S. A.; Agvaanluvsan, U.; Becker, J. A.; Bečvář, F.; Haight, R. C.; Jändel, M.; Krtička, M.; Mitchell, G. E.; O’Donnell, J. M.; Parker, W.; Reifarth, R.; Rundberg, R. S.; Sharapov, É. I.; Ullmann, J. L.; Vieira, D. J.; Wilhelmy, J. B.; Wouters, J.M.; Wu, C. Y.

doi:10.1103/physrevc.79.024301

Phys. Rev. C

2009

DOI: 10.1103/physrevc.79.024301

|View full text |Cite

Test of the statistical model inMo96with theBaF2γcalorimeter DANCE array

S. A. Sheets

U. Agvaanluvsan

J. A. Becker

et al.

Help me understand this report

Search citation statements

Order By: Relevance

Paper Sections

Select...

Citation Types

Supporting

Mentioning

Contrasting

Year Published

2009

2020

Publication Types

Select...

Article6

Relationship

Self Cite1

Independent5

Authors

Journals

Cited by 18 publications

(21 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…On the basis of a very few measured total radiation widths γ , it was suggested [7] that significant nonstatistical effects affected this decay. In contrast, it was found that the extreme statistical model was in very good agreement with two-step cascade γ spectra following thermal neutron capture [4] as well as coincidence-pulse-height spectra and other data for neutron-resonance capture [5].Resolving these controversies is of central importance for applications such as advanced nuclear fuel cycles [8] and astrophysical nucleosynthesis studies. For example, the PSF shape can have substantial impact on astrophysical reaction rates [9] in explosive environments, and therefore significantly impact the resulting nucleosynthesis.…”

mentioning

confidence: 99%

mentioning

confidence: 99%

“…Widely different shapes for the photon strength function (PSF), representing the decay strength as a function of γ -ray energy, have resulted from various measurements [1][2][3]. In addition, the enhancement in strength at low γ -ray energies reported for molybdenum isotopes [1,2] has been called into question [4,5], although more recent data [6] strongly support its existence. There is also disagreement about the nature of γ decay following neutron capture on molybdenum isotopes.…”

mentioning

confidence: 99%

“…[4,5,17]). A complete level scheme (i.e., level energies E f , spins J f , and parities π f ), above a critical excitation energy E c , was generated according to the adopted LD.…”

mentioning

confidence: 99%

“…The question arises whether such a doorway mechanism is contradicted by the reasonably good agreement between statistical-model-simulated and measured γ -ray spectra for two-step cascades following thermal neutron capture [4], and multiple-step cascades for resonance capture [5] on 95 Mo. As thermal capture does not proceed through a resonance, it may not be affected by the doorway.…”

mentioning

confidence: 99%

See 4 more Smart Citations

Extreme nonstatistical effects inγdecay of95Mo neutron resonances

et al. 2013

View full text Add to dashboard Cite

We demonstrate that high-quality total radiation width ( γ ) data are a virtually untapped resource for testing and improving nuclear models. To this end, we obtained unprecedentedly large sets of γ values for all six sand p-wave J π values for 95 Mo neutron resonances. We show that γ distributions simulated in the framework of the nuclear statistical model are in sharp disagreement with the data. Simulations modified to include doorway effects resulted in much better agreement. These results call into question the reliability of the nuclear statistical model. There has been significant controversy surrounding γ decay of molybdenum isotopes below the neutron separation energy. Widely different shapes for the photon strength function (PSF), representing the decay strength as a function of γ -ray energy, have resulted from various measurements [1][2][3]. In addition, the enhancement in strength at low γ -ray energies reported for molybdenum isotopes [1,2] has been called into question [4,5], although more recent data [6] strongly support its existence. There is also disagreement about the nature of γ decay following neutron capture on molybdenum isotopes. On the basis of a very few measured total radiation widths γ , it was suggested [7] that significant nonstatistical effects affected this decay. In contrast, it was found that the extreme statistical model was in very good agreement with two-step cascade γ spectra following thermal neutron capture [4] as well as coincidence-pulse-height spectra and other data for neutron-resonance capture [5].Resolving these controversies is of central importance for applications such as advanced nuclear fuel cycles [8] and astrophysical nucleosynthesis studies. For example, the PSF shape can have substantial impact on astrophysical reaction rates [9] in explosive environments, and therefore significantly impact the resulting nucleosynthesis. In addition, as the nuclear statistical model is used to calculate almost all rates for nuclides beyond the reach of current experiments, it is important to test basic assumptions of this model.Total radiation widths of neutron resonances represent a virtually untapped source of data in this endeavor. Due to the very large number of levels below the neutron binding energy B n , there are thousands of channels by which γ decay can occur following resonance neutron capture, a few of which are schematically illustrated in Fig. 1. Hence, energies E γ of these transitions span the entire range of level density (LD) and PSF below B n . The total radiation width γ is the sum of all the partial widths for the initial (primary) γ transitions from the resonance.According to the statistical model, strengths of each of these primary transitions follow the Porter-Thomas distribution (PTD) [10], with average strength proportional to the PSF * Corresponding author.(with an appropriate energy factor, which is E 3 γ for dipole transitions) at the corresponding energy. It is further assumed that all, or at least the vast majority, of the channels are indepen...

show abstract

mentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

“…[4,5,17]). A complete level scheme (i.e., level energies E f , spins J f , and parities π f ), above a critical excitation energy E c , was generated according to the adopted LD.…”

mentioning

confidence: 99%

mentioning

confidence: 99%

See 3 more Smart Citations

Extreme nonstatistical effects inγdecay of95Mo neutron resonances

et al. 2013

View full text Add to dashboard Cite

show abstract

Current and Future Research at DANCE

Jändel

Baramsai

Couture

et al. 2015

EPJ Web of Conferences

Self Cite

View full text Add to dashboard Cite

Abstract. An overview of the current experimental program on measurements of neutron capture and neutron induced fission at the Detector for Advanced Neutron Capture Experiments (DANCE) is presented. Three major projects are currently under way: 1) high precision measurements of neutron capture cross sections on Uranium isotopes, 2) research aimed at studies of the short-lived actinide isomer production in neutron capture on 235 U and 3) measurements of correlated data of fission observables. New projects include developments of auxiliary detectors to improve the capability of DANCE. We are building a compact, segmented NEUtron detector Array at DANCE (NEUANCE), which will be installed in the central cavity of the DANCE array. It will provide experimental information on prompt fission neutrons in coincidence with the prompt fission gamma-rays measured by 160 BaF 2 crystals of DANCE. Unique correlated data will be obtained for neutron capture and neutron-induced fission using the DANCE-NEUANCE experimental set up in the future.

show abstract

Quenching of transition results from 2p-1h doorway mechanism by p-wave neutron excitation *

et al. 2020

View full text Add to dashboard Cite

The ratio of transition-intensities from the initial capture state to low-lying states may represent the model-independent -strength function, which reflects the effects of different neutron-capture reaction mechanisms. The extraordinary quenching of the transition from the p-wave neutron radiative capture in Fe is observed, for the first time, from the pronounced enhancement of the -strength function ratios and . The 2p-1h doorway excitation leads to suppression of the transition to the ground state and the enhancement of the and transitions to the first and second excited states, respectively. The sub-shells supply the exact number of spaces required for the 2p-1h configuration, which features the neutron capture mechanism in the vicinity of A= 55.

show abstract

scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.

Contact Info

hi@scite.ai

10624 S. Eastern Ave., Ste. A-614

Henderson, NV 89052, USA

Blog Terms and Conditions API Terms Privacy Policy Contact Cookie Preferences Do Not Sell or Share My Personal Information

Made with 💙 for researchers

Part of the Research Solutions Family.

Test of the statistical model inMo96with theBaF2γcalorimeter DANCE array

Cited by 18 publications

References 22 publications

Extreme nonstatistical effects inγdecay of95Mo neutron resonances

Extreme nonstatistical effects inγdecay of95Mo neutron resonances

Current and Future Research at DANCE

Quenching of transition results from 2p-1h doorway mechanism by p-wave neutron excitation *

Contact Info

Product

Resources

About