SwePub
Sök i LIBRIS databas

  Utökad sökning

(WFRF:(Lantz Mattias)) pers:(Pomp Stephan)
 

Sökning: (WFRF:(Lantz Mattias)) pers:(Pomp Stephan) > Estimating angular ...

  • Gao, ZhihaoUppsala universitet,Tillämpad kärnfysik (författare)

Estimating angular momenta of fission fragments from isomeric yield ratios using TALYS

  • Artikel/kapitelEngelska2024

Förlag, utgivningsår, omfång ...

  • American Physical Society,2024
  • electronicrdacarrier

Nummerbeteckningar

  • LIBRIS-ID:oai:DiVA.org:uu-537081
  • https://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-537081URI
  • https://doi.org/10.1103/PhysRevC.109.064626DOI

Kompletterande språkuppgifter

  • Språk:engelska
  • Sammanfattning på:engelska

Ingår i deldatabas

Klassifikation

  • Ämneskategori:ref swepub-contenttype
  • Ämneskategori:art swepub-publicationtype

Anmärkningar

  • Background: Angular momenta of fission fragments considerably higher than that of the fissioning nucleus have been observed in many experiments, raising the question of how these high angular momenta are generated. Wilson et al. have proposed a model for the angular momentum as a function of the mass of fission products based on the assumption that the angular momentum is generated from the collective motion of nucleons in the ruptured neck of the fissioning system. This assumption has caused a lot of debate in the community.Purpose: To estimate the angular momenta of fission fragments based on the observed isomeric yield ratios in 25 -MeV proton -induced fission of 238 U.Method: A surrogate model of the fission code general description of fission observables (GEF) has been developed to generate properties of primary fission fragments. Based on the excitation energy and angular momentum of fission fragments from GEF, an energy -versus -angular -momentum matrix is reconstructed using a set of parameters. With such matrices as input, the reaction code TALYS is used to calculate the deexcitation of the fission fragments, including the population of the isomers, from which the isomeric yield ratios are obtained. By varying one of the parameters, the root -mean -square angular momentum ( J rms ), which determines the angular momentum distribution of the matrix, J rms -dependent isomeric yield ratios are obtained. Considering all primary fission fragments contributing to the isomeric yield ratio for a given fission product, the average angular momentum of those fragments is estimated.Results: Data of 31 isomeric yield ratios in 25 -MeV proton -induced fission of 238 U were analyzed. From the analysis, the average J rms , equivalent to average angular momentum J av , with uncertainties are obtained for 24 fission products, while in seven cases no conclusive result for the angular momentum could be obtained. Furthermore, considering the neutron emissions of the primary fission fragments, the average angular momentum as a function of the average mass number of the primary fission fragment was estimated.Conclusion: A mass dependency of the average angular momentum is observed in the proton -induced fission of 238 U. Moreover, the average angular momenta for mass numbers larger than 131 could be fairly well described by the parametrization proposed by Wilson et al. However, the average angular momenta of 130 Sn and 131 Te cannot be described by Wilson's model, which suggests a different lower limit for the validation of the parametrization in the model. In general, higher average angular momenta for A 132 are observed in the present work compared to those from Wilson et al. This is likely due to the higher excitation energy of the fissioning nuclei in this work. Furthermore, the first systematic observation of the average angular momenta of fission products in the symmetric mass region is presented. In this region, a decreasing trend with mass number is observed, which cannot be explained by the proposal in Wilson's paper. Thus, a different mechanism is needed to explain this observation.

Ämnesord och genrebeteckningar

Biuppslag (personer, institutioner, konferenser, titlar ...)

  • Solders, Andreas,PhD,1976-Uppsala universitet,Tillämpad kärnfysik(Swepub:uu)andso900 (författare)
  • Al-Adili, AliUppsala universitet,Tillämpad kärnfysik(Swepub:uu)alial125 (författare)
  • Cannarozzo, SimoneUppsala universitet,Tillämpad kärnfysik(Swepub:uu)simca590 (författare)
  • Lantz, Mattias,1971-Uppsala universitet,Tillämpad kärnfysik(Swepub:uu)malan676 (författare)
  • Pomp, Stephan,1968-Uppsala universitet,Tillämpad kärnfysik(Swepub:uu)steppomp (författare)
  • Sjöstrand, Henrik,1978-Uppsala universitet,Tillämpad kärnfysik(Swepub:uu)hesjo677 (författare)
  • Uppsala universitetTillämpad kärnfysik (creator_code:org_t)

Sammanhörande titlar

  • Ingår i:Physical Review C: American Physical Society109:62469-99852469-9993

Internetlänk

Hitta via bibliotek

Till lärosätets databas

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.

 
pil uppåt Stäng

Kopiera och spara länken för att återkomma till aktuell vy