Measurement of the Λ hyperon lifetime

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Acharya S., Adamová D., Adler A., Aglieri Rinella G., Agnello M., Agrawal N., ...More

Physical Review D, vol.108, no.3, 2023 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 108 Issue: 3
  • Publication Date: 2023
  • Doi Number: 10.1103/physrevd.108.032009
  • Journal Name: Physical Review D
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Aerospace Database, Chemical Abstracts Core, INSPEC, zbMATH
  • Yıldız Technical University Affiliated: Yes


A new, more precise measurement of the Λ hyperon lifetime is performed using a large data sample of Pb-Pb collisions at sNN=5.02 TeV with ALICE. The Λ and Λ¯ hyperons are reconstructed at midrapidity using their two-body weak decay channel Λ→p+π- and Λ¯→p¯+π+. The measured value of the Λ lifetime is τΛ=[261.07±0.37(stat.)±0.72(syst.)] ps. The relative difference between the lifetime of Λ and Λ¯, which represents an important test of CPT invariance in the strangeness sector, is also measured. The obtained value (τΛ-τΛ¯)/τΛ=0.0013±0.0028(stat.)±0.0021(syst.) is consistent with zero within the uncertainties. Both measurements of the Λ hyperon lifetime and of the relative difference between τΛ and τΛ¯ are in agreement with the corresponding world averages of the Particle Data Group and about a factor of three more precise.