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 𝐶⁢𝑃⁢𝑇 invariance in the strangeness sector, is also measured. The obtained value (𝜏Λ−𝜏 ¯ Λ )/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 𝜏 ¯ Λ are in agreement with the corresponding world averages of the Particle Data Group and about a factor of three more precise.

Acharya, S., Adamová, D., Adler, A., Aglieri Rinella, G., Agnello, M., Agrawal, N., et al. (2023). Measurement of the Λ hyperon lifetime. PHYSICAL REVIEW D, 108(3), 1-15 [10.1103/PhysRevD.108.032009].

Measurement of the Λ hyperon lifetime

Agrawal, N.;Alici, A.;Arcelli, S.;Bellini, F.;Carnesecchi, F.;Colocci, M.;Ercolessi, F.;Giacalone, M.;Jacazio, N.;Malfattore, G.;Rubini, N.;Scioli, G.;Strazzi, S.;
2023

Abstract

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 𝐶⁢𝑃⁢𝑇 invariance in the strangeness sector, is also measured. The obtained value (𝜏Λ−𝜏 ¯ Λ )/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 𝜏 ¯ Λ are in agreement with the corresponding world averages of the Particle Data Group and about a factor of three more precise.
2023
Acharya, S., Adamová, D., Adler, A., Aglieri Rinella, G., Agnello, M., Agrawal, N., et al. (2023). Measurement of the Λ hyperon lifetime. PHYSICAL REVIEW D, 108(3), 1-15 [10.1103/PhysRevD.108.032009].
Acharya, S.; Adamová, D.; Adler, A.; Aglieri Rinella, G.; Agnello, M.; Agrawal, N.; Ahammed, Z.; Ahmad, S.; Ahn, S. U.; Ahuja, I.; Akindinov, A.; Al-T...espandi
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11585/954496
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