Ω− produced in K−p reactions at 4.2 GeV/c

doi:10.1016/0550-3213(78)90197-9

Nuclear Physics B

Volume 142, Issue 3, 25 September 1978, Pages 205-219

https://doi.org/10.1016/0550-3213(78)90197-9 Get rights and content

Abstract

Forty $Ω^{−}$ events have been observed in a large (133 events/βb) experiment at 4.2 GeV/c incident K⁻ momentum. Thirty nine of the events come from the three-body reaction $K^{−} p →Ω^{−} K^{+} K^{0}$ . The $Ω^{−}$ is mainly produced in the forward hemisphere (direction of the incident K⁻). The lifetime is measured to be τ = (0.75 _+0.14_−0.11 × 10⁻¹⁰ sec substantially less than the Particle Data Group value of (1.3 _−0.3^+0.2) × 10⁻¹⁰ sec. The mass is determined to be 1671.7 ± 0.6 MeV, in good agreement with other determinations. The decay asymmetry parameter α (for the decay mode $Ω^{−} → Λ K^{−}$ ) is found to be −0.2 ± 0.4.

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^★: Now at Carleton University, Ottawa, Canada.

^★★: CERN visiting scientist from the Tara Institute of fundamental research, Bombay, India.

^★★★: Now at University of Leiden, The Netherlands.

^■: Now at LBL, Berkeley, USA.

^‡: This investigation is supported by the joint research programs of FOM and ZWO.

^■■: Now at University of Leiden, The Netherlands.

^■■■: Now at DESY, Federal Republic of Germany.

^■: Now at State Computer Centre, Heerlen, The Netherlands.

^■■: Now at NIKHEF-H, The Netherlands.

^■■■: Now at CERN.

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Nuclear Physics B

Abstract

References (16)

Nucl. Phys.

Phys. Lett.

Nucl. Phys.

Phys. Lett.

Rev. Mod. Phys.

Phys. Lett.

Phys. Rev.

Cited by (23)

QCD and the strange baryon spectrum

Measurement of decay parameters and polarization in inclusive Ξ<sup>-</sup> production from K<sup>-</sup>p interactions

Experiments with the CERN SPS hyperon beam

Measurement of Ω<sup>-</sup> decay properties in the CERN SPS hyperon beam

≡ Hypernuclei

The interaction of kaons with nucleons and nuclei