WA89 experiment

Physics experiment

The WA89 experiment (Omega/Hyperon) was a particle physics experiment operating from 1989 to 1994 in the West Area of the SPS accelerator at CERN.^[1]^[2] It was a large acceptance forward spectrometer dedicated to the spectroscopy of charmed strange baryons and exotic multiquark states produced by a hyperon beam.

The initial aims of the hyperon beam experiment were to investigate charmed-strange quark baryons, verify and investigate the U(3100) and study baryonic resonances and decays whilst searching for the double-strange dibaryon H.^[3]

Experimental setup

The WA89 experiment consisted of a beamline and a forward spectrometer. The beamline contained the proton beam hitting the hyperon production target which was followed by a 13 m long hyperon channel. Three dipoles were used to provide a bending power of 8.4 Tm. The target region consisted of two adjacent targets surrounded by muon strip detectors. Following this, a 15 m long Λ decay region was filled with six drift chamber sets and a spectrometer magnet.^[4]

The beam particle trajectories along with their momenta were measured with a scintillating fibre hodoscope in the beamline and a silicon microstrip detector at the end of the line.^[1]

References

^ ^a ^b Alexandrov, Yu. A; Clement, M; Dropmann, F; Fournier, A; Grafström, P; Hubbard, E; Paul, S; Siebert, H. W; Trombini, A; Zavertiaev, M (1998-05-11). "The high-intensity hyperon beam at CERN". Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. 408 (2): 359–372. arXiv:physics/9801006. doi:10.1016/S0168-9002(98)00228-9. ISSN 0168-9002.
^ "Experiments at CERN: WA89/Omega/Hyperon—Hyperon beam experiment". Retrieved 2020-05-15.
^ Forino, A; Gessaroli, R; Quareni-Vignudelli, A; Viaggi, F; Barberis, D (1987). "Proposal for a new hyperon beam experiment at the CERN-SPS using the Omega facility". CERN. Geneva. SPS Experiments Committee.
^ Paul, S. (1989). "1. The new hyperon beam experiment at CERN". AIP Conference Proceedings. 196. AIP: 280–284. doi:10.1063/1.38934.