Search for Narrow Baryons in the $\pi^- p$ Total Cross-section Between 2-{GeV}/$c$ and 14-{GeV}/$c$

The CERN-College de France-Ecole Poly collaboration Barrelet, E. ; Baillon, P. ; Benayoun, Maurice ; et al.
Phys.Lett.B 94 (1980) 541-547, 1980.
Inspire Record 153783 DOI 10.17182/hepdata.27168

A high-statistics search for resonances in the π − p total cross section has been carried out over the incident momentum region from 2 to 14 GeV/ c . The measurements were performed with a transmission technique using multiwire proportional chambers in place of the conventional counter arrays. A microprocessor unit was used for the on-line analysis of the data, allowing a total of ≈ 50 000 events to be examined in a 300 ms burst. The search aimed at detecting the possible formation in π − p collisions of narrow non-strange baryon resonances. The momentum region was uniformly scanned with a total of ≈4500 mmeasurements in fixed fractional momentum steps of d P / P = 5 × 10 −4 . The relative statistical precision of each measurement was d σ / σ = ±0.3%. Within these limits no significant structure was detected.

1 data table

ENERGY SCAN IN MOMENTUM STEPS OF D(PLAB)/PLAB OF 5*10**-4.


Search for Narrow Baryons in $\pi^- p$ Elastic Scattering at Large Angles

The CERN-College de France-Ecole Poly collaboration Baillon, P. ; Barrelet, E. ; Benayoun, Maurice ; et al.
Phys.Lett.B 94 (1980) 533-540, 1980.
Inspire Record 153784 DOI 10.17182/hepdata.27177

Hoping to find resonant structures in the momentum dependence of π − p elastic scattering we have measured the differential cross section for this reaction at c.m. angles near 90°. An intense pion beam (≈ 10 7 π /s) has been used, together with a high incident momentum resolution (d P / P ≈ 2 × 10 −4 ), to scan the region of laboratory momenta from 5.75 to 13.02 GeV/ c (c.m. energy from 3.42 to 5.03 GeV). The sensitivity attained by the experiment is such that signals would have been seen corresponding to the formation of non-strange baryon resonances having width larger than ≈ 0.1 MeV and elasticity larger than a few per cent. Within these limits no resonances were sighted.

1 data table

ENERGY SCAN IN BINS OF D(PLAB)/PLAB OF 5*10**-4 AT FOUR FIXED ANGLES (COS(THETA) = -0.4 TO 0.4).