The axial vector resonances, a1 and h1, in the π−p charge exchange reaction (original) (raw)

Experimental study of the axial-vector resonances of a1 and h1 in the π-p charge exchange reaction

Physics Letters B, 1992

A high-statistics experiment on the reaction n-p--,n +n-n°n at 8.06 GeV/c has been performed using a spectrometer detecting both charged particles and gamma rays. A partial-wave analysis based on the isobar model has been carried out for ~+x-Tr ° data in the mass range between 0.86 and 1.50 GeV for four t' regions: 0.0-0.1, 0.1-0.25, 0.25-0.45 and 0.45-0.95 (GeV/c2). Two axial-vector resonances, a~ (1260) and h~ , were observed in the analysis. The masses and widths of a~ and h t were determined to be M(a~ ) = 1121 + 8 MeV, F(a, ) = 239 + 11 MeV, M( h~ ) = 1168 + 4 MeV and F( hi ) = 345 + 6 MeV, respectively, by fitting the Breit-Wigner formula to the partial wave amplitude. A fit including the Deck type background was also tried in each t' region. The results showed a small effect on these resonance parameters and were consistent with those obtained by the simple Breit-Wigner fitting.

Differential cross sections of the charge-exchange reaction π^{-}p→π^{0}n in the momentum range from 103 to 178 MeV/c

Physical Review C, 2009

Differential cross sections of the charge-exchange reaction π − p → π 0 n in the momentum range from 103 to 178 MeV/c Measured values of the differential cross sections for pion-nucleon charge exchange, π − p → π 0 n, are presented for π − momenta of 103, 112, 120, 130, 139, 152, and 178 MeV/c. Complete angular distributions were obtained by using the Crystal Ball detector at the Alternating Gradient Synchrotron at Brookhaven National Laboratory. Statistical uncertainties of the differential cross sections vary from 3% to 6% in the backward angle region, and from 6% to about 20% in the forward region with the exception of the two most forward angles. The systematic uncertainties are estimated to be about 3% for all momenta. * dmekter@irb.hr † Present address:

Differential cross section of the charge-exchange reaction ��^{���} p��� ��^{0} n in the momentum range from 148 to 323MeV��� c

2004

Measured values of the differential cross section for pion-nucleon charge exchange, π − p → π 0 n, are presented at π − momenta of 148, 174, 188, 212, 238, 271, 298, and 323 MeV/c, a region dominated by the ∆(1232) resonance. Complete angular distributions were obtained using the Crystal Ball detector at the Alternating Gradient Synchrotron (AGS) at Brookhaven National Laboratory (BNL). Statistical uncertainties of the differential cross sections are typically 2-6%, exceptions being the results at the lowest momentum and at the most forward measurements at the five lowest momenta. We estimate the systematic uncertainties to be 3-6%.

Measurements of \pi ^\pm π±,Kπ ± , Kπ±,K^\pm ±,pand± , p and±,pand{\bar{\text {p}}}p¯spectrainproton−protoninteractionsat20,31,40,80and158p ¯ spectra in proton-proton interactions at 20, 31, 40, 80 and 158p¯spectrainproton−protoninteractionsat20,31,40,80and158\text{ GeV }/c$$ GeV / c with the NA61/SHINE spectrometer at the CERN SPS

The European Physical Journal C

Measurements of inclusive spectra and mean multiplicities of π ± , K ± , p andp produced in inelastic p + p interactions at incident projectile momenta of 20, 31, 40, 80 and 158 GeV/c (√ s = 6.3, 7.7, 8.8, 12.3 and 17.3 GeV, respectively) were performed at the CERN Super Proton Synchrotron using the large acceptance NA61/SHINE hadron spectrometer. Spectra are presented as function of rapidity and transverse momentum and are compared to predictions of current models. The measurements serve as the baseline in the NA61/SHINE study of the properties of the onset of deconfinement and search for the critical point of strongly interacting matter.

19 Double π0 Photoproduction on the Proton at GRAAL - Physical Review Letters, June 2003

Double π0 Photoproduction on the Proton at GRAAL - The American Physical Society, Physical Review Letters, June 2003, Vol. 90, N. 22, pp. 222001-1-222001-4, ISSN: 0031-9007, doi: 10.1103/PhysRevLett.90.222001 di Y. Assafiri, O. Bartalini, V. Bellini, J. P. Bocquet, S. Bouchigny , M. Capogni, M. Castoldi, A. D'Angelo, J. P. Didelez, R. Di Salvo, A. Fantini, L. Fichen , G. Gervino, F. Ghio, B. Girolami, A. Giusa, M. Guidal, E. Hourany, V. Kouznetsov, R. Kunne, J. M. Laget, A. Lapik, P. Levi Sandri, A. Lleres, D. Moricciani, V. Nedorezov, D. Rebreyend, C. Randieri, F. Renard, N. Rudnev, C. Schaerf, M. Sperduto, M. C. Sutera, A. Turinge, A. Zucchiatti (2003) Abstract The double π0 photoproduction off the proton has been measured in the beam energy range of 0.65 1.5GeV. The total and differential cross sections and the Σ beam asymmetry were extracted. The total cross section measured for the first time in the third resonance region of the nucleon shows a prominent peak. The interpretation of these results by two independent theoretical models infers mostly the selective excitation of P11- and D13-nucleon resonances.

Study of the hypercharge exchange reactions π+p→K+∑+ and π+p→K+∑+(1385) at 12 GeV/c

Nuclear Physics B, 1985

The results of the study of the 7r+p-~K+2 + (1) and rr+p~K+2+(1385) (2) reactions at 12 GeV/c are presented. The differential cross sections do-~dr in [tmi,[ < It[ < 0.8 (GeV/c) 2 momentum transfer range are measured. The £+ polarisation for ]tl < 0.5 (GeV/c) 2 for reaction (1) is defined. Binary reactions and were selected by analyzing the missing mass spectra for the forward emitted fast K + meson. The total cross sections in the studied momentum transfer range are 20.222.4 p.b and 7.3~: 1.1 ~b for reactions and respectively. The experimental results are compared with the predictions of the Regge models which take into account rescattering and secondary singularities.