Date

Formation of Delta (980) and A2 (1320) in Photon-photon Collisions

The Crystal Ball collaboration Antreasyan, D. ; Aschman, D. ; Besset, D. ; et al.
Phys.Rev.D 33 (1986) 1847, 1986.
Inspire Record 217547 DOI 10.17182/hepdata.23518

The reaction γγ→π0η has been investigated with the Crystal Ball detector at the DESY storage ring DORIS II. Formation of δ(980) and A2(1320) has been observed with γγ partial widths Γγγ(A2)=1.14±0.20±0.2 6 keV and Γγγ(δ)B(δ→πη)=0.19±0.07 −0.07+0.10 keV.

2 data tables

No description provided.

No description provided.


Pion Scattering From C and Ca at 800-{MeV}/$c$

Marlow, Daniel R. ; Barnes, P.D. ; Colella, N.J. ; et al.
Phys.Rev.C 30 (1984) 1662, 1984.
Inspire Record 15083 DOI 10.17182/hepdata.26285

Results from π± elastic and inelastic scattering from C12 and Ca40 are reported. The data were all taken at an incident momentum of 800 MeV/c over an angular range from 4° to 38°. The elastic data are compared to first-order optical model calculations in momentum space; qualitative agreement is obtained. The inelastic data (from C12 only) are compared to distorted-wave Born approximation calculations, and reasonable agreement is found if realistic inelastic transition densities are used.

8 data tables

No description provided.

THE C12* NUCLEUS IS IN THE STATE 2+ (4.4 MEV).

THE C12* NUCLEUS IS IN THE STATE 3- (9.6 MEV).

More…

KAON SCATTERING FROM C AND CA AT 800-MEV/C

Marlow, Daniel R. ; Barnes, P.D. ; Colella, N.J. ; et al.
Phys.Rev.C 25 (1982) 2619-2637, 1982.
Inspire Record 180999 DOI 10.17182/hepdata.26337

Results from K± elastic and inelastic scattering from C12 and Ca40 are reported. The data were all taken at an incident momentum of 800 MeV/c over an angular range from 2° to 38°. The elastic data are compared to first-order optical model calculations in coordinate and momentum space; good qualitative agreement is obtained. The inelastic data (from C12 only) are compared to distorted-wave Born approximation calculations, and good agreement is found if "realistic" inelastic transition densities are used. Although a first-order optical potential description does not describe the data fully, there are strong indications of the increased penetrability of K+ over K− in this energy range. NUCLEAR REACTIONS C12(K±,K±)C12, Ca40(K±,K±)Ca40, E=442 MeV (800 MeV/c), measured σ(θ) for elastic and inelastic scattering, compared to optical model and DWBA calculations, deduced optical potential parameters; θ=2°−38°, Δθ=1°.

4 data tables

X ERROR D(THETA) = 1.0100 DEG.

X ERROR D(THETA) = 1.0100 DEG.

X ERROR D(THETA) = 1.1000 DEG.

More…

Phi-Meson Production in the Reactions pi+- n --> K- K+ n at 6-GeV/c

Cohen, Daniel H. ; Ayres, D.S. ; Diebold, R. ; et al.
Phys.Rev.Lett. 38 (1977) 269, 1977.
Inspire Record 110508 DOI 10.17182/hepdata.21019

A sample of 1200 ϕ mesons produced in the Zweig-rule-forbidden reactions π±N→ϕN shows a flat t distribution (slope=1.7 ± 0.2 GeV−2) and a cross section suppressed by 0.0032±0.0004 relative to π−p→ωn. Natural-parity-exchange ω and ϕ production have similar t dependences, while ω and ϕ production by unnatural-parity exchange differ markedly. Interference between the ϕ and the underlying K¯K S wave indicates substantial nucleon-spin incoherence between the amplitudes for ϕ and S-wave production.

3 data tables

Axis error includes +- 10/10 contribution (RES-DEF(RES=PHI,BACK=CORRECTED)).

Axis error includes +- 10/10 contribution (RES-DEF(RES=PHI,BACK=CORRECTED)).

STATISTICAL ERRORS ONLY.


The Polarized Beam Asymmetry in Photoproduction of eta Mesons from Protons at 2.5-GeV and 3.0-GeV

Bussey, P.J. ; Raine, C. ; Rutherglen, J.G. ; et al.
Phys.Lett.B 61 (1976) 479-482, 1976.
Inspire Record 108515 DOI 10.17182/hepdata.27687

Measurements of the polarised beam asymmetry parameter Σ for eta photoproduction from protons, have been carried out at incident energies of 2.5 GeV and 3.0 GeV, and for various t -values between −0.2 (GeV/c) 2 and −1.2 (GeV/c) 2 . The values of Σ are close to +1 for values of | t | less than 0.7 (GeV/c) 2 , showing that there can be little contribution from unnatural parity exchange in any Regge exchange model of the process, in disagreement with present theories. Differential cross sections for the process werre also measured, and are consistent with those from other experiments.

2 data tables

No description provided.

No description provided.


Production of $\gamma, \Lambda^0, K^0_s$ and $\bar \Lambda^0$ in pp Collisions at 102 GeV/c.

Chapman, J.W. ; Cooper, John W. ; Green, N. ; et al.
Phys.Lett.B 47 (1973) 465-468, 1973.
Inspire Record 81963 DOI 10.17182/hepdata.28029

We have measured cross section for γ , K S °, Λ and Λ production at 102 GeV/ c and find: σ ( γ ) = 170 ± 16 mb ., σ ( K S °) = 4.6 ± 0.5 mb ., σ ( Λ ) = 3.2 ± 0.4 mb ., and σ( Λ ) = 0.23 ± 0.10 mb. Both 〈 n π °〉 and 〈 n Ks °〉 appear to rise linearly with n - while the ratio 〈 n Ks °〉/〈 n π °〉 is approximately independent of n - . The integrated invariant cross section as a function of x as well as d σ /d y and d σ /d p T 2 are presented and compared with other data.

1 data table

No description provided.


Cross Sections and Charged Particle Multiplicities at 102 GeV/c and 405 GeV/c.

Bromberg, C. ; Chaney, D. ; Cohen, Daniel H. ; et al.
Phys.Rev.Lett. 31 (1973) 1563-1566, 1973.
Inspire Record 81962 DOI 10.17182/hepdata.21360

We have measured the total inelastic cross section (σinel) and charged-particle multiplicities obtained in pp collisions at 405 GeV/c. The data are from a preliminary 12 000-picture bubble-chamber exposure. We find σinel=32.8±1.0 mb; the low moments of the multiplicity distribution for negative particles are 〈n−〉=3.50±0.07, D−=2.37±0.05, f2−=2.1±0.2, and f3−=0.1±0.9. We also present updated results at 102 GeV/c.

3 data tables

SUPERCEDES PRELIMINARY RESULTS IN J. W. CHAPMAN ET AL., PRL 29, 1686 (1972).

No description provided.

FIT TO ELASTIC DIFFERENTIAL CROSS SECTION FOR 0.05 < -T < 0.7 GEV**2.


POSITIVE PION PHOTOPRODUCTION FROM HYDROGEN FOR INCIDENT PHOTON ENERGIES 300-MEV - 750-MeV

Betourne, C. ; Bizot, J.C. ; Perez-y-Jorba, J.P. ; et al.
Phys.Rev. 172 (1968) 1343-1353, 1968.
Inspire Record 52601 DOI 10.17182/hepdata.29563

The differential cross section for the reaction γ+p→π+n was measured at 19 photon energies between 300 and 750 MeV in the laboratory frame, for pion angles between 0° and 130° in the c.m. system. The pions were analyzed in angle and momentum with a magnetic spectrometer and detected by a counter telescope. The 0° measurements could be achieved, in spite of the excessive positron rate, owing to a mass-spectrometer arrangement. No direct indication for the electromagnetic excitation of the P11 resonance (1466 MeV) was found. Comparison is made with theoretical calculations of π+ photoproduction.

21 data tables

No description provided.

No description provided.

No description provided.

More…

PROTON FORM-FACTORS FROM PROTON OBSERVATION

Frerejacque, Daniel ; Benaksas, David ; Drickey, Darrell James ;
Phys.Rev. 141 (1966) 1308-1312, 1966.
Inspire Record 48595 DOI 10.17182/hepdata.26652

A determination of the electric and magnetic form factors of the proton has been made by studying the elastic scattering of electrons from a polyethylene target by observation of the recoiling proton at 0° and 30° for values of q2 between 1 and 1.8 F−2. From these measurements we have deduced the charge radius Rc and the magnetic radius Rm of the proton and find equality within the experimental errors (Rc=0.800±0.025 F; Rm=0.810±0.029 F).

8 data tables

No description provided.

No description provided.

No description provided.

More…