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rivet Analysis
Total Cross-section for Hadron Production by $e^+ e^-$ Annihilation at Center-of-mass Energies Between 3.6-{GeV} and 5.2-{GeV}

The DASP collaboration Brandelik, R. ; Braunschweig, W. ; Martyn, H.U. ; et al.
Phys.Lett.B 76 (1978) 361, 1978.
Inspire Record 129715 DOI 10.17182/hepdata.27431

The total cross section for e + e − annihilation into hadronic final states between 3.6 and 5.2 GeV was measured by the nonmagnetic inner detector of DASP, which has similar trigger and detection efficiencies for photons and charged particles. The measured difference in R = σ had / σμμ between 3.6 GeV and 5.2 GeV is ΔR = 2.1 ± 0.3. We observe three peaks at cm energies of 4.04, 4.16 and 4.417 GeV, the parameters of which, when interpreted as resonances, are given.

2 data tables match query
Table 1

EXCLUDING CONTRIBUTION OF TAU HEAVY LEPTON.

Table 2

INCLUDING CONTRIBUTION OF TAU HEAVY LEPTON.


Backward Enhancement in the a1 Region and a2 Production in the Region pi- p --> p(f) pi+ pi- pi- at 9-GeV/c and 12-GeV/c

Ferrer, A. ; Bouquet, B. ; D'Almagne, B. ; et al.
Phys.Lett.B 74 (1978) 287-291, 1978.
Inspire Record 134669 DOI 10.17182/hepdata.27446

Results on backward (3 π ) - system produced in π - p→p f π + π - π - reaction at 9 and 12 GeV/ c are given. The ϱ 0 π - mass spectra show two clear signals at 1050 MeV (A 1 region) and 1303 MeV (A - 2 ). The width of the enhancement in the A 1 region (195±32 MeV) is narrower than found in diffractive experiments. Total backward cross sections for those signals are of the same order of magnitude (∼0.5 μb).

1 data table match query
Table 1

No description provided.


Evidence for Two Narrow p anti-p Resonances at 2020-MeV and 2200-MeV

The CERN-College de France-Ecole Poly-Orsay collaboration Benkheiri, P. ; Boucrot, J. ; Bouquet, B. ; et al.
Phys.Lett.B 68 (1977) 483, 1977.
Inspire Record 119491 DOI 10.17182/hepdata.27541

From the study of the reaction π − p→p F p p π − using a fast proton (p F ) trigger device in the CERN Omega spectrometer, we find evidence for two narrow p p states produced mainly in association with a Δ° (1232) and a N° (1520). The statistical significance of each peak is greater than 6 standard deviations. Masses and natural widths of these resonances are respectively M = 2020 ± 3 MeV , Λ 1 = 24 ± 12 MeV and M 2 = 2204 ± 5 MeV, Λ 2 = 16 −16 +20 MeV. Our data are consistent with a small production of the narrow ∼ 1935 MeV resonance already reported. Production cross sections for these new p p resonances are given.

1 data table match query
Table 1

ERRORS TAKE INTO ACCOUNT STATISTICAL ERRORS AND BACKGROUND SUBTRACTION UNCERTAINTY BUT NOT ACCEPTANCE CORRECTIONS UNCERTAINTY OF 15 PCT.


Azimuthal Asymmetry in Inclusive Hadron Production by e+ e- Annihilation

Schwitters, R. ; Boyarski, A. ; Breidenbach, Martin ; et al.
Phys.Rev.Lett. 35 (1975) 1320, 1975.
Inspire Record 100683 DOI 10.17182/hepdata.21192

We have observed an azimuthal asymmetry in inclusive hadron production by e+e− annihilation at the center-of-mass energy s=7.4 GeV. The asymmetry is caused by the polarization of the circulating beams in the storage ring and allows separate determination of the transverse and longitudinal structure functions. We find that transverse production dominates for x>0.2 where x is the scaling variable 2ps.

3 data tables match query
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


Measurement of e+ e- ---> e+ e- and e+ e- ---> mu+ mu- at SPEAR

Augustin, J.E. ; Boyarski, A. ; Breidenbach, Martin ; et al.
Phys.Rev.Lett. 34 (1975) 233, 1975.
Inspire Record 91755 DOI 10.17182/hepdata.21210

The reactions e+e−→e+e− and e+e−→μ+μ− have been measured at center-of-mass energies 3.0, 3.8, and 4.8 GeV and production angles of 50°<θ<130° over all azimuthal angles. Agreement with quantum electrodynamics is excellent. New limits for cutoff parameters in quantum-electrodynamic-breakdown models are given.

2 data tables match query
Table 1

No description provided.

Table 2

No description provided.


A measurement of elastic pion-proton scattering at 50 gev

Derevchekov, A.A. ; Golovin, N.I. ; Khodirev, Y.C. ; et al.
Phys.Lett.B 48 (1974) 367-370, 1974.
Inspire Record 95356 DOI 10.17182/hepdata.27998

We have measured elastic pion-proton scattering in a 50 GeV/ c π − beam at the 76 GeV proton synchrotron in Serpukhov. Data are presented for four-momenta transfer squared in the range 0.03 < t < 0.4 (GeV/ c ) 2 .

1 data table match query
Table 1

SLOPE IS 9.1, +0.2, -0.4 GEV**-2 (INCLUDING SYSTEMATIC ERRORS).


A Study of massive electron pairs and associated particles produced at the CERN ISR

The CERN-Michigan State-Oxford-Rockefeller collaboration Angelis, A.L.S. ; Basini, G. ; Besch, H.J. ; et al.
Nucl.Phys.B 348 (1991) 1-22, 1991.
Inspire Record 298427 DOI 10.17182/hepdata.33054

A sample of 105 e + e − events with an invariant mass greater than 11 GeV/ c 2 produced in pp collisions at a center-of-mass energy of 62.3 GeV is discussed. Cross sections are presented as a function of mass and transverse momentum. The multiplicity, transverse momentum, and azimuthal dependence of associated particles are also studied.

3 data tables match query
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


Lambda Production in the Fragmentation Processes Target Fragmentation of Proton Into Lambda and Beam Fragmentation of K- Into Lambda at 4.25-GeV/c

The Amsterdam-CERN-Nijmegen collaboration Blokzijl, R. ; Bergé, J P ; De Groot, A J ; et al.
Nucl.Phys.B 98 (1975) 401-417, 1975.
Inspire Record 99057 DOI 10.17182/hepdata.31899

In the reaction K − +p→ Λ +X at 4.25 GeV/ c both the target fragmentation of the proton into lambda and the beam fragmentation of kaon into lambda have been studied. The sample consists of 21 000 Λ events with t >−1.0 (GeV/ c ) 2 and 9000 Λ events with u > −1.0 (GeV/ c ) 2 . Abundant π 0 and meson resonance production for residual masses M x <1.1 GeV/ c 2 is observed. In the t -channel of am effective exchange trajectory is deduced. which lies between the K and K(890) trajectories. In the u -channel the effective exchange trajectory is in good agreement with a nucleon trajectory. The extrapolated average pion multiplicities of the residual mass system in the t -channel are in very good agreement with the values measured in antiproton-proton annihilations at rest.

3 data tables match query
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


First measurement of D (0n 0n) in anti-p p elastic scattering

Kunne, R.A. ; Beard, C.I. ; Birsa, R. ; et al.
Phys.Lett.B 261 (1991) 191-196, 1991.
Inspire Record 316076 DOI 10.17182/hepdata.29400

The depolarization parameter D onon in p p elastic scattering has been measured at LEAR for thirteen momenta between 679 and 1550 MeV/c in the backward angular region. Striking disagreement with theoretical models is observed.

10 data tables match query
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

More…

Anti-p p annihilations at rest. the k anti-k omega channel. mass, width and branching ratio of the omega meson

Bizzari, R. ; Montanet, L. ; Nilsson, S. ; et al.
Nucl.Phys.B 27 (1971) 140-148, 1971.
Inspire Record 68763 DOI 10.17182/hepdata.33708

Data on p p annihilations at rest into K 1 0 K 1 0 ω 0 and K + K − ω 0 are discuss New measurements for the mass, the width and the branching ratio of the ω 0 are presented. Evidence for quasi two-body annihilations p p → ϕπ, p ̄ p → S ∗ π is discussed.

1 data table match query
Table 1

PRODUCTION RATE FOR ANNIHILATION AT REST.