Bellettini, G.
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The $\rho^\prime$ (1600) in the Reaction $\gamma p \to \pi^+ \pi^- \pi^0 \pi^0 p$ at Photon Energies of 20-{GeV} to 70-{GeV}

The Omega Photon collaboration Atkinson, M. ; Axon, T.J. ; Barberis, D. ; et al.
Z.Phys.C 26 (1985) 499, 1985.
Inspire Record 202941 DOI 10.17182/hepdata.15774

The reactionγp→π+π−π0π0p (excludingωπ0 production) has been studied for photon energies in the range 20–70 GeV. A peak is seen in the 4π mass spectrum at ∼1.66 GeV with a width of ∼0.3 GeV which is identified with theρ′(1600). Maximum likelihood fits show that the peak is dominantly inρ±π∓π0 withB(ρ′→ρ0π0π0)/B(ρ′→ρ±π∓π0)<0.1. This indicates anI=1ρπ final-state interaction. However, no evidence is found for any resonant ρπ state such as anA1 orπ′.

2 data tables
Table 1

AFTER OMEGA EXCLUSION.

Table 2

ERROR IS DOMINANTLY SYSTEMATIC.


The $Q^2$ and Transverse Momentum Dependence of Jet Production in Photon-photon Interactions

The PLUTO collaboration Berger, Christoph ; Deuter, A. ; Genzel, H. ; et al.
Z.Phys.C 26 (1984) 191, 1984.
Inspire Record 203794 DOI 10.17182/hepdata.16196

We present an experimental study of jetproduction in photon-photon interactions for 0.1≲Q2≲120 GeV2 and jet transverse momentum,pT, up to 5 GeV/c. At alQ2, the data show a highpT, tail, characteristic of a point-like interaction. The jet production cross-section approaches the quarkparton model (QPM) expectation as either jetpT orQ2 increases. Overall, the data are well described in both total cross-section and event topology by the sum of a vector-dominance model and a point-like interaction, represented by the QPM.

1 data table
Table 1

No description provided.


Upper Limits on the Production Rate of the Decuplet Baryons $\Delta$ and $\Sigma^*$ in $e^+ e^-$ Annihilation at 34.4-{GeV}

The TASSO collaboration Althoff, M. ; Braunschweig, W. ; Kirschfink, F.J. ; et al.
Z.Phys.C 26 (1984) 181, 1984.
Inspire Record 203142 DOI 10.17182/hepdata.16197
2 data tables
Table 1

UPPER LIMITS FOR DEL(1232)++ PRODUCTION.

Table 2

UPPER LIMITS FOR SIG(1385)+- PRODUCTION.


Charged Charm Production in Proton - Emulsion Interactions at 400-{GeV}/$c$

The Aligarh-Bombay-Chandigarh-Jammu-Varanasi collaboration Aziz, T. ; Ahmad, S. ; Ahrar, H. ; et al.
Z.Phys.C 27 (1985) 325, 1985.
Inspire Record 206837 DOI 10.17182/hepdata.18517

A study of charged charm production is made at 400 GeV incident energy of protons in nuclear emulsion. A total of 7005 primary stars have been scrutinized to look for charm particle decays in the forward cone within a decay distance of 100–1,000 μm (3,056 stars) and 100–2,000 μm (3,949 stars). In all 10 charm candidates decaying to 3 charged particles plus neutrals have been observed. Background due to secondary interactions for events of such topology is estimated to be ≈3. Background due to strange particle decays is estimated to be negligible. The rest of the events are attributed toΛc+ andD± decays. This leads to a value of 91±35 μb/nucleon for the total charged charm production cross section. Using production cross section forD± from other experiments we obtainΛc+ production cross section as 62±27 μb/nucleon. Two cases of pair production of charm have been seen.

2 data tables
Table 1

Axis error includes +- 0.0/0.0 contribution (NOT GIVENDECAY-BR(BRN=D+ --> 3CHARGED (NEUTRALS), BR=0.5)//DECAY-BR(BRN=D- --> 3CHARGED (NEUTRALS), BR=0.5)//DECAY-BR(BRN=LAMBDA/C+ --> 3CHARGED (NEUTRALS), BR=0.6)).

Table 2

Axis error includes +- 0.0/0.0 contribution (NOT GIVENDECAY-BR(BRN=D+ --> 3CHARGED (NEUTRALS), BR=0.5)//DECAY-BR(BRN=D- --> 3CHARGED (NEUTRALS), BR=0.5)//DECAY-BR(BRN=LAMBDA/C+ --> 3CHARGED (NEUTRALS), BR=0.6)).


Inclusive $K^0_S$, $\Lambda$ and $\bar{\Lambda}$ Production in 360-{GeV}/$c p p$ Interactions Using the European Hybrid Spectrometer

The EHS-RCBC & Bombay-CERN-Genoa-Innsbruck-Japan-Madrid-Mons-Rutgers-Serpukhov-Tennessee-Vienna collaborations Asai, M. ; Bailly, J.L. ; Banerjee, S. ; et al.
Z.Phys.C 27 (1985) 11, 1985.
Inspire Record 202938 DOI 10.17182/hepdata.16100

Results on cross sections, longitudinal and transverse momentum distributions forKs/0, Λ and\(\bar \Lambda \) production in 360GeV/cpp interactions are presented as obtained from EHS equipped with the Rapid Cycling Bubble Chamber (RCBC). The Λ and\(\bar \Lambda \) polarizations are measured. The cross section for the diffractive components is given using the recoil spectrum. The data are discussed with respect to charm production.

1 data table
Table 1

No description provided.


A Measurement of the Electroweak Induced Charge Asymmetry in e+ e- ---> B anti-B

The JADE collaboration Bartel, W. ; Becker, L. ; Bowdery, C. ; et al.
Phys.Lett.B 146 (1984) 437-442, 1984.
Inspire Record 203144 DOI 10.17182/hepdata.6565

The forward-backward charge asymmetry for the process e + e − → b b ̄ → μ ± + hadrons has been measured using the JADE detector at PETRA. An asymmetry of (−22.8 ± 6.0 ± 2.5)% was observed at an average center of mass energy of 34.6 GeV. For comparison, an asymmetry of −25.2% is expected on the basis of the standard Glashow-Salam-Weinberg model.

4 data tables
Table 1

THE VALUE OF CONST HAVE BEEN RESCALED TO DEFINITION I3(Q) = 1/2 BY OPY.

Table 2

No description provided.

Table 3

No description provided.

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rivet Analysis
A Measurement of Energy-energy Correlations in $e^+ e^- \to$ Hadrons at $\sqrt{s}=29$-{GeV}

Fernandez, E. ; Ford, William T. ; Qi, N. ; et al.
Phys.Rev.D 31 (1985) 2724, 1985.
Inspire Record 202924 DOI 10.17182/hepdata.23586

The energy-energy correlation cross section for hadrons produced in electron-positron annihilation at a center-of-mass energy of 29 GeV has been measured with the MAC detector at SLAC. The result is corrected for the effects of detector resolution, acceptance, and initial-state radiation. The correlation is measured in two independent ways on the same data sample: the energy weights and angles are obtained either from the energy flow in the finely segmented total absorption calorimeters or from the momenta of charged tracks in the central drift chamber. This procedure helps reduce systematic errors by cross-checking the effects of the detector on the measurement, particularly important because the corrections depend on complex Monte Carlo simulations. The results are compared with the predictions of Monte Carlo models of complete second-order perturbative quantum chromodynamics and fragmentation, with the following conclusions: (1) fitting the asymmetry for large correlation angles gives values for αS of 0.120±0.006 in perturbation theory, 0.185±0.013 in the Lund string model, and values which vary from 0.105 to 0.140 (±0.01) in the incoherent jet models, depending on the gluon fragmentation scheme and the algorithm used for momentum conservation; and (2) the string fragmentation model provides a satisfactory description of the measured energy-energy correlation cross section, whereas incoherent jet formation does not.

1 data table
Table 1

VALUES FOR THE ASSYMETRY ARE GIVEN ALSO.


Search for Anti-proton - Nucleus States With ($\bar{p}$, $p$) Reactions

Garreta, D. ; Birien, P. ; Bruge, G. ; et al.
Phys.Lett.B 150 (1985) 95-99, 1985.
Inspire Record 203156 DOI 10.17182/hepdata.49641

We have studied (p̄, p) reactions on 12 C , 63 Cu, and 209 Bi to search for possible nuclear states formed ny antiprotons and nuclei. The experiments used the 180 MeV antiproton beam from LEAR, and the high-resolution magnetic spectrometer, SPES II, to detect the outgoing protons. No evidence of antiproton-nucleus states was found. The gross features of the proton spectra are reasonably well described by intranuclear cascade model calculations, which consider proton emission following antiproton annihilations in the target nucleus.

1 data table
Table 1

Parameters resulting from the best fits to the proton spectra with the expression D2(SIG)/D(OMEGA)/D(E) = CONST*SQRT(E)*EXP(-E/SLOPE).


Measurement of the Proton - anti-Proton Total and Elastic Cross-Sections at the CERN SPS Collider

The UA4 collaboration Bozzo, M. ; Braccini, P.L. ; Carbonara, F. ; et al.
Phys.Lett.B 147 (1984) 392-398, 1984.
Inspire Record 203148 DOI 10.17182/hepdata.49643

The proton-antiproton total cross section was measured at the CM energy √s = 546 GeV . The result is σ tot = 61.9± 1.5 mb . The ratio of the elastic to the total cross section is σ e ℓ / σ tot = 0.215±0.005. A comparison to the lower energy data shows that the increase of the total cross section with energy is very close to a log 2 s behaviour.

2 data tables
Table 1

CROSS SECTIONS ASSUMING RHO = 0.15.

Table 2

RATIO OF ELASTIC TO TOTAL CROSS SECTION.


MOMENTUM AND ANGULAR DISTRIBUTIONS OF CHARGED SECONDARIES IN 40-GeV/c pi- A INTERACTIONS WITH SINGLE PARTICLE HIGH P(T) TRIGGER

The Berlin-Budapest-Dubna-Prague-Sofiya-Tbilisi-Warsaw collaboration Adam, G. ; Bannikov, A.V. ; Bohm, J. ; et al.
JINR-E1-84-442, 1984.
Inspire Record 203314 DOI 10.17182/hepdata.9861

None

6 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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