Giacomelli, G.
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High-Momentum Hadrons from e+ e- Reactions: Spectra, Particle Ratios, and Multiplicities

Atwood, T.L. ; Barnett, B.A. ; Cavalli-Sforza, M. ; et al.
Phys.Rev.Lett. 35 (1975) 704, 1975.
Inspire Record 100695 DOI 10.17182/hepdata.21140

We present results from a study of high-momentum inclusive hadron production in electron-positron interactions at s=3.8 and 4.8 GeV. Comparison of the momentum spectra at these energies shows no scaling violation in the region x(=EEbeam)>0.7. At s=4.8 GeV the Kπ ratio for hadrons with momenta >1.1 GeV/c is 0.27±0.08, and the average number of charged hadrons is 3.6±0.3 for those events which have at least one charged hadron with momentum greater than 1.1 GeV/c.

1 data table
Table 1

No description provided.


The Quantum Numbers and Decay Widths of the psi-prime (3684)

Luth, V. ; Boyarski, A. ; Lynch, H.L. ; et al.
Phys.Rev.Lett. 35 (1975) 1124-1126, 1975.
Inspire Record 100636 DOI 10.17182/hepdata.21229

Cross sections for e+e−→hadrons, e+e−, and μ+μ− near 3684 MeV are presented. The ψ(3684) resonance is established as having the assignment JPC=1−−. The mass is 3684 ± 5 MeV. The partial width for decay to electrons is Γe=2.1±0.3 keV and the total width is Γ=228±56 keV.

1 data table
Table 1

No description provided.


Photoproduction of the psi (3100) Meson at 11-GeV

Gittelman, B. ; Hanson, K.M. ; Larson, D. ; et al.
Phys.Rev.Lett. 35 (1975) 1616, 1975.
Inspire Record 99727 DOI 10.17182/hepdata.21158

The photoproduction of the ψ(3100) meson from a beryllium target has been measured using an 11.8-GeV bremsstrahlung beam. The energy and angular dependence of the measured spectra may be obtained from an elastic nucleon cross section of the form dσdt=(1.01±0.20)exp[(1.25±0.20)t] nb/GeV2. This cross section is exceedingly small in comparison with those of the other vector mesons.

1 data table
Table 1

ELECTRON PAIR PRODUCTION FROM BERYLLIUM TARGET. ELASTIC CROSS SECTION VALUE ALLOWS FOR SYSTEMATIC UNCERTAINTIES AND POSSIBLE INELASTIC CONTRIBUTIONS. -TMIN = 0.41 GEV**2.


Evidence for anomalous lepton production in e+ e- annihilation.

Perl, Martin L. ; Abrams, G.S. ; Boyarski, A. ; et al.
Phys.Rev.Lett. 35 (1975) 1489-1492, 1975.
Inspire Record 100634 DOI 10.17182/hepdata.21164

We have found events of the form e++e−→e±+μ∓+missingenergy, in which no other charged particles or photons are detected. Most of these events are detected at or above a center-of-mass energy of 4 GeV. The missing-energy and missing-momentum spectra require that at least two additional particles be produced in each event. We have no conventional explanation for these events.

1 data table
Table 1

X IN RE INCLUDES TWO OR MORE UNDETECTED PARTICLES.


Search for xi* Resonances in 2.87-GeV/c K- n Interactions

Briefel, E. ; Gourevitch, S.A. ; Kirsch, L. ; et al.
Phys.Rev.D 12 (1975) 1859, 1975.
Inspire Record 99862 DOI 10.17182/hepdata.24850

We report on a search for Ξ* production in the mass range 1.5-2.0 GeV / c2 in K−n interactions at 2.87 GeV / c. Upper limits on Ξ* production cross sections, as well as reaction cross sections for those final states in which Ξ*'s may be observed, are presented. In particular, an upper limit of 5.4 μb is placed on production of an isospin-−32 Ξ*−−.

3 data tables
Table 1

CROSS SECTIONS ARE QUOTED FOR THE SAME FINAL STATE DERIVED FROM DIFFERENT TOPOLOGIES.

Table 2

UPPER LIMITS AT 90 PCT CONFIDENCE LEVEL FOR RESONANCE ABOVE SMOOTH BACKGROUND.

Table 3

No description provided.


Pi- p Elastic Scattering at 3.92-GeV/c

Alitti, J. ; Bouchez, J. ; Devenski, P. ; et al.
Nuovo Cim.A 33 (1976) 160, 1976.
Inspire Record 100941 DOI 10.17182/hepdata.37676

π−p elastic scattering is studied at an incident π− beam momentum of 3.92 GeV/c. From the analysis of about 38 000 elastic events we give the differential cross-section for −t>0.06 (GeV)2. The known structures at −t ≈ 0.8 and 2.8 (GeV)2 are seen. An additional possible structure is present in the backward hemisphere.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Study of photoproduction on hydrogen in a streamer chamber with tagged photons for 1.6 GeV $ < E_\gamma <$ 6.3 GeV Topological and reaction cross sections

The Aachen-Hamburg-Heidelberg-Munich collaboration Struczinski, W. ; Dittmann, P. ; Eckardt, V. ; et al.
Nucl.Phys.B 108 (1976) 45-74, 1976.
Inspire Record 100089 DOI 10.17182/hepdata.35779

We have studied photoproduction using a 1 m streamer chamber at DESY and a tagged photon beam with an energy range of 1.6 GeV < E γ < 6.3 GeV. We analysed approximately 30 000 events and report topological, channel and resonance production cross sections for a large number of reactions with three and five outgoing charged particles.

29 data tables
Table 1

CHANNEL CROSS SECTIONS FOR 3, 5 AND 7 PRONG REACTIONS.

Table 2

'PARAMETRIZATION'.

Table 3

'INTERFERENCE'.

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Study of pi- n and pi- C-12 Interactions Involving Strange Particles at the Momentum of 40-GeV/c

Angelov, N. ; Vishnevskaya, K.P. ; Grishin, V.G. ; et al.
Yad.Fiz. 24 (1976) 732-741, 1976.
Inspire Record 100544 DOI 10.17182/hepdata.18228

None

5 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Two Particle Correlations in Inclusive and Semiinclusive pi- p Reactions at 200-GeV/c

Biswas, N.N. ; Bishop, J.M. ; Cason, N.M. ; et al.
Phys.Rev.Lett. 35 (1975) 1059, 1975.
Inspire Record 2906 DOI 10.17182/hepdata.3351

Significant two-particle correlations of dynamical origin are observed in 200 GeV/c π−p inclusive interactions. This is demonstrated by comparison with kinematic correlations calculated from an independent-particle-emission model. Two distinct correlation types are observed: (a) unlike-particle correlations with correlation length ∼ 1.3 rapidity units independent of azimuthal separation, and (b) like-particle correlations with correlation length ∼ 0.4 rapidity units which are observed only for small azimuthal separations.

12 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Observation of High Mass mu+ mu- Pairs at the ISR

Nagy, E. ; Regler, M. ; Schmidt-Parzefall, W. ; et al.
Phys.Lett.B 60 (1975) 96-100, 1975.
Inspire Record 100337 DOI 10.17182/hepdata.27713

Observation of 16 μ + μ − pairs of invariant mass greater than 2.7 GeV/ c 2 in the reaction pp → μ + μ − + anything at s = 52 GeV at the CERN Intersecting Storage Rings (ISR) is reported. These events can be interpreted as originating from J(3.1) decay into μ + μ − . Their p T distribution suggests a hadronic production. The cross section for J production is given and compared to the cross section for single lepton production. We conclude that J(3.1) production cannot fully account for single lepton production.

1 data table
Table 1

No description provided.