Anomalous Production of High-Energy Muons in e+ e- Collisions at 4.8-GeV

Cavalli-Sforza, M. ; Goggi, G. ; Mantovani, G.C. ; et al.
Phys.Rev.Lett. 36 (1976) 558, 1976.
Inspire Record 100744 DOI 10.17182/hepdata.21103

In view of the possible production of heavy leptons or charmed states in e+e− collisions, we searched for anomalous muons with momenta pμ≳1 GeV/c. The inclusive cross section for nch>~3 has an upper limit of 96 pb (assuming isotropy). For nch=2 and noncoplanarity > 20°, an excess of muonic events is observed, corresponding to (dσdΩ)|90°=23−9+12 pb/sr; the probability that known processes produce the observed events is 2×10−4.

1 data table

No description provided.


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

No description provided.


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

No description provided.

No description provided.

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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

X IN RE INCLUDES TWO OR MORE UNDETECTED PARTICLES.


Version 2
Measurements of sigma(e+ e- --> mu+- mu-+) in the energy range 1.2-GeV to 3.0-GeV.

Alles-Borelli, V. ; Bernardini, M. ; Bollini, D. ; et al.
Phys.Lett.B 59 (1975) 201, 1975.
Inspire Record 99248 DOI 10.17182/hepdata.27778

The analysis of 1466 events of the type e + e − → μ ± μ ± , in the time-lifke range from 1.44 to 9.00 GeV 2 , sh that the absolute value of the cross-section and its energy dependence follow QED expectations within (± 3.2%) and (± 1.2%), respectively.

1 data table

The cross section of the reaction $e^+ e^- \to \mu^\pm \mu^\mp$ integrated over the experimental apparatus at 14 values of the colliding beam energy $E$ corresponding to total centre-of-mass energy $\sqrt{s}=2E$ from 1.2 to 3.0 GeV.


Dimuon Production by Neutrons

Knapp, B. ; Lee, Won-Yong ; Leung, P. ; et al.
Phys.Rev.Lett. 34 (1975) 1044, 1975.
Inspire Record 2108 DOI 10.17182/hepdata.21935

A very narrow resonance with a mass of 3.1 GeV/c2 is observed in the reaction n+Be→μ++μ−+X. The total cross section for this process, as well as its P⊥2 and x distribution, are given.

1 data table

The cross section per nucleon times the branching ratio.


Photoproduction of Narrow Resonances

Knapp, B. ; Lee, Won-Yong ; Leung, P. ; et al.
Phys.Rev.Lett. 34 (1975) 1040, 1975.
Inspire Record 2411 DOI 10.17182/hepdata.21280

A very narrow resonance with a mass of 3.105 GeV/c2 is observed in the reaction γ+Be→μ++μ−+X. The total cross section for this process, as well as its t distribution, is given.

1 data table

THIS IS CROSS SECTION PER BERYLLIUM NUCLEUS ASSUMING ONLY COHERENT OR QUASI-ELASTIC SCATTERING FROM A SINGLE NUCLEON. FORWARD DIFFERENTIAL CROSS SECTIONS QUOTED IN TABLE 1 OF T. NASH ET AL., PRL 36, 1233 (1976).


Muon-Deuterium Deep Inelastic Scattering

Kim, I.J. ; Entenberg, A. ; Jostlein, H. ; et al.
Phys.Rev.Lett. 33 (1974) 551, 1974.
Inspire Record 1427 DOI 10.17182/hepdata.21238

We have measured deep inelastic muon-deuteron scattering in the range 0.4<Q2<3.4 and 1.6<ν<5.6 GeV. We have extracted the neutron structure function and find that νW2n differs significantly from νW2p, as also found in e−d scattering. To compare μ−d and e−d scattering we form the ratio r(Q2)=(νW2)μd(νW2)ed=N(1+Q2Λ2)−2 and find N=0.925±0.038 and 1Λ2=−0.019±0.016.

1 data table

No description provided.


Observation of single pion production by a weak neutral current.

Barish, S.J. ; Cho, Y. ; Derrick, M. ; et al.
Phys.Rev.Lett. 33 (1974) 448, 1974.
Inspire Record 89586 DOI 10.17182/hepdata.51354

In exposures of the Argonne National Laboratory 12-ft bubble chamber filled with hydrogen and deuterium to a neutrino beam, we have observed events consisting of (1) a single π+ meson originating in the liquid, and (2) a proton with an e+e− pair pointing to it. Only a small fraction of these events can be ascribed to known reactions such as np→nnπ+ and np→npπ0. The remaining events, which correspond to a signal of about 4.5 standard deviations, we ascribe to the reactions νp→νnπ+ and νpπ0.

1 data table

No description provided.


Approximate Scaling of Multiplicity Distributions as a Function of Missing Mass

Barshay, S. ; Engelmann, R. ; Kafka, T. ; et al.
Phys.Rev.Lett. 32 (1974) 1390, 1974.
Inspire Record 1032 DOI 10.17182/hepdata.21933

Data from p+p→p+X at 102, 205, and 405 GeV and from π−+p→p+X at 205 GeV exhibit an approximate scaling property in the charged-prong multiplicity distributions as a function of the missing mass for the range 5<~MX<~13 GeV.

1 data table

No description provided.