Ershov, A.
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Production of $\rho^\pm$, $G^\pm$(1700), $A2^\pm$, $K^{*\pm}$(890) and $K^{*\pm}$(1420) at 50-{GeV}/c

Delfosse, A. ; Dorsaz, P.A. ; Extermann, P. ; et al.
Nucl.Phys.B 183 (1981) 349-366, 1981.
Inspire Record 170363 DOI 10.17182/hepdata.34280

Mesons decaying into π 0 or η and one charged meson were studied using a liquid-argon calorimeter in a non-magnetic double-arm spectrometer. Cross sections and energy dependences are presented. The ϱ ± production mechanisms are discussed in detail: ω and π exchange contribute the largest fractions, but also A 2 exchange is present. ϱ ± production by ω exchange is shown to follow the energy behaviour predicted by the Regge trajectory α ω ( t ) = 0.4 − | t |.

2 data tables
Table 1

Axis error includes +- 0.0/0.0 contribution (13 TO 25////STATISTICAL ERRORS ARE SMALLER THAN THE SYSTEMATIC ERRORS).

Table 2

No description provided.


Lepton Pair Production and Search for a New Heavy Lepton in $e^+ e^-$ Annihilation

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Grigull, R. ; et al.
Phys.Lett.B 99 (1981) 489-494, 1981.
Inspire Record 164302 DOI 10.17182/hepdata.27110

We have measured the reaction ee → μμ and ee → ττ at center of mass energies from 9.4 to 31.6 GeV. The production cross sections are in agreement with the predictions of quantum electrodynamics, resulting in cutoff parameter limits of 70–100 GeV at 95% c.l. The branching ratio for τ → μν ν has been determined as [1.78 ± 2.0 (statist.) ± 1.8(syst.)]% The existence of a new sequential heavy lepton with a mass <14.5 GeV is excluded at 95% c.l.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Evidence for a New Pseudoscalar Meson

Bonesini, M. ; Donald, R.A. ; Edwards, D.N. ; et al.
Phys.Lett.B 103 (1981) 75-78, 1981.
Inspire Record 170357 DOI 10.17182/hepdata.31149

Performing a PWA of the π − π − π + system over the −t p/p range 0.2 to 0.4 GeV 2 we find evidence for a J P = 0 − , J G =1 − meson of mass 1342 ± 20 MeV and width 220 ±70 MeV decaying into ϵπ. This state is produced by natural parity exchange with a slope similar to that of elastic scattering. It can be interpreted as a radial excitation of the π meson (π′).

1 data table
Table 1

INTEGRATING EXTRAPOLATED EXPONENTIAL FIT GIVES A TOTAL CROSS SECTION OF ABOUT 54 MUB.


Observation of a $K \bar{K}$ Enhancement at 1.85-{GeV} in the Reaction $K^- P \to K \bar{K} \Lambda$ at 8.25-{GeV}/c

The BIRMINGHAM-CERN-GLASGOW-MICHIGAN STATE-PARIS collaboration Al- Harran, S. ; Amirzadeh, J. ; Baubillier, M. ; et al.
Phys.Lett.B 101 (1981) 357-360, 1981.
Inspire Record 170589 DOI 10.17182/hepdata.31206

In a high statistics ( ∼150 eV μb ) bubble chamber experiment on K − p interactions at 8.25 GeV c , the study of the reaction K − p → KK Λ provides evidence for an enhancement in the KK system with a mass of (1850 ± 10) MeV and a width of (80 −30 +40 ) MeV. Its possible identification with the missing isosinglet of the 3 − nonet is discussed. A K ∗ K decay mode is also observed.

1 data table
Table 1

No description provided.


Hadronic Cross-section in $e^+ e^-$ Annihilation From 1.45-{GeV} to 1.80-{GeV}

Esposito, B. ; Marini, A. ; Piano Mortari, Giovanni ; et al.
Lett.Nuovo Cim. 30 (1981) 65-71, 1981.
Inspire Record 170172 DOI 10.17182/hepdata.37368

None

2 data tables
Table 1

CROSS SECTION EXCLUDES ANY CONTRIBUTION FROM TWO-BODY FINAL STATES (PI+ PI- AND K+ K-).

Table 2

CHARGED AND NEUTRAL MULTIPLICITIES.


DETERMINATION OF LARGE ANGLE CROSS-SECTIONS FOR pi- p ---> pi- DELTA+ AT 5-GeV/c

Carlson, P.J. ; Johansson, K.E. ; Eide, A. ; et al.
Nuovo Cim.A 62 (1981) 196, 1981.
Inspire Record 164127 DOI 10.17182/hepdata.37544

We have measured the differential cross-section for the process π-+p → π- + Δ+ in thet interval (1.74/3.5) (GeV/c)2 at 5 GeV/c. At the largestt-values, the cross-sections have the same magnitude as the π-p elastic cross-sections.

1 data table
Table 1

No description provided.


COULOMB - NUCLEAR INTERFERENCE IN PROTON DEUTERIUM ELASTIC SCATTERING AT 600-MEV AND THE REAL PART OF P N SCATTERING AMPLITUDE

Gardes, J. ; Jargeaix, B. ; Lefort, A. ; et al.
Nuovo Cim.A 61 (1981) 121-132, 1981.
Inspire Record 170137 DOI 10.17182/hepdata.37549

The differential cross-sections for the elastic scattering of protons on deuterium have been measured at 600 MeV in the |t| range between 0.003 and 0.030 (GeV/c)2. The results are analysed by using the Bethe and Glauber formalisms taking into account spin effects in deuterium wave function and nucleon-nucleon amplitudes. The ratio between the real and the imaginary parts of the spin-independent protonneutron amplitude αpn deduced from dispersion calculations and phase shift analysis is compared with experimental results.

1 data table
Table 1

No description provided.


rivet Analysis
Charged Hadron Production in $e^+ e^-$ Annihilation in the $\Upsilon$ and $\Upsilon^\prime$ Region

The LENA collaboration Niczyporuk, B. ; Zeludziewicz, T. ; Chen, K.W. ; et al.
Z.Phys.C 9 (1981) 1, 1981.
Inspire Record 164397 DOI 10.17182/hepdata.1354

Charged hadron production ine+e− annihilation is studied in the 7 to 10 GeV CM energy region and at the Υ (9.46) and Υ′ (10.01) resonances with the LENA detector at DORIS. The statistical moments of the charged multiplicities are studied. The data show KNO scaling behaviour and suggest the presence of long range correlations. An average charged multiplicityrise of Δn(Υ)=0.55±0.19 and Δn(Υ′)=1.26±0.29 over the continuum is observed for the Υ and Υ′ direct decays. The jet structure of the Υ and Υ′ direct decays is investigated using the charged particles. The polar angular distributions of the jet axis behave like 1+α(T) cos2θ with 〈α(T)〉Υ=0.7±0.3 and 〈α(T)〉Υ′=0.6±0.4. The 〈α(T)〉Υ value is in agreement with the QCD vector gluon assignment and excludes scalar gluons by more than four standard deviations.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


QUASIELASTIC OMEGA PHOTOPRODUCTION AT 50-GEV - 130-GEV

Breakstone, A.M. ; Cheng, D.C. ; Dorfan, D.E. ; et al.
Phys.Rev.Lett. 47 (1981) 1782-1785, 1981.
Inspire Record 173081 DOI 10.17182/hepdata.20625

A study of quasielastic ω photoproduction where the ω was detected in its π0γ decay mode is reported. The recoil proton's angle was detected with a nonmagnetic spectrometer allowing a full reconstruction of the final state. Differential cross sections for 0.1<|t|<1.2 GeV2 are presented, providing a test of the vector-meson dominance model over an extensive energy and momentum transfer range. The shape of the differential cross section agrees with that seen in both elastic γp and πp scattering as expected from this model.

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

More…

Elastic Photon Proton Scattering in the 50-{GeV} - 130-{GeV} Range

Breakstone, A.M. ; Cheng, D.C. ; Dorfan, D.E. ; et al.
Phys.Rev.Lett. 47 (1981) 1778-1781, 1981.
Inspire Record 173082 DOI 10.17182/hepdata.20627

In the tagged-photon beam at Fermilab, differential cross sections were measured for the elastic scattering of photons on a liquid-hydrogen target. The diffractive forward peak was measured for photon energies between 50 and 130 GeV and |t| values between 0.07 and 1.20 (GeV/c)2. The shape of the diffraction peak is similar to that seen in π−p scattering. The magnitude is that predicted by the optical theorem.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.