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CHARGED HADRON PRODUCTION IN e+ e- ANNIHILATION AT 29-GeV

The TPC/Two Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Badtke, D.H. ; et al.
Phys.Rev.Lett. 52 (1984) 577, 1984.
Inspire Record 195994 DOI 10.17182/hepdata.20439

The inclusive production cross sections and mean multiplicities of π±, K±, p, and p¯ in e+e− annihilation at a c.m. energy of 29 GeV have been measured with the time-projection chamber at PEP, using ionization energy loss to separate particle types. On average, 10.7±0.6 π±, 1.35±0.13 K±, and 0.60±0.08 p,p¯ are contained in an annihilation event. The fraction of pions among final-state particles decreases from over 95% at 0.3 GeV/c momentum to about 60% at high momentum; the kaon and proton fractions rise correspondingly.

7 data tables

PARTICLE FRACTIONS.

PARTICLE FRACTIONS.

PARTICLE FRACTIONS.

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phi MESON PRODUCTION IN e+ e- ANNIHILATIONS AT 29-GeV

The TPC/Two Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Badtke, D.H. ; et al.
Phys.Rev.Lett. 52 (1984) 2201, 1984.
Inspire Record 200105 DOI 10.17182/hepdata.20445

Production of φ mesons in e+e− annihilation at a center-of-mass energy of 29 GeV has been observed with the time-projection chamber detector at the PEP storage ring. The φ production rate has been measured in the energy range 0.075<x<0.55 (x=2Eφs), giving 0.077±0.012(stat)±0.016(syst) φ's per event. The average value of pt2 relative to the thrust axis is 1.0±0.4 (GeV/c)2.

3 data tables

No description provided.

EXTRAPOLAATION TO ALL X USES LUND MONTE CARLO PREDICTIONS.

ERRORS ARE BOTH STATISTICAL AND SYSTEMATIC. PT IS MEASURED RELATIVE TO THE EVENT THRUST AXIS, AND IS FOUND TO HAVE A MEAN VALUE OF 1.0 +- 0.4 GEV.


PROMPT ELECTRON PRODUCTION IN e+ e- ANNIHILATIONS AT 29-GeV

The TPC/Two Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Badtke, D.H. ; et al.
Z.Phys.C 27 (1985) 39, 1985.
Inspire Record 200040 DOI 10.17182/hepdata.1895

We have measured the inclusive prompt electron cross section over a wide momentum range (P>0.5 GeV/c) with the PEP-4 TPC detector. The semielectronic branching fractions of thec andb quarks are (9.1±0.9 (stat.)±1.3 (syst.))% and (11.0±1.8±1.0)%, respectively. Theb quark fragmentation function peaks at highz with 〈zb〉=0.74±0.05±0.03. The axial couplings to the neutral current areac=2.3±1.4±1.0 for thec quark andab=−2.0±1.9±0.5 for theb quark.

3 data tables

No description provided.

No description provided.

No description provided.


CHARACTERISTICS OF PROTON PRODUCTION IN JETS FROM e+ e- ANNIHILATION AT 29-GeV

The TPC/Two Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Badtke, D.H. ; et al.
Phys.Rev.Lett. 53 (1984) 130, 1984.
Inspire Record 201475 DOI 10.17182/hepdata.20437

Proton production in e+e− annihilation at 29 GeV has been studied with the time projection chamber. Measurements of the dependence of proton fractions on momentum, transverse momentum with respect to the jet axis, hadron multiplicity, and event sphericity are reported. Our results are consistent with the assumption that primary baryons and mesons have similar production spectra, and indicate that protons provide more direct probes of underlying fragmentation phenomena than do pions.

1 data table

No description provided.


A Measurement of the Pion Charge Radius

Amendolia, S.R. ; Badelek, B. ; Batignani, G. ; et al.
Phys.Lett.B 146 (1984) 116-120, 1984.
Inspire Record 201598 DOI 10.17182/hepdata.30511

We report a measurement of the negative pion electromagnetic form factor in the range of space-like four-momentum transfer 0.014 < q 2 < 0.122 (GeV/ c ) 2 . The measurement was made by the NA7 collaboration at the CERN SPS, by observing the interaction of 300 GeV pions with the electrons of a liquid hydrogen target. The form factor is fitted by a pole form with a pion radius of 〈r 2 〈 1 2 = 0.657 ± 0.012 fm.

1 data table

Errors are statistical only.


OBSERVATION OF STRANGENESS CORRELATIONS IN e+ e- ANNIHILATION AT S**(1/2) = 29-GeV

The TPC/Two Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Badtke, D.H. ; et al.
Phys.Rev.Lett. 53 (1984) 2199, 1984.
Inspire Record 204547 DOI 10.17182/hepdata.20411

Correlations in rapidity space are presented for identified π± and K± in e+e− annihilation at 29-GeV c.m. energy. Short-range KK correlations indicate local flavor compensation in the hadronization process. Long-range KK and ππ correlations prove that the initial partons carry flavor. In addition, we observe significant Kπ correlations as a result of heavy-quark decays.

1 data table

No description provided.


EVIDENCE FOR THE F* MESON

The TPC/Two Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Badtke, D.H. ; et al.
Phys.Rev.Lett. 53 (1984) 2465, 1984.
Inspire Record 203890 DOI 10.17182/hepdata.20409

Evidence for a narrow state decaying into an F meson and a photon has been obtained in e+e− annihilation events at 29-GeV c.m. energy. This state lies 139.5 ± 8.3(stat.) ± 9.7(syst.) MeV above the F-meson mass and is consistent with the expected F* meson. The F mesons are identified by a peak in the K+K−Kπ± mass at 1.948±0.028±0.010 GeV.

2 data tables

DATA REQUESTED FROM AUTHORS.

IN (K+K-PI+) THE AUTHORS INCLUDE OTHER DECAY MODES SUCH AS (AK*0 K+),(PHI PI+),(K+ K- PI+,PI0),(K+ K- MU+ NU) WHICH CANNOT BE RESOLVED.


STUDY OF BOSE-EINSTEIN CORRELATIONS IN e+ e- ANNIHILATION AT 29-GeV

The TPC/Two Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Bakken, J.A. ; et al.
Phys.Rev.D 31 (1985) 996, 1985.
Inspire Record 205870 DOI 10.17182/hepdata.23563

Bose-Einstein correlations between like-sign pions have been investigated in e+e− annihilation at √s =29 GeV using the Time Projection Chamber detector at the SLAC e+e− storage ring PEP. The production rate of like-sign pion pairs with small relative momentum is found to be increased by more than 50% over the rate expected for uncorrelated production of pions. From the correlation length, a typical source radius of 0.65 fm is derived. Data are consistent with a spherical shape of the pion source. No dependence of radius or correlation strength on the event multiplicity is observed.

1 data table

No description provided.


CHARM PRODUCTION IN NEUTRON NUCLEON INTERACTIONS

Tzeng, L. ; Mcbride, P.L. ; Cooper, P.S. ; et al.
Phys.Rev.Lett. 55 (1985) 1172-1175, 1985.
Inspire Record 221439 DOI 10.17182/hepdata.20303

Hadronic production of charmed particles in association with muons from their semileptonic decay has been observed in a high-resolution streamer-chamber experiment performed at Fermilab. A miss-distance analysis of the pictures gives a signal of 17.3±4.7 events. Depending on the production model this corresponds to a range of neutron-nucleon cross sections from 8 to 50 μb, assuming an A23 dependence.

2 data tables

NEUTRON BEAM : 280 GEV - AVERAGE ENERGY, PEAKED AT 320 GEV WITH FWHW OF 130 GEV.

NEUTRON BEAM : 280 GEV - AVERAGE ENERGY, PEAKED AT 320 GEV WITH FWHW OF 130 GEV.


First Measurement of the Reaction $\pi^- e \to \pi^- \pi^0 e$

Amendolia, S.R. ; Arik, M. ; Badelek, B. ; et al.
Phys.Lett.B 155 (1985) 457-460, 1985.
Inspire Record 213172 DOI 10.17182/hepdata.30413

The first observation of neutral pion production in π e inelastic scattering is presented. The cross section at 300 GeV for | t ‖>62;10 −3 (GeV / c ) 2 is 2.11 ± 0.47 nb, in good agreement with the theory of PCAC anomalies with 3 quark colours.

1 data table

No description provided.