Hadron Production at SPEAR

Schwitters, R. ;
5, 1975.
Inspire Record 100733 DOI 10.17182/hepdata.70356
3 data tables

RADIATIVE TAILS OF PSI RESONANCES HAVE BEEN REMOVED. SIG(HAD) IS NOT TABULATED FOR 4.0 TO 4.4 GEV AS THE DATA POINTS ARE TOO CLOSE TO DISTINGUISH FROM THE GRAPH.

No description provided.

No description provided.


Azimuthal Asymmetry in Inclusive Hadron Production by e+ e- Annihilation

Schwitters, R. ; Boyarski, A. ; Breidenbach, Martin ; et al.
Phys.Rev.Lett. 35 (1975) 1320, 1975.
Inspire Record 100683 DOI 10.17182/hepdata.21192

We have observed an azimuthal asymmetry in inclusive hadron production by e+e− annihilation at the center-of-mass energy s=7.4 GeV. The asymmetry is caused by the polarization of the circulating beams in the storage ring and allows separate determination of the transverse and longitudinal structure functions. We find that transverse production dominates for x>0.2 where x is the scaling variable 2ps.

3 data tables

No description provided.

No description provided.

No description provided.


Total Cross-Section for Hadron Production by electron-Positron Annihilation Between 2.4-GeV and 5.0-GeV Center-Of-Mass Energy

Augustin, J.E. ; Boyarski, A. ; Breidenbach, Martin ; et al.
Phys.Rev.Lett. 34 (1975) 764, 1975.
Inspire Record 100592 DOI 10.17182/hepdata.21227

The total cross section for hadron production by e+e− annihilation has been measured at center-of-mass energies between 2.4 and 5.0 GeV. Aside from the very narrow resonances ψ(3105) and ψ(3695), the cross section varies between 32 and 17 nb over this region with structure in the vicinity of 4.1 GeV.

2 data tables

No description provided.

MEAN CHARGED MULTIPLICITY. ERRORS ARE STATISTICAL ONLY.


Production of 4 pi+- and 6 pi+- by e+ e- Annihilation Between 2.4-GeV and 7.4-GeV

Jean-Marie, B. ; Abrams, G.S. ; Boyarski, A. ; et al.
SLAC-PUB-1711, 1976.
Inspire Record 108089 DOI 10.17182/hepdata.18658

None

2 data tables

No description provided.

No description provided.


Hadron Production by $e^+ e^-$ Annihilation at Center-of-mass Energies Between 2.6-{GeV} and 7.8-{GeV}

Siegrist, James Leon ; Schwitters, Roy F. ;
SLAC-R-0225, 1979.
Inspire Record 143687 DOI 10.17182/hepdata.18825

Results are presented on multihadron production by e+e- annihilation from the Mark I and Mark II detectors at SPEAR. Other-than the narrow resonances psi(3095) and psi'(3634), the total hadronic cross section varies between 36.5 and 6.4 nb over the center-of-mass energy range 2.6 to 7.8 GeV with complicated structure near 4.1 GeV not completely resolved by these measurements. Evidence for scaling of inclusive momentum distributions of hadrons is presented.

3 data tables

No description provided.

MORE DETAILED TABULATION OF R IN THE TRANSITION REGION.

CHARGED SINGLE PARTICLE INCLUSIVE DISTRIBUTIONS FROM THIS EXPERIMENT ARE GIVEN IN THE RECORD OF G. G. HANSON, TBILISI CONFERENCE 1976, SLAC-PUB-1814.


K0 Production in e+ e- Annihilation

Luth, V. ; Pierre, F. ; Abrams, G.S. ; et al.
Phys.Lett.B 70 (1977) 120, 1977.
Inspire Record 119729 DOI 10.17182/hepdata.27537

The production of enutral kaons in e + e − annihilation has been measured for c.m. energies between 3.4 GeV and 7.6 GeV. Near 4 GeV the inclusive K S cross section shows an increase and structure similar to total hadron production. Roughly 40–45% of all hadronic final states contain kaons, except at 4.028 GeV and 4.415 GeV, where a significantly larger kaon fraction is observed.

2 data tables

No description provided.

THIS IS TWICE THE MEASURED KS CROSS SECTION. THE ERRORS ARE STATISTICAL ONLY. THERE IS 15 PCT ABSOLUTE NORMALIZATION ERROR, PLUS POSSIBLY SOME ENERGY DEPENDENT ERROR. THE DATA ARE NOT EQUALLY SPACED IN THE ENERGY INTERVALS.


Measurement of the Parameters of the $\psi^{\prime\prime}$(3770) Resonance

Abrams, G.S. ; Alam, M.S. ; Blocker, C.A. ; et al.
Phys.Rev.D 21 (1980) 2716, 1980.
Inspire Record 142644 DOI 10.17182/hepdata.24185

We present a measurement of the cross section for hadron production by e+e− annihilation in the vicinity of the previously observed resonance near 3.77 GeV. The data are used to determine the parameters of the ψ(3770) resonance. The values found are: mass, 3764±5 MeV/c2, total width, 23.5±5 MeV, and partial width to electron pairs, 276±50 eV.

3 data tables

THESE RESULTS ARE ALSO IN THE THESIS OF R. H. SCHINDLER, SLAC-219 (1979), THE RECORD OF WHICH CONTAINS THE TABULATED CROSS SECTIONS.

BREIT-WIGNER RESONANCE PLUS BACKGROUND FIT TO RADIATIVELY CORRECTED DATA YIELDS RESONANCE MASS OF 3764 +- 5 MEV, TOTAL WIDTH OF 23.5 +- 5 MEV AND PARTIAL WIDTH TO ELECTRON PAIRS OF 276 +- 50 EV.

PEAK CROSS SECTION FOR D MESON PAIR PRODUCTION AT PSI(3770) RESONANCE. J/PSI, PSI(3684) AND CONTINUUM BACKGROUND (R=2.5) SUBTRACTED.


Observation of Semileptonic Decays of Charmed Baryons

Vella, E. ; Trilling, G. ; Abrams, G.S. ; et al.
Phys.Rev.Lett. 48 (1982) 1515, 1982.
Inspire Record 176986 DOI 10.17182/hepdata.19674

Direct electrons are observed in baryon events produced in e+e− annihilation at center-of-mass energies above the ΛcΛ¯c threshold. These events are attributed to charmed-baryon pair production and subsequent Λc semileptonic decay. Various semileptonic branching ratios of the Λc are determined, including B(Λc→e+X)=(4.5±1.7)%.

2 data tables

ELECTRON-BARYON RATIO ABOVE AND BELOW LAMBDA/C THRESHOLD.

No description provided.


Observation of Charmed Baryon Production in e+ e- Annihilation

Abrams, G.S. ; Alam, M.S. ; Blocker, C.A. ; et al.
Phys.Rev.Lett. 44 (1980) 10, 1980.
Inspire Record 142743 DOI 10.17182/hepdata.20754

A peak in the pK−π+ and p¯K+π− invariant-mass spectra at 2.285±0.006 GeV/c2 is observed, which is associated with the lowest-lying charmed baryon (Λc). A cross section times branching ratio of 0.037±0.012 nb at Ec.m.=5.2 GeV is measured with a substantial fraction of the events produced with an equal recoiling mass. New measurements of inclusive p and Λ cross sections are also presented, allowing an estimate of the branching ratio B(Λc→pK−π+)=0.022±0.010.

3 data tables

THE TOTAL INCLUSIVE CHARMED LAMBDA CROSS SECTION IS DERIVED FROM THE OBSERVED PRODUCTION RATE VIA THE <P K- PI+> CHANNEL USING THE STEP IN INCLUSIVE PROTON PRODUCTION AT THE CHARMED-BARYON THRESHOLD AND REASONABLE ASSUMPTIONS. THE BRANCHING RATIO (LAMBDA/C+ --> P K- PI+) IS THEN 2.2 +- 1.0 PCT.

ACTUALLY TWICE THE INCLUSIVE ANTI-PROTON CROSS SECTION (EACH BARYON PAIR IS COUNTED TWICE).

EACH BARYON PAIR PRODUCED IS OF COURSE COUNTED TWICE IN THIS CROSS SECTION.


Measurement of $s d \sigma$ / Dx for Hadron Production by $e^+ e^-$ Annihilation at $\sqrt{s}=5$.2-{GeV}, 6.5-{GeV} and 29.0-{GeV}

Patrick, J.F. ; Luth, V. ; Siegrist, J. ; et al.
Phys.Rev.Lett. 49 (1982) 1232, 1982.
Inspire Record 178416 DOI 10.17182/hepdata.20599

Measurements are presented of the inclusive charged-particle cross sections s dσdx for e+e− annihilation at center-of-mass energies of 5.2, 6.5, and 29.0 GeV. Significant scale breaking is observed in these cross sections.

1 data table

CROSS SECTION S*D(SIG)/DX FOR CHARGED PARTICLES AT SQRT(S) = 5.2, 6.5 AND 29.0 GEV. NUMERICAL VALUES OF DATA TAKEN FROM THESIS OF J.F. PATRICK LBL-14585.