Date

Observation of Octet and Decuplet Hyperons in $e^+ e^-$ Annihilation at 10-{GeV} Center-of-mass Energy

The ARGUS collaboration Albrecht, H. ; Binder, U. ; Bockmann, P. ; et al.
Phys.Lett.B 183 (1987) 419-424, 1987.
Inspire Record 236982 DOI 10.17182/hepdata.30227

Results on hyperon production are reported for data accumulated at 10 GeV centre-of-mass energy with the ARGUS detector. Signals for both the octet states Λ, Σ 0 and Ξ − and the decuplet states Σ ± (1385), Ξ 0 (1530) and Ω − are observed 1 (references to a specific state are to be interpreted as also implying the charge conjugate state), some for the first time in e + e − annihilation. Baryon rates from γ dir (1S) decays are enhanced by a factor of about 3 over the continuum.

2 data tables

No description provided.

No description provided.


Inclusive $\pi^0$ Production by $e^+ e^-$ Annihilation at 34.6-{GeV} Center-of-mass Energy

The TASSO collaboration Braunschweig, W. ; Gerhards, R. ; Kirschfink, F.J. ; et al.
Z.Phys.C 33 (1986) 13, 1986.
Inspire Record 230950 DOI 10.17182/hepdata.45205

The cross section for the processe+e−→π0+ anything has been measured at an average center of mass energy of 34.6 GeV for π0 energies between 0.7 and 17 GeV. The angular distribution for π0 energies larger than 2 GeV is of the formdσ/dΩ∼1+Acos2θ, withA=1.2±0.5. The ratio of π0 to π± production in the measured energy range is 2σ(π0)/(σ(π+)+σ(π−))=1.13±0.18

6 data tables

Systematic errors included.

Systematic errors included.

No description provided.

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A Measurement of the Sigma- Magnetic Moment Using the Sigma- ---> n e- anti-neutrino and Sigma- ---> n pi- Decay Modes

Zapalac, G. ; Hsueh, S.Y. ; Muller, D. ; et al.
Phys.Rev.Lett. 57 (1986) 1526, 1986.
Inspire Record 231107 DOI 10.17182/hepdata.42694

We have used the spin-precession technique to measure the Σ− magnetic moment (μΣ). A Σ− beam with a polarization of 22% was produced by a 400-GeV proton beam striking a Cu target at nominal production angles of ±3 mrad. We simultaneously recorded 21 000 Σ−→ne−ν¯ decays and 650 000 Σ−→nπ− decays at Σ− beam momenta of 253 and 308 GeV/c. We find μΣ=−1.166±0.014±0.010 nuclear magnetons, where the quoted errors are statistical and systematic, respectively.

1 data table

No description provided.


Measurement of the Radiative Width of the A(2) (1320) in Two Photon Interactions

The TASSO collaboration Althoff, M. ; Braunschweig, W. ; Gerhards, R. ; et al.
Z.Phys.C 31 (1986) 537, 1986.
Inspire Record 228876 DOI 10.17182/hepdata.15859

The reactione+e−→e+e− A2 (1320) has been observed by detecting the decayA2→π+,π-π0. The two-photon width of theA2 has been measured to be Г(A2→γγ)=(0.09±0.27 (stat)±0.16 (syst)) keV. The cross section σ(γγ→π+,π-π0 has been determined outside theA2 resonance region.

1 data table

Data read off a graph.


Inclusive Hadronic Production Cross-Sections Measured in Proton - Nucleus Collisions at s**(1/2) = 27.4-GeV

Crittenden, J.A. ; Hsiung, Y.B. ; Kaplan, D.M. ; et al.
Phys.Rev.D 34 (1986) 2584, 1986.
Inspire Record 231109 DOI 10.17182/hepdata.23462

We present results on the production of hadrons in collisions of 400-GeV/c protons with beryllium, copper, and tungsten nuclei. The data cover the region from 5.6 to 8.0 GeV/c in the transverse momentum of the final-state hadron and from 73° to 102° in the proton-nucleon center-of-momentum frame production angle theta*. The restriction of the data to values of xT (xT=2pT/ √s ) greater than 0.4 enriches the sample with hard collisions of valence quarks. Asymmetries about theta*=90° reflect the presence of neutrons in the target nuclei. The variation of the atomic-weight dependence parameter α with production angle is discussed in the context of the phenomenology of nucleonic structure within nuclei. We also extrapolate our measurements to a ‘‘deuteron’’ target to minimize nuclear effects and compare the result to QCD calculations.

2 data tables

No description provided.

No description provided.


Measurement of the Photon Structure Function f(2)Gamma at Q**2 from 7-GeV/c**2 to 70-GeV/c**2

The TASSO collaboration Althoff, M. ; Braunschweig, W. ; Gerhards, R. ; et al.
Z.Phys.C 31 (1986) 527, 1986.
Inspire Record 228251 DOI 10.17182/hepdata.15858

We have measured the processe+e−→e+e−+hadrons, where one of the scattered electrons was detected at large angles, withQ2 ranging from 7 to 70 (VeV/c)2. The photon structure functionF2γ(x, Q2) was determined at an averageQ2 of 23 (GeV/c)2. The measurements were compared to theoretical predictions of the Quark Parton Model and Quantum Chromodynamics. In both models a hadronic part was added. Within the errors the data are in agreement with the QPM using quark masses of 300 MeV/c2 for the light quarks. The data also agree with a QCD calculation including higher order corrections. A fit yielded a\(\Lambda _{\overline {MS} } \) value of 140−65+190 MeV, where the errors include statistical and systematic uncertainties.

1 data table

No description provided.


Vector Meson Production in the Final State $K^+ K^- \pi^+ \pi^-$ Photon-photon Collisions

The TASSO collaboration Althoff, M. ; Braunschweig, W. ; Gerhards, R. ; et al.
Z.Phys.C 32 (1986) 11, 1986.
Inspire Record 228250 DOI 10.17182/hepdata.15846

Vector meson production is studied in the reaction γγ→K+K−π+π−. A clear Φ(1020) signal is seen in theK+K− mass distribution and aK*0 (890) signal is visible in theK±π∓ one. Both do not seem to be strongly correlated with quasi two body final states. Cross sections for the processes γγ→K+K−π+π−, γγ→Φπ+π−, γγ→K+0K±π∓ and upper limits for the production of Φp, ΦΦ andK*0\(\overline {K^{ * 0} } \) are given as function of the invariant γγ mass.

5 data tables

No description provided.

First data point is sum of (K* K PI) and (K* AK*).

Non resonant phase space.

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High-energy Photoproduction of Large Transverse Momentum $\pi^0$ Mesons: A Quantitative Test of {QCD}

The NA14 collaboration Auge, E. ; Barate, R. ; Bloch, D. ; et al.
Phys.Lett.B 168 (1986) 163-169, 1986.
Inspire Record 227057 DOI 10.17182/hepdata.30278

The first results on inclusive photoproduction of π 0 at transverse momenta up to 4 GeV/ c , using incident γ energies between 50 and 150 GeV are presented. A comparison is made with inclusive π 0 production obtained, in the same experiment, with incident π − . Using the π − data to parametrize the hadronic behaviour of the photon, significant differences are observed in quantitative agreement with QCD Compton scattering and corrections thereof.

2 data tables

FC,IC,BC REFER TO FORWARD,INTERMEDIATE AND BACKWARD CALORIMETERS.

FC,IC,BC REFER TO FORWARD,INTERMEDIATE AND BACKWARD CALORIMETERS.


INCLUSIVE SPECTRA OF He, Li, Be, B FRAGMENTS PRODUCED ON NUCLEI BY ELECTRONS WITH ENERGIES OF 2-GeV AND 4.5-GeV AT ANGLE 0

Aivazian, G.M. ; Arutunian, V.N. ; Akhverdian, E.A. ; et al.
EFI-859-10-86-YEREVAN, 1985.
Inspire Record 223426 DOI 10.17182/hepdata.18428

None

2 data tables

FIT IN THE RANGE OF KINETIC ENERGY OF FRAGMENTS FROM 4 TO 8 MEV/NUCLEON.

FIT IN THE RANGE OF KINETIC ENERGY OF FRAGMENTS FROM 4 TO 8 MEV/NUCLEON.


Observation of a New Charmed Meson.

The ARGUS collaboration Albrecht, H. ; Binder, U. ; Harder, G. ; et al.
Phys.Rev.Lett. 56 (1986) 549, 1986.
Inspire Record 222219 DOI 10.17182/hepdata.20225

Using the ARGUS detector at the DORIS II e+e− storage ring at DESY, we have obtained evidence for a new charmed resonance which decays into D*±(2010)π∓. The observed mass and width are 2420±6 MeV/c2 and 70±21 MeV/c2, respectively. The fragmentation function is found to be hard, as expected for a state containing a leading charm quark produced by nonresonant e+e− annihilation.

2 data tables

No description provided.

Estimated production cross section obtained by comparison with observed D*(2010) production rate.