Iovchev, K.
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Observation of a Peak at 1.28-{GeV} in the $\eta \pi \pi$ System in the Reaction $\gamma p \to \eta \pi^+ \pi^- p$

The Omega Photon collaboration Atkinson, M. ; Axon, T.J. ; Barberis, D. ; et al.
Nucl.Phys.B 242 (1984) 269-281, 1984.
Inspire Record 194474 DOI 10.17182/hepdata.33873

A peak is reported in the ηπ + π − system, produced in the reaction γ p→ ηπ + π − p, at a mass of 1.28 ± 0.01 GeV with a width of 0.08 ± 0.02 GeV. Possible spin-parity assignments for the peak are shown to be J π = 1 − , J π = 1 + or J π = 2 + and interpretations of these assignments are discussed.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Inclusive $\pi^0$ Production in 360-{GeV} $p p$ Interactions Using the European Hybrid Spectrometer

The EHS-RCBC collaboration Bailly, J.L. ; Bartl, W. ; Bruyant, F. ; et al.
Z.Phys.C 22 (1984) 119, 1984.
Inspire Record 193697 DOI 10.17182/hepdata.2106

The intermediate and forward gamma detectors of EHS are used to reconstructπ°'s produced by 360 GeV/cpp interactions in the Rapid Cycling Bubble Chamber (RCBC). Using thepp forwardbackward symmetry, the inclusiveπ° production cross section is obtainedσπ°=(132±11) mb. The averageπ° multiplicity is determined as a function of the charged particle multiplicity. The (1−x) dependence is given for differentpT regions.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

Axis error includes +- 4/4 contribution.


Inelastic and Elastic Photoproduction of J/$\psi$ (3097)

Denby, Bruce H. ; Bharadwaj, V.K. ; Summers, D.J. ; et al.
Phys.Rev.Lett. 52 (1984) 795-798, 1984.
Inspire Record 195929 DOI 10.17182/hepdata.20438

Inelastic and elastic $J/\psi$ photoproduction on hydrogen are investigated at a mean energy of 105 GeV. The inelastic cross section with $E_{\psi} / E_{\gamma}$ < 0.9 is significantly lower than the corresponding result for muoproduction on iron targets, but is consistent with a second-order perturbative QCD calculation.

1 data table
Table 1

No description provided.


CHARM PHOTOPRODUCTION AT 20-GeV

The SLAC Hybrid Facility Photon collaboration Abe, K. ; Bacon, T.C. ; Ballam, Joseph ; et al.
Phys.Rev.D 30 (1984) 1, 1984.
Inspire Record 194546 DOI 10.17182/hepdata.23639

Sixty-two charm events have been observed in an exposure of the SLAC Hybrid Facility toa backward sacttered laser beam. Based on 22 neutral and 21 charged decays we have measured the charmed-meson lifetimes to be τD0=(6.8−1.8+2.3)×10−13 sec, τD±=(7.4−2.0+2.3)×10−13 sec and their ratio τD±τD0=1.1−0.3+0.6. The inclusive charm cross section at a photon energy of 20 GeV has been measured to be 56−23+24 nb. Evidence is presented for a non-DD¯ component to charm production, consistent with (35±20)% Λc+ production and some D*± production. We have found no unambiguous F decays.

1 data table
Table 1

No description provided.


The $\Lambda(c$)+ Baryon Production in Interactions of 40-{GeV} to 70-{GeV} Neutrons With Carbon Nuclei

The Dubna-Berlin-Budapest-Moscow-Prague-Sofiya-Tbilisi collaboration Aleev, A.N. ; Arefev, V.A. ; Balandin, V.P. ; et al.
Z.Phys.C 23 (1984) 333, 1984.
Inspire Record 196745 DOI 10.17182/hepdata.16228

The inclusive production of charmed baryonsΛc+ by 40–70 GeV neutrons on carbon has been observed. The decays\(\Lambda _c^ + \to \bar K^0 p\pi ^ + \pi ^ -\) (130 ± 18 events) andΛc+→Λ0π+π+π− (57±14 events) have been detected. The mean value ofΛc+ mass is (2,268±6) MeV/c2. The invariant cross section forX>0.5 is described byE·d3σ/dp3∝ exp(−)bPT·(1−X)n withb=(2.5±0.6) (GeV/c)−1 andn=(1.5±0.5).

2 data tables

Angular Distributions and Structure Functions from Two Jet Events at the CERN SPS $p \bar{p}$ Collider

The UA1 collaboration Arnison, G. ; Astbury, A. ; Aubert, Bernard ; et al.
Phys.Lett.B 136 (1984) 294-300, 1984.
Inspire Record 195946 DOI 10.17182/hepdata.30581

The two-jet cross section measured in the UA1 apparatus at the CERN p p Collider has been analysed in terms of the centre-of-mass scattering angle θ and the scaled longitudinal parton momenta x 1 and x 2 . The angular distribution d σ /d cos σ rises rapidly as cos → 1, independent of x 2 and x 2 , as expected in vector gluon theories (QCD). The differential cross section in x 1 and x 2 is consistent with factorization and provides a measurement of the proton structure function F(x) = G(x) + 4 9 [Q(x) + Q (x)] at values of the four-momentum transfer squared, -t̂ ≈ 2000 GeV 2 . Over the range x = 0.10−0.80 the structure function shows an exponential x dependence and may be parametrized by the form F ( x ) = 6.2 exp (−9.5 x ).

2 data tables
Table 1

S(X1,X2) IS DEFINED BY X1*X2*D2(SIG)/DX1/DX2 NORMAISED APPROPRIATELY.

Table 2

F(X) DEFINED AS G(X)+(4/9)*(Q(X)+QBAR(X)).


Observation of the Muonic Decay of the Charged Intermediate Vector Boson

The UA1 collaboration Arnison, G. ; Astbury, A. ; Aubert, Bernard ; et al.
Phys.Lett.B 134 (1984) 469-476, 1984.
Inspire Record 195217 DOI 10.17182/hepdata.30609

Muons of high transverse momentum p μ T have been observed in the large drift chambers surrounding the UA1 detector at the CERN 540 GeV pp̄ collider. For an integrated luminosity of 108 nb −1 , 14 isolated muons have been found with p T > 15 GeV/ c . They are correlated with a large imbalance in total transverse energy, and show a kinematic behaviour consistent with the muonic decay of the Intermediate Vector Boson W ± of weak interactions. The partial cross section is in agreement with previous measurements for electronic decays and with muon-electron universality. The W mass is determined to be m W = 81 +6 −7 GeV/ c 2 .

1 data table
Table 1

No description provided.


A Spin Parity Analysis of the $\omega \pi^0$ Enhancement Photoproduced in the Energy Range 20-{GeV} to 70-{GeV}

The Omega Photon collaboration Atkinson, M. ; Axon, T.J. ; Barberis, D. ; et al.
Nucl.Phys.B 243 (1984) 1-28, 1984.
Inspire Record 195216 DOI 10.17182/hepdata.33872

A study is made of the ωπ 0 system produced near threshold in the reaction γ p→ π + π − π 0 π 0 p. A spin-parity analysis shows that the ωπ 0 enhancement is consistent with predominant 1 + B(1235) production, with ∼20% J P = 1 − background.

2 data tables
Table 1

MEAN BEAM ENERGY IS 39 GEV.

Table 2

ESTIMATE OF B(1235) PRODUCTION CROSS SECTION ASSUMING 1+ CROSS SECTION OF 0.63 +- 0.20 MUB AND THAT 20 PCT OF THIS IS DUE TO BACKGROUND S-WAVE CONTRIBUTIONS.


rivet Analysis
A Summary of Recent Experimental Results From Mark-$J$: High-energy $e^+ e^-$ Collisions at {PETRA}

The Mark-J collaboration Adeva, B. ; Barber, D.P. ; Becker, U. ; et al.
Phys.Rept. 109 (1984) 131, 1984.
Inspire Record 196567 DOI 10.17182/hepdata.30997

None

6 data tables
Table 1

DATA ARE CORRECTED FOR TWO-PHOTON AND TAU PRODUCTION EFFECTS, ACCEPTANCE AND QED RADIATIVE EFFECTS UP TO ORDER ALPHA**3. THERE IS ALSO A 6 PCT NORMALISATION ERROR NOT INCLUDED. THE OVERALL AVERAGE VALUE OF R FROM THIS DATA IS 3.88 +- 0.04 +- 0.22.

Table 2

No description provided.

Table 3

SEE PRL 55, 665 FOR MOST RECENT VALUES OF THE MU+ MU- CROSS SECTIONS.

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On the Model Dependence of the Determination of the Strong Coupling Constant in Second Order {QCD} From $e^+ e^-$ Annihilation Into Hadrons

The CELLO collaboration Behrend, H.J. ; Fenner, H. ; Schachter, M.J. ; et al.
Phys.Lett.B 138 (1984) 311-316, 1984.
Inspire Record 195332 DOI 10.17182/hepdata.6634

Hadronic events obtained with the CELLO detector at PETRA are compared with second order QCD predictions using different models for the fragmentation of quarks and gluons into hadrons. We find that the model dependence in the determination of the strong coupling constant persists when going from first to second order QCD calculations.

3 data tables
Table 1

ASYMMETRY FOR DATA CORRECTED WITH IF MODEL (ALPHA-S=0.12).

Table 2

ASSYMETRY FOR DATA CORRECTED WITH SF MODEL (ALPHA-S=0.19).

Table 3

No description provided.