Arends, H.J.
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Study of the $\rho^\prime$ (1600) Mass Region Using $\gamma p \to \pi^+ \pi^- p$ at 20-{GeV}

The SLAC Hybrid Facility Photon collaboration Abe, K. ; Bacon, T.C. ; Ballam, Joseph ; et al.
Phys.Rev.Lett. 53 (1984) 751, 1984.
Inspire Record 201710 DOI 10.17182/hepdata.20387

We have observed the π+π− decay of the ρ′(1600) in the production reaction γp→ρ′p at 20 GeV. Using a calculation which takes into account the interference of the ρ′ with the ρ(770) and a Drell background, we find good evidence that this resonance is a radial excitation of the ρ(770). The background interference strongly distorts the angular distributions predicted by a purely s-channel helicity-conserving production mechanism. We measure m0=(1.55±0.07) GeV/c2 and Γ0=(0.28−0.08+0.03) GeV/c2.

4 data tables
Table 1

SLOPE VARIATION WITH M(PI+ PI-) IN THE RANGE 0.4 TO 2.5 GEV.

Table 2

No description provided.

Table 3

No description provided.

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rivet Analysis
Search for New Heavy Quarks in $e^+ e^-$ Collisions Up to 46.78-{GeV} Center-of-mass Energy

The CELLO collaboration Behrend, H.J. ; Burger, J. ; Criegee, L. ; et al.
Phys.Lett.B 144 (1984) 297-301, 1984.
Inspire Record 202783 DOI 10.17182/hepdata.30514

The total e + e − annihilation onto hadron has been measured at CM energies between 33.00 and 36.72 GeV and between 38.66 and 46.78 GeV in steps of 20 and 30 MeV respectively. The average of the ratio R = σ ( e + e − → hadrons )/ σ is 〈 R 〉=3.85±0.12 and 〈 R 〉=4.04±0.10 for the two energy ranges. The systematic error on 〈 R 〉 is 0.31. Both values are consistent with the expectation for the known coloured quarks u, d, s, c and b. No evidence was found for the production of new quarks. If the largest fluctuation in R is interpreted as a narrow resonance, it corresponds to a product of the electronic width and the hadronic branching ratio Γ ee B had >2.9 keV at the 95% confidence level, well below the value expected for the toponium vector ground state with charge 2 3 e . The observed number of aplanar final states rules out the continuum production of a a new heavy flavour with pointlike cross section up to a CM energy of 45.4 GeV for a quarck charge of 1 3 e . and up to 46.6 GeV for 2 3 e at the 95% confidence level.

2 data tables
Table 1

ENERGY SCANS IN 20(30) MEV STEPS.

Table 2

No description provided.


MEASUREMENT OF THE REACTION gamma p ---> p anti-p p AT PHOTON ENERGIES 4.7-GeV <= E (gamma) <= 6.6-GeV

Bodenkamp, J. ; Fries, D.C. ; Markou, A. ; et al.
Nucl.Phys.B 255 (1985) 717-746, 1985.
Inspire Record 15090 DOI 10.17182/hepdata.33786

An experimental investigation of the reaction γ p → p p p at photon energies 4.7 ⩽ E γ ⩽ 6.6 GeV is described. The main results are the measurement of the cross section as a function of energy, a discussion of the main dynamical features of the reaction and the observation of a narrow p p mass state at 2.024 ± 0.005 GeV with a width of 29 ± 13 MeV.

3 data tables
Table 1

OBSERVATION OF THIS CHANNEL AS A CONSISTENCY CHECK ON THE NORMALIZATION.

Table 2

No description provided.

Table 3

MEASUREMENTS OF CROSS SECTIONS OF MASS SIGNALS AT 1.94 AND 2.024 GEV, EVALUATE BY FITTING TWO BREIT WIGNERS AND CONSTANT BACKGROUND TO (AP P) MASS SPECTRUM. ERRORS ARE STATISTICAL ONLY.


Measurement of the Photon Structure Function F2 (x, Q**2)

The PLUTO collaboration Berger, Christoph ; Deuter, A. ; Genzel, H. ; et al.
Phys.Lett.B 142 (1984) 111-118, 1984.
Inspire Record 201376 DOI 10.17182/hepdata.30545

None

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Measurement of Exclusive $\eta^\prime$ Production in $\gamma \gamma$ Reactions

The PLUTO collaboration Berger, Christoph ; Deuter, A. ; Genzel, H. ; et al.
Phys.Lett.B 142 (1984) 125-129, 1984.
Inspire Record 201708 DOI 10.17182/hepdata.30533

We observe γγ → η′ production in the reaction e + e − → e + e − π + π − γ. We measure the product γ γγ ( η ′) B ( η ′ → ϱ 0 γ ) to be 1.14 ± 0.08 ± 0.11 keV. A first measurement of the γγ → η′ transition form factor is made for Q 2 up to 1 GeV 2 .

1 data table
Table 1

No description provided.


Search for a Threshold Enhancement in the $\gamma (p) \to$ Charmed Baryon + Charmed Meson Cross-section

The SLAC Hybrid Facility Photon collaboration Abe, K. ; Bacon, T.C. ; Bingham, H.H. ; et al.
Phys.Rev.D 30 (1984) 694, 1984.
Inspire Record 200010 DOI 10.17182/hepdata.23592

Results of a search for a predicted enhancement of several microbarns in the charm-photoproduction cross section just above threshold are reported. No charm decays were detected, from which an upper limit to the charm cross section of 94 nb (90% C.L.) at Eγ≃10 GeV was obtained. Upper limits in the range 270 to 450 nb were also obtained for the peak cross sections for threshold enhancements in γp→D−Σc++ and similar channels.

2 data tables
Table 1

UPPER LIMIT TO AVERAGE CHARM CROSS SECTION.

Table 2

UPPER LIMITS TO INDIVIDUAL CHANNELS.


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
Table 1

No description provided.


Jets in High Transverse Energy Events at the {CERN} Intersecting Storage Rings

The CMOR collaboration Angelis, A.L.S. ; Basini, G. ; Besch, H.J. ; et al.
Nucl.Phys.B 244 (1984) 1-22, 1984.
Inspire Record 202452 DOI 10.17182/hepdata.33870

Most events with high neutral transverse energy, E T 0 , produced in pp colisions at √ s = 62.3 GeV, are jet-like. The evidence for this is presented, based on data collected using an electromagnetic calorimeter covering 90% of 2π in azimuth. The spectrum d N /d E T 0 has been measured over the E T 0 range from 10 to 35 GeV. Properties of the observed jets are discussed.

1 data table
Table 1

No description provided.


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
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


MEASUREMENT OF COHERENT pi0 PHOTOPRODUCTION ON HE-3 AND H-3 IN THE RESONANCE REGION

Bellinghausen, B. ; Gassen, H.J. ; Reese, E. ; et al.
Z.Phys.A 318 (1984) 83, 1984.
Inspire Record 200794 DOI 10.17182/hepdata.50169

Neutral pion photoproduction has been measured on3He and3H nuclei in theΔ(1232) resonance region. Resonance averaged cross-sections are presented as a function of momentum transfer and compared to theoretical calculations.

1 data table
Table 1

No description provided.