Armbruster, P.
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Inclusive production of eta mesons in pi p, K p and gamma p collisions at energies around 100-GeV.

The Omega Photon collaboration Apsimon, R.J. ; Atkinson, M. ; Baake, M. ; et al.
Z.Phys.C 54 (1992) 185-191, 1992.
Inspire Record 339919 DOI 10.17182/hepdata.14710

Measurements are reported of inclusive production of η-mesons in the beam fragmentation region in γp, πp andKp collisions. Results include a small but significant departure from VMD, and a pronounced rise in theη/π0 ratio with increasingpT.

21 data tables
Table 1

No description provided.

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Measurement of the C-12 (p, pi0) N-13 reaction by recoil detection

Homolka, J. ; Schott, W. ; Wagner, W. ; et al.
Phys.Rev.C 45 (1992) 1276-1283, 1992.
Inspire Record 338519 DOI 10.17182/hepdata.26048

Differential cross sections for the neutral pion production reaction C12(p,π0)13Ng.s. have been measured at 153.5, 166.1, 186.0, and 204.0 MeV bombarding energy using recoil detection. The shape of the angular distribution agrees well with that of the mirror reaction C12(p,π+)13Cg.s.. Isospin invariance predicts for the ratio of the cross sections σ(p,π+)/σ(p,π0)=2. At 153.5, 166.1, and 186.0, MeV, where (p,π+) cross sections have been reported previously by other groups at the same reduced pion momentum η=pπ/mπc=0.34,0.55,0.78, the ratio of the total cross sections is 2.02±0.14, 3.14±0.12, and 2.12±0.16, respectively. The (p,π0) cross sections at 166 MeV is therefore 1.57±0.06 times larger than expected. For Tp<160 MeV, the experimental cross sections are larger than predicted by a phase space and Coulomb barrier penetration calculation that fits the higher-energy data. Differential cross sections were also obtained for the C12(p,π−)13O reaction, and upper limits set for differential cross sections for radiative capture to the ground state of N13.

1 data table
Table 1

No description provided.


Measurement of the slope of the pi0 electromagnetic form-factor

Farzanpay, F. ; Gumplinger, P. ; Stetz, A. ; et al.
Phys.Lett.B 278 (1992) 413-418, 1992.
Inspire Record 338523 DOI 10.17182/hepdata.29240

We have measured the slope parameter of the π 0 electromagnetic form factor by measuring the partial branching ratio of the Dalitz decay π 0 → γe + e − into high-invariant-mass electron-positron pairs. We obtain a value a =0.026 with a total (statistical and systematic) error of ±0.054, in agreement with vector dominance and quark loop calculations.

1 data table
Table 1

The PI0 form factor is parameterized as F(M(ee)**2) = 1 + SLOPE*(M(ee)/M(pi))**2. Two metod are used (see text for detail).


n p elastic spin transfer measurements at 485-MeV and 635-MeV

McNaughton, K.H. ; Ambrose, D.A. ; Coffey, P. ; et al.
Phys.Rev.C 46 (1992) 47-51, 1992.
Inspire Record 342389 DOI 10.17182/hepdata.26097

We have measured the spin-transfer parameters KLL, KSL, KLS, and KSS at 635 MeV from 50° to 178° c.m. and at 485 MeV from 74° to 176° c.m. These new data have a significant impact on the phase-shift analyses. There are now sufficient data near these energies to overdetermine the elastic nucleon-nucleon amplitudes.

2 data tables
Table 1

Spin transfer parameters from np elastic scattering at 635 MeV. There is an additional overall normalisation of 2 PCT.

Table 2

Spin transfer parameters from np elastic scattering at 485 MeV. There is an additional overall normalisation of 2 PCT.


A Measurement of the K+ K- / pi+ pi- ratio from anti-p annihilation in deuterium and hydrogen gas

Adamo, A. ; Agnello, M. ; Balestra, F. ; et al.
Phys.Lett.B 284 (1992) 448-452, 1992.
Inspire Record 339776 DOI 10.17182/hepdata.29172

We have measured the K + K - /π + π - ratio R from p annihilations in gaseous D 2 and H 2 at atmospheric pressure. The measurement was performed with the OBELIX spectrometer. From the measured value in gaseous D 2 (0.27±0.02) we infer a P wave contribution to p −p annihilation in D 2 of (18±7)%.

1 data table
Table 1

Two different triggers were used.


Recent results from experiment NA35.

The NA35 collaboration Seyboth, P. ; Baechler, J. ; Bartke, J. ; et al.
Nucl.Phys.A 544 (1992) 293C-307C, 1992.
Inspire Record 343637 DOI 10.17182/hepdata.36668

Enhanced strange particle production, nonstatistical multiplicity fluctuations and two-pion Bose-Einstein correlations were measured in O, S-nucleus reactions at 60 and 200 GeV/nucleon. The results indicate significant collective effects in high-energy nucleus-nucleus collisions.

2 data tables
Table 1

CENTRAL COLLISIONS.

Table 2

CENTRAL COLLISIONS.


Production of charged kaons in central S + S and O + Au collisions at 200-GeV/nucleon

The NA35 collaboration Kowalski, M. ; Bachler, J. ; Bartke, J. ; et al.
Nucl.Phys.A 544 (1992) 609C-614C, 1992.
Inspire Record 343256 DOI 10.17182/hepdata.36667

Product of charged kaons in central S + S and O + Au collisions at 200 GeV/nucleon has been studied in the NA 35 Streamer Chamber experiment. Mean multiplicities and transverse mass distributions were obtained. They were compared with nucleon-nucleon data and with model predictions.

5 data tables
Table 1

No description provided.

Table 2

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Measurements at 0-degrees of negatively charged particles and anti-nuclei produced in collision of 14.6-A/GeV/c Si on Al, Cu, and Au targets

Aoki, M. ; Beatty, J. ; Beavis, D. ; et al.
Phys.Rev.Lett. 69 (1992) 2345-2348, 1992.
Inspire Record 344921 DOI 10.17182/hepdata.19827

We report measurements of d¯, p¯, K−, and π− produced at 0° in collisions of 14.6A GeV/c Si28 on Al, Cu, and Au targets. A beam-line focusing spectrometer was used to identify particles at rigidities from -2 to -8 GV. The ratio of d¯/p¯ invariant cross sections at midrapidity (y=1.7) is (1±0.7)×10−5, larger than expected from a calculation of dd¯ direct production but smaller than predicted by a simple coalescence model. We also report limits on the production of exotic particles.

10 data tables
Table 1

No description provided.

Table 2

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Table 3

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Measurement of B0 anti-B0 mixing at the Fermilab Tevatron collider

The CDF collaboration Abe, F. ; Amidei, Dante E. ; Apollinari, G. ; et al.
Phys.Rev.Lett. 67 (1991) 3351-3355, 1991.
Inspire Record 332810 DOI 10.17182/hepdata.19881

The B0 B¯ 0 average mixing parameter χ has been extracted from eμ and ee events produced in pp¯ collisions at √s =1.8 TeV. In a sample of 900 eμ events, the like-sign to opposite-sign charge ratio R is measured to be 0.556±0.048(stat)−0.042+0.035(syst). In the absence of mixing, the expected value of R would be 0.23±0.06. The corresponding number for 212 ee events is 0.573±0.116(stat)±0.047(syst) with an expected nonmixing value of 0.24±0.07. The observed excess in R leads to a combined determination of χ=0.176±0.031(stat+syst) ±0.032 (model), where the last uncertainty is due to Monte Carlo modeling.

2 data tables
Table 1

No description provided.

Table 2

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Prompt fission induced by anti-proton annihilation at rest on heavy nuclei

Bocquet, J.P. ; Malek, Fairouz ; Nifenecker, H. ; et al.
Z.Phys.A 342 (1992) 183-189, 1992.
Inspire Record 343226 DOI 10.17182/hepdata.16577

Antiproton induced fission probabilities of U238, Bi209, Pb208 and Au177 are reported together with the mass distribution of the fission fragments in the U238 and Bi209 cases. The charged particles multiplicities observed in co-incidence with fission have, also, been measured for U and Bi and are presented.

1 data table
Table 1

TOTAL AVERAGE MASSES AND KINETIC ENERGIES OF FISSION FRAGMENTS. Mean mass is in proton mass units.