Photoproduction of Neutral Pions from Hydrogen in the Energy Range 700-1100 Mev

Bingham, H.H. ; Clegg, A.B. ;
Phys.Rev. 112 (1958) 2053-2061, 1958.
Inspire Record 944994 DOI 10.17182/hepdata.735

Gamma-rays from the decay of neutral pions photoproduced from hydrogen by the bremsstrahlung beam of the Caltech synchrotron have been studied with a thallium chloride crystal total absorption spectrometer. The energy spectrum of the decay gamma-rays produced by a range of incident photon energy is obtained by the photon difference method and this spectrum enables a separation of the gamma-rays into two groups: (i) those from the decay of neutral pions produced singly from hydrogen and (ii) those from the decay of neutral pions from multipleproduction reactions. The cross sections for the single-production reaction are in agreement with the recoil proton experiments at Caltech and Cornell. For the multiple-production reactions we measure the cross section for producing neutral pions within a range of kinetic energies: It is shown that all available multiple-production data can be explained in terms of two compound states, one at about 750 Mev and the other at some higher energy. This is in agreement with an analysis of the single-photoproduction data, which is given in an appendix. These two states are, respectively, (T=12, J=12+) and (T=32, J=12+).

4 data tables

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Investigation of two-prong pi+ p interactions at 2.34 gev/c.

Angelov, N. ; Gramenitsky, I.M. ; Kanazirsky, H. ; et al.
Yad.Fiz. 11 (1970) 613-628, 1970.
Inspire Record 63401 DOI 10.17182/hepdata.19286

None

1 data table

No description provided.


Pi- p interactions at 3.25 gev/c. two-prong events

Guzhavin, V.M. ; Vetlitskii, I.A. ; Kaidalov, A.B. ; et al.
Yad.Fiz. 14 (1971) 354-366, 1971.
Inspire Record 69448 DOI 10.17182/hepdata.19292

None

1 data table

BREIT-WIGNER RESONANCE FITS WITH BACKGROUND.


Average charged particle multiplicity and topological cross-sections in 50-GeV/c and 69-GeV/c p p interactions

Ammosov, V.V. ; Boitsov, V.N. ; Ermolov, P.F. ; et al.
Phys.Lett.B 42 (1972) 519-521, 1972.
Inspire Record 74383 DOI 10.17182/hepdata.28174

In an exposure of the chamber Mirabelle at the Serpukhov accelerator, 1 943 interactions at 50 GeV/ c and 8 959 at 69 GeV/ c have been observed. Topological cross sections and charged multiplicity distributions are presented. The average charged multiplicities found are respectively 5.32 ± 0.13 and 5.89 ± 0.07.

1 data table

2PRONG INELASTIC CROSS SECTIONS DERIVED BY SUBTRACTION OF OTHER PRONG CROSS SECTIONS AND KNOWN ELASTIC MEASUREMENTS FROM THE TOTAL.


Observation of the reaction pi- p ---> anti-p d from 4 to 6 gev/c

Pawlicki, A.J. ; Ayres, D.S. ; Diebold, R. ; et al.
Phys.Rev.Lett. 31 (1973) 665-667, 1973.
Inspire Record 83780 DOI 10.17182/hepdata.21336

Differential cross sections have been measured for the reaction π−p→p¯d. At 4 GeV/c the total cross section is 0.58 ± 0.08 μb with an angular distribution consistent with isotropy. At 5 GeV/c a pronounced forward dip occurs. In contradiction to simple baryon-exchange models, the cross section is found to be an order of magnitude smaller than that for the line-reversed reaction pp→π+d. Upper limits for π−d→p¯t were also found.

2 data tables

No description provided.

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Comparison of particle-antiparticle elastic scattering from 3 to 6 gev/c

Ambats, I. ; Ayres, D.S. ; Diebold, R. ; et al.
Phys.Rev.Lett. 29 (1972) 1415-1419, 1972.
Inspire Record 84577 DOI 10.17182/hepdata.21445

Differential cross sections for π±p, K±p, pp, and p¯p elastic scattering were measured at 3, 3.65, 5, and 6 GeVc for momentum transfers from 0.03 to 1.5 GeV2 using the Argonne effective mass spectrometer. Particular attention was paid to the relative particle-antiparticle normalization. The crossover points are consistent with no energy dependence, average values being 0.14 ± 0.03, 1.190 ± 0.005, and 0.160 ± 0.007 GeV2 for π's, K's, and protons, respectively.

1 data table

No description provided.


On helicity conservation in the reaction pi- p ---> a1 p at 4.45 gev/c

Beketov, G.V. ; Zombkovsky, S.M. ; Kaidalov, A.B. ; et al.
Nucl.Phys.B 59 (1973) 265-272, 1973.
Inspire Record 83967 DOI 10.17182/hepdata.32538

Helicity conservation in the reaction π − p → pA 1 at 4.45 GeV/ c has been studied using 50 cm and 55 cm liquid hydrogen bubble chambers. In the Jackson and the helicity frames the dependence of the ϱ matrix elements on the four-momentum transfer squared to the proton ( t ) for A 1 maximum decay has been calculated. The obtained data are in a good agreement with t -channel helicity conservation. The t -channel dependence of the ϱ matrix elements in the mentioned frames is in good agreement with that calculated using the Regge π-pole exchange model (it is suggested that the A 1 maximum nature is explained by a kinematical effect of the Deck type).

1 data table

No description provided.


Systematic study of pi+- p, k+- p, p p, and anti-p p forward elastic scattering from 3 to 6 gev/c

Ambats, I. ; Ayres, D.S. ; Diebold, R. ; et al.
Phys.Rev.D 9 (1974) 1179-1209, 1974.
Inspire Record 92992 DOI 10.17182/hepdata.3409

Measurements of π±p, K±p, pp, and p¯p elastic scattering are presented for incident momenta of 3, 3.65, 5, and 6 GeVc and momentum transfers typically 0.03 to 1.8 GeV2. The angle and momentum of the scattered particle were measured with the Argonne Effective Mass Spectrometer for 300 000 events, yielding 930 cross-section values with an uncertainty in absolute normalization of ±4%. Only the K+ and proton data show any significant change in slope of the forward diffraction peak with incident momentum. The particle-antiparticle crossover positions are consistent with no energy dependence, average values being 0.14 ± 0.03, 0.190 ± 0.006, and 0.162 ± 0.004 GeV2 for π' s, K' s, and protons, respectively; these errors reflect both statistics and the ±1.5% uncertainty in particle-antiparticle relative normalization. Differences between particle and antiparticle cross sections isolate interference terms between amplitudes of opposite C parity in the t channel; these differences indicate that the imaginary part of the odd-C nonflip-helicity amplitude has a J0(r(−t)12) structure for −t<0.8 GeV2, as predicted by strong absorption models. The cross-section differences for K± and proton-antiproton are in qualitative agreement with the predictions of ω universality, the agreement improving with increasing energy. The corresponding quark-model predictions relating the π± and K± differences failed by more than a factor of 2. We have combined our π± cross sections with other data to better determine the πN amplitudes in a model-independent way; results of this analysis are presented.

18 data tables

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Systematic Study of K+- Charge Exchange from 3-GeV/c to 6-GeV/c

Diebold, R. ; Ayres, D.S. ; Greene, A.F. ; et al.
Phys.Rev.Lett. 32 (1974) 904, 1974.
Inspire Record 89016 DOI 10.17182/hepdata.21284

Differential cross sections for K−p→K¯0n and K+n→K0p have been measured at 3, 4, and 6 GeV/c using a data sample of 6000 events. Contrary to simple exchange-degenerate models, the ratio of K+ to K− cross sections was found to be approximately 1.35, with little dependence on either s or t. Both reactions show a shallow dip near the forward direction, suggesting the importance of spin-flip amplitudes.

3 data tables

No description provided.

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LARGE -T CONTRIBUTIONS (TYPICALLY 12 PCT) ESTIMATED FROM BUBBLE-CHAMBER DATA.


phi Meson Production in pi- p and K- p Interactions from 3-GeV/c to 6-GeV/c

Ayres, D.S. ; Diebold, R. ; Greene, A.F. ; et al.
Phys.Rev.Lett. 32 (1974) 1463, 1974.
Inspire Record 89228 DOI 10.17182/hepdata.51356

Cross sections and density-matrix elements for π−p→ϕn have been measured for - −t≲1.5 GeV2 at 3, 4, 5, and 6 GeV/c, using the Argonne effective-mass spectrometer to observe the decay ϕ(1019)→K+K−. This is the first observation of the reaction in this energy range. The remarkably flat differential cross section at 4 GeV/c and the strong energy dependence suggest a production mechanism not normally seen at these energies. Data on K−p→ϕΛ and K−p→ϕΣ0 from the same experiment are also presented.

2 data tables

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Measurement of the Polarization Parameter in Small Angle Proton Proton Elastic Scattering at 6-GeV/c

Rust, D.R. ; Crittenden, R.R. ; Heinz, R.M. ; et al.
Phys.Lett.B 58 (1975) 114-116, 1975.
Inspire Record 99058 DOI 10.17182/hepdata.27810

The polarization parameter in pp elastic scattering was measured at 6 GeV/ c with fine t resolution for 0.02 < − t < 0.5 GeV 2 using a polarized proton beam with Effective Mass Spectrometer at the Zero Gradient Synchrotron. The polarization rises like √− t in the interval 0.02 < − t < 0.1 GeV 2 , No statistical significant structure was found in this region of momentum transfer.

1 data table

No description provided.


Measurement of the Proton-Neutron Elastic Scattering Polarization from 2-GeV/c to 6-GeV/c

Diebold, R. ; Ayres, D.S. ; Kramer, S.L. ; et al.
Phys.Rev.Lett. 35 (1975) 632, 1975.
Inspire Record 99560 DOI 10.17182/hepdata.21193

Left-right asymmetries from a deuterium target in a polarized-proton beam were observed with the Argonne National Laboratory effective-mass spectrometer. Results were obtained for both pp and pn elastic scattering from −t=0.15 to 1.0 GeV2 at 2, 3, 4, and 6 GeV/c. For −t≲0.6 GeV2 the pn polarization was found to have the same sign as for pp, but with faster energy dependence, the ratio P(pn)P(pp) at −t=0.3 GeV2 falling from 0.78±0.02 at 2 GeV/c to 0.22±0.03 at 6 GeV/c.

4 data tables

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Correlations Associated with Particles Produced at Small Angles in p p Collisions at the CERN ISR

The CHLM collaboration Albrow, M.G. ; Barber, D.P. ; Benz, P. ; et al.
Nucl.Phys.B 102 (1976) 275-296, 1976.
Inspire Record 2886 DOI 10.17182/hepdata.36078

Data on correlations between momentum analysed protons, pions or K mesons, and charged particles produced in pp collisions at the CERN ISR are presented. The charged particles were detected in a ∼4 π scintillation counter hodoscope. The pseudo-rapidity distributions are well described by production within the limits of cylindrical phase space, with negative kaons and antiprotons yielding narrower distributions than protons, pions and positive kaons. The azimuthal distributions show symmetry around the t -channel axis in the rest frame of the recoiling mass M x in pp → aX (a = detected proton, pion, positive kaon).

8 data tables

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Inelastic Diffractive Scattering at the CERN ISR

The CHLM collaboration Albrow, M.G. ; Bagchus, A. ; Barber, D.P. ; et al.
Nucl.Phys.B 108 (1976) 1-29, 1976.
Inspire Record 3424 DOI 10.17182/hepdata.8494

The properties of the diffractive peak observed in the mass spectra of systems recoiling against observed high-momentum protons emerging from pp collisions at the CERN ISR have been investigated. The cross sections in this peak have been found to have a steep t dependence which flattens out as | t | increases. The high mass side of the peak varies approximately as 1/ M 2 (where M is the missing mass of the recoiling system) and scales well in terms of the variable M 2 / s . The position of the maximum has been observed to move to lower values of M 2 / s as the kinematic boundary of this variable decreases with increasing s . The measured cross sections, integrated up to M 2 / s =0.05, rise by (15±5)% over the s range 549 to 1464 GeV 2 .

191 data tables

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Phi-Meson Production in the Reactions pi+- n --> K- K+ n at 6-GeV/c

Cohen, Daniel H. ; Ayres, D.S. ; Diebold, R. ; et al.
Phys.Rev.Lett. 38 (1977) 269, 1977.
Inspire Record 110508 DOI 10.17182/hepdata.21019

A sample of 1200 ϕ mesons produced in the Zweig-rule-forbidden reactions π±N→ϕN shows a flat t distribution (slope=1.7 ± 0.2 GeV−2) and a cross section suppressed by 0.0032±0.0004 relative to π−p→ωn. Natural-parity-exchange ω and ϕ production have similar t dependences, while ω and ϕ production by unnatural-parity exchange differ markedly. Interference between the ϕ and the underlying K¯K S wave indicates substantial nucleon-spin incoherence between the amplitudes for ϕ and S-wave production.

3 data tables

Axis error includes +- 10/10 contribution (RES-DEF(RES=PHI,BACK=CORRECTED)).

Axis error includes +- 10/10 contribution (RES-DEF(RES=PHI,BACK=CORRECTED)).

STATISTICAL ERRORS ONLY.


Comparative Study of rho0, omega, K* (890) and anti-K* (890) Production by Charge Exchange

Wicklund, A.B. ; Ayres, D.S. ; Diebold, R. ; et al.
Phys.Rev.D 17 (1978) 1197, 1978.
Inspire Record 120816 DOI 10.17182/hepdata.24436

We present cross sections and density-matrix elements from a high-statistics study of the reactions π−p→ρ0n, K−p→K¯*0(890)n, and K+n→K*0(890)p, at 3, 4, and 6 GeV/c and four-momentum transfer squared to the recoil nucleon −t<~0.9 GeV2. The experiment was carried out at the Argonne Zero Gradient Synchrotron using the effective-mass spectrometer. In the same experiment, we have measured the ρ−ω interference cross sections by comparison of the two reactions π−p→π−π+n and π+n→π+π−p, to which the interference terms contribute with opposite signs. We examine the systematics of ρ0 production: In the s channel we find little shrinkage with energy of the helicity-0 cross sections, which are presumably dominated by π exchange; the helicity-1 cross sections exhibit considerable shrinkage for unnatural-parity exchange, and antishrinkage for natural-parity exchange. The K*0 and K¯*0 production observables exhibit significant differences, especially in the helicity-1 states. These differences are due to interference between even- and odd-G-parity exchange amplitudes and they are related by SU(3) symmetry to ρ−ω interference effects and to the ρ0 and ω production observables. It is shown that exchange-degeneracy-breaking effects satisfy SU(3) symmetry and can be explained qualitatively in the frame-work of SU(3)-symmetric, strongly absorbed Regge-pole models. The results of our amplitude analysis are compared with previous phenomenological analyses and model predictions.

9 data tables

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Polarization Parameter for Nucleon-Nucleon Elastic Scattering at 11.8-GeV/c

Kramer, S.L. ; Ayres, D.S. ; Cohen, Daniel H. ; et al.
Phys.Rev.D 17 (1978) 1709, 1978.
Inspire Record 122176 DOI 10.17182/hepdata.24427

Data are presented on the polarization parameter in pp and pn elastic scattering at 11.8 GeV/c for four-momentum transfers −t=0.15 to 0.9 GeV2. In contrast to lower energies where the pn polarization is positive, it is slightly negative at 11.8 GeV/c; averaging the data from −t=0.18 to 0.5 GeV2 we find P(pn)=(−0.9±0.5)%, to be compared with P(pp)=(5.6±0.8)%. These data, combined with our previous data at lower energies, show that the I=0 single-flip exchange amplitude has an anomalously rapid energy dependence.

1 data table

No description provided.


Charged Pion Production in 32-{GeV}/$c K^+ p$ Interactions

The French-Soviet & CERN-Soviet collaborations Ajinenko, I.V. ; Belokopitov, Y.A. ; Chliapnikov, P.V. ; et al.
Z.Phys.C 4 (1980) 181, 1980.
Inspire Record 141743 DOI 10.17182/hepdata.16626

Final data on topological cross sections are presented. Inclusive single particle distributions for the reactionsK+p→ π±X at 32 GeV/c are discussed and compared with data at lower energies. Early scaling in the fragmentation regions is confirmed, while cross sections in th central region continue to rise with energy even faster than inpp interactions. Thex-andpT-dependence of the π+/π− ratio inK+p interactions is discussed and a comparison of reactionsK+p→ π±X andK−p→ π±X at 32 GeV/c is made in the context of constituent models. We also present transverse momentum distributions, show prominent seagull effects and study how they are influenced by resonance production.

4 data tables
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Cross-sections and Multiplicity Distributions for $K^+ p$ Interactions at 70-{GeV}/$c$

Barth, M. ; De Clercq, C. ; De Wolf, E. ; et al.
Z.Phys.C 2 (1979) 285, 1979.
Inspire Record 141693 DOI 10.17182/hepdata.2107

Cross sections and charged multiplicity distributions forK+p interactions at 70 GeV/c are presented and compared withK+p data at other energies. Comparisons are also made with available π+p,pp, andK−p data.

2 data tables

No description provided.

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π+ meson production in low-energy proton collisions with carbon and copper nuclei

Akimov, Yu.K. ; Gajsak, I.I. ; Guber, F.F. ; et al.
JINR-1-80-294, 1980.
Inspire Record 1395696 DOI 10.17182/hepdata.39684

Differential and double differential cross sections of positive pion production by 240 MeV protons on carbon and copper nuclei are measured. The energy dependence of differential cross section for copper nucleus at 90 deg angle within the 240-500 MeV energy range of protons and angular dependence of the integrated differential cross section are obtained. It is shown that the differential cross section at 250 MeV is 80 times less than that at 585 MeV

4 data tables

No description provided.

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Differential Cross-sections for $\pi^\pm$ Production at 0-degrees From Proton Proton and Proton - Deuteron Collisions at 1-{GeV}

Abaev, V.V. ; Gridnev, A.B. ; Koptev, V.P. ; et al.
LENINGRAD-80-569, 1980.
Inspire Record 154994 DOI 10.17182/hepdata.37950

None

3 data tables

Axis error includes +- 15/15 contribution (DUE TO DATA NORMALISATION ON CROSS SECTION,WHICH IS DEFINED WITH 15% ACCURACY).

Axis error includes +- 15/15 contribution (DUE TO DATA NORMALISATION ON CROSS SECTION,WHICH IS DEFINED WITH 15% ACCURACY).

Axis error includes +- 15/15 contribution (DUE TO DATA NORMALISATION ON CROSS SECTION,WHICH IS DEFINED WITH 15% ACCURACY).


Polarization in Charge Exchange Reaction $\pi^- p \to \pi^0 n$ in Small Momentum Transfer Range at 40-{GeV}/$c$

Apokin, V.D. ; Avvakumov, I.A. ; Bagaturiya, Yu.Sh. ; et al.
Experientia Suppl. 38 (1981) 554, 1981.
Inspire Record 154047 DOI 10.17182/hepdata.11048

None

2 data tables

AVERAGE TARGET POLARIZATION WAS 76 +- 3 PCT.

No description provided.


Multiplicity of Charged Particles Produced in Pi- and $K^-$ Collisions With Nuclei in Streamer Chamber at 40-{GeV}/c. (In Russian)

The RISK collaboration Andreev, E.M. ; Bohm, J. ; Bahr, J. ; et al.
Sov.J.Nucl.Phys. 35 (1982) 405, 1982.
Inspire Record 158564 DOI 10.17182/hepdata.39550

None

18 data tables

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Energy Dependence of the Yields of Cumulative Protons and Neutrons in $\pi^-$ a Interactions

Bayukov, Yu.D. ; Gavrilov, V.B. ; Goryainov, N.A. ; et al.
Sov.J.Nucl.Phys. 34 (1981) 437-439, 1981.
Inspire Record 171693 DOI 10.17182/hepdata.17790

None

1 data table

No description provided.


High $p_T$ Hadron Production in Photon - Photon Collisions

The TASSO collaboration Brandelik, R. ; Braunschweig, W. ; Gather, K. ; et al.
Phys.Lett.B 107 (1981) 290-296, 1981.
Inspire Record 167417 DOI 10.17182/hepdata.31027

We have studied the properties of hadron production in photon-photon scattering with tagged photons at the e + e − storage ring PETRA. A tail in the p T distribution of particles consistent with p T −4 has been observed. We show that this tail cannot be due to the hadronic part of the photon. Selected events with high p T particles are found to be consistent with a two-jet structure as expected from a point-like coupling of the photons to quarks. The lowest-order cross section predicted for γγ → q q , σ = 3 Σ e q 4 · σ γγ → μμ , is approached from above by the data at large transverse momenta.

1 data table

No description provided.


Exclusive Proton - Anti-proton Production in Two Photon Collisions

The TASSO collaboration Brandelik, R. ; Braunschweig, W. ; Gather, K. ; et al.
Phys.Lett.B 108 (1982) 67-70, 1982.
Inspire Record 167679 DOI 10.17182/hepdata.31000

Production of proton-antiproton pairs by two-photon scattering has been observed at the electron-position storage ring PETRA. A total of eight proton-antiproton pairs have been identified using the time-of-flight technique. We have measured a total cross section of 4.5 ± 0.8 nb in the photon-photon c.m. energy range 2.0–2.6 GeV.

1 data table

No description provided.


Polarization in Charge Exchange Reaction $\pi^- p \to \pi^0 n$ at 40-{GeV}/$c$ for the Four Momentum Transfer Range $0 < T < 2$-{GeV}/$c^2$

Apokin, V.D. ; Avvakumov, I.A. ; Bagaturiya, Yu.Sh. ; et al.
Z.Phys.C 15 (1982) 293, 1982.
Inspire Record 169455 DOI 10.17182/hepdata.41256

The results on measuring polarization in charge exchange reaction π−+p→π0+n at 40 GeV/c are presented for the 4-momentum transfer range from 0 up to 2 (GeV/c)2. At |t|≦0.4 (GeV/c)2 the polarization has a positive sign. In the “crossover” region of π± elastic scattering a possible minimum in the polarization behaviour has been seen for the first time. the polarization is zero within the statistical accuracy near this point. In the “deep” region of the charge-exchange differential cross-section the polarization has a negative sign. The presented data are not in agreement with the modern theoretical models.

1 data table

$\pi^0$ Production by $e^+ e^-$ Annihilation at 14-{GeV} and 34-{GeV} Center-of-mass Energy

The TASSO collaboration Brandelik, R. ; Braunschweig, W. ; Gather, K. ; et al.
Phys.Lett.B 108 (1982) 71-76, 1982.
Inspire Record 168232 DOI 10.17182/hepdata.31018

The process e + e − → π 0 + anything has been measured at c.m. energies of 14 and 34 GeV for π 0 energies between 0.5 and 4 GeV. The ratio of π 0 to π ± production for π momenta between 0.5 and 1.5 GeV/ c is measured to be 2 σ ( π 0 )/ [ σ ( π + ) + σ ( π − )] = 1.3 ± 0.4 (1.2 ± 0.4) at 14 (34) GeV. The scaled cross section ( s / μ )d σ /d x when compared with lower energy (4.9–7.4 GeV) π 0 data indicates a substantial scaling violation.

3 data tables

COMPARISON OF PI0 WITH CHARGED PION CROSS SECTIONS (SCALED BI 1/S TO SAME ENERGIES).

No description provided.

No description provided.


Charge Asymmetry and Weak Interaction Effects in $e^+ e^- \to \mu^+ \mu^-$ and $e^+ e^- \to \tau^+ \tau^-$

The TASSO collaboration Brandelik, R. ; Braunschweig, W. ; Gather, K. ; et al.
Phys.Lett.B 110 (1982) 173-180, 1982.
Inspire Record 176719 DOI 10.17182/hepdata.6699

We have measured, at an average centre-of-mass energy of 34.22 GeV a forward-backward charge asymmetry in the reaction e + e − → μ + μ − of value −0.161 ± 0.032. This demonstrates the existence of an axial vector neutral current with coupling strength of g e a g μ a =0.53 ± 0.10. We have also obtained a limit on the vector coupling strength of g e v g μ v <0.12. The Weinberg angle is found to be sin 2 θ W =0.29 +0.09 −0.11 . From the reaction e + e − → τ + τ − we have found g e a g τ a <0.34, g e v g τ v <0.55.

7 data tables

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Elastic Scattering Measurement of the Negative Pion Radius

Dally, E.B. ; Hauptman, J.M. ; Kubic, J. ; et al.
Phys.Rev.Lett. 48 (1982) 375-378, 1982.
Inspire Record 177923 DOI 10.17182/hepdata.20609

A new measurement of the elastic scattering of 250-GeV/c negative pions by electrons provides form-factor results from 0.0368<q2<0.0940 (GeV/c)2. These measurements determine the mean square pion radius to be 〈rπ2〉=0.439±0.030 fm2 or 〈rπ2〉12=0.663±0.023 fm. Comparisons are made with previous elastic-scattering experiments as well as with results obtained from electroproduction experiments, e+e− annihilation experiments, and phenomenological analyses.

1 data table

No description provided.


A Measurement of Sigma(tot) (e+ e- ---> Hadrons) for CM Energies Between 12.0-GeV and 36.7-GeV

The TASSO collaboration Brandelik, R. ; Braunschweig, W. ; Gather, K. ; et al.
Phys.Lett.B 113 (1982) 499-508, 1982.
Inspire Record 176887 DOI 10.17182/hepdata.6666

The ration R = σ (e + e − → hadrons) σ μμ was measured between 12.0 and 36.7 GeV c.m. energy W with a precision of typically ± 5.2%. R is found to be constant with an average R = 4.01 ± 0.03 (stat) ± (syst.) for W ⩾ 14 GeV. Quarks are found to be point-like, the mass parameter describing a possible quark form-factor being larger than 186 GeV. Fits including QCD corrections and a weak neutral-current contribution are presented.

4 data tables

DATA OF RUNPERIOD 1.

DATA OF RUNPERIOD 2.

R MEASURED IN SCANNING MODE.

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Charged Pion Production in $e^+ e^-$ Annihilation at 14-{GeV}, 22-{GeV} and 34-{GeV} Center-of-mass Energy

The TASSO collaboration Brandelik, R. ; Braunschweig, W. ; Gather, K. ; et al.
Phys.Lett.B 113 (1982) 98-104, 1982.
Inspire Record 176886 DOI 10.17182/hepdata.30892

The inclusive production of π ± mesons in e + e − annihilation has been measured at c.m. energies of 14, 22 and 34 GeV for pion momenta between 0.3 ans 10 GeV/ c . The fraction of pions among the charged hadrons is above 90% at 0.4 GeV/ c and decreases to about 50% at high momenta. The scaled cross sections ( s β ) d σ d x at 14, 22 and 34 GeV as well as the 5.2 GeV data from DASP have a rather similar x dependence. After integration over the x range from 0.2 to 0.6 the cross sections indicate a monotonic decrease with increasing centre-of-mass energy.

16 data tables

PION FRACTIONS IDENTIFIED BY INNER TOF COUNTERS (ITOF). ERRORS SHOWN ARE STATISTICAL ONLY.

PION FRACTIONS IDENTIFIED BY INNER TOF COUNTERS (ITOF). ERRORS SHOWN ARE STATISTICAL ONLY.

PION FRACTIONS IDENTIFIED BY INNER TOF COUNTERS (ITOF). ERRORS SHOWN ARE STATISTICAL ONLY.

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Scale Breaking in Inclusive Charged Particle Production by $e^+ e^-$ Annihilation

The TASSO collaboration Brandelik, R. ; Braunschweig, W. ; Gather, K. ; et al.
Phys.Lett.B 114 (1982) 65, 1982.
Inspire Record 177174 DOI 10.17182/hepdata.30894

The scale cross section s d σ d x p for inclusive charged-particle production in e + e − annihilation has been studied for c.m. energies W between 12.0 and 36.7 GeV. Scale breaking is observed. For x p >0.2 the cross section decreases by ≈20% when W increases from 14 to 35 GeV. The production angular distribution was used to separate the longitudinal and transverse cross-section contributions and to determine the ratio of the structure functions m W 1 and v W 2 .

3 data tables

DATA FROM TABLE 1A IN PREPRINT DESY-82-013.

DATA FROM TABLE 1B IN PREPRINT DESY-82-013.

DATA FROM TABLE 1C IN PREPRINT DESY-82-013. TOTAL CROSS SECTION TAKEN FROM EARLIER TASSO MEASUREMENTS, PL 113B, 499. NORMALIZED CROSS SECTION IS NOT SUBJECT TO THE 4.5 PCT NORMALIZATION ERROR AND A POSSIBLE 2-3 PCT CONTRIBUTION FROM THE WEAK NEUTRAL CURRENT IS TAKEN CARE OF.


OBSERVATION OF POLARIZATION IN REACTION pi- p ---> eta n AT 40-GeV/c

Apokin, V.D. ; Avvakumov, I.A. ; Borisov, N.S. ; et al.
BNL Spin Sympos.1982:118, 1982.
Inspire Record 178780 DOI 10.17182/hepdata.41130

None

1 data table

No description provided.


Electroweak Coupling Constants in the Leptonic Reactions e+ e- ---> e+ e- and e+ e- ---> mu+ mu- and Search for Scalar Leptons

The TASSO collaboration Brandelik, R. ; Braunschweig, W. ; Gather, K. ; et al.
Phys.Lett.B 117 (1982) 365-371, 1982.
Inspire Record 178495 DOI 10.17182/hepdata.6669

A high statistics experiment was performed on Bhabha scattering at energies between 14 and 34 GeV. Good agreement with QED was observed. The combined data on Bhabha scattering and μ pair production were found to agree with the standard theory of electroweak interaction giving sin 2 θ = 0.27 −0.07 +0.06 . Assuming for the Z 0 mass a value of 90 GeV the leptonic weak coupling constants were determined to g V 2 = −0.04 ± 0.06 and g A 2 = 0.35 ± 0.09. A search for scalar leptons sets lower limits on the mass of scalar electrons of M s e > 16.6 GeV and of scalar muons of M s μ > 16.4 GeV.

2 data tables

No description provided.

No description provided.


Inclusive $\phi$ Production in $K^+ p$ Interactions at 70-{GeV}/$c$

The Brussels-CERN-Genoa-Mons-Nijmegen-Serpukhov collaboration Barth, M. ; De Clercq, C. ; De Wolf, E.A. ; et al.
Phys.Lett.B 117 (1982) 267-271, 1982.
Inspire Record 178885 DOI 10.17182/hepdata.41158

We present results on inclusive φ meson production in K + p interactions at 70 GeV/ c in the kaon fragmentation x >0.2 region. Comparison with other data on φ meson production in K ± and p induced reactions provides evidence that the strange valence-quark fragmentation or recombination processes play the dominant role in the K ± → φ transitions. Arguments are presented that the kaon valence strange s -quark carries a much higher momentum fraction than the u-quark. Evidence for the previously observed narrow φπ + state at mass ∼2.1 GeV is discussed.

4 data tables
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Inclusive $\bar{\Lambda}$ Polarization in $K^+ p$ Interactions at 32-{GeV}/$c$ and 70-{GeV}/$c$

The Soviet-CERN collaboration Azhinenko, I.V. ; Amaglobeli, N.S. ; Baland, J.F. ; et al.
Phys.Lett.B 121 (1983) 183, 1983.
Inspire Record 179546 DOI 10.17182/hepdata.41221

We present results on the inclusive polarization of Λ hyperons produced in K + p interactions at 32 and 70 GeV/ c . A large positive Λ polarization is observed in the kaon fragmentation region. The polarization is energy independent, increases strongly with increasing x , but shows essentially no p T -dependence.

8 data tables
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A Study of $K^+ p$ Elastic Scattering and the Reaction $K^+ p \to K^+ p \pi^+ \pi^-$ at 70-{GeV}/$c$

The Brussels-Genoa-Mons-Nijmegen-Serpukhov-CERN collaboration Barth, M. ; Wolf, A.E. De ; Johnson, D.P. ; et al.
Z.Phys.C 16 (1982) 111, 1982.
Inspire Record 181354 DOI 10.17182/hepdata.41205

Results are presented onK+p elastic scattering and on the reactionK+p→K+pπ+π− at 70 GeV/c. For the

9 data tables
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Inclusive $\rho^0$ Production in $e^+ e^-$ Annihilation at High-energy

The TASSO collaboration Brandelik, R. ; Braunschweig, W. ; Gather, K. ; et al.
Phys.Lett.B 117 (1982) 135-140, 1982.
Inspire Record 179022 DOI 10.17182/hepdata.6664

We have observed ϱ 0 production in e + e − annihilation to hadrons at high energies. The differential cross section at a centre of mass energy W , of 34 GeV, is presented. In the range 0.2< x < 0.7, we measure 0.33 ± 0.06 (stat.) ± 0.07 (syst.), 0.22 ± 0.06 ± 0.05 and 0.22 ± 0.02 ± 0.05 ϱ 0 /event at W = 14, 22 and 34 GeV respectively.

10 data tables

No description provided.

No description provided.

INTEGRATION OVER RESTRICTED X RANGE.

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High Precision Measurement of the $\Upsilon$ Meson Mass

Artamonov, A.S. ; Baru, S.E. ; Blinov, A.E. ; et al.
Phys.Lett.B 118 (1982) 225, 1982.
Inspire Record 178785 DOI 10.17182/hepdata.37137

A high precision measurement of the υ-meson mass has been performed at the storage ring VEPP-4 using the MD-1 detector. The resonance depolarization method has been used for the absolute calibration of the beam energy that allowed to improve the accuracy of υ-mass measurement by a factor of ten. The following mass value has been obtained: M = 9459.7 ± 0.6 MeV.

1 data table

No description provided.


Energy and Quantum Number Flow in $K^+ p$ and $\pi^+ p$ Interactions at 32-{GeV}/$c$ and 70-{GeV}/$c$

The Brussels-Serpukhov-Tbilisi-Genoa-Mons-Nijmegen-CERN collaboration Azhinenko, I.V. ; Belokopytov, Yu.A. ; Vorobev, A.P. ; et al.
Z.Phys.C 16 (1983) 291, 1983.
Inspire Record 181635 DOI 10.17182/hepdata.10881

Energy, charge and strangeness flow inK+p interactions at 32 and 70 GeV/c, and π+p interactions at 32 GeV/c are studied in terms of the angular variable λ=|x|/pT. The data ondQ/dλ anddE/dλ show only a weak indication of scale breaking between 32 and 70 GeV/c. For inclusive “non-diffractive”, inclusive “diffractive” and exclusive “non-diffractive” jets, the fraction of charge in any angular region ΔΩ away from the central region is found to be proportional to the energy fraction in the same interval. The data ondQ/dE versus λ are compatible with some versions of dual-sheet models and agree also with the LUND Monte-Carlo model. The data are also compared with\(v(\bar v)p\) interactions in BEBC. In exclusive channels the average ratiodQ/dS=0.78±0.04 is consistent, in the framework of fragmentation models, with a larger probability for the fragmentation of the\(\bar s\)-valence quark than theu-valence quark in theK+-meson.

16 data tables

CHARGE FLOW IN NONDIFFRACTIVE PROTON-LIKE AND KAON-LIKE JETS.

CHARGE FLOW IN NONDIFFRACTIVE PROTON-LIKE AND KAON-LIKE JETS.

CHARGE FLOW IN NONDIFFRACTIVE PROTON-LIKE AND KAON-LIKE JETS.

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Angular Correlations in gamma Gamma ---> rho0 rho0 Near Threshold

The TASSO collaboration Althoff, M. ; Braunschweig, W. ; Gather, K. ; et al.
Z.Phys.C 16 (1982) 13, 1982.
Inspire Record 180755 DOI 10.17182/hepdata.16415

We present an analysis ofρ0ρ0 production by two photons in theρ0ρ0 invariant mass range from 1.2 to 2.0 GeV. From a study of the angular correlations in the process γγ→ρ0ρ0→π−π+π− we exclude a dominant contribution fromJP=0− or 2− states. The data indicate sizeable contributions fromJP=0+ for four pion massesM4π<1.7 GeV and fromJP=2+ forM4π>1.7 GeV. The data are also well described by a model with isotropic production and uncorrelated isotropic decay of theρ0,s. The cross section stays high below the nominalρ0ρ0 threshold, i.e.M4π<1.5 GeV. The matrix element forρ0ρ0 production is found to decrease steeply with increasingM4π. Upper limits for the couplings of the ι(1440) and Θ(1640) to γγ andρ0ρ0 are given:Γ(ι→γγ)·B(ι→ρ0ρ0)<1.0 keV andΓ(Θ→γγ)

2 data tables

ASSUMING ISOTROPIC RHO0 RHO0 PRODUCTION AND ISOTROPIC RHO DECAY.

CROSS SECTIONS FOR DIFFERENT SPIN-PARITY CONTRIBUTIONS.


Charged Hadron Composition of the Final State in e+ e- Annihilation at High-Energies

The TASSO collaboration Althoff, M. ; Brandelik, R. ; Braunschweig, W. ; et al.
Z.Phys.C 17 (1983) 5-15, 1983.
Inspire Record 181470 DOI 10.17182/hepdata.2143

The inclusive production of π± andK± mesons and of protons and antiprotons ine+e− annihilation has been measured at c.m. energies ofW=14, 22 and 34GeV. Using time of flight measurements and Cerenkov counters the full momentum range has been covered. Differential cross sections and total particle yields are given. At particle momenta of 0.4 GeV/c more than 90% of the charged hadrons are pions. With increasing momentum the fraction of pions among the charged hadrons decreases. AtW=34 GeV and a momentum of 5 GeV/c the particle fractions are approximately π±:K±:p,\(\bar p = 0.55:0.3:0.15\). On average an event atW=34 GeV contains 10.3±0.4π±, 2.0±0.2K± and 0.8±0.1p,\(\bar p\). In addition, we present results on baryon correlations using a sample of events where two or more protons and/or antiprotons are observed in the final state.

27 data tables

No description provided.

No description provided.

No description provided.

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Production of $K \bar{K}$ Pairs in Photon-photon Collisions and the Excitation of the Tensor Meson F-prime (1515)

The TASSO collaboration Althoff, M. ; Brandelik, R. ; Braunschweig, W. ; et al.
Phys.Lett.B 121 (1983) 216-222, 1983.
Inspire Record 181468 DOI 10.17182/hepdata.30814

We have observed exclusive production of K + K − and K S O K S O pairs and the excitation of the f′(1515) tensor meson in photon-photon collisions. Assuming the f′ to be production in a helicity 2 state, we determine Λ( f ′ → γγ) B( f ′ → K K ) = 0.11 ± 0.02 ± 0.04 keV . The non-strange quark of the f′ is found to be less than 3% (95% CL). For the θ(1640) we derive an upper limit for the product Λ(θ rarr; γγ K K ) < 0.03 keV (95% CL ) .

2 data tables

Data read from graph.. Errors are the square roots of the number of events.

Data read from graph.. Errors are the square roots of the number of events.


MEASUREMENT OF CROSS-SECTIONS OF MESON PAIR PRODUCTION IN NUCLEON NUCLEON COLLISIONS BELOW 1-GEV AND ISOSPIN ANALYSIS. (IN RUSSIAN)

Dakhno, L.g. ; Kravtsov, A.v. ; Lobachev, E.a. ; et al.
Yad.Fiz. 37 (1983) 907-914, 1983.
Inspire Record 194256 DOI 10.17182/hepdata.17742

None

1 data table

No description provided.


ANALYZING POWER IN THE REACTION P P ---> D PI+ FOR BEAM MOMENTA FROM 1.17-GEV/C TO 1.96-GEV/C

Corcoran, M.d. ; Calkin, M.m. ; Hoftiezer, J.h. ; et al.
Phys.Lett.B 120 (1983) 309-313, 1983.
Inspire Record 190882 DOI 10.17182/hepdata.30825

The analyzing power A y 0 in the reaction p↑p→dπ + has been measured using the polarized proton beam at Argonne National Laboratory's zero gradient synchrotron. Data were taken at beam momenta of 1.17, 1.47, 1.70, and 1.96 GeV/ c and for pion center of mass angles from 8° to 163°.

1 data table

No description provided.


D*+- Production by e+ e- Annihilation Near 34.4-GeV Center-Of-Mass Energy

The TASSO collaboration Althoff, M. ; Braunschweig, W. ; Gather, K. ; et al.
Phys.Lett.B 126 (1983) 493-498, 1983.
Inspire Record 196842 DOI 10.17182/hepdata.30721

D ∗± production via e + e − →D ∗± X has been measured at an average CM energy of 34.4 GeV. The D ∗± energy spectrum is hard, with a maximum near χ = 0.6. The size of the D ∗ cross section, R D ∗ = σ( e + e − → D ∗ X ) σ μμ = 2.50 ± 0.64 ± 0.88 (assuming R D ∗0 = R D ∗+ ) indicates that a large fraction of charm quark production yields D ∗ mesons. The D ∗± angular distribution exhibits a forward—backward asymmetry, A = −0.28 ± 0.13. This is consistent with that expected in the standard theory for weak neutral currents and leads to | g A c | = 0.89 ± 0.44 for the axial vector coupling of the charm quark.

3 data tables

ASSUMES EQUAL RATES FOR CHARGED AND NEUTRAL D*'S. ONLY CHARGED ARE DETECTED.

DATA PEAKS AT X=0.6 TO 0.8.

ASYMMETRY MEASUREMENT. THETA IS THE ANGLE BETWEEN THE E- AND THE D*.


CESIUM-IODINE DESIGNATED NUCLEUS.

CESIUM-IODINE DESIGNATED NUCLEUS.

CESIUM-IODINE DESIGNATED NUCLEUS.


DELTA ISOBAR EXCITATION IN CARBON NUCLEI AT 4.4-GEV/C - 10.7-GEV/C IN CHARGE EXCHANGE REACTION (HE-3, T).

The DUBNA-MOSCOW-KIEV-DUSHANBE collaboration Ableev, V.G. ; Kobushkin, A.P. ; Kurepin, A.B. ; et al.
Conf.Proc.C 830821V2 (1983) 267-268, 1983.
Inspire Record 194973 DOI 10.17182/hepdata.39517

None

2 data tables

No description provided.

No description provided.