Akerlof, C.
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An investigation of the spin structure of the proton in deep inelastic scattering of polarized muons on polarized protons.

The European Muon collaboration Ashman, J. ; Badelek, B. ; Baum, Guenter ; et al.
Nucl.Phys.B 328 (1989) 1, 1989.
Inspire Record 280143 DOI 10.17182/hepdata.49587

The spin asymmetry in deep inelastic scattering of longitudinally polarised muons by longitudinally polarised protons has been measured in the range 0.01<×<0.7. The spin dependent structure function g 1 ( x ) for the proton has been determined and, combining the data with earlier SLAC measurements, its integral over x found to be 0.126±0.010(stat.)±0.015(syst.), in disagreement with the Ellis-Jaffe sum rule. Assuming the validity of the Biorken sum rule, this result implies a significant negative value for the integral of g 1 for the neutron. These integrals lead to the conclusion, in the naïve quark parton model, that the total quark spin constitutes a rather small fraction of the spin of the nucleon. Results are also presented on the asymmetries in inclusive hadron production which are consistent with the above picture.

7 data tables
Table 1

THE MEAN Q**2 FOR EACH OF THE 10 VALUES OF X BELOW ARE 3.5,4.5,6.0, 8.010.3,12.9,15.2,18.0,22.5,29.5.

Table 2

No description provided.

Table 3

No description provided.

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rivet Analysis
Observation of $\Delta^{++}$ (1232) Production in $e^+ e^-$ Annihilations Around 10-{GeV}

The ARGUS collaboration Albrecht, H. ; Glaser, R. ; Harder, G. ; et al.
Phys.Lett.B 230 (1989) 169-174, 1989.
Inspire Record 278932 DOI 10.17182/hepdata.29767

We report on the first observation of Δ(1232) ++ and Δ(1232)++¯ baryons in e + e − annihilation at energies around 10 GeV, using the ARGUS detector at DORIS II. The sum of the rates of Δ ++ and Δ++¯ per hadronic event in the continuum is measured to be 0.040±0.008±0.006, and the rate in direct ϒ(1S) decays is 0.124±0.016±0.015. The momentum spectrum of Δ ++ baryons in direct ϒ(1S) decays has been measured.

2 data tables
Table 1

Production on the UPSI(1S) resonance.

Table 2

No description provided.


Observation of Centrally Produced $\theta$ / F2 (1720) in the Reaction $p p \to p$(f) ($K \bar{K}$) $p(s$) at 300-{GeV}/$c$

The WA76 collaboration Armstrong, T.A. ; Benayoun, Maurice ; Beusch, W. ; et al.
Phys.Lett.B 227 (1989) 186-190, 1989.
Inspire Record 279351 DOI 10.17182/hepdata.29801

The K + K − and K S 0 K S 0 systems centrally produced in the reaction pp→p f K K p s have been studied at 300 GeV/ c incident momentum. Both the K + K − and the K S 0 K S 0 mass spectra show large resonant production. For the first time in hadron collisions, clear evidence is found for the θ f 2 (1720) with parameters m =1713±10 MeV, Γ =181±30 MeV for the K + K − decay mode and m =1706±10 MeV, Γ =104±30 MeV for the K S 0 K S 0 decay mode. A spin analysis of the K + K − spectrum shows that for the θ f 2 (1720) J P =2 + is strongly favoured while 0 + and 1 − are excluded.

2 data tables
Table 1

Density matrix elements contributing in the fits of angular distributions in the F2PRIME(1525) region.

Table 2

Density matrix elements contributing in the fits of angular distributions in the F2(1720) region.


PRODUCTION OF BACKWARD PROTONS WITH MOMENTA 0.2-GeV/c TO 0.5-GeV/c IN LAB SYSTEM WHICH ARE GENERATED IN pi- A INTERACTIONS AT 40-GeV/c

The RISK collaboration Bannikov, A.V. ; Bohm, J. ; Vertogradov, L.S. ; et al.
JINR-P1-89-308, 1989.
Inspire Record 281737 DOI 10.17182/hepdata.38756

None

8 data tables
Table 1

No description provided.

Table 2

THE EVENTS WITH BACKWARD PROTONS.

Table 3

THE EVENTS WITHOUT BACKWARD PROTONS.

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EXCLUSIVE MEASUREMENTS OF LIGHT FRAGMENT PRODUCTION AT FORWARD ANGLES IN Ne - Pb AND Ne - NaF COLLISIONS AT E/A = 400-MeV AND 800-MeV

Bastid, N. ; Alard, J.P. ; Arnold, J. ; et al.
Nucl.Phys.A 506 (1990) 637-654, 1990.
Inspire Record 25478 DOI 10.17182/hepdata.36887

Emission of light fragments at small angles is studied in relativistic heavy ion collisions using the Diogene plastic wall for both symmetrical and non-symmetrical target-projectile systems with 400 MeV per nucleon and 800 MeV per nucleon incident neon nuclei. Efficiency of multiplicity measurements in the small angle range for the selection of central or peripheral collisions is confirmed for asymmetric systems. Differential production cross sections of Z = 1 fragments show evidence for the existence of two emitting sources. The apparent temperature of each source is obtained from comparison with a thermodynamical model.

2 data tables
Table 1

THE NUCLEUS IS NAF. CHARGED PARTICLES IN THE CENTRAL DRIFT CHAMBER OF THE DIOGENE DETECTOR.

Table 2

THE NUCLEUS IS NAF. CHARGED PARTICLES IN THE CENTRAL DRIFT CHAMBER OF THE DIOGENE DETECTOR. THE EVENT SELECTION:A HEAVY FRAGMENT(Z>=6) IS REGISTRED IN THE PLASTIC WALL OF THE DIOGENE.


$\Sigma(c$)++ and $\Sigma(c$)0 Production From $e^+ e^-$ Annihilation in the $\Upsilon$ Energy Region

The CLEO collaboration Bowcock, T.J.V. ; Kinoshita, K. ; Pipkin, F.M. ; et al.
Phys.Rev.Lett. 62 (1989) 1240, 1989.
Inspire Record 25467 DOI 10.17182/hepdata.47269

We have observed Σc++ and Σc0 baryons in nonresonant e+e− interactions through their decays to Λc+π± using the CLEO detector. The mass difference M(Σc++)-M(Λc+) is measured to be 167.8±0.4±0.3 MeV; for M(Σc0)-M(Λc+) we find 167.9±0.5±0.3 MeV. Σc decay accounts for (18±3±5)% of Λc+ production.

2 data tables
Table 1

The cross section ratio is multiplied by a factor of 1.5 to account for theunobserved SIGMA/C(2455)+.

Table 2

No description provided.


Precision Measurements of the Anti-proton - Proton Elastic Scattering Cross-section at 90-degrees in the Incident Momentum Range Between 3.5-{GeV}/$c$ and 5.7-{GeV}/$c$

The R704 collaboration Baglin, C. ; Baird, S. ; Bassompierre, G. ; et al.
Phys.Lett.B 225 (1989) 296-300, 1989.
Inspire Record 278760 DOI 10.17182/hepdata.29802

The high antiproton-proton luminosity obtained by using a target system consisting of a hydrogen gas-jet crossing a coasting beam of cooled antiproton circulating in one of the rings of CERN's ISR provides the possibility to measure low cross section reactions with very high precision. We present measurements of the antiproton-proton elastic cross section at 90° CM at incident momenta between 3.5 GeV/ c and 5.7 GeV/ c . The precision of these measurements is much higher than previously reported results. The data show that the cross section of this reaction decreases faster than s −12 over this momentum range.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


NUCLEAR REACTIONS OF TANTALUM WITH 3.65-A/GeV C-12 IONS AND 3.65-GeV PROTONS

Kozma, P. ; Damdinsuren, C. ; Chultem, D. ; et al.
J.Phys.G 17 (1991) 675-690, 1991.
Inspire Record 281499 DOI 10.17182/hepdata.38565

The cross sections of a number of target residues formed in the reactions of 3.65 A GeV 12C ions and 3.65 GeV protons with tantalum have been measured. The measurements have been done by direct counting of irradiated targets with a Ge(Li) gamma-ray spectrometer. Charge dispersions and mass-yield distributions were deduced from these data. The results are discussed in terms of the basic concepts of high-energy nuclear physics. They are also compared with intranuclear cascade and abrasion-ablation model calculations.

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Production of $\Lambda$ Hyperons and $K^0(s$) Mesons in Annihilation of Anti-protons in $^{4}$He Nuclei at 600-{MeV}/$c$

Batusov, Yu.A. ; Bunyatov, S.A. ; Falomkin, I.V. ; et al.
Sov.J.Nucl.Phys. 50 (1989) 945-948, 1989.
Inspire Record 280132 DOI 10.17182/hepdata.39439

None

4 data tables
Table 1

43 EVENTS WITH LAMBDA, 54 EVENTS WITH KS.

Table 2

43 EVENTS WITH LAMBDA, 54 EVENTS WITH KS.

Table 3

43 EVENTS WITH LAMBDA, 54 EVENTS WITH KS. D(N)/D(P) WAS FITTED BY P**2*EXP(-SLOPE*EKIN).

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Vector Meson Production in $\pi^- p$ Interactions at 360-{GeV}/$c$

The LEBC-EHS collaboration Aguilar-Benitez, M. ; Bailly, J.L. ; Batalov, A.A. ; et al.
Z.Phys.C 44 (1989) 531, 1989.
Inspire Record 278763 DOI 10.17182/hepdata.15359

The inclusive production of vector mesons (charged ρ(770), ω(783), ϕ(1020) and neutralK*(892)) in π−p interactions at 360 GeV/c is studied. The data are based on 160 000 reconstructed events recorded in the NA 27 Experiment using the LEBC-EHS facility at CERN. The production cross sections in the forward hemisphere in c.m.s. and the longitudinal momentum distributions are determined. The results are compared with data obtained at lower energies.

17 data tables
Table 1

No description provided.

Table 2

Upper limits of cross sections.

Table 3

Cross sections extrapolated to x > 0.

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