De Leo, R.
Phenomenology-HEP
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Measurement of the spin dependent structure function g1(x) of the proton.

The Spin Muon (SMC) collaboration Adams, D. ; Adeva, B. ; Arik, E. ; et al.
Phys.Lett.B 329 (1994) 399-406, 1994.
Inspire Record 373036 DOI 10.17182/hepdata.48171

: We have measured the spin-dependent structure function $g_1~p$ of the proton in deep inelastic scattering of polarized muons off polarized protons, in the kinematic range $0.003<x<0.7$ and $1\,\mbox{GeV}~2<Q~2<60\,\mbox{GeV}~2$. Its first moment, $\int_0~1 g_1~p(x) dx $, is found to be $0.136 \pm 0.011\,(\mbox{stat.})\pm 0.011\,(\mbox{syst.})$ at $Q~2=10\,\mbox{GeV}~2$. This value is smaller than the prediction of the Ellis--Jaffe sum rule by two standard deviations, and is consistent with previous measurements. A combined analysis of all available proton, deuteron and neutron data confirms the Bjorken sum rule to within $10\%$ of the theoretical value.

3 data tables
Table 1

Results on the virtual photon proton asymmetry.

Table 2

Results on the spin structure function of the proton.

Table 3

Data for g1 at fixed Q**2 = 10 GeV (assuming no Q**2 dependence of A1).


THE DEPENDENCE OF CHARACTERISTICS OF pi+- MESONS PRODUCED IN pi- C INTERACTIONS AT 40-GeV/c ON TOTAL ENERGY IN THE CMS AND QCD OF SEMIHARD PROCESS

Baatar, Ts. ; Ivanovskaya, I.A. ; Serdamba, L. ; et al.
JINR-P1-88-469, 1988.
Inspire Record 267040 DOI 10.17182/hepdata.38869

None

3 data tables
Table 1

THE MULTIPLICITY OF CHARGED PIONS HAS BEEN FITTED BY THE FORMULA: MULT(PI+-)=CONST(Q=1)+CONST(Q=2)*EXP(+SLOPE*2*SQRT(LN(S))), WHERE S IS THE TOTAL ENERGY SQUERED OF THE SYSTEM PROJECTILE - PARTICIPATOR AND IS DEFINED AS 2*E(P=1)*(TARGET MASS), WHERE TARGET MASS HAS BEEN OBTAINED AS A SUM OF (E-PL) OVER SECONDARY PARTICLES.

Table 2

THE AVERAGE PT OF CHARGED PIONS HAS BEEN FITTED BY THE FORMULA: MEAN(N=PT)=CONST(Q=1)+CONST(Q=2)*EXP(SLOPE*SQRT(LN(S))), WHERE S IS THE TOTAL ENERGY SQUERED OF THE SYSTEM PROJECTILE - PARTICIPATOR AND IS DEFINED AS 2*E(P=1)*(TARGET MASS), WHERE TARGET MASS HAS BEEN OBTAINED AS A SUM OF (E-PL) OVER SECONDARY PARTICLES.

Table 3

THE AVERAGE PT**2 OF CHARGED PIONS HAS BEEN FITTED BY THE FORMULA: MEAN(N=PT**2)=CONST(Q=1)+CONST(Q=2)*EXP(SLOPE*SQRT(LN(S))), WHERE S IS THE TOTAL ENERGY SQUERED OF THE SYSTEM PROJECTILE - PARTICIPATOR AND IS DEFINED AS 2*E(P=1)*(TARGET MASS), WHERE TARGET MASS HAS BEEN OBTAINED AS A SUM OF (E-PL) OVER SECONDARY PARTICLES.


COMPARISON OF THE PARTICLE FLOW IN q anti-q g AND q anti-q gamma EVENTS IN e+ e- ANNIHILATION

The TPC/Two Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Avery, R.E. ; et al.
Phys.Rev.Lett. 57 (1986) 945, 1986.
Inspire Record 230224 DOI 10.17182/hepdata.38183

We compare the particle flow in the event plane of three-jet qq¯g (quark-antiquark-gluon) events with the particle flow in radiative annihilation events qq¯γ (quark-antiquark-photon) for similar kinematic configurations. In the angular region between quark and antiquark jet, we find a significant decrease in particle density for qq¯g as compared to qq¯γ. This effect is predicted in QCD as a result of destructive interference between soft-gluon radiation from quark, antiquark, and hard gluon.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Study of Longitudinal Distributions in the Fragmentation Regions, Using the Quark - Parton Model in $K^- p$ Interactions at 70-{GeV}/$c$

de Billy, L. ; Briand, H. ; Dumarchez, J. ; et al.
Nucl.Phys.B 191 (1981) 574-590, 1981.
Inspire Record 10816 DOI 10.17182/hepdata.34218

The study of π ± , π 0 , K 0 and Λ production in the fragmentation regions (| x |0.2) of K − p interactions at 70 GeV/ c shows that the x -dependence of each invariant cross section is well described by the power law (1−| x |) n suggested by the dimensional counting rule. Furthermore, pion production is found, both in K − and proton fragmentation regions, to be very similar to their production in ν( ν ) p interactions as expected from quark-parton models. The quark and diquark fragmentation functions D u π , D uu π and D ud π are extracted from our data.

1 data table
Table 1

No description provided.


Energy Dependence of Transverse Momentum Invariant Distribution of Pions and Neutral Kaons in $K^- p$ Interactions Between 14.3-{GeV}/$c$ and 70-{GeV}/$c$

Laffaille, J.M. ; Barloutaud, R. ; Louedec, C. ; et al.
Nucl.Phys.B 192 (1981) 18, 1981.
Inspire Record 156048 DOI 10.17182/hepdata.34202

The energy dependence of the transverse momentum invariant distribution of pions and neutral kaons is studied in K − p interactions between 14.3 and 70 GeV/ c . The large P T part of the distributions violates the Feynman scaling and, above P T ≃ 1.5 GeV/ c , appears to be reasonably described by hard scattering models. The variation of the average transverse momentum is also studied as a function of the c.m. reduced longitudinal momentum, and its behaviour is compared to the data obtained via the hadronic shower produced in lepton-hadron interactions.

2 data tables
Table 1

HERE K0 MEANS K0 OR AK0 I.E. K(NEUTRAL).

Table 2

No description provided.


Vector meson production and the kaon structure function

Chliapnikov, P.V. ; Knyazev, V.V. ; Likhoded, A.K. ; et al.
IFVE-80-122, 1980.
Inspire Record 155759 DOI 10.17182/hepdata.41612

None

3 data tables
Table 1

No description provided.

Table 2

FOR REACTION K+ P --> K0 ANYTHING K0S ARE PROMPT.

Table 3

No description provided.


Fluctuations in Large Angle $\pi^\pm p$ Elastic Scattering

Jenkins, K.A. ; Price, L.E. ; Klem, R. ; et al.
Phys.Rev.Lett. 40 (1978) 429, 1978.
Inspire Record 6210 DOI 10.17182/hepdata.76245

Large-angle π±p elastic-scattering cross sections, measured between 2 and 9 GeV/c in fine intervals of incident momentum and scattering angle, are used to search for cross-section fluctuations occurring for small changes in the center-of-mass energy as suggested by Ericson and Mayer-Kuckuck and by Frautschi. Significant fluctuations are observed.

144 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

More…

Analysis of Two Prong Events in anti-Proton-Proton Interactions at 5.7-GeV/c

Braun, Henri ; Gerber, J.-P. ; Maurer, G. ; et al.
Nucl.Phys.B 95 (1975) 481-502, 1975.
Inspire Record 2106 DOI 10.17182/hepdata.31929

A study of elastic scattering, one-pion production and annihilation reactions in p p interactions at 5.7 GeV/ c was carried out, from the two-prong events, obtained in the hydrogen bubble chamber exposed at CERN.

2 data tables
Table 1

NUMBER OF EVENTS FOR -T<0.03 GEV**2 CALCULATED BY EXTRAPOLATION.

Table 2

No description provided.