HEPData Search

Showing 10 of 60 results

A Re-Evaluation of the nuclear Structure Function Ratios for D, He, Li, C and Ca

The New Muon collaboration Amaudruz, P. ; Arneodo, M. ; Arvidson, A. ; et al.

Nucl.Phys.B 441 (1995) 3-11, 1995.

Inspire Record 393377 DOI 10.17182/hepdata.32848

We present a re-evaluation of the structure function ratios F2(He)/F2(D), F2(C)/F2(D) and F2(Ca)/F2(D) measured in deep inelastic muon-nucleus scattering at an incident muon momentum of 200 GeV. We also present the ratios F2(C)/F2(Li), F2(Ca)/F2(Li) and F2(Ca)/F2(C) measured at 90 GeV. The results are based on data already published by NMC; the main difference in the analysis is a correction for the masses of the deuterium targets and an improvement in the radiative corrections. The kinematic range covered is 0.0035 < x < 0.65, 0.5 < Q^2 <90 GeV^2 for the He/D, C/D and Ca/D data and 0.0085 < x < 0.6, 0.84 < Q^2 < 17 GeV^2 for the Li/C/Ca ones.

6 data tables

Table 1

Additional normalization uncertainty of 0.4 pct not included.

Table 2

Additional normalization uncertainty of 0.4 pct not included.

Table 3

Additional normalization uncertainty of 0.4 pct not included.

More…

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.

BOUND STATES BETWEEN PROTONS AND MAGNETIC POLES: INFLUENCE ON THE RUBAKOV EFFECT

Masperi, L. ; Mazzitelli, F.D. ;

Lett.Nuovo Cim. 43 (1985) 123, 1985.

Inspire Record 15833 DOI 10.17182/hepdata.37590

Taking into account the structure of the proton in a very simple way, we find the energy levels and the wave functions for the bound states of a proton in the field of an Abelian magnetic pole, confirming the enhancement of the Rubakov effect.

1 data table

Table 1

No description provided.

Hyperon Production in $e^+ e^-$ Interactions in the $\Upsilon$ Region

The CLEO collaboration Alam, M.S. ; Csorna, S.E. ; Garren, L. ; et al.

Phys.Rev.Lett. 53 (1984) 24, 1984.

Inspire Record 200712 DOI 10.17182/hepdata.20410

We report measurements from the CLEO detector of the rate of Ξ and Λ production in e+e− interactions in the upsilon region. Hyperon production from the decay of the ϒ(1s) is compared with continuum e+e− data. The ratio of the production rates of Λ (and Λ―) to K0 (and K―0) on the ϒ(1s) is 0.21 ± 0.03, much larger than in the continuum, 0.07 ± 0.01. The ratios of the production rates of the Ξ and Λ are comparable, 0.10±0.02 [ϒ(1S)] and 0.07 ± 0.02 (continuum). We discuss some implications of the data for gluon and quark fragmentation models.

2 data tables

Table 1

CONTINUUM IS ECM 10.38 TO 10.64 GEV.

Table 2

No description provided.

ESTIMATE OF THE AVERAGE MULTIPLICITY OF RELATIVISTIC PROTONS PRODUCED IN MULTI - NUCLEON AND pi- C-12 INTERACTIONS

Grishin, V.G. ; Kanarek, T. ; Simic, L. ;

Sov.J.Nucl.Phys. 36 (1982) 248, 1982.

Inspire Record 168966 DOI 10.17182/hepdata.39146

None

12 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

More…

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.