Alekseev, I.G.
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A measurement of the spin asymmetry and determination of the structure function g(1) in deep inelastic muon proton scattering.

The European Muon collaboration Ashman, J. ; Badelek, B. ; Baum, Guenter ; et al.
Phys.Lett.B 206 (1988) 364, 1988.
Inspire Record 252744 DOI 10.17182/hepdata.29952

The spin asymmetry in deep inelastic scattering of longitudinally polarised muons by longitudinally polarised protons has been measured over a large x range (0.01< x <0.7). The spin-dependent structure function g 1 ( x ) for the proton has been determined and its integral over x found to be 0.114±0.012±0.026, in disagreement with the Ellis-Jaffe sum rule. Assuming the validity of the Bjorken sum rule, this result implies a significant negative value for the integral of g 1 for the neutron. These values for the integrals of g 1 lead to the conclusion that the total quark spin constitutes a rather small fraction of the spin of the nucleon.

1 data table
Table 1

THE AVERAGE VALUES OF Q**2 IN EACH X-BIN ARE AS FOLLOWS: X=0.015,Q2=3.5: X=0.025,Q2=4.5: X=0.035,Q2=6.0: X=0.050,Q2=8.0: X=0.078,Q2=10.3: X=0.124,Q2=12.9: X=0.175,Q2=15.2: X=0.248,Q2=18.0: X=0.344,Q2=22.5: X=0.466,Q2=29.5.


Exclusive $\rho^0$ and $\phi$ Production in Deep Inelastic Muon Scattering

The European Muon collaboration Ashman, J. ; Badelek, B. ; Baum, G. ; et al.
Z.Phys.C 39 (1988) 169, 1988.
Inspire Record 252743 DOI 10.17182/hepdata.15619

Data are presented on exclusive ρ0 and ϕ production in deep inelastic muon scattering from a target consisting mainly of nitrogen. The ratio of the total cross sections for ρ0 and ϕ production is found to be 9∶(1.6±0.4) at 〈Q2〉=7.5 GeV2, consistent with theSU(3) prediction of 9∶2. Thet dependence for exclusive ρ0 production is found to become shallover asQ2 increases and, for largeQ2, thet dependence is typical of that for a hard scattering process. Furthermore, the ratio of the cross sections for coherent: incoherent production from nitrogen is found to decrease rapidly withQ2. Such behaviour indicates that even for exclusive vector meson production the virtual photon behaves predominantly as an electromagnetic probe.

6 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Experimental Study of $B \bar{B}$ Production in $\pi^-$ U Interactions at 320-{GeV} Energy

The WA78 collaboration Catanesi, M.G. ; Muciaccia, M.T. ; Natali, S. ; et al.
Phys.Lett.B 202 (1988) 453-457, 1988.
Inspire Record 252002 DOI 10.17182/hepdata.49588

A sample of 29 gu + υ + 35 υ − υ − coming from B B decay have been observed in π -U interactions at 320 GeV energy. The experimental distributions and the total cross section are found to be in good agreement with QCD predictions. The effect of B 0 B 0 mixing is discussed.

2 data tables
Table 1

BEAUTY INCLUSIVE SPECTRA WAS ASSUMED MN FORM : E*D(SIG)/D(X)/D(PT**2) = EXP(-0.9*PT**2)*(1-ABS(X))**A. THE BEST FIT FOR A IS A = 2.5.

Table 2

No description provided.


Production of anti-D0 and D- Mesons in Neutron - Carbon Interactions at 40-GeV to 70-GeV

The BIS-2 collaboration Aleev, A.N. ; Arefev, V.A. ; Balandin, V.P. ; et al.
Z.Phys.C 37 (1988) 243, 1988.
Inspire Record 248611 DOI 10.17182/hepdata.9960

The production of\(\bar D\) mesons in neutroncarbon interactions at 40–70 GeV/c has been investigated. The\(\bar D\) mesons were detected via the hadronic decay modes\(\bar D^0\to K^{* + } (892)\pi ^ -\) andD−→K*+(892)π−π−. In the kinematical regionxF>0.5 andpT<1 GeV/c the following inclusive cross sections were measured:\(\sigma _{\bar D^0 }= (28 \pm 14)\mu b\) and\(\sigma _{D^ -}= (28 \pm 13)\mu b\) per carbon nucleus. The invariant longitudinal momentum spectra can be described by (1−x)N with\(N_{\bar D^0 }= 1.1 \pm 0.5 \pm 0.4\) and\(N_{D^ -}= 0.8 \pm 0.4 \pm 0.4\) The transverse momentum spectra were parametrized by exp (−BpT2) with\(B_{\bar D^0 }= (1.2_{ - 0.9}^{ + 1.1} )({{GeV} \mathord{\left/ {\vphantom {{GeV} c}} \right. \kern-\nulldelimiterspace} c})^{ - 2} \) and\(B_{D^ -}= (1.8_{ - 1.0}^{ + 1.3} )({{GeV} \mathord{\left/ {\vphantom {{GeV} c}} \right. \kern-\nulldelimiterspace} c})^{ - 2} \).

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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OBSERVATION OF INVERSE ELECTROPRODUCTION OF PIONS ON C-12 NUCLEUS AT 164-MeV PION ENERGY AND DETERMINATION OF F1(v) NUCLEON FORM-FACTOR

Alekseev, G.D. ; Blokhintseva, T.D. ; Karpukhin, V.V. ; et al.
Sov.J.Nucl.Phys. 46 (1987) 801, 1987.
Inspire Record 247868 DOI 10.17182/hepdata.38865

None

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


A-dependence of the Charm Production Cross-section in 320-{GeV}/$c \pi^-$ Interactions

The WA78 collaboration Cobbaert, H. ; Roosen, R. ; Catanesi, M.G. ; et al.
Phys.Lett.B 191 (1987) 456-461, 1987.
Inspire Record 236083 DOI 10.17182/hepdata.30162

Using a 320 GeV c π − beam incident on three different target materials Al, Fe, and U, the A -dependence of charm production is studied by measuring the yield of prompt single muons. Parametrizing the charm cross section as σ cc ( π − A) = σ 0 Aα the measured α values are α ( μ + ) = 0.76 ± 0.08 and α ( μ − ) = 0.83 ± 0.06.

2 data tables
Table 1

No description provided.

Table 2

Numbers of events per 10**6 incident PI-.


The Production of Beauty Particles in $\pi^-$ U Interactions at 320-{GeV} Energy

The WA78 collaboration Catanesi, M.G. ; Muciaccia, M.T. ; Natali, S. ; et al.
Phys.Lett.B 187 (1987) 431-436, 1987.
Inspire Record 235069 DOI 10.17182/hepdata.6522

B B production in π − -uranium interactions has been observed at 320 GeV beam energy looking at events with three muons in the final state. The cross section is found to be σ B B = 4.5±1.4±1.4 nb per nucleon (for a linear A -dependence) or σ B B = 17.6±5.5±5.5 nb per nucleon (assuming A 0.75 dependence). An estimate of x F distribution is given.

3 data tables
Table 1

BEAUTY INCLUSIVE SPECTRA WAS ASSUMED TO BE E*D(SIG)/D(X)/D(PT**2) = EXP(-0.9*PT**2)*(1-ABS(X))**A. THE BEST FIT FOR A IS A = 2.5.

Table 2

ASSUME A**.75 DEPENDENCE.

Table 3

No description provided.


A-dependence of Polarization of $\Lambda^0$ Produced Inclusively in Neutron - Nucleus Interactions

The BIS-2 collaboration Aleev, A.N. ; Arefev, V.A. ; Balandin, V.P. ; et al.
Z.Phys.C 36 (1987) 27, 1987.
Inspire Record 237043 DOI 10.17182/hepdata.39599

TheA-dependence of the polarization ofΛ0,s produced inclusively in neutron-nucleus interactions at a mean neutron momentum of about 40 GeV/c has been measured in an experiment performed using the BIS-2 spectrometer at the Serpukhov accelerator. Carbon, Aluminium and Copper targets were used. TheΛ0,s were produced in the kinematical region of 0.6<pT<1.3 GeV/c and 0.2<xF<0.9. Describing the polarization of theΛ0,s by ℘=a·A a value of (−0.15+0.07/−0.60) was obtained by a fit to our data.

2 data tables
Table 1

POLARIZATION IS DESCRIBED BY A POWER LOW: POL = C*A**B, WHERE C = -1.1, +0.4, -0.3 , A- ATOMIC NUMBER AND B = -0.15, +0.07, -0.6.


A-dependence of the Production Cross-section of $\Lambda(c$)+ Charmed Baryons in Neutron - Nucleus Interactions

The BIS-2 collaboration Aleev, A.N. ; Arefev, V.A. ; Balandin, V.P. ; et al.
Sov.J.Nucl.Phys. 46 (1987) 657, 1987.
Inspire Record 235393 DOI 10.17182/hepdata.39661

None

1 data table
Table 1

No description provided.


Inclusive Production of Hyperons and Anti-hyperons in $N$ C Collisions at an Energy of About 40-{GeV} (In Russian)

The BIS-2 collaboration Aleev, A.N. ; Arefev, V.A. ; Balandin, V.P. ; et al.
Yad.Fiz. 44 (1986) 661-670, 1986.
Inspire Record 239304 DOI 10.17182/hepdata.17456

None

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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