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Transverse spin effects in hadron-pair production from semi-inclusive deep inelastic scattering

The COMPASS collaboration Adolph, C. ; Alekseev, M.G. ; Alexakhin, V.Yu. ; et al.

Phys.Lett.B 713 (2012) 10-16, 2012.

Inspire Record 1090927 DOI 10.17182/hepdata.58899

First measurements of azimuthal asymmetries in hadron-pair production in deep-inelastic scattering of muons on transversely polarised ^6LiD (deuteron) and NH_3 (proton) targets are presented. The data were taken in the years 2002-2004 and 2007 with the COMPASS spectrometer using a muon beam of 160 GeV/c at the CERN SPS. The asymmetries provide access to the transversity distribution functions, without involving the Collins effect as in single hadron production. The sizeable asymmetries measured on the NH_ target indicate non-vanishing u-quark transversity and two-hadron interference fragmentation functions. The small asymmetries measured on the ^6LiD target can be interpreted as indication for a cancellation of u- and d-quark transversities.

6 data tables

Table 1

The measured transverse asymmetry from the proton target as a function of the variable X. Mean values are also given for the variables Q**2[GeV^2], Y, Z, M[GeV], M**2[GeV^2], SIN(THETA), COS(THETA), COS(THETA)**2 and the transverse spin transfer coefficient DNN.

Table 2

The measured transverse asymmetry from the proton target as a function of the variable Z. Mean values are also given for the variables Q**2[GeV^2], Y, X, M[GeV], M**2[GeV^2], SIN(THETA), COS(THETA), COS(THETA)**2 and the transverse spin transfer coefficient DNN.

Table 3

The measured transverse asymmetry from the proton target as a function of the variable M. Mean values are also given for the variables Q**2[GeV^2], Y, Z, X, M**2[GeV^2], SIN(THETA), COS(THETA), COS(THETA)**2 and the transverse spin transfer coefficient DNN Note that the data in the last bin (>1.5) does not contribute to the X and Z distributions.

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rivet Analysis
Inclusive production of charged pions in p p collisions at 158-GeV/c beam momentum.

The NA49 collaboration Alt, C. ; Anticic, T. ; Baatar, B. ; et al.

Eur.Phys.J.C 45 (2006) 343-381, 2006.

Inspire Record 694016 DOI 10.17182/hepdata.43114

New results on the production of charged pions in p+p interactions are presented. The data come from a sample of 4.8 million inelastic events obtained with the NA49 detector at the CERN SPS at 158 GeV/c beam momentum. Pions are identified by energy loss measurement in a large TPC tracking system which covers a major fraction of the production phase space. Inclusive invariant cross sections are given on a grid of nearly 300 bins per charge over intervals from 0 to 2 GeV/c in transverse momentum and from 0 to 0.85 in Feynman x. The results are compared to existing data in overlapping energy ranges.

26 data tables

Table 1

Double differential cross sections for PI+ and PI- in P P interactions at 158 GeV.

Table 2

Double differential cross sections for PI+ and PI- in P P interactions at 158 GeV.

Table 3

Double differential cross sections for PI+ and PI- in P P interactions at 158 GeV.

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Rescattering probed by the emission of slow target associated particles in high-energy heavy ion interactions

The EMU01 collaboration Adamovich, M.I ; Aggarwal, M.M ; Alexandrov, Y.A ; et al.

Phys.Lett.B 363 (1995) 230-236, 1995.

Inspire Record 406952 DOI 10.17182/hepdata.28438

In this letter the distribution of slow target associated particles emitted in Au + Emulsion interactions at 11.6 A GeV/ c is studied. The three models RQMD, FRITIOF and VENUS are used for comparisons and especially their treatment of rescattering is investigated.

6 data tables

Table 1

No description provided.

Table 2

PROJECTILE ASSOCIATED HE-FRAGMENTS.

Table 3

No description provided.

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Central Collisions of 800-{GeV} Protons With Ag / Br Nuclei in Nuclear Emulsion

The BATON ROUGE-KRAKOW-MOSCOW-TASHKENT collaboration Abduzhamilov, A. ; Barbier, L.M. ; Chernova, L.P. ; et al.

Phys.Rev.D 39 (1989) 86-91, 1989.

Inspire Record 280844 DOI 10.17182/hepdata.3813

Central collisions of 800-GeV protons with the heavy components of nuclear emulsion, Ag107 and Br80, have been investigated to determine the characteristics of small-impact-parameter collisions and, by comparison with the analysis of inclusive proton-emulsion inelastic interactions and inelastic proton-nucleon collisions, to study the dependence of the interaction process on the mean number of intranuclear collisions 〈ν〉. The data are also compared with the results obtained in proton-emulsion collisions, both central and inclusive, at 200 GeV. The variations in the secondary-particle multiplicities and the normalized pseudorapidity density correlate with 〈ν〉 and demonstrate that proton-nucleus interactions, both central and inclusive, can be described adequately by the incoherent superposition of proton-nucleon collisions.

5 data tables

Table 1

NUCLEUS IS AVERAGE NUCLEUS OF EMULSION.

Table 2

NUCLEUS IS AVERAGE NUCLEUS OF EMULSION.

Table 3

NUCLEUS IS AVERAGE NUCLEUS OF EMULSION.

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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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Charged Particle Multiplicity and Angular Distributions in Proton Emulsion Interactions at 800-{GeV}

The BATON ROUGE-CRACOW-MOSCOW-TASHKENT collaboration Abduzhamilov, A. ; Barbier, L. ; Chernova, L.P. ; et al.

Phys.Rev.D 35 (1987) 3537-3540, 1987.

Inspire Record 254225 DOI 10.17182/hepdata.3930

The interaction of 800-GeV protons in nuclear emulsion has been investigated. The multiplicities and angular distributions of charged particles emitted by both the projectile and the target nucleus have been measured for 1718 inelastic events and are compared with the data obtained in proton-emulsion collisions at 67, 200, and 400 GeV. The target excitation is found to be independent of energy while the production of secondary particles continues to increase with incident proton energy.

3 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

OBSERVATION OF ANTI-D MESONS IN N C INTERACTIONS AT 40-GEV/C - 70-GEV/C.

The BIS-2 collaboration Aleev, A.N. ; Arefev, V.A. ; Balandin, V.P. ; et al.

Czech.J.Phys.B 36 (1986) 1303-1310, 1986.

Inspire Record 222567 DOI 10.17182/hepdata.39496

We have observed the production of$\bar D^0 $ andD− mesons in neutron carbon interactions at 40–70 GeV/c. The experiment was performed with the spectrometer BIS-2 located in the neutron beam 4N of the Serpukhov accelerator.

4 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

CORRECTED FOR ACCEPTANCE. AUTHORS NAMED THIS SPECTRUM 'INVARIANT'.

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Observation and Study of a Narrow State in a $\Sigma^-$ (1385) $K^+$ System

The Berlin-Budapest-Dubna-Moscow-Prague-Sofiya-Tbilisi collaboration Aleev, A.N. ; Arefev, V.A. ; Balandin, V.P. ; et al.

Z.Phys.C 25 (1984) 205, 1984.

Inspire Record 201523 DOI 10.17182/hepdata.39601

New data on the observation and study of a narrow resonance decaying intoΣ−(1,385)K+ have been obtained. The mass of the resonance is (1,956−6+8) MeV/c2, and its width is (27±15) MeV/c2. The resonance is produced in the diffraction dissociation of neutrons on quasi-free nucleons of carbon nuclei. The slope parameter of the differential cross section inPT2 is (9.9±3.0) (GeV/c)−2. The cross section times the branching ratio is (0.22±0.04) μb per nucleon. The resonance has one of the natural spinparities: 5/2+, 7/2− and so on.

5 data tables

Table 1

YN IS IN ARBITRARY UNITS.

Table 2

Table 3

ARBITRARY UNITS FOR YN.