Alpgard, K.
DSIG/DPT
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phi meson production from p anti-p collisions at s**(1/2) = 1.8-TeV

The E735 collaboration Alexopoulos, T. ; Allen, C. ; Anderson, E.W. ; et al.
Z.Phys.C 67 (1995) 411-416, 1995.
Inspire Record 405368 DOI 10.17182/hepdata.14115

Fermilab experiment E735 located at the CO intersection region of the\(\sqrt s= 1.8\) TeV\(p\bar p\) collider analysed over 900 Φ→K+K− events. Measured were the transverse momentum spectrum, the correlation between the average transverse momentum and the charged particle multiphcityNc, as well as the probability of Φ production per charged track,NΦ/Nc, versusNc. We have also made an estinate of the total inclusive cross section for Φ mesons,\(\sigma (p\bar p \to \phi X) = 7.3 \pm 2.2 mb\).

3 data tables
Table 1

Corrected phi meson transverse momentum distribution at rapidity = 0.

Table 2

Total inclusive cross section.

Table 3

Ratio of phi to rho0 production in high and low charged particle multiplicity events.


Measurement of inclusive electron cross-section in gamma gamma collisions at TRISTAN

The TOPAZ collaboration Iwasaki, M. ; Enomoto, R. ; Hayashii, H. ; et al.
Phys.Lett.B 341 (1994) 99-108, 1994.
Inspire Record 378075 DOI 10.17182/hepdata.43778

We have studied open charm production in $\gamma \gamma$ collisions with the TOPAZ detector at the TRISTAN $e~{+}e~{-}$ collider. In this study, charm quarks were identified by electrons (and positrons) from semi-leptonic decays of charmed hadrons. The data corresponded to an integrated luminosity of 95.3 pb$~{-1}$ at a center-of-mass energy of 58 GeV. The results are presented as the cross sections of inclusive electron production in $\gamma \gamma$ collisions with an anti-tag condition, as well as the subprocess cross sections, which correspond to resolved-photon processes. The latter were measured by using a sub-sample with remnant jets. A comparison with various theoretical predictions based on direct and resolved-photon processes showed that our data prefer that with relatively large gluon contents in a photon at small $x (x \le 0.1)$, with the next-to-leading order correction, and with a charm-quark mass of 1.3 GeV.

2 data tables
Table 1

The description of events with anti-tag, remnant-jet-tag, and no-tag are presnted in text.


K0 (anti-K0) production in two photon processes at TRISTAN

The TOPAZ collaboration Enomoto, R. ; Abe, K. ; Abe, T. ; et al.
Phys.Lett.B 341 (1994) 238-244, 1994.
Inspire Record 377805 DOI 10.17182/hepdata.38385

We have carried out an inclusive measurement of $K~0(\overline{K~0})$ production in two-photon processes at TRISTAN. The mean $\sqrt{s}$ was 58 GeV and the integrated luminosity was 199 pb$~{-1}$. High-statistics $K_s$ samples were obtained under such conditions as no-, anti-electron, and remnant-jet tags. The remnant-jet tag, in particular, allowed us, for the first time, to measure the cross sections separately for the resolved-photon and direct processes.

6 data tables
Table 1

No tag data.

Table 2

Anti-electron tag data.

Table 3

Remnant-jet tag with VDM subtraction data.

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Production of K0 and Lambda in hadronic Z decays

The ALEPH collaboration Buskulic, D. ; Casper, D. ; De Bonis, I. ; et al.
Z.Phys.C 64 (1994) 361-374, 1994.
Inspire Record 375060 DOI 10.17182/hepdata.48239

Measurements of the inclusive cross-sections forK0 and Λ production in hadronic decays of the Z are presented together with measurements of two-particle correlations within pairs of Λ andK0. The results are compared with predictions from the hadronization models Jetset, based on string fragmentation, and Herwig, based on cluster decays. TheK0 spectrum is found to be harder than predicted by both models, while the Λ spectrum is softer than predicted. The correlation measurements are all reproduced well by Jetset, while Herwig misses some of the qualitative features and overestimates the size of the\(\Lambda \bar \Lambda \) correlation. Finally, the possibility of Bose-Einstein correlation in theKS0KS0 system is discussed.

7 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Measurement of the D*+- cross-section using a soft pion analysis in two photon processes

The TOPAZ collaboration Enomoto, R. ; Abe, K. ; Abe, T. ; et al.
Phys.Lett.B 328 (1994) 535-546, 1994.
Inspire Record 372139 DOI 10.17182/hepdata.38387

The differential cross section of $d\sigma(e~+e~-\rightarrow e~+e~-D~{*\pm}X)/dP_T$ was measured using a soft-pion analysis of $D~{*\pm}\rightarrow \pi_s~\pm D~0(\overline{D~0})$ at TRISTAN. The average $\sqrt{s}$ was 58.1 GeV and the integrated luminosity used in this analysis was 198 pb$~{-1}$, respectively.

4 data tables
Table 1

Soft pion cross section.

Table 2

D*+- cross section from the soft-pion analysis.

Table 3

Previous `full reconstruction' measurement from Enomoto et al. (to be published).

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Mass dependence of pi0 production in heavy ion collisions at 1-A/GeV

Schwalb, O. ; Pfeiffer, M. ; Berg, F.-D. ; et al.
Phys.Lett.B 321 (1994) 20-25, 1994.
Inspire Record 376130 DOI 10.17182/hepdata.28781

The production of neutral pions has been studied in the reactions 40 Ar + nat Ca , 86 Kr + nat Zr and 197 Au + 197 Au at 1 A GeV. For high energy pions emitted from the heavier systems a steeper than linear rise of the pion multiplicity with the centrality of the reaction is observed, indicating a pion production process other than binary nucleon-nucleon collisions. At low transverse momenta an enhancement of the π 0 -multiplicity increasing with the mass of the collision system is found. Systematic discrepancies between the experimental results and recent BUU, QMD and Cascade calculations are discussed.

6 data tables
Table 1

No description provided.

Table 2

RESULTS OF AN EXTRAPOLATION TO THE FULL SOLID ANGLE TAKING THE EXPERIMENTALTEMPERATURES INTO ACCOUNT.

Table 3

No description provided.

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Measurement of the inclusive jet cross-section in photon-photon interactions at TRISTAN

The AMY collaboration Kim, B.J. ; Nozaki, T. ; Bodek, A. ; et al.
Phys.Lett.B 325 (1994) 248-256, 1994.
Inspire Record 361660 DOI 10.17182/hepdata.38388

We present cross section measurements for inclusive jet production in almost-real photon-photon interactions at TRISTAN using the AMY detector. The results are compared with leading-order QCD calculations for different parameterizations of the parton density in the photon.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


Measurement of the D*+- cross-section in a two photon process

The TOPAZ collaboration Enomoto, R. ; Iwasaki, M. ; Muramatsu, K. ; et al.
Phys.Rev.D 50 (1994) 1879-1883, 1994.
Inspire Record 357776 DOI 10.17182/hepdata.38389

We have measured the inclusive $D~{*\pm}$ production cross section in a two-photon collision at the TRISTAN $e~+e~-$ collider. The mean $\sqrt{s}$ of the collider was 57.16 GeV and the integrated luminosity was 150 $pb~{-1}$. The differential cross section ($d\sigma(D~{*\pm})/dP_T$) was obtained in the $P_T$ range between 1.6 and 6.6 GeV and compared with theoretical predictions, such as those involving direct and resolved photon processes.

2 data tables
Table 1

Numerical values supplied by R. Enomoto.

Table 2

No description provided.


Measurement of the inclusive cross-section of jets in gamma gamma interactions at TRISTAN

The TOPAZ collaboration Hayashii, H. ; Miyamoto, A. ; Iwasaki, M. ; et al.
Phys.Lett.B 314 (1993) 149-158, 1993.
Inspire Record 355918 DOI 10.17182/hepdata.28845

We have investigated the properties of jet production in almost real γγ collisions at √ s =58 GeV with the TOPAZ detector at the TRISTAN e + e − collider. The data were analyzed with a jet-clustering method based on a cone algorithm. The jet rate shows evidence for a hard scattering effect of the hadronic constituents of a photon (resolved photon processes). We have also observed a substantial energy flow in the small-angle region, which is additional evidence for resolved photon processes. We present the transverse momentum dependence of the inclusive jet and two-jet cross sections and compare them with different model predictions.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


Mass identified particle production in proton anti-proton collisions at s**(1/2) = 300-GeV, 540-GeV, 1000-GeV, and 1800-GeV

The E735 collaboration Alexopoulos, T. ; Allen, C. ; Anderson, E.W. ; et al.
Phys.Rev.D 48 (1993) 984-997, 1993.
Inspire Record 363171 DOI 10.17182/hepdata.22669

The yields and average transverse momenta of pions, kaons, and antiprotons produced at the Fermilab p¯p collider at s=300, 540, 1000, and 1800 GeV are presented and compared with data from the energies reached at the CERN collider. We also present data on the dependence of average transverse momentum 〈pt〉 and particle ratios as a function of charged particle density dNcdη; data for particle densities as high as six times the average value, corresponding to a Bjorken energy density 6 GeV/fm3, are reported. These data are relevant to the search for quark-gluon phase of QCD.

11 data tables
Table 1

PT RANGE FROM 0 TO INFINITY.

Table 2

PT RANGE FROM 0 TO INFINITY.

Table 3

No description provided.

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