HEPData Search

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Measurement of Drell-Yan electron and muon pair differential cross-sections in anti-p p collisions at s**(1/2) = 1.8-TeV

The CDF collaboration Abe, F. ; Albrow, Michael G. ; Amidei, Dante E. ; et al.

Phys.Rev.D 49 (1994) R1-R6, 1994.

Inspire Record 355927 DOI 10.17182/hepdata.42543

We measure the Drell-Yan differential cross section d2σdMdy||y|<1 over the mass range 11<M<150 GeV/c2 using dielectron and dimuon data from p¯p collisions at a center-of-mass energy of s=1.8 TeV. Our results show the 1M3 dependence that is expected from the naive Drell-Yan model. In comparison to the predictions of recent QCD calculations we find our data favor those parton distribution functions with the largest quark contributions in the x interval 0.006 to 0.03.

3 data tables

Table 1

Dielectron differential cross section.

Table 2

Dimuon differential cross section.

Table 3

Drell-Yan differential cross section for combined dielectron and dimuon data. Error includes both statistics and systematics.

Two measurements of B0 anti-B0 mixing

The CLEO collaboration Bartelt, John E. ; Csorna, S.E. ; Egyed, Z. ; et al.

Phys.Rev.Lett. 71 (1993) 1680-1684, 1993.

Inspire Record 354226 DOI 10.17182/hepdata.47247

We have measured the B0B¯0 mixing probability, χd, using a sample of 965 000 BB¯ pairs from Υ(4S) decays. Counting dilepton events, we find χd=0.157±0.016±0.018−0.021+0.028. Using tagged B0 events, we find χd=0.149±0.023±0.019±0.010. The first (second) error is statistical (systematic). The third error reflects a ±15% uncertainty in the assumption, made in both cases, that charged and neutral B pairs contribute equally to dilepton events. We also obtain a limit on the CP impurity in the Bd0 system, ‖Re(εB0)‖<0.045 at 90% C.L.

4 data tables

Table 1

No description provided.

Table 2

Mixing parameter from counting dilepton events. CONST(N=MIXING PARAM) = 1/(1 - LAMBDA(C,N)) * (N(2LEPTON+) + N(2LEPTON-))/(N(LEPTON+,LEPTON-) + N(2LEPTON+) + N(2LEPTON-)). LAMBDA(C,N) is the fraction of dilepton events coming from B+B- decays, LAMBDA(C,N) = f(B+)*Br(B+)**2/(f(B+)*Br(B+)**2 + f(B0)*Br(B0)**2), where f(B+),f(B0) are the productiron fractions of the charged and neutral B's at the UPSI(4S), and Br(B+), Br(B0) are the semileptonic brancing fractions.

Table 3

Mixing parameter from tagged B0 events.

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Transverse momentum of J / psi produced in p Cu, p U, O-16 Cu, O-16 U and S-32 U collisions at 200-GeV per nucleon.

The NA38 collaboration Baglin, C. ; Baldisseri, A. ; Bussiere, A. ; et al.

Phys.Lett.B 262 (1991) 362-368, 1991.

Inspire Record 321322 DOI 10.17182/hepdata.29390

None

8 data tables

Table 1

No description provided.

Table 2

CONTINUUM MUONS ORIGINATE MAINLY FROM VECTOR MESON DECAYS, SEMI-LEPTONIC DECAYS OF D DBAR PAIRS AND FROM DRELL-YAN MECHANISM.

Table 3

No description provided.

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Transverse momentum of dimuons production in p U, O U and S U collisions at 200-GeV/nucleon.

The NA38 collaboration Abreu, M.C. ; Alimi, M. ; Baglin, C. ; et al.

Nucl.Phys.A 525 (1991) 469C-472C, 1991.

Inspire Record 328922 DOI 10.17182/hepdata.36783

Dimuon production m p-U, O-U and S-U collisions has been studied at 200 GeV/N. It is observed that 〈 p T 〉 and 〈 p 2 T 〉 of the J / Ψ transverse momentum distributions increase with the transverse energy of the ion induced reactions. Such a marked behaviour is not seen for muon pairs of the continuum.

4 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Inclusive D*+- production in photon-photon collisions

The TPC/Two-Gamma collaboration Alston-Garnjost, M. ; Avery, R.E. ; Barker, A.R. ; et al.

Phys.Lett.B 252 (1990) 499-504, 1990.

Inspire Record 299662 DOI 10.17182/hepdata.29510

The TPC/Two-Gamma Collaboration has measured the inclusive cross section for production of charmed D ∗± mesons in photon-photon collisions. The reaction utilized was e + e - →e + e - D ∗± X, with D ∗± →D O π +- , D O →K -+ π ± , and either zero or one outgoing e ± detected. The result, σ(e + e - → e + e - D ∗± X) = 74±26±19 pb , is in agreement with the quark parton mo del prediction for e + e - → e + e - c c , combined with a Lund model for the hadronization of the charmed quarks.

2 data tables

Table 1

No description provided.

Table 2

No description provided.

Production of Charmed Mesons in $\gamma \gamma$ Interactions

The TASSO collaboration Braunschweig, W. ; Gerhards, R. ; Kirschfink, F.J. ; et al.

Z.Phys.C 47 (1990) 499-504, 1990.

Inspire Record 294597 DOI 10.17182/hepdata.15178

Production of charmed mesons in γγ-interactions at PETRA energies has been observed in the TASSO detector. Cross sections for inclusiveD*± and$D^0 \bar D^0 $ production have been measured. Neutral and charged meson pairs are estimated to be produced with comparable cross sections, and their sum seems to account for a sizeable fraction of σtot(γγ→hadrons) near the$c\bar c$ threshold.

4 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

Statistical error only.

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