Shimansky, S.S.
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Charged $D^*$ Production in $e^+ e^-$ Annihilation at 29-{GeV} and a Limit on D0 - Anti-d0 Mixing

Yamamoto, H. ; Atwood, W.B. ; Baillon, P. ; et al.
Phys.Rev.Lett. 54 (1985) 522-525, 1985.
Inspire Record 205132 DOI 10.17182/hepdata.20325

We have studied inclusive D*± production using the DELCO detector at PEP. Our technique involved kaon identification in the momentum range above 3.2 GeV/c using a threshold gas Čerenkov counter. This leads to a model-independent upper limit on D0−D¯0 mixing of 8.1% (90% confidence level). We also have measured the charm fragmentation function, which peaks at x≡PD*(Ebeam2−MD*2)12 of 0.56±0.06(stat.), and the total cross section for D* production, σ(D*±)=0.140±0.021(stat.)±0.032(syst.) nb (x>0.3, with radiative correction).

2 data tables
Table 1

No description provided.

Table 2

SYSTEMATIC ERROR DOES NOT INCLUDE THE UNCERTAINTY ON THE BRANCHING RATIOS USED.


Search for $D^*$ Production in Pion Nucleon Interactions

Fitch, V.L. ; Montag, A.D. ; Palestini, S. ; et al.
Phys.Rev.D 33 (1986) 1486-1487, 1986.
Inspire Record 232140 DOI 10.17182/hepdata.23545

Results are presented of a measurement of the production of D*+ (D*−) in 250-GeV/c π−N interactions. We observe 2.1±7.8 events corresponding to a charge-D* cross section σ(D*) of 0.4±1.5 μb/nucleon. When averaged with our previous measurement made at 200 GeV/c, the result is σ(D*)=2.3±1.0 μb/nucleon with (dσ/dx)‖x=0=4.6±2.0 μb.

3 data tables
Table 1

THIS DATA FROM PREVIOUS PUBLICATION : PRL 46, 761 (1981).

Table 2

No description provided.

Table 3

No description provided.


Prompt Electron Production From Delco at {PEP}

The DELCO collaboration Pal, T. ; Atwood, W.B. ; Barish, B.C. ; et al.
Phys.Rev.D 33 (1986) 2708, 1986.
Inspire Record 226886 DOI 10.17182/hepdata.23516

We report final results on prompt electron production in hadronic events from e+e− annihilations at √s =29 GeV, obtained with the DELCO detector at the SLAC storage ring PEP. We find the semielectronic branching ratios of charm and bottom quarks to be B(c→se+νe)=(11.6−0.9 +1.1)% and B(b→ce−ν¯e)=(14.9−1.9 +2.2)% respectively. These results, from the complete data set, are consistent with an earlier analysis of partial data and indicate hard fragmentation functions for both c and b quarks, with mean values 〈zc〉=0.59±0.04 and 〈zb〉=0.72±0.05. The errors indicated here are a combination of statistical and systematic uncertainties.

4 data tables
Table 1

Axis error includes +- 0.0/0.0 contribution (NOT GIVEN).

Table 2

Axis error includes +- 0.0/0.0 contribution (NOT GIVEN).

Table 3

Axis error includes +- 0.0/0.0 contribution (NOT GIVEN).

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Suppression of Valence Quark Recombination in $\pi^+$ Fragmentation Into $\rho^+$

The EHS/NA22 collaboration Adamus, M. ; Azhinenko, I.V. ; Belokopytov, Yu.A. ; et al.
Phys.Lett.B 183 (1987) 425, 1987.
Inspire Record 238678 DOI 10.17182/hepdata.30207

We present inclusive ϱ ±,0 and ω cross sections in the beam fragmentation region of π + p interactions at 250 GeV/ c . The near equality of the ϱ + and ϱ 0 cross sections implies suppression of valence quark recombination in forward vector meson production.

1 data table
Table 1

No description provided.


Single Diffraction Dissociation in $\pi^+ p$ and $K^+ p$ Interactions at 250-{GeV}/$c$

The EHS/NA22 collaboration Adamus, M. ; Azhinenko, I.V. ; Almeida, F.M.L., Jr. ; et al.
Z.Phys.C 39 (1988) 301, 1988.
Inspire Record 254506 DOI 10.17182/hepdata.15646

None

1 data table
Table 1

No description provided.


Measurements of r and a Search for Heavy Quark Production in e+ e- Annihilation at s**(1/2) = 50-GeV and 52-GeV

The AMY collaboration Sagawa, H. ; Mori, T. ; Abe, K. ; et al.
Phys.Rev.Lett. 60 (1988) 93, 1988.
Inspire Record 251270 DOI 10.17182/hepdata.20143

The ratio R of the cross section for e+e− annihilation into hadronic final states to the QED cross section for muon-pair production is measured to be 4.34±0.45±0.30 and 4.23±0.20±0.21 at c.m. energies of 50 and 52 GeV, respectively. From these values of R and an analysis of the event shapes we deduce a 95%-confidence-level upper limit for the production rate of new heavy charge +23e or −13e quarks to be 0.19 units of R.

1 data table
Table 1

No description provided.


MEASUREMENTS OF CROSS-SECTIONS AND CHARGE ASYMMETRIES FOR e+ e- ---> tau+ tau- AND e+ e- ---> mu+ mu- FOR S**(1/2) FROM 52-GeV TO 57-GeV

The AMY collaboration Bacala, A. ; Malchow, R.L. ; Sparks, K. ; et al.
Phys.Lett.B 218 (1989) 112-118, 1989.
Inspire Record 265797 DOI 10.17182/hepdata.51370

Measurements of the differential cross sections for e + e − →μ + μ − and e + e − →τ + τ − at values of s from 52 to 57 GeV are reported. The forward-backward asymmetries and the total cross sections for these reactions are found to be in agreement with predictions of the standard model of the electro-weak interactions. These measurements are used to extract values of the weak coupling constant g v e g v l and g A e g A l , where l = μ or τ .

11 data tables
Table 1

Axis error includes +- 5/5 contribution (Included in the quoted errors for the total cross sections. The main contribution to SYS-ERR are the systematic uncertainty in the luminosity measurement and the uncertainty in the computer modeling of the various efficiencies and backgrounds).

Table 2

Axis error includes +- 5/5 contribution (Included in the quoted errors for the total cross sections. The main contribution to SYS-ERR are the systematic uncertainty in the luminosity measurement and the uncertainty in the computer modeling of the various efficiencies and backgrounds).

Table 3

No description provided.

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MEASUREMENTS OF THE e+ e- TOTAL HADRONIC CROSS-SECTION AND A DETERMINATION OF M(Z) AND LAMBDA (MS)

The AMY collaboration Mori, T. ; Nozaki, T. ; Blanis, D. ; et al.
Phys.Lett.B 218 (1989) 499-507, 1989.
Inspire Record 276653 DOI 10.17182/hepdata.29847

The total cross section for e + e − annihilation into hadrons has been measured for CM energies ranging from 50 to 57 GeV. We fit the predictions of the standard model to these measurements and those at lower energies. The mass of the Z 0 boson, M Z , and the QCD scale parameter, Λ MS , are derived from the fit. The results are M Z =88.6 −1.8 +2.0 GeV/ c 2 , and Λ MS =0.15 −0.11 +0.16 GeV .

1 data table
Table 1

No description provided.


Experimental Evidence for the Nonabelian Nature of {QCD}

The AMY collaboration Park, I.H. ; Schnetzer, S. ; Green, J. ; et al.
Phys.Rev.Lett. 62 (1989) 1713, 1989.
Inspire Record 276619 DOI 10.17182/hepdata.20045

We present evidence for the non-Abelian nature of QCD from a study of multijet events produced in e+e− annihilations from √s =50 to 57 GeV in the AMY detector at the KEK storage ring TRISTAN. A comparison of the three-jet event fraction at TRISTAN to the fraction of the DESY storage ring PETRA shows that the QCD coupling strength αs decreases with increasing Q2. In addition, measurements of the angular distributions of four-jet events show evidence for the triple-gluon vertex.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


A MEASUREMENT OF e+ e- ---> b anti-b FORWARD - BACKWARD CHARGE ASYMMETRY BETWEEN s**(1/2) = 52-GeV AND 57-GeV

The AMY collaboration Sagawa, H. ; Lim, J. ; Abe, K. ; et al.
Phys.Rev.Lett. 63 (1989) 2341, 1989.
Inspire Record 279824 DOI 10.17182/hepdata.19996

Using 123 multihadronic inclusive muon-production e+e− annihilation events at an average c.m. energy of 55.2 GeV, we extracted the forward-backward charge asymmetry of the e+e−→bb¯ process and the R ratio for bb¯ production. We used an analysis method in which the behavior of the c quark and lighter quarks is assumed, with only that of the b quark left indeterminate. The results, Ab=-0.72±0.28(stat)±0.13(syst) and Rb=0.57±0.16±0.10, are consistent with the standard model.

2 data tables
Table 1

Asymmetry in BOTTOM quark production.

Table 2

Ratio of BOTTOM quark production to total hadron cross section (R value).