Alexopoulos, T.
DSIG/DZ
[20.0, 30.0]
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rivet Analysis
D*+ Production in e+ e- Annihilation at 29-GeV

Yelton, J.M. ; Feldman, G.J. ; Goldhaber, G. ; et al.
Phys.Rev.Lett. 49 (1982) 430, 1982.
Inspire Record 177606 DOI 10.17182/hepdata.20572

The production of the charmed meson state D*+ has been observed in e+e− annihilation at 29 GeV. The fragmentation function for charmed quarks appears to be peaked about z=0.5.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

UPDATED RESULT REPORTED AS PRELIMINARY IN G. TRILLING, PARIS CONFERENCE 1982.


Production of Charmed Particles in 250-GeV mu+ - Iron Interactions

The European Muon collaboration Aubert, J.J. ; Bassompierre, G. ; Becks, K.H. ; et al.
Nucl.Phys.B 213 (1983) 31-64, 1983.
Inspire Record 180921 DOI 10.17182/hepdata.46965

Dimuon and trimuon events produced by the interaction of 250 GeV muons in an iron target have been studied and are shown to originate predominantly from charm production. The data are used to measure the contribution of charm to the nucleon structure function F 2 . The cross sections for real photoproduction ( Q 2 =0) of charm in the current fragmentation region are derived as a function of photon energy and are found to be ∼0.6% of the total, hadronic photoproduction cross section in this energy range. The measured cross sections are found to be well represented by the photon-gluon fusion model. The charmed quark fragmentation function is obtained by using this model to fit the measured decay muon energy distribution and is found to be well represented by exp(1.6±1.6) Z . The data are used to study the momentum distribution of the gluons in the nucleon. An upper limit of 1.4% (90% confidence level) is set on the branching ratio D→ μν and a model-dependent upper limit on the branching ratio F→ μν is derived.

9 data tables
Table 1

The charm contribution to the nucleon structure function from the dimuon data.

Table 2

No description provided.

Table 3

No description provided.

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Inclusive $D$ and $D^*$ Production in $e^+ e^-$ Annihilation at 29-{GeV}

The HRS collaboration Ahlen, S.P. ; Akerlof, C. ; Baranko, G. ; et al.
Phys.Rev.Lett. 51 (1983) 1147, 1983.
Inspire Record 191536 DOI 10.17182/hepdata.20523

Inclusive production of (D0, D¯0) and D± mesons have been observed in e+e− annihilation at 29 GeV. The signals correspond to R values of R(D0+D¯0)=3.25±1.2 and R(D++D−)=1.35±0.6. D*± production is also observed via the process D*+→D0π+ and its charge conjugate. The D and D* production rates are compared.

7 data tables
Table 1

EXTRAPOLATION TO ALL Z.

Table 2

EXTRAPOLATION TO ALL Z.

Table 3

EXTRAPOLATION TO ALL Z.

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$\rho^0$ Production in Deep Inelastic $\mu p$ Interactions

The European Muon collaboration Aubert, J.J. ; Bassompierre, G. ; Becks, K.H. ; et al.
Phys.Lett.B 133 (1983) 370-374, 1983.
Inspire Record 192074 DOI 10.17182/hepdata.30613

Inclusive ϱ 0 meson production has been measured in 120 GeV and 280 GeV muon-proton interactions. Distributions of z and p T 2 are presented. Primary ϱ 0 production is found to be equal to that of π 0 production within errors.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Charm Quark Production and Fragmentation in $e^+ e^-$ Annihilation at 29-{GeV}

Derrick, M. ; Fernandez, E. ; Fries, R. ; et al.
Phys.Lett.B 146 (1984) 261-265, 1984.
Inspire Record 202898 DOI 10.17182/hepdata.51261

The electroweak production asymmetry and the decay fragmentation function for e + e − → c c have been measured at s = 29 GeV using charged D ∗ production over the full kinematic range. The data were taken at PEP using the High Resolution Spectrometer. The measured asymmetry is −0.12 ± 0.08. The total production cross section in units of the point cross section corrected for initial state radiation is R D ∗ = 2.7 ± 0.9 .

2 data tables
Table 1

ASSUMES SIG(D*+) = SIG(D*0). (EXPT. MEASURES D*+ PRODUCTION ONLY). R VALUE CORRECTED FOR INITIAL STATE RADIATION.

Table 2

No description provided.


Inclusive D0 and $D^+$ Production in $e^+ e^-$ Annihilation at 29-{GeV}

Derrick, M. ; Fernandez, E. ; Fries, R. ; et al.
Phys.Rev.Lett. 53 (1984) 1971, 1984.
Inspire Record 202899 DOI 10.17182/hepdata.51258

We have observed inclusive production of D0 and D+ mesons, and their charge conjugates, in e+e− annihilation at 29 GeV on the basis of a data sample of 106 pb−1. These signals correspond to R values of R(D0+D―0)=1.8±0.5 and R(D++D−)=1.2±0.4. Taking the D+ and D0 data together, we measure a charge asymmetry of A=−0.08±0.12 for charmed quarks. A comparison of R(D+D―) with R(D*+D―*) obtained via the process D*+→D0π+ gives a DD* ratio of 1.0−0.2+0.3, indicating that direct D* production dominates over direct D production.

4 data tables
Table 1

No description provided.

Table 2

EXTRAPOLATED TO ALL Z.

Table 3

No description provided.

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rivet Analysis
Study of Quark Fragmentation at 29-GeV: Global Jet Parameters and Single Particle Distributions

Bender, D. ; Derrick, M. ; Fernandez, E. ; et al.
Phys.Rev.D 31 (1985) 1, 1985.
Inspire Record 201482 DOI 10.17182/hepdata.23581

In this paper, results are presented from a study of the hadronic final states in e+e− annihilation at 29 GeV. The data were obtained with the High Resolution Spectrometer (HRS) at the SLAC PEP e+e− colliding-beam facility. The results are based on 6342 selected events corresponding to an integrated luminosity of 19.6 pb−1. The distributions of the events in sphericity (S), thrust (T), and aplanarity (A) are given and compared to other e+e− data in the same energy range. We measure 〈S〉=0.130±0.003±0.010 and 〈1-T〉=0.100±0.002. The sphericity distribution is compared to sphericity measurements made for beam jets in hadronic collisions as well as jets studied in neutrino scattering. The data sample is further reduced to 4371 events with the two-jet selections, S≤0.25 and A≤0.1. The single-particle distributions in the longitudinal and transverse directions are given. For low values of the momentum fraction (z=2p/W), the invariant distribution shows a maximum at z∼0.06, consistent with a QCD expectation. The data at high Feynman x (xF) show distribution consistent with being dominated by a (1-xf)2 variation for the leading quark-meson transition. The rapidity distribution shows a shallow central minimum with a height (1/NevdNh/dY‖Y=0=2.3±0.02±0.07. The mean charged multiplicity is measured to be 〈nch〉=13.1±0.05±0.6. The mean transverse momentum relative to the thrust axis 〈pT〉 rises as a function of z to a value of 0.70±0.02 GeV/c for z≳0.3. The distributions are compared to those measured in other reactions.

25 data tables
Table 1

New values supplied 6.7.87 by M.Derrick.

Table 2

No description provided.

Table 3

New values supplied 6.7.87 by M. Derrick.

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Evidence for the $F^*$ meson

The TPC/Two Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Badtke, D.H. ; et al.
Phys.Rev.Lett. 53 (1984) 2465, 1984.
Inspire Record 203890 DOI 10.17182/hepdata.20409

Evidence for a narrow state decaying into an F meson and a photon has been obtained in e+e− annihilation events at 29-GeV c.m. energy. This state lies 139.5 ± 8.3(stat.) ± 9.7(syst.) MeV above the F-meson mass and is consistent with the expected F* meson. The F mesons are identified by a peak in the K+K−Kπ± mass at 1.948±0.028±0.010 GeV.

2 data tables
Table 1

DATA REQUESTED FROM AUTHORS.

Table 2

IN (K+K-PI+) THE AUTHORS INCLUDE OTHER DECAY MODES SUCH AS (AK*0 K+),(PHI PI+),(K+ K- PI+,PI0),(K+ K- MU+ NU) WHICH CANNOT BE RESOLVED.


rivet Analysis
Production of $\phi$ and F (1970) $\to \phi \pi$ in $e^+ e^-$ Annihilation at 29-{GeV}

Derrick, M. ; Fernandez, E. ; Fries, R. ; et al.
Phys.Rev.Lett. 54 (1985) 2568, 1985.
Inspire Record 213242 DOI 10.17182/hepdata.20340

Data from the high-resolution spectrometer at PEP have been used to study the inclusive production of φ mesons and F± mesons decaying into φπ±. Fragmentation functions and cross sections are presented and compared to existing data. The total φ cross section at 29 GeV is 40±6 pb. The observed F signal in the region z>0.4, given the assumption that R(F)[R(F)+R(D)]=0.15, corresponds to an F→φπ branching ratio of (3.3±1.1)%. The measured F mass is 1963±3±3 MeV/c2.

5 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

WITH THE FOLLOWING ANGLE CUTS ON THE DECAY REGIONS. PHI DECAY - ABS(COS(THETA)) >0.5.

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Neutral $K^*$ (890) and $\rho^0$ Meson Production in $e^+ e^-$ Annihilation at the $\sqrt{s}=29$-{GeV}

Derrick, M. ; Kooijman, P. ; Loos, J.S. ; et al.
Phys.Lett.B 158 (1985) 519-524, 1985.
Inspire Record 16663 DOI 10.17182/hepdata.30388

The production of neutral K ∗ (890) and ρ 0 mesons was studied in e + e − annihilation at s =29 GeV using the High Resolution Spectrometer at PEP. Differential cross sections are presented as a function of the scaled energy variable z and compared to π 0 and K 0 production. The measured multiplicities are 0.84±0.08 ϱ 0 mesons and 0.57±0.09 K ∗0 (890) mesons per event for a meson momentum greater than 725 MeV/ c . The ratios of vector meson to pseudoscalar meson production for (u,d), s and c quark are compared to predictions of the Lund model.

3 data tables
Table 1

Data requested from authors.

Table 2

No description provided.

Table 3

No description provided.