Adhya, S.P.
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Tests of QED at 29-GeV Center-Of-Mass Energy

Bender, D. ; Derrick, M. ; Fernandez, E. ; et al.
Phys.Rev.D 30 (1984) 515, 1984.
Inspire Record 199464 DOI 10.17182/hepdata.23593

During the initial data run with the High Resolution Spectrometer (HRS) at SLAC PEP, an integrated luminosity of 19.6 pb−1 at a center-of-mass energy of 29 GeV was accumulated. The data on Bhabha scattering and muon pair production are compared with the predictions of QED and the standard model of electroweak interactions. The measured forward-backward charge asymmetry in the angular distribution of muon pairs is -8.4%±4.3%. A comparison between the data and theoretical predictions places limits on alternative descriptions of leptons and their interactions. The existence of heavy electronlike or photonlike objects that alter the structure of the QED vertices or modify the propagator are studied in terms of the QED cutoff parameters. The Bhabha-scattering results give a lower limit on a massive photon and upper limits on the effective size of the electron of Λ+>121 GeV and Λ−>118 GeV at the 95% confidence level. Muon pair production yields Λ+>172 GeV and Λ−>172 GeV. If electrons have substructure, the magnitude and character of the couplings of the leptonic constituents affects the Bhabha-scattering angular distributions to such an extent that limits on the order of a TeV can be extracted on the effective interaction length of the components. For models in which the constituents interact with vector couplings of strength g24π∼1, the energy scale ΛVV for the contact interaction is measured to be greater than 1419.0 GeV at the 95% confidence level. We set limits on the production of supersymmetric scalar electrons through s-channel single-photon annihilation and t-channel inelastic scattering. Using events with two noncollinear electrons and no other charged or observed neutral particles in the final state, we see one event which is consistent with a simple supersymmetric model but which is also consistent with QED. This allows us to exclude the scalar electron to 95% confidence level in the mass range 1.8 to 14.2 GeV/c2.

3 data tables
Table 1

Comparison of Bhabhas with QED.

Table 2

Muon angular distributions.

Table 3

Forward-backward asymmetry from full angular range.


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.


rivet Analysis
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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AZIMUTHAL ASYMMETRY OF NEGATIVELY CHARGED HADRONS IN THE REACTION ANTI-NEUTRINO N ---> MU+ H- X

Ammosov, V.V. ; Asratian, A.E. ; Berge, J.P. ; et al.
JETP Lett. 38 (1983) 248-251, 1983.
Inspire Record 202188 DOI 10.17182/hepdata.69924

None

2 data tables
Table 1

No description provided.

Table 2

No description provided.


PROPERTIES OF D* PRODUCTION IN e+ e- ANNIHILATION AT 29-GeV

The HRS collaboration Ahlen, S.P. ; Akerlof, C. ; Baranko, G. ; et al.
HRS-CP-83-3, 1983.
Inspire Record 192098 DOI 10.17182/hepdata.13343

None

2 data tables
Table 1

D* FRAGMENTATION FUNCTION.

Table 2

R VALUE IS RADIATIVELY CORRECTED (BUT NOT CROSS SECTION).


COMPTON EFFECT ON pi- MESON

Antipov, Yu.M. ; Batarin, V.A. ; Bessubov, V.A. ; et al.
Z.Phys.C 24 (1984) 39, 1984.
Inspire Record 193860 DOI 10.17182/hepdata.41183

The reaction π−A→Aπ− γ at 40 GeV/c was studied on “Sigma” spectrometer on six different nuclear targets in the region of four-momentum transfer |t|<0.05 (GeV/c)2. A phenomenon of elastic scattering of pions on the nuclear Coulomb field photons was observed, its total and differential cross sections were measured. The cross section of Compton effect on π−-meson was measured.

6 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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MEASUREMENT OF THE ASYMMETRY OF THE REACTION gamma p ---> p pi0 CROSS-SECTION FOR PION PRODUCTION ANGLES IN CMS 65-degrees TO 80-degrees IN THE RESONANCE ENERGY RANGE

Avakian, R.O. ; Bagdasaryan, A.S. ; Vartapetian, G.A. ; et al.
Sov. J. Contemp. Phys. 19 ( 1984) No. 1 46-48. ( Izv. Akad. Nauk Arm. SSR 19 ( 1984) No. 1 50-53) and Erevan Phys. Inst. - EFI-674(64)-83 (83,REC.JAN.84) 13p, 1983.
Inspire Record 195991 DOI 10.17182/hepdata.18465

None

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


THE RATIO OF THE X DISTRIBUTIONS FOR ANTI-NEUTRINOS INTERACTIONS IN NEON AND DEUTERIUM

Asratian, A.E. ; Efremenko, V.I. ; Fedotov, A.V. ; et al.
ITEP-110-1983, 1983.
Inspire Record 192049 DOI 10.17182/hepdata.40367

None

2 data tables
Table 1

No description provided.

Table 2

No description provided.


POLARIZATION OF RECOIL PROTONS IN THE GAMMA P ---> P PI0 REACTION FOR THE CMS ANGLE THETA (PI) = 80-DEGREES AT THE ENERGY OF E (GAMMA) = 0.7-GEV - 1.4-GEV. (IN RUSSIAN)

Bratashevsky, A.S. ; Zybalov, A.A. ; Karasev, S.P. ; et al.
Yad.Fiz. 38 (1983) 390-392, 1983.
Inspire Record 195468 DOI 10.17182/hepdata.17715

None

1 data table
Table 1

THETA IS THETA(P=4,RF=CM) IN DEG.


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.

More…