Dubrovin, M.S.
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Observation of Three Upsilon States

The CLEO collaboration Andrews, D. ; Berkelman, Karl ; Billing, M. ; et al.
Phys.Rev.Lett. 44 (1980) 1108, 1980.
Inspire Record 152393 DOI 10.17182/hepdata.20733

Three narrow resonances have been observed in e+e− annihilation into hadrons at total energies between 9.4 and 10.4 GeV. Measurements of mass spacing and ratios of lepton pair widths support the interpretation of these "ϒ" states as the lowest triplet-S levels of the bb¯ quark-antiquark system.

1 data table
Table 1

No description provided.


Observation of a Fourth Upsilon State in e+ e- Annihilations

The CLEO collaboration Andrews, D. ; Berkelman, Karl ; Cabenda, R. ; et al.
Phys.Rev.Lett. 45 (1980) 219, 1980.
Inspire Record 153182 DOI 10.17182/hepdata.20674

A fourth state in the upsilon energy region has been seen in e+e− collisions at the Cornell Electron Storage Ring. A resonance is observed with a mass 1112±5 MeV above the lowest upsilon state. The 9.6-MeV rms width is greater than the 4.6-MeV energy resolution of the e+e− beams. The observed characteristics of the new state make it a likely candidate for the 4S3 state of the bb¯ system, lying above the threshold for the production of B mesons.

1 data table
Table 1

NOT CORRECTED FOR TAU HEAVY LEPTON PRODUCTION NOR TWO-PHOTON COLLISIONS.


Measurements of the Properties of d Meson Decays

Schindler, R.H. ; Alam, M.S. ; Boyarski, A. ; et al.
Phys.Rev.D 24 (1981) 78, 1981.
Inspire Record 156644 DOI 10.17182/hepdata.24006

We present a study of the decay properties of charmed D mesons produced near the peak of the ψ′′(3770) resonance in e+e− annihilation. Branching fractions for nine Cabibbo-favored and three Cabibbo-suppressed decay modes are presented along with upper limits on one additional Cabibbo-favored and four additional Cabibbo-suppressed decay modes. A study of Kππ-decay-mode Dalitz plots reveals a large quasi-two-body pseudoscalar-vector component for the D0 decays and an apparent nonuniform population on the Dalitz plot for the D+ decay into K−π+π+. Using tagged events, we measure the charged-particle multiplicity and strange-particle content of D decays. A measurement of the D+ and D0 semileptonic decay fractions indicates that the D+ has a significantly longer lifetime than the D0.

1 data table
Table 1

INCLUSIVE CROSS SECTIONS UNCORRECTED FOR RADIATIVE EFFECTS.


Direct Photon Production at the $\psi$

Scharre, D.L. ; Alam, M.S. ; Boyarski, A. ; et al.
Phys.Rev.D 23 (1981) 43, 1981.
Inspire Record 153865 DOI 10.17182/hepdata.24079

We present results of a detailed analysis of inclusive direct photon production at the ψ(3095). The direct-photon momentum distribution for x>0.4 is presented and compared with the leading-order quantum-chromodynamic prediction. The total production rate is found to be consistent with theoretical expectations, but the observed momentum distribution is considerably softer. Results of an analysis of some inclusive properties of the hadronic system recoiling against the direct photon are presented. The mean charged-particle and Ks multiplicities are presented as functions of the invariant mass of the hadronic system. These data agree well with the corresponding mean multiplicities measured in e+e− annihilations at center-of-mass energies comparable to the invariant mass of the hadronic system.

4 data tables
Table 1

TOTAL INCLUSIVE PHOTON MOMENTUM SPECTRUM. ERRORS ARE STATISTICAL ONLY.

Table 2

PHOTON SPECTRUM PREDICTED FROM MEASUREMENT OF THE PI0 AND ETA DISTRIBUTIONS. ERRORS INCLUDE BOTH STATISTICAL AND RELATIVE SYSTEMATIC COMPONENTS.

Table 3

INCLUSIVE PI0 MOMENTUM DISTRIBUTION. QUOTED ERRORS ARE STATISTICAL ONLY. OVERALL AND RELATIVE SYSTEMATIC ERRORS ARE LESS THAN 30 PCT AND MAY VARY SLOWLY WITH X.

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Measurement of asymmetry in spin dependent e p resonance region scattering.

Baum, Guenter ; Bergstrom, M.R. ; Clendenin, J.E. ; et al.
Phys.Rev.Lett. 45 (1980) 2000, 1980.
Inspire Record 154062 DOI 10.17182/hepdata.20698

The first measurements are reported of the asymmetry in resonance-region scattering of longitudinally polarized electrons by longitudinally polarized protons. Data have been obtained at Q2=0.5 and 1.5 (GeV/c)2 in the missing-mass range W=1.1−1.9 GeV. Results are compatible with a multipole analysis of single-pion electroproduction. The spin-dependent behavior is consistent with a duality mechanism as in the unpolarized case.

4 data tables
Table 1

ELECTRON ASYMMETRY AT Q**2 ABOUT 0.5 GEV**2.

Table 2

ELECTRON ASYMMETRY AT Q**2 ABOUT 1.5 GEV**2.

Table 3

PHOTON ASYMMETRY AT Q**2 ABOUT 0.5 GEV**2.

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Study of the Interference Correlations Between Pions in $K^- p$ Interactions at 32-{GeV}/$c$

Babintsev, V.V. ; Bryzgalov, V.V. ; Bryukhanova, T.M. ; et al.
Sov.J.Nucl.Phys. 34 (1981) 412, 1981.
Inspire Record 155763 DOI 10.17182/hepdata.41486

None

4 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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$\pi^\pm$ Meson Spectra in the Inclusive Reaction $\gamma C \to \pi X$ Caused by Bremsstrahlung $\gamma$ Quanta With the Maximum Energy 4.5-{GeV}

Alanakian, K.V. ; Amarian, M.D. ; Demirchyan, R.A. ; et al.
JETP Lett. 32 (1980) 652, 1980.
Inspire Record 158531 DOI 10.17182/hepdata.18460

None

1 data table
Table 1

DISTRIBUTIONS INTEGRATED WITH PHOTON SPECTRUM ARE NORMALIZED ON NUMBER OF EQUIVALENT PHOTONS.


A-dependence of Inclusive $\pi^\pm$ Meson Photoproduction

Alanakian, K.V. ; Amarian, M.D. ; Demirchyan, R.A. ; et al.
Sov.J.Nucl.Phys. 34 (1981) 50, 1981.
Inspire Record 159969 DOI 10.17182/hepdata.18445

None

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


Excitation Function of Photoproduction of Cumulative Protons on Nuclei

Alanakian, K.V. ; Amarian, M.D. ; Demirchyan, R.A. ; et al.
EFI-456-63-80-YEREVAN, 1980.
Inspire Record 159970 DOI 10.17182/hepdata.18446

None

2 data tables
Table 1

No description provided.

Table 2

DATA WERE OBTAINED BY SUBTRACTION METHOD. TO OBTAIN NORMALIIZED INVARIANT CROSS SECTION DATA FROM PR D8, 226 WERE USED.


A Measurement of the Cross-Section for Four Pion Production in gamma gamma Collisions at SPEAR

Burke, D.L. ; Abrams, G.S. ; Alam, M.S. ; et al.
Phys.Lett.B 103 (1981) 153-156, 1981.
Inspire Record 165016 DOI 10.17182/hepdata.31168

We present a measurement of the cross section for the reaction e + e − → e + e − π + π − π + π − at SPEAR. This channel is found to be large and dominated by the process γγ → ϱ 0 ϱ 0 → π + π − π + π − . The cross section, which is small just above the four-pion threshold, exhibits a large enhancement near the ϱ 0 ϱ 0 threshold.

1 data table
Table 1

Axis error includes +- 0.0/0.0 contribution (THE QUOTED ERRORS INCLUDE VARIOUS SYSTEMATIC ERRORS ADDED QUADRATICALLY).