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Search for high mass narrow resonances in virtual photon photon interactions

The TPC / TWO GAMMA collaboration Aihara, H. ; Alston-Garnjost, M. ; Avery, R.E. ; et al.
Phys.Rev.Lett. 57 (1986) 3245-3248, 1986.
Inspire Record 239032 DOI 10.17182/hepdata.20201

We report on the first search with virtual photon-photon collisions for narrow, neutral resonances with even C parity in the mass range 4.5<W<19 GeV. The data were obtained via the process e+e−→e+e−γ*γ*→e e−+R with both the scattered e+ and e− detected. We find upper limits (95% confidence level) for the partial decay width of a resonance into two photons, ranging from 50 keV at W=4.5 GeV to 10 MeV at W=19 GeV. These limits constrain theoretical models involving neutral composite bosons.

1 data table
Table 1

No description provided.


A Study of the Inclusive $K_s^0$, $\Lambda$, $\bar{\Lambda}$ Production in Diffractive $\gamma$P Interactions

Bhadra, S. ; Appel, J.A. ; Bartlett, D.F. ; et al.
Phys.Rev.Lett. 55 (1985) 2749, 1985.
Inspire Record 217669 DOI 10.17182/hepdata.20275

We have studied inclusive KS, Λ, and Λ¯ photoproduction over the ranges 40<Eγ<170 GeV and forward produced mass 2<MF<10 GeV. We observe equal Λ and Λ¯ production rates and spectra as expected in a diffractive process where the target proton remains unaltered. We show that the fraction of hadronic events with a strange particle produced in events with forward mass MF agrees well with the same measurement in e+e− annihilation at a center-of-mass energy Ec.m.=MF. The x=2PMF distributions of these three particles in the forward-mass rest frame are compared with theoretical predictions.

1 data table
Table 1

No description provided.


$\tau$ Leptonic Branching Ratios and a Search for Goldstone Decay

The MARK-III collaboration Baltrusaitis, R.M. ; Becker, J. ; Blaylock, G. ; et al.
Phys.Rev.Lett. 55 (1985) 1842, 1985.
Inspire Record 215995 DOI 10.17182/hepdata.20284

Pairs of τ leptons produced at s=3.77 GeV have been studied in eμ, ee, and μμ final states. The leptonic branching ratios have been measured to be B(τ→eνν)=(18.2±0.7±0.5)% and B(τ→μνν)=(18.0±1.0±0.6)%. Limits have been set for the two-body decays τ→eG and τ→μG, where G is a light Goldstone boson.

7 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Observation and Study of a Narrow State in a $\Sigma^-$ (1385) $K^+$ System

The Berlin-Budapest-Dubna-Moscow-Prague-Sofiya-Tbilisi collaboration Aleev, A.N. ; Arefev, V.A. ; Balandin, V.P. ; et al.
Z.Phys.C 25 (1984) 205, 1984.
Inspire Record 201523 DOI 10.17182/hepdata.39601

New data on the observation and study of a narrow resonance decaying intoΣ−(1,385)K+ have been obtained. The mass of the resonance is (1,956−6+8) MeV/c2, and its width is (27±15) MeV/c2. The resonance is produced in the diffraction dissociation of neutrons on quasi-free nucleons of carbon nuclei. The slope parameter of the differential cross section inPT2 is (9.9±3.0) (GeV/c)−2. The cross section times the branching ratio is (0.22±0.04) μb per nucleon. The resonance has one of the natural spinparities: 5/2+, 7/2− and so on.

5 data tables
Table 1

YN IS IN ARBITRARY UNITS.

Table 3

ARBITRARY UNITS FOR YN.

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Evidence for Local Compensation of Baryon Number in $e^+ e^-$ Annihilation

The TASSO collaboration Althoff, M. ; Braunschweig, W. ; Kirschfink, F.J. ; et al.
Phys.Lett.B 139 (1984) 126-132, 1984.
Inspire Record 199469 DOI 10.17182/hepdata.27109

We have studied at CM energies of 14, 22 and 30–36.7 GeV e + e − annihilation events in which the hadronic final state contains both a proton and an antiproton in the momentum range 1.0 < p < GeV/ c . We find that such pairs are produced predominantly in the same jet and conclude that baryon-antibaryon production is dominated by a mechanism involving local compensation of baryon number.

2 data tables
Table 1

BACKGROUND SUBTRACTED DATA.

Table 2

BACKGROUND SUBTRACTED DATA.


CHARGED HADRON PRODUCTION IN THE UPSILON REGION

Avery, P. ; Bebek, C. ; Berkelman, Karl ; et al.
PRINT-83-0867, 1983.
Inspire Record 192220 DOI 10.17182/hepdata.12222

None

3 data tables
Table 1

No description provided.

Table 2

NUMBERS ACTUALLY GIVEN IN GREEN 83 (CORNELL CONF, RED = 1291).

Table 3

NUMBERS ACTUALLY GIVEN IN GREEN 83 (CORNELL CONF, RED = 1291). FOR UPSI(4S) PROTON PRODUCTION SEE ALAM 83, PRL 51/1143/83, RED = 1271.


The D0 Spectrum From $B$ Meson Decay

The CLEO collaboration Green, J. ; Hicks, R.G. ; Sannes, F. ; et al.
Phys.Rev.Lett. 51 (1983) 347, 1983.
Inspire Record 190327 DOI 10.17182/hepdata.20493

The inclusive branching fraction for B-meson decay into D0 mesons and the momentum spectrum of the D0's have been measured. 0.8±0.2±0.2 D0 per B decay was found. The shape of the spectrum suggests an interesting picture of B-meson decay.

1 data table
Table 1

NUMBER OF D0'S FROM UPSI(4S) REGION AFTER CORRECTION FOR THE CONTINUUM CONTRIBUTION.


D*+- Production by e+ e- Annihilation Near 34.4-GeV Center-Of-Mass Energy

The TASSO collaboration Althoff, M. ; Braunschweig, W. ; Gather, K. ; et al.
Phys.Lett.B 126 (1983) 493-498, 1983.
Inspire Record 196842 DOI 10.17182/hepdata.30721

D ∗± production via e + e − →D ∗± X has been measured at an average CM energy of 34.4 GeV. The D ∗± energy spectrum is hard, with a maximum near χ = 0.6. The size of the D ∗ cross section, R D ∗ = σ( e + e − → D ∗ X ) σ μμ = 2.50 ± 0.64 ± 0.88 (assuming R D ∗0 = R D ∗+ ) indicates that a large fraction of charm quark production yields D ∗ mesons. The D ∗± angular distribution exhibits a forward—backward asymmetry, A = −0.28 ± 0.13. This is consistent with that expected in the standard theory for weak neutral currents and leads to | g A c | = 0.89 ± 0.44 for the axial vector coupling of the charm quark.

3 data tables
Table 1

ASSUMES EQUAL RATES FOR CHARGED AND NEUTRAL D*'S. ONLY CHARGED ARE DETECTED.

Table 2

DATA PEAKS AT X=0.6 TO 0.8.

Table 3

ASYMMETRY MEASUREMENT. THETA IS THE ANGLE BETWEEN THE E- AND THE D*.


rivet Analysis
Inclusive $\rho^0$ Production in $e^+ e^-$ Annihilation at High-energy

The TASSO collaboration Brandelik, R. ; Braunschweig, W. ; Gather, K. ; et al.
Phys.Lett.B 117 (1982) 135-140, 1982.
Inspire Record 179022 DOI 10.17182/hepdata.6664

We have observed ϱ 0 production in e + e − annihilation to hadrons at high energies. The differential cross section at a centre of mass energy W , of 34 GeV, is presented. In the range 0.2< x < 0.7, we measure 0.33 ± 0.06 (stat.) ± 0.07 (syst.), 0.22 ± 0.06 ± 0.05 and 0.22 ± 0.02 ± 0.05 ϱ 0 /event at W = 14, 22 and 34 GeV respectively.

10 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

INTEGRATION OVER RESTRICTED X RANGE.

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Observation of Semileptonic Decays of Charmed Baryons

Vella, E. ; Trilling, G. ; Abrams, G.S. ; et al.
Phys.Rev.Lett. 48 (1982) 1515, 1982.
Inspire Record 176986 DOI 10.17182/hepdata.19674

Direct electrons are observed in baryon events produced in e+e− annihilation at center-of-mass energies above the ΛcΛ¯c threshold. These events are attributed to charmed-baryon pair production and subsequent Λc semileptonic decay. Various semileptonic branching ratios of the Λc are determined, including B(Λc→e+X)=(4.5±1.7)%.

2 data tables
Table 1

ELECTRON-BARYON RATIO ABOVE AND BELOW LAMBDA/C THRESHOLD.

Table 2

No description provided.