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rivet Analysis
Hyperon Production in $e^+ e^-$ Annihilation at 10-{GeV} Center-of-mass Energy

The ARGUS collaboration Albrecht, H. ; Binder, U. ; Bockmann, P. ; et al.
Z.Phys.C 39 (1988) 177, 1988.
Inspire Record 251097 DOI 10.17182/hepdata.1697

The production cross sections for the Λ, Σ0, Ξ−, Σ0 (1385), Ξ0 (1530) and Ω− hyperons have been measured, both in the continuum and in direct ϒ decays. Baryon rates in direct ϒ decays are enhanced by a factor of 2.5 or more compared to the continuum. Such a large baryon enhancement cannot be explained by standard fragmentation models. The strangeness suppression for baryons and mesons turns out to be the same. A strong suppression of spin 3/2 states is observed.

23 data tables
Table 1

Hyperon rates per multihadronic event in direct UPSILON decays.

Table 2

Hyperon rates per multihadronic event in the continuum.

Table 3

LAMBDA spectrum (1/SIG(had))*D(SIG)/D(X) for UPSILON (1S) direct decays, with X = P/Pmax.

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Observation of a New Charmed Meson.

The ARGUS collaboration Albrecht, H. ; Binder, U. ; Harder, G. ; et al.
Phys.Rev.Lett. 56 (1986) 549, 1986.
Inspire Record 222219 DOI 10.17182/hepdata.20225

Using the ARGUS detector at the DORIS II e+e− storage ring at DESY, we have obtained evidence for a new charmed resonance which decays into D*±(2010)π∓. The observed mass and width are 2420±6 MeV/c2 and 70±21 MeV/c2, respectively. The fragmentation function is found to be hard, as expected for a state containing a leading charm quark produced by nonresonant e+e− annihilation.

2 data tables
Table 1

No description provided.

Table 2

Estimated production cross section obtained by comparison with observed D*(2010) production rate.


rivet Analysis
Observation of the D*0 (2459) in e+ e- Annihilation

The ARGUS collaboration Albrecht, H. ; Bockmann, P. ; Glaser, R. ; et al.
Phys.Lett.B 221 (1989) 422-426, 1989.
Inspire Record 268577 DOI 10.17182/hepdata.29827

Using the ARGUS detector at the DORIS II storage ring at DESY, we have observed a charmed meson of mass (2455±3±5) MeV/c2, decaying to D + π − . The natural width of this state is determined to be (15 +13+5 −10−10 ) MeV c 2 . The fragmentation function is hard, as expected for a leading charmed particle from nonresonant e + e − annihilation. Analysis of the decay angular distribution supports the hypothesis that the observed state is an L =1 excited charmed meson with spin-parity 2 + .

2 data tables
Table 1

Corrected to zero momentum using fragmentation function of Peterson et al., PR D29 (83) 105.

Table 2

Data read from graph.


Observation of the Charmed Baryon $\Lambda(c$) in $e^+ e^-$ Annihilation at 10-{GeV}

The ARGUS collaboration Albrecht, H. ; Bockmann, P. ; Glaser, R. ; et al.
Phys.Lett.B 207 (1988) 109-114, 1988.
Inspire Record 260826 DOI 10.17182/hepdata.29980

Using the ARGUS detector at DORIS II, we have studied the production of the charmed baryon Λ c in e + e − annihilation at centre-of-mass energies near 10 GeV. The Λ c + was seen in the three decay modes pK − π + , Λπ + π − π + and K̄ 0 p, with products of normalized cross section times branching ratio [ R ·Br] of (10.8±1.4±1.2)×10 −3 , 6.6±1.5±0.9)×10 −3 and (6.7±1.4±0.8)×10 −3 respectively. The measured mass for the Λ c was (2283.1±1.7±2.0) MeV/ c 2 . A limit on the decay rates to Λπ + is reported. The fragmentation function of the Λ c was measured.

2 data tables
Table 1

Data requested from authors.

Table 2

No description provided.


Observation of Anti-deuteron Production in Electron - Positron Annihilation at 10-{GeV} Center-of-mass Energy

The ARGUS collaboration Albrecht, H. ; Binder, U. ; Harder, G. ; et al.
Phys.Lett.B 157 (1985) 326-332, 1985.
Inspire Record 214358 DOI 10.17182/hepdata.30409

The production of antideuterons has been observed in electron-positron annihilations at center-of-mass energies around 10 GeV. Antideuterons have been identified unambiguously by their energy loss in the drift chamber, their time-of-flight and the pattern of their energy deposition in the shower counters of the ARGUS detector. The production rate in the momentum range (0.6−1.8) GeV/ c is (1.6 −0.7 +1.0 ) × 10 −5 per hadronic event.

2 data tables
Table 1

Results from 6 antideuterons detected (3 from UPSI(2S), 2 from (IS) and 1 from (4S)).

Table 2

No description provided.


Production and Decay of the F Meson in $e^+ e^-$ Annihilation at 10-{GeV} Center-of-mass Energy

The ARGUS collaboration Albrecht, H. ; Binder, U. ; Drews, G. ; et al.
Phys.Lett.B 153 (1985) 343, 1985.
Inspire Record 207949 DOI 10.17182/hepdata.30425

Using the ARGUS detector at DORIS, we have observed the production of F ± mesons in e + e − annihilation at a centre of mass energy of 10 GeV through their subsequent decays into φπ ± and φπ + π − π ± . The values obtained for [ R (e + e − →FX). Branching Ratio] are (1.47 ± 0.32 ± 0.20)% and (1.63 ± 0.42 ± 0.41)% respectively. The observed mass is (1973.6 ± 2.6 ± 3.0) MeV c 2 . The F momentum spectrum is as expected for the fragmentation of c quarks into charmed mesons, but is somewhat softer than for fragmentation into D ∗ mesons. The relevant angular distributions are consistent with a spin-zero assignment of the F meson.

2 data tables
Table 1

RESULTS OF FITS FOR SPECIFIED DECAY CHANNELS.

Table 2

ACCEPTANCE CORRECTED FRAGMENTATION FUNCTION FOR THE TWO DECAY CHANNELS COMBINED. X IS PF/PMAX. DATA HAVE BEEN READ FROM THE GRAPH.


Production and Decay of the Charged D* Mesons in e+ e- Annihilation at 10-GeV Center-Of-Mass Energy

The ARGUS collaboration Albrecht, H. ; Binder, U. ; Drews, G. ; et al.
Phys.Lett.B 150 (1985) 235-241, 1985.
Inspire Record 204851 DOI 10.17182/hepdata.30448

Using the ARGUS detector at DORIS we have observed the prediction of the charged D ∗ meson in e + e − annihilation at a center of mass energy of 10 GeV. The D ∗ fragmentation function has been measured using the decay channels D ∗+ → D 0 π + and D 0 → K − π + and K − π + π + π − .

2 data tables
Table 1

RESULTS EXTRAPOLATED TO X>O. SYSTEMATIC ERRORS INCLUDED.

Table 2

ERRORS ARE STATISTICAL ONLY.


Evidence for the production of the charmed, doubly strange baryon omega(c) in e+ e- annihilation

The ARGUS collaboration Albrecht, H. ; Cronstrom, H.I. ; Ehrlichmann, H. ; et al.
Phys.Lett.B 288 (1992) 367-372, 1992.
Inspire Record 334018 DOI 10.17182/hepdata.29224

Using the detector ARGUS at the storage ring DORIS II of DESY, we have found evidence for the production of the charmed and doubly strange baryon Ω c through its decay channel Ξ − K − π + π + . Its mass has been determined to be ((2719.0±7.0±2.5)MeV/ c 2 , and the product of production cross section and branching ratio the above channel to be (2.41±0.90±0.30) pb.

1 data table
Table 1

No description provided.


rivet Analysis
Study of Anti-deuteron Production in $e^+ e^-$ Annihilation at 10-{GeV} Center-of-mass Energy

The ARGUS collaboration Albrecht, H. ; Glaser, R. ; Harder, G. ; et al.
Phys.Lett.B 236 (1990) 102-108, 1990.
Inspire Record 283027 DOI 10.17182/hepdata.29735

We report a measurement of the production of antideuterons d in e + e − annihilation at centre-of-mass energies around 10 GeV using the ARGUS detector at the DORIS II storage ring. We observe an enhancement of d production in direct hadronic ϒ (1S) and ϒ (2S) resonance decays. From 21 events width a d candidate the inclusive cross section 1 σ dir had · d σ d p and the production rate of antideuterons are determined. A production rate of (6.0±2.0±0.6) × 10 -5 d per direct hadronic ϒ decay and a 90% CL upper limit of 1.7 × 10 −5 d per e + e − →q q continuum event are obtained. These results are related to antiproton production through a simple model.

1 data table
Table 1

Acceptance corrected, background subtracted momentum spectrum observed in UPSI(1S) and UPSI(2S) resonance decays.


rivet Analysis
Inclusive production of eta-prime (958) and f0 (975) mesons in the upsilon energy region

The ARGUS collaboration Albrecht, H. ; Ehrlichmann, H. ; Hamacher, T. ; et al.
Z.Phys.C 58 (1993) 199-206, 1993.
Inspire Record 342061 DOI 10.17182/hepdata.14425

The inclusive production cross sections of η′ (958) andfo (975) mesons are measured ine+e− annihilation in the nonresonant continuum around\(\sqrt s= 10\) GeV and in decays of the υ resonances using the ARGUS detector. For η′ (958) mesons, a production ratio of η′ (958)/ηdir=0.35±0.24, with ηdir=η−BR(η′→ηX)·η′, is determined in direct υ(1S) decays, which can be partially explained by the pseudoscalar singlet/octet mixing. Forfo(975) production, we obtain a production ratio offo(975)/p(770)°=0.17±0.030 in direct υ(1S) decays. In its production features, thefo(975) behaves like an ordinary meson, though aK\(\bar K\) molecule nature cannot be excluded. The substantial production yield of thefo(975) meson demonstrates the important effect of feeddown from mesons beyond the basic multiples on pseudoscalar and vector meson production.

5 data tables
Table 1

Direct etaprime rates per event for the continuum region (9.36 to 10.45 GeV), the UPSI(1S) (9.46 GeV), UPSI(2S)(10.02 GeV) and UPSI(4S)(10.58 GeV) regions. Data is extrapolated to the full z region.

Table 2

Radiation corrected normalized cross section for F0(975) production in the continuum events.

Table 3

Normalized cross section for F0(975) production in direct UPSI(1S) decays.

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