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.

1 data table match query

No description provided.


Evidence for Lambda/c(2593)+ production.

The ARGUS collaboration Albrecht, H. ; Hamacher, T. ; Hofmann, R.P. ; et al.
Phys.Lett.B 402 (1997) 207-212, 1997.
Inspire Record 440304 DOI 10.17182/hepdata.44624

Using the ARGUS detector at the e + e − storage ring DORIS II at DESY, we have found evidence for the production of the excited charmed baryon state Λ c (2593) + in the channel Λ c + π + π − . Its mass was determined to be (2594.6±0.9±0.4) MeV/c 2 , and the natural width measured to be Γ = (2.9 −2.1−1.4 +2.9+1.8 ) MeV. The production cross section times the branching ratios of σ ( e + e − → Λ c (2593) + X ) × Br ( Λ c (2593) + → Λ c + π + π − ) × Br ( Λ c + → pK − π + ) was measured to be (0.25 −0.13 +0.24 ±0.13) pb. The fractions of Λ c (2593) + decays proceeding through the Σ c 0 π + and Σ c ++ π − channels were determined to be 0.29±0.10±0.11 and 0.37±0.12±0.13, respectively.

1 data table match query

Results with and without extrapolation.


A Measurement of $\gamma \gamma \to \rho^+ \rho^-$

The ARGUS collaboration Albrecht, H. ; Bockmann, P. ; Glaser, R. ; et al.
Phys.Lett.B 217 (1989) 205-210, 1989.
Inspire Record 266416 DOI 10.17182/hepdata.29853

The reaction γγ → ϱ + ϱ − → π + π − π 0 π 0 has been studied with the ARGUS detector at the e + e − storage ring DORIS II at DESY. Near threshold, the cross section for this reaction is about four times smaller than for the reaction γγ → ϱ 0 ϱ 0 .

4 data tables match query

Data read from graph.

Data read from graph.

Data read from graph.

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First Observation of $\gamma \gamma \to K^*+ K^*$-

The ARGUS collaboration Albrecht, H. ; Bockmann, P. ; Glaser, R. ; et al.
Phys.Lett.B 212 (1988) 528-532, 1988.
Inspire Record 262713 DOI 10.17182/hepdata.29893

The final states K S 0 K S 0 π + π − and K S 0 K ∓ π 0 π ± , produced in two-photon reactions, have been studied using the ARGUS detector at the e + e − storage ring DORIS II at DESY. The reaction γγ→ K ∗+ K ∗− has been observed for the first time. Its cross section is about eight times larger than that for γγ→ K ∗0 K ∗0 , but it has a similar W γγ dependence.

4 data tables match query

No description provided.

Topological cross section.

Topological cross section.

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First Observation of $\gamma \gamma \to \omega \omega$

The ARGUS collaboration Albrecht, H. ; Andam, A.A. ; Binder, U. ; et al.
Phys.Lett.B 198 (1987) 577-582, 1987.
Inspire Record 247566 DOI 10.17182/hepdata.30070

The reaction γγ → 2 π + 2 π − 2 π 0 has been studied using the ARGUS detector at the e + e − storage ring DORIS II at DESY. Production of ω mesons is observed and, in particular, the reaction γγ → ωω is seen for the first time. The cross section for γγ → ωω has an enhancement at ∼ 1.9 GeV/ c 2 of about 10 nb. The cross sections for γγ → 2 π + 2 π − 2 π 0 and γγ → ωπ + π − π 0 are also given.

3 data tables match query

Topological cross section. 14 pct systematic uncertainty not included.

Cross section for (omega omega) production. Additional 25 pct systematic error not included.

Cross section for (omega pi+ pi- pi0) where (omega omega) events have been removed. Additional 15 pct systematic error not included.


First Observation of $\gamma \gamma \to \omega \rho^0$

The ARGUS collaboration Albrecht, H. ; Andam, A.A. ; Binder, U. ; et al.
Phys.Lett.B 196 (1987) 101, 1987.
Inspire Record 247567 DOI 10.17182/hepdata.30104

The reaction γγ → 2 π + 2 π − π 0 has been studied using the the ARGUS detector at the e + e − storage ring DORIS II at DESY. The production of the vector-meson pair ωϱ 0 is observed for the first time. The cross section for γγ → ωϱ 0 and the topological cross section for γγ → 2 π + 2 π − π 0 are given. The angular distribution in ωϱ 0 events do not indicate any specific dominant spin-parity; they are consistent with isotropic production and decay of the ω and ϱ 0 mesons over the available W γγ range.

2 data tables match query

Topological cross section.

OMEGA RHO0 Production cross section.


Observation of the Decay $D(s$)+ $\to \eta^\prime \pi^+$

The ARGUS collaboration Albrecht, H. ; Ehrlichmann, H. ; Glaser, R. ; et al.
Phys.Lett.B 245 (1990) 315-320, 1990.
Inspire Record 295620 DOI 10.17182/hepdata.45150

Using the ARGUS detector at the e + e - storage ring DORIS II at DESY, we have observed the decay D s + → η'π + in two decay modes of the η'. We measure the ratio of branching ratios BR(D s + → η'π + )/BR(D s + → Øπ + ) to be 2.5±0.5±0.3.

1 data table match query

The cross section times Br(D/S+ --> ETAPRIME PI+), but is not included the ETAPRIME branching ratio.


First Observation of $\gamma \gamma \to K^*0 \bar{K}^*$0

The ARGUS collaboration Albrecht, H. ; Andam, A.A. ; Binder, U. ; et al.
Phys.Lett.B 198 (1987) 255-260, 1987.
Inspire Record 248680 DOI 10.17182/hepdata.30080

The final state K + K − π + π − has been studied in γγ interactions using the ARGUS detector at the e + e − storage ring DORIS II at DESY. Production of the vector meson pair K ∗0 (892) K ∗0 (892) is observed for the first time. The cross section for K + K − π + π − , K ∗0 K − π + +c.c. and K ∗0 K ∗0 are all found to be of the order of a few nb. In the W γγ range accessible, a mean upper limit of 0.5 nb at 95% CL is derived for φϱ 0 production.

6 data tables match query

TOPOLOGICAL CROSS SECTION.

(K*0 K*BAR0) cross section.

(K*0 K- PI+ + CC) CROSS SECTION WITH (K*0 K*BAR0) REMOVED.

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A Search for $\omega \phi$ and $\phi \phi$ Production in the Reactions $\gamma \gamma \to K^+ K^- \pi^+ \pi^- \pi^0$ and $\gamma \gamma \to 2 K^+ 2 K^-$

The ARGUS collaboration Albrecht, H. ; Bockmann, P. ; Glaser, R. ; et al.
Phys.Lett.B 210 (1988) 273-277, 1988.
Inspire Record 260828 DOI 10.17182/hepdata.29918

The reaction γγ→K + K − π + π − π 0 has been observed for the first time, using the ARGUS detector at the e + e − storage ring DORIS II at DESY. The cross section shows an enhancement for W γγ close to 3 GeV/ c 2 . Searches for γγ→ωφ and for γγ→φφ leading to this final state, as well as for γγ→φφ→2K + 2K − , have been performed. The derived upper limits for ωφ and φφ production are compatible with q q q q model predictions.

2 data tables match query

TOPOLOGICAL CROSS SECTION.

95 PCT CL UPPER LIMITS.


Observation of Spin Parity 2+ Dominance in the Reaction $\gamma \gamma \to \rho^0 \rho^0$ Near Threshold

The ARGUS collaboration Albrecht, H. ; Ehrlichmann, H. ; Glaser, R. ; et al.
Z.Phys.C 50 (1991) 1-10, 1991.
Inspire Record 296187 DOI 10.17182/hepdata.45136

The reactionγγ→π+π−π+π− has been studied with the ARGUS detector. The rate in the invariant mass region below 1.8 GeV/c2 is found to be largely due toρ0ρ0 production. A spin-parity analysis shows a dominance of the partial wave (JP,Jz)=(2+, 2) with a small admixture fromJP=0+. The contribution of negative parity states is consistent with zero. The large ratio of cross sectionsσ(γγ→ρ0ρ0)/σ(γγ→ρ+ρ−)≃4, and the dominance of theJP=2+ wave in the reactionγγ→ρ0ρ0 is a signature consistent with the production of an exotic (I=2) resonance.

5 data tables match query

No description provided.

Statistical errors only.. Cross-section assuming phase-space distribution, as obtained by a 7 parameter fit.

Statistical errors only.. Cross-section assuming phase-space distribution, as obtained by a 7 parameter fit.

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