Alexandrov, Yu.
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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.


PRODUCTION OF Tb-149 FROM Gd, Tb, Ho, Tm, Ta, Au BY 1-GeV PROTONS

Alexandrov, A.A. ; Konev, V.G. ; Mironov, Yu.T. ;
LENINGRAD-87-1339, 1987.
Inspire Record 253912 DOI 10.17182/hepdata.38001

None

1 data table
Table 1

No description provided.


Measurement of $D$(s)* - $D$(s) Mass Difference

The ARGUS collaboration Albrecht, H. ; Binder, U. ; Bockmann, P. ; et al.
Phys.Lett.B 207 (1988) 349-354, 1988.
Inspire Record 251558 DOI 10.17182/hepdata.29950

Using the ARGUS detector at DORIS, we observe the production of D ∗+ s mesons in e + e − annihilation through their subsequent decays to a D + s and a photon. Photons which convert in the beam pipe or drift chamber inner wall are used to obtain a high precision measurement of the D ∗+ s -D + s mass difference, while photons detected in the shower counters are used to determine the production cross section, and to provide an independent measurement of the D ∗+ s -D + s mass difference. The observed D ∗+ s - D + s mass difference is 142.5±0.8±1.5 MeV/ c 2 , and σ(e + e − →D ∗+ s X)·BR(D ∗+ s →D + s γ)(·BR(D + s →φπ + ) is 4.4±1.1±1.0 pb at 10.2 GeV. The width of the D ∗+ s is less than 4.5 MeV/ c 2 at 90% confidence level.

1 data table
Table 1

Cross sections uncorrected for branching ratios.


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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rivet Analysis
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
Table 1

TOPOLOGICAL CROSS SECTION.

Table 2

(K*0 K*BAR0) cross section.

Table 3

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

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rivet Analysis
Determination of $\alpha^- s$ From a Measurement of the Direct Photon Spectrum in $\Upsilon$ (1s) Decays

The ARGUS collaboration Albrecht, H. ; Andam, A.A. ; Binder, U. ; et al.
Phys.Lett.B 199 (1987) 291-296, 1987.
Inspire Record 248655 DOI 10.17182/hepdata.30061

Using the ARGUS detector at the DORIS II e + e − storage ring we have measured direct photons from the decay ???(1 S )→ γgg . The ratio R γ = Γ (???(1S)→ γgg )/ Γ (???(1S)→ ggg )=(3.00±0.13±0.18)% has been determined, from which we deduce values of the strong coupling constant α s =0.225±0.011±0.019 and the QCD scale parameter Λ MS =115±17±28 MeV defined in the modified minimal-subtraction scheme. The shape of the measured spectrum clearly rules out the predictions of the lowest order QCD calculations.

1 data table
Table 1

No description provided.


Strangeness and Diquark Suppression Factors in 360-{GeV}/$c p p$ Interactions

The EHS-RCBC collaboration Bailly, J.L. ; Banerjee, S. ; Bartl, W. ; et al.
Phys.Lett.B 195 (1987) 609-612, 1987.
Inspire Record 247012 DOI 10.17182/hepdata.30121

From the measurements of the inclusive production ratios between π - , K - and p̄ at Feynman x = 0 in 360 GeV/ c pp interactions and using the predictions of the Lund fragmentation model, we determine the strangeness and diquark suppression factors and find γ s , l = 0.28 ± 0.03 and γ D , l = 0.063 ± 0.011 .

1 data table
Table 1

No description provided.


Search for Direct $\gamma$ Production at Low Transverse Momentum in 63-{GeV} $p p$ Collisions

The Axial Field Spectrometer collaboration Akesson, T. ; Albrow, M.G. ; Almehed, S. ; et al.
Phys.Rev.D 36 (1987) 2615, 1987.
Inspire Record 246577 DOI 10.17182/hepdata.23325

We have searched for direct photons of low PT (≤1.0 GeV/c) at θc.m.=90° in pp collisions at √s =63 GeV. We used two independent methods: direct detection in NaI crystals and conversion to e+e− pairs. No signal is observed; the photon spectrum is well described by the decay of hadrons. The result is consistent with a direct low-PT photon signal reported at √s =12 GeV, but excludes a rapid growth of soft-photon production with √s .

1 data table
Table 1

No description provided.


rivet Analysis
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
Table 1

Topological cross section.

Table 2

OMEGA RHO0 Production cross section.


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
Table 1

Topological cross section. 14 pct systematic uncertainty not included.

Table 2

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

Table 3

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