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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
Table 1

No description provided.

Table 2

Topological cross section.

Table 3

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
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.


PROMPT ELECTRON PRODUCTION IN e+ e- ANNIHILATIONS AT 29-GeV

The TPC/Two Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Badtke, D.H. ; et al.
Z.Phys.C 27 (1985) 39, 1985.
Inspire Record 200040 DOI 10.17182/hepdata.1895

We have measured the inclusive prompt electron cross section over a wide momentum range (P>0.5 GeV/c) with the PEP-4 TPC detector. The semielectronic branching fractions of thec andb quarks are (9.1±0.9 (stat.)±1.3 (syst.))% and (11.0±1.8±1.0)%, respectively. Theb quark fragmentation function peaks at highz with 〈zb〉=0.74±0.05±0.03. The axial couplings to the neutral current areac=2.3±1.4±1.0 for thec quark andab=−2.0±1.9±0.5 for theb quark.

3 data tables match query
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


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
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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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
Table 1

Topological cross section.

Table 2

OMEGA RHO0 Production cross section.


Inclusive D*+- production in two photon collisions at LEP

The L3 collaboration Achard, P. ; Adriani, O. ; Aguilar-Benitez, M. ; et al.
Phys.Lett.B 535 (2002) 59-69, 2002.
Inspire Record 585623 DOI 10.17182/hepdata.54885

Inclusive D^{*+-} production in two-photon collisions is studied with the L3 detector at LEP, using 683 pb^{-1} of data collected at centre-of-mass energies from 183 to 208 GeV. Differential cross sections are determined as functions of the transverse momentum and pseudorapidity of the D^{*+-} mesons in the kinematic region 1 GeV < P_T < 12 GeV and |eta| < 1.4. The cross sections sigma(e^+e^- -> e^+e^-D^{*+-}X) in this kinematical region is measured and the sigma(e^+e^- -> e^+e^- cc{bar}X) cross section is derived. The measurements are compared with next-to-leading order perturbative QCD calculations.

4 data tables match query
Table 1

Visible D*+- production cross section in the given phase space range. Data are given for each D* decay channel, and the average.

Table 2

Total cross section for open charm production. Data are given for each D* decay channel, and the combined average. The second systematic (DSYS) error is the uncertainty on the extrapolation from the visible to the full phase space region.

Table 3

The measured D*+- production cross section in the region ABS(ETARAP) < 1.4.The DSIG/DPT points refer to the centre of the bin and the SIG points are the integrated over the bin.

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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
Table 1

TOPOLOGICAL CROSS SECTION.

Table 2

95 PCT CL UPPER LIMITS.


Inclusive transverse momentum distributions of charged particles in diffractive and nondiffractive photoproduction at HERA

The ZEUS collaboration Derrick, M. ; Krakauer, D. ; Magill, S. ; et al.
Z.Phys.C 67 (1995) 227-238, 1995.
Inspire Record 392037 DOI 10.17182/hepdata.44775

Inclusive transverse momentum spectra of charged particles in photoproduction events in the laboratory pseudorapidity range $-1.2<\eta<1.4$ have been measured up to $p_{T}=8\GeV $ using the ZEUS detector. Diffractive and non--diffractive reactions have been selected with an average $\gamma p$ centre of mass (c.m.) energy of $\langle W \rangle = 180\GeV$. For diffractive reactions, the $p_{T}$ spectra of the photon dissociation events have been measured in two intervals of the dissociated photon mass with mean values $\langle M_{X} \rangle = 5$ GeV and $10$ GeV. The inclusive transverse momentum spectra fall exponentially in the low $p_{T}$ region. The non--diffractive data show a pronounced high $p_{T}$ tail departing from the exponential shape. The $p_{T}$ distributions are compared to lower energy photoproduction data and to hadron--hadron collisions at a similar c.m. energy. The data are also compared to the results of a next--to--leading order QCD calculation.

3 data tables match query
Table 1

Rate of charged particle production in an average non-diffractive event.

Table 2

Rate of charged particle production in an average event with a diffractively dissociated photon state of mass M(X) = 5 GeV.

Table 3

Rate of charged particle production in an average event with a diffractively dissociated photon state of mass M(X) = 10 GeV.


rivet Analysis
Observation of the Charmed Baryon $\Sigma(c$) in $e^+ e^-$ Annihilations

The ARGUS collaboration Albrecht, H. ; Bockmann, P. ; Glaser, R. ; et al.
Phys.Lett.B 211 (1988) 489-492, 1988.
Inspire Record 261672 DOI 10.17182/hepdata.29913

Using the ARGUS detector at the DORIS II storage ring, we have observed the charmed baryons Σ c ++ and Σ c 0 , through their decays to Λ c + π ± . We have measured the mean Σ c −Λ c + mass difference as 167.6±0.3±1.6 MeV/ c 2 . The isospin mass splitting between the Σ c ++ and the Σ c 0 was found to be 1.2±0.7±0.3 MeV/ c 2 . The rate of Λ c + production from Σ c decays was found to be (36±12±11)% of the total rate of Λ c + production. The Σ c χ p spectrum was observed to be similar to that of the Λ c + , with a Peterson function parameter ϵ of 0.29±0.06.

1 data table match query
Table 1

DATA FROM UPSI(4S) WAS EXCLUDED.


rivet Analysis
Measurement of K^+K^- production in two-photon collisions in the resonant-mass region

The Belle collaboration Abe, Kazuo ; Abe, Koya ; Abe, T. ; et al.
Eur.Phys.J.C 32 (2003) 323-336, 2003.
Inspire Record 629334 DOI 10.17182/hepdata.50324

K^+K^- production in two-photon collisions has been studied using a large data sample of 67 fb^{-1} accumulated with the Belle detector at the KEKB asymmetric e^+e^- collider. We have measured the cross section for the process gamma gamma -> K^+ K^- for center-of-mass energies between 1.4 and 2.4 GeV, and found three new resonant structures in the energy region between 1.6 and 2.4 GeV. The angular differential cross sections have also been measured.

8 data tables match query
Table 1

Cross section for two photon production of K+ K- in the polar angular region ABS(COS(THETA*)) < 0.6.

Table 2

Differential cross sections DSIG/DCOS(THETA) for the W range 1.40 to 1.56 GeV.. Statistical errors only.

Table 3

Differential cross sections DSIG/DCOS(THETA) for the W range 1.56 to 1.72 GeV.. Statistical errors only.

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