Observation of double charm production involving open charm in pp collisions at $\sqrt{s}$=7 TeV

The LHCb collaboration Aaij, R ; Abellan Beteta, C ; Adeva, B ; et al.
JHEP 06 (2012) 141, 2012.
Inspire Record 1113596 DOI 10.17182/hepdata.66915

The production of $J/\psi$ mesons accompanied by open charm, and of pairs of open charm hadrons are observed in pp collisions at a centre-of-mass energy of 7 TeV using an integrated luminosity of $355pb^{-1}$ collected with the LHCb detector. Model independent measurements of absolute cross-sections are given together with ratios to the measured $J/\psi$ and open charm cross-sections. The properties of these events are studied and compared to theoretical predictions.

52 data tables

Normalized differential cross-section $d\ln\sigma(pp\rightarrow J/\psi D^0 X)/dp_T(J/\psi)$ for $2<y(J/\psi)<4$, $p_T(J/\psi)<12$ GeV/$c$, $2<y(D^0)<4$, $3<p_T(D^0)<12$ GeV/$c$ region.

Normalized differential cross-section $d\ln\sigma(pp\rightarrow J/\psi D^+ X)/dp_T(J/\psi)$ for $2<y(J/\psi)<4$, $p_T(J/\psi)<12$ GeV/$c$, $2<y(D^+)<4$, $3<p_T(D^+)<12$ GeV/$c$ region.

Normalized differential cross-section $d\ln\sigma(pp\rightarrow J/\psi D_s^+ X)/dp_T(J/\psi)$ for $2<y(J/\psi)<4$, $p_T(J/\psi)<12$ GeV/$c$, $2<y(D_s^+)<4$, $3<p_T(D_s^+)<12$ GeV/$c$ region.

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Systematic Study of K pi Production in the Reaction K+- p --> K0(s) pi+- p: Technique and Measurements at 10-GeV/c

Baldi, R. ; Bohringer, T. ; Dorsaz, P.A. ; et al.
Nucl.Phys.B 134 (1978) 365-391, 1978.
Inspire Record 122145 DOI 10.17182/hepdata.8292

A two-arm spectrometer for simple event topologies is described. Its main characteristics are: (i) large solid-angle acceptance for the forward emitted particles, owing to the absence of magnetic-momentum analysis; (ii) high-resolution time-of-flight measurement of the recoil proton, in the momentum-transfer range 0.05 < | t | < 1 (GeV/ c ) 2 ; (iii) high data-taking rate and on-line pattern recognition.

6 data tables

No description provided.

No description provided.

K*(892)+ REGION.

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A Partial Wave Analysis of the $K^- \phi$ System Produced in the Reaction $K^- p \to K^+ K^- K^- p$ at 18.5-{GeV}/$c$

The Bari-Birmingham-CERN-Milan-Paris-Pavia collaboration Armstrong, T. ; Baubillier, M. ; Beusch, W. ; et al.
Nucl.Phys.B 221 (1983) 1-15, 1983.
Inspire Record 180924 DOI 10.17182/hepdata.33954

About 15 000 K − Φp events have been collected in the CERN Ω′ spectrometer. A partial-wave decomposition of the K − Φ system is performed. The 1 + SO + wave is dominant. The 0 − P0 + and 2 − P0 + waves are important and show resonant behaviour at ∼ 1.83 GeV (Γ ∼ 0.25 GeV) and ∼ 1.73 GeV (Γ ∼ 0.22 GeV) respectively. The first one can be interpreted as the second radial excitation of the kaon while the second one can be identified as one of the two L mesons.

2 data tables

No description provided.

PARTIAL WAVE AMPLITUDE SHOWING POSSIBLE EXISTENCE OF L MESON AT 1.73 GEV (WIDTH = 0.22 GEV) AND RADIAL EXCITATION OF THE KAON AT 1.83 GEV (WIDTH = 0.25 GEV).


A Study of Two Photon Production of Two-body Final States With Invariant Mass Greater Than 2.0-{GeV}

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Grigull, R. ; et al.
Nucl.Phys.B 202 (1982) 189-200, 1982.
Inspire Record 176691 DOI 10.17182/hepdata.34157

We have measured the electron, muon, and charged-hadron pair production rates in two-phonon interactions for invariant masses above 2.0 GeV over a large of momentum transfer. The cross sections for electron and muon pairs show good agreement with the QED predictions at both small and large momentum transfer. The observed rate of hadron production is less than 6% of the rate that QED predicts for point-like hadrons, consistent with recent leading-order QCD calculations.

5 data tables

LOW Q**2 CROSS SECTIONS.

DIFFERENTIAL CROSS SECTIONS IN THE INVARIANT MASS FOR MUON AND ELECTRON PAIRS IN THE UNTAGGED, LOW Q**2 REGION.

HIGH Q**2 CROSS SECTIONS.

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Hadron and Hadron Pair Production at Large Transverse Momentum in $p \bar{p}$ and $p p$ Interactions at the {ISR}

The Axial Field Spectrometer collaboration Akesson, T. ; Albrow, M.G. ; Almehed, S. ; et al.
Phys.Lett.B 121 (1983) 439-444, 1983.
Inspire Record 182425 DOI 10.17182/hepdata.30813

We have measured the production of one and two large transverse momentum hadrons in p p and pp interactions in the range 2 < p T < 6 GeV/ c for the central rapidity region |y| < 0.9 at s = 63 and 31 GeV . No statistically significant difference between p p and pp collisions is observed. The results are in accordance with lowest order QCS perturbative calculations and rule out a large contribution of Constituent Interchange Model (CIM), di-quark of quark-fusion subprocesses in this kinematic range.

2 data tables

No description provided.

No description provided.


Formation of the Tensor Mesons A2 (1320) in Photon-photon Interactions

The PLUTO collaboration Berger, Christoph ; Deuter, A. ; Genzel, H. ; et al.
Phys.Lett.B 149 (1984) 427-432, 1984.
Inspire Record 204847 DOI 10.17182/hepdata.30478

We have measured the reaction γγ → π + π − π 0 using the PLUTO detector at PETRA. A pronounced enhancement is seen in the π + π − π 0 mass distribution corresponding to the A 2 meson. The event configuration in this enhancement favors a 2 + spin-parity assignment. The value of Γ γγ =1.06 ±0.18±0.19 keV obtained for the two-photon decay width of the A 2 agrees with previous measurements and with quark model predictions.

1 data table

No description provided.


Measurement of the Radiative Width of the $\eta^\prime$ (958) in Two Photon Interactions

The TASSO collaboration Althoff, M. ; Braunschweig, W. ; Kirschfink, F.J. ; et al.
Phys.Lett.B 147 (1984) 487-492, 1984.
Inspire Record 203795 DOI 10.17182/hepdata.30481

The reaction e + e − →e + e − η ′(958) has been observed by detecting the final state π + π − γ . The two-photon width of the η′ has been measured to be Γ ( η ′→ γγ ) = 5.1±0.4±0.7 keV. A search for the ι (1440) has been made in the ϱ 0 γ final state. An upper limit has been obtained for the product Γ ( ι (1440) → γ ) gg ), B ( ι → ϱ 0 γ ) < 1.5 keV (95%CL).

1 data table

No description provided.


Measurement of Exclusive $\eta^\prime$ Production in $\gamma \gamma$ Reactions

The PLUTO collaboration Berger, Christoph ; Deuter, A. ; Genzel, H. ; et al.
Phys.Lett.B 142 (1984) 125-129, 1984.
Inspire Record 201708 DOI 10.17182/hepdata.30533

We observe γγ → η′ production in the reaction e + e − → e + e − π + π − γ. We measure the product γ γγ ( η ′) B ( η ′ → ϱ 0 γ ) to be 1.14 ± 0.08 ± 0.11 keV. A first measurement of the γγ → η′ transition form factor is made for Q 2 up to 1 GeV 2 .

1 data table

No description provided.


Measurement of Very Large Transverse Momentum Jet Production at the CERN anti-p p Collider

The UA2 collaboration Bagnaia, P. ; Banner, M. ; Battiston, R. ; et al.
Phys.Lett.B 138 (1984) 430-440, 1984.
Inspire Record 199645 DOI 10.17182/hepdata.30574

The production of very large transverse momentum hadron jets has been measured in the UA2 experiment at the CERN p p Collider for s = 540 GeV using a highly segmented calorimeter. The range of previously available cross sections for inclusive jet production is extended to p T = 150 GeV and the two-jet invariant mass distribution to m jj = 280 GeV with the largely increased data sample collected during the 1983 running period. The results are compared with the predictions of QCD models.

2 data tables

LISTED ERRORS INCLUDE STATISTICAL AND THE PT-DEPENDENT UNCERTAINTIES. THE ADDITIONAL OVERALL SYSTEMATIC UNCERTAINTY IS 45PCT.

LISTED ERRORS INCLUDE STATISTICAL AND THE M-DEPENDENT UNCERTAINTIES. THE ADDITIONAL OVERALL SYSTEMATIC UNCERTAINTY IS 45PCT.


Hyperon production in the channel p p ---> K+ Lambda p near the reaction threshold

The COSY-TOF collaboration Abdel-Samad, S. ; Bilger, R. ; Bohm, A. ; et al.
Phys.Lett.B 632 (2006) 27-34, 2006.
Inspire Record 710561 DOI 10.17182/hepdata.26998

Hyperon production in the threshold region was studied in the reaction pp→K+Λp using the time-of-flight spectrometer COSY-TOF. Exclusive data, covering the full phase-space, were taken at three different beam momenta pbeam=2.59 , 2.68 and 2.85 GeV/ c (corresponding to excess energies of ɛ=85 , 115 and 171 MeV). Total cross-sections were deduced to be 7.4±0.5 μb , 8.6±0.6 μb and 16.5±0.4 μb , respectively. Differential observables including Dalitz plots were obtained. From the investigation of the Dalitz plot at pbeam=2.85 GeV/c a dominant contribution of the N∗(1650) -resonance to the reaction mechanism was found. In addition the pΛ -final-state interaction turned out to have a significant influence on the Dalitz plot distribution even 171 MeV above threshold.

7 data tables

Measured total cross sections.

Distribution of the invariant mass of the P-LAMBDA subsystem at beam momentum 2.85 GeV.

Distribution of the invariant mass of the K-LAMBDA subsystem at beam momentum 2.85 GeV.

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