Halpern, H.
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Observation of Structures in the p p Total Cross-Section Difference of Pure Helicity States in the Mass Range of 2100-MeV to 2500-MeV

Auer, I.P. ; Colton, E. ; Halpern, H. ; et al.
Phys.Rev.Lett. 41 (1978) 354-356, 1978.
Inspire Record 135492 DOI 10.17182/hepdata.20831

We have measured the difference between the pp total cross sections for parallel and antiparallel longitudinal spin states at beam momenta of 1.0, 1.1, 1.30, 1.58, 1.71, 2.1, and 2.25 GeV/c in a transmission counter experiment. These results reveal new structure in the plab range of 1.0 to 2.5 GeV/c.

1 data table match query
Table 1

No description provided.


Observation of a New Structure in the Difference Between the $p p$ Total Cross-sections for Antiparallel and Parallel Longitudinal Spin States

Auer, I.P. ; Colton, E. ; Halpern, H. ; et al.
Phys.Rev.D 34 (1986) 2581, 1986.
Inspire Record 230143 DOI 10.17182/hepdata.23425

We have measured the difference between the pp total cross sections for parallel and antiparallel longitudinal spin states at beam momenta of 2.75, 2.92, 3.25, and 3.48 GeV/c. These results reveal possible new structure in this momentum range.

1 data table match query
Table 1

Data read from graph. Statistical errors only.


Search for light long-lived neutral particles produced in $pp$ collisions at $\sqrt{s} =$ 13 TeV and decaying into collimated leptons or light hadrons with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abbott, Dale Charles ; et al.
Eur.Phys.J.C 80 (2020) 450, 2020.
Inspire Record 1752519 DOI 10.17182/hepdata.91132

Several models of physics beyond the Standard Model predict the existence of dark photons, light neutral particles decaying into collimated leptons or light hadrons. This paper presents a search for long-lived dark photons produced from the decay of a Higgs boson or a heavy scalar boson and decaying into displaced collimated Standard Model fermions. The search uses data corresponding to an integrated luminosity of 36.1 fb$^{-1}$ collected in proton-proton collisions at $\sqrt{s} =$ 13 TeV recorded in 2015-2016 with the ATLAS detector at the Large Hadron Collider. The observed number of events is consistent with the expected background, and limits on the production cross section times branching fraction as a function of the proper decay length of the dark photon are reported. A cross section times branching fraction above 4 pb is excluded for a Higgs boson decaying into two dark photons for dark-photon decay lengths between 1.5 mm and 307 mm.

19 data tables match query
Table 1

Upper limits at 95% CL on the cross section times branching fraction for the process $H \to 2\gamma_d + X$ with $m_H$ = 125 GeV in the muon-muon final state.

Table 2

Upper limits at 95% CL on the cross section times branching fraction for the process $H \to 4\gamma_d + X$ with $m_H$ = 125 GeV in the muon-muon final state.

Table 3

Upper limits at 95% CL on the cross section times branching fraction for the process $H \to 2\gamma_d + X$ with $m_H$ = 800 GeV in the muon-muon final state.

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The Production of Beauty Particles in $\pi^-$ U Interactions at 320-{GeV} Energy

The WA78 collaboration Catanesi, M.G. ; Muciaccia, M.T. ; Natali, S. ; et al.
Phys.Lett.B 187 (1987) 431-436, 1987.
Inspire Record 235069 DOI 10.17182/hepdata.6522

B B production in π − -uranium interactions has been observed at 320 GeV beam energy looking at events with three muons in the final state. The cross section is found to be σ B B = 4.5±1.4±1.4 nb per nucleon (for a linear A -dependence) or σ B B = 17.6±5.5±5.5 nb per nucleon (assuming A 0.75 dependence). An estimate of x F distribution is given.

1 data table match query
Table 1

BEAUTY INCLUSIVE SPECTRA WAS ASSUMED TO BE E*D(SIG)/D(X)/D(PT**2) = EXP(-0.9*PT**2)*(1-ABS(X))**A. THE BEST FIT FOR A IS A = 2.5.


Observation of phi phi production in the reaction anti-p p --> 4 K+- at 1.4-GeV/c incident anti-p momentum

The JETSET collaboration Bertolotto, L. ; Buzzo, A. ; Debevec, P.T. ; et al.
Phys.Lett.B 345 (1995) 325-334, 1995.
Inspire Record 382894 DOI 10.17182/hepdata.48237

The JETSET (PS202) experiment at CERN-LEAR searches for hadronic resonances by means of in-flight antiproton-proton annihilations in the reaction p p → φφ . In order to obtain sufficient luminosity and good final-state mass resolution, this experiment uses an internal hydrogen-cluster jet target intersecting the LEAR antiproton beam. We report on the study of the reaction p p → 4K ± at 1.4 GeV / c incident p̄ momentum, and we present the first experimental observation of a stro φφ signal in this reaction.

2 data tables match query
Table 1

No description provided.

Table 2

No description provided.


$\Lambda$(c)+ Production and Semileptonic Decay in 29-{GeV} $e^+ e^-$ Annihilation

Klein, S. ; Himel, T. ; Abrams, G.S. ; et al.
Phys.Rev.Lett. 62 (1989) 2444, 1989.
Inspire Record 277034 DOI 10.17182/hepdata.20042

We present results on Λc+ production in 29-GeV e+e− annihilation. The Λc+ are observed via their semileptonic decays to Λe+X and Λμ+X. With radiative corrections, we find σ(e+e−→Λc+X)〉BΛc+→eΛX)= 1.5±0.6±0.5 pb or 0.0038±0.0015±0.0012 Λc+→Λe+X decay per hadronic event, and σ(e+e−Λc+X)B(Λc+→μΛX)= 1.4±1.4±0.4 pb or 0.0035±0.0035±0.0011 Λc+→Λμ+X decay per hadronic event. These results can be used to place constraints on the predictions of various production models.

2 data tables match query
Table 1

Cross sections * branching ratio for LAMBDA/C+ production in LAMBDA E+ decay channel.

Table 2

Cross sections * branching ratio for LAMBDA/C+ production in LAMBDA MU+ decay channel.


Photoproduction of pi^0 eta on protons and the Delta(1700)D_{33} resonance

The Crystal Ball at MAMI & TAPS & A2 collaborations Kashevarov, V.L. ; Fix, A. ; Aguar-Bartolome, P. ; et al.
Eur.Phys.J.A 42 (2009) 141-149, 2009.
Inspire Record 811783 DOI 10.17182/hepdata.52974

Total and differential cross sections for the reaction gamma p -> pi^o eta p have been measured with the Crystal Ball/TAPS detector using the tagged photon facility at the MAMI C accelerator in Mainz. In the energy range E_gamma=0.95-1.4 GeV the reaction is dominated by the excitation and sequential decay of the Delta(1700)D33 resonance. Angular distributions measured with high statistics allow us to determine the ratio of hadronic decay widths \Gamma_{\eta \Delta}/\Gamma_{\pi S11} and the ratio of the helicity amplitudes A_{3/2}/A_{1/2} for this resonance.

5 data tables match query
Table 1

Total cross section for the GAMMA P --> PI0 ETA P reaction.. Statistical erros only.

Table 2

The differential cross section as a function of cos(theta(pi0) in the canonical(K) reference frame.. Statistical erros only.

Table 3

The differential cross section as a function of phi(pi0) in the canonical(K) reference frame.. Statistical erros only.

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A Determination of electroweak parameters from Z0 decays into charged leptons

The L3 collaboration Adeva, B. ; Adriani, O. ; Aguilar-Benitez, M. ; et al.
Phys.Lett.B 250 (1990) 183-192, 1990.
Inspire Record 299253 DOI 10.17182/hepdata.29552

We have measured the partial widths for the three reactions e + e − → Z 0 → e + e − , μ + μ − , τ + τ − . The results are Γ ee = 84.3±1.3 MeV, √ Γ ee Γ μμ =83.9±1.4 MeV, and √ Γ ee Γ ττ =83.9±1.4 MeV, where the errors are statistical. The systematic errors are estimated to be 1.0 MeV, 0.9 MeV, and 1.4 MeV, respectively. We perform a simultaneous fit to the cross sections for the e + e − →e + e − , μ + μ − , and τ + τ − data, the differential cross section as a function of polar angle for the electron data, and the forward- backward asymmetry for the muon data. We obtain the leptonic partial with Γ ℓℓ =84.0±0.9 (stat.) MeV. The systematic error is estimated to be 0.8 MeV. Also, we obtain the axial-vector and vector weak coupling constants of charged leptons, g A =−0.500±0.003 and g ν =−0.064 −0.013 +0.017 .

5 data tables match query
Table 1

Cross section from 1990 data.

Table 2

Visible cross section obtained using the cuts required by Method I (see text of paper). (1989 and 1990 data).

Table 3

Visible cross section obtained using the cuts required by Method II (see text of paper). (1989 and 1990 data). RE = E+ E- --> E+ E- (GAMMA).

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Multiparticle production from e+ e- interactions at high energy

Bartoli, B. ; Felicetti, F. ; Ogren, H. ; et al.
Phys.Lett.B 36 (1971) 598-602, 1971.
Inspire Record 69109 DOI 10.17182/hepdata.28392

Measurements of multiple particle production at ADONE, the Frascati e + e − storage ring, have been carried out at C.M. energies 1.4 GeV to 2.4 GeV. The hadronic nature of the observed particles is discussed and a lower limit of 30 nbarn set for the total multiparticle cross section.

1 data table match query
Table 1

LOWER LIMIT FOR PRODUCTION OF AT LEAST TWO CHARGED HADRONS.


Initial Measurements of Z Boson Resonance Parameters in e+ e- Annihilation

Abrams, G.S. ; Adolphsen, Chris ; Aleksan, R. ; et al.
Phys.Rev.Lett. 63 (1989) 724, 1989.
Inspire Record 280007 DOI 10.17182/hepdata.20034

We have measured the mass of the Z boson to be 91.11±0.23 GeV/c2, and its width to be 1.61−0.43+0.60 GeV. If we constrain the visible width to its standard-model value, we find the partial width to invisible decay modes to be 0.62±0.23 GeV, corresponding to 3.8±1.4 neutrino species.

0 data tables match query