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Measurements of Higgs boson properties in the diphoton decay channel with 36 fb$^{-1}$ of $pp$ collision data at $\sqrt{s} = 13$ TeV with the ATLAS detector

The ATLAS collaboration Aaboud, Morad ; Aad, Georges ; Abbott, Brad ; et al.
Phys.Rev.D 98 (2018) 052005, 2018.
Inspire Record 1654582 DOI 10.17182/hepdata.83417

Properties of the Higgs boson are measured in the two-photon final state using 36.1 fb$^{-1}$ of proton-proton collision data recorded at $\sqrt{s} = 13$ TeV by the ATLAS experiment at the Large Hadron Collider. Cross-section measurements for the production of a Higgs boson through gluon-gluon fusion, vector-boson fusion, and in association with a vector bosonor a top-quark pair are reported. The signal strength, defined as the ratio of the observed to the expected signal yield, is measured for each of these production processes as well as inclusively. The global signal strength measurement of $0.99 \pm 0.14$ improves on the precision of the ATLAS measurement at $\sqrt{s} = 7$ and 8 TeV by a factor of two. Measurements of gluon-gluon fusion and vector-boson fusion productions yield signal strengths compatible with the Standard Model prediction. Measurements of simplified template cross sections, designed to quantify the different Higgs boson production processes in specific regions of phase space, are reported. The cross section for the production of the Higgs boson decaying to two isolated photons in a fiducial region closely matching the experimental selection of the photons is measured to be $55 \pm 10$ fb, which is in good agreement with the Standard Model prediction of $64 \pm 2$ fb. Furthermore, cross sections in fiducial regions enriched in Higgs boson production in vector-boson fusion or in association with large missing transverse momentum, leptons or top-quark pairs are reported. Differential and double-differential measurements are performed for several variables related to the diphoton kinematics as well as the kinematics and multiplicity of the jets produced in association with a Higgs boson. No significant deviations from a wide array of Standard Model predictions are observed.

39 data tables

Measured differential cross section with associated uncertainties as a function of PT(2GAMMA). Each systematic uncertainty sources is fully uncorrelated with the other sources and fully correlated across bins, except for the background modelling systematics for which an uncorrelated treatment across bins is more appropriate.

Measured differential cross section with associated uncertainties as a function of YRAP(2GAMMA). Each systematic uncertainty sources is fully uncorrelated with the other sources and fully correlated across bins, except for the background modelling systematics for which an uncorrelated treatment across bins is more appropriate.

Measured differential cross section with associated uncertainties as a function of PTTHRUST(2GAMMA). Each systematic uncertainty sources is fully uncorrelated with the other sources and fully correlated across bins, except for the background modelling systematics for which an uncorrelated treatment across bins is more appropriate.

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Jet and underlying event properties as a function of particle multiplicity in proton-proton collisions at sqrt(s) = 7 TeV

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
Eur.Phys.J.C 73 (2013) 2674, 2013.
Inspire Record 1261026 DOI 10.17182/hepdata.68128

Characteristics of multi-particle production in proton-proton collisions at $\sqrt{s}$=7 TeV are studied as a function of the charged-particle multiplicity, $N_{ch}$. The produced particles are separated into two classes: those belonging to jets and those belonging to the underlying event. Charged particles are measured with pseudorapidity |η|<2.4 and transverse momentum $p_T$ > 0.25 GeV/c. Jets are reconstructed from charged-particles only and required to have $p_T$ > 5 GeV/c. The distributions of jet $p_T$, average $p_T$ of charged particles belonging to the underlying event or to jets, jet rates, and jet shapes are presented as functions of $N_{ch}$ and compared to the predictions of the PYTHIA and HERWIG event generators. Predictions without multi-parton interactions fail completely to describe the $N_{ch}$-dependence observed in the data. For increasing $N_{ch}$, PYTHIA systematically predicts higher jet rates and harder $p_T$ spectra than seen in the data, whereas HERWIG shows the opposite trends. At the highest multiplicity, the data–model agreement is worse for most observables, indicating the need for further tuning and/or new model ingredients.

17 data tables

Mean $p_T$, all charged particles.

Mean $p_T$, UE charged particles.

Mean $p_T$, in-jet charged particles.

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Shape, transverse size, and charged hadron multiplicity of jets in pp collisions at 7 TeV

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
JHEP 06 (2012) 160, 2012.
Inspire Record 1111014 DOI 10.17182/hepdata.70063

Measurements of jet characteristics from inclusive jet production in proton-proton collisions at a centre-of-mass energy of 7 TeV are presented. The data sample was collected with the CMS detector at the LHC during 2010 and corresponds to an integrated luminosity of 36 inverse picobarns. The mean charged hadron multiplicity, the differential and integral jet shape distributions, and two independent moments of the shape distributions are measured as functions of the jet transverse momentum for jets reconstructed with the anti-kT algorithm. The measured observables are corrected to the particle level and compared with predictions from various QCD Monte Carlo generators.

128 data tables

The measured differential jet shape $\rho(r)$ for jets with 20 GeV $< p_{\mathrm{T}} <$ 25 GeV and 0 <|y|< 0.5. The CF in the table refers to unfolding correction factor from {\sc pythia6} Tune Z2. The systematic uncertainties from different sources, jet energy scale (JES), unfolding, and single particle response (SPR), are also presented.

The measured differential jet shape $\rho(r)$ for jets with 25 GeV $< p_{\mathrm{T}} <$ 30 GeV and 0 <|y|< 0.5. The CF in the table refers to unfolding correction factor from {\sc pythia6} Tune Z2. The systematic uncertainties from different sources, jet energy scale (JES), unfolding, and single particle response (SPR), are also presented.

The measured differential jet shape $\rho(r)$ for jets with 30 GeV $< p_{\mathrm{T}} <$ 40 GeV and 0 <|y|< 0.5. The CF in the table refers to unfolding correction factor from {\sc pythia6} Tune Z2. The systematic uncertainties from different sources, jet energy scale (JES), unfolding, and single particle response (SPR), are also presented.

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Test of spin dependence in charm-quark fragmentation to D*.

The TPC/Two-Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Avery, R.E. ; et al.
Phys.Rev.D 43 (1991) 29-33, 1991.
Inspire Record 316132 DOI 10.17182/hepdata.22830

We have measured the polarization of D*, the energy dependence of the polarization, and the spin-density matrix of D* in e+e− annihilation at a center-of-mass energy of 29 GeV using the Time Projection Chamber detector at the SLAC storage ring PEP. In 147 pb−1 of data we see no strong evidence for polarization, alignment, or final-state interactions in this fragmentation process.

2 data tables

Polarization is the factor alpha(z) in the expression d width (D*-->D pi)/domega = C(1+alpha(z)cos(theta)**2).

Spin density matrices for D* --> D0 pi+.


Phi Meson Production in 3.75-GeV/c pi+ p Interactions

Gidal, G. ; Michael, W. ; Trilling, G. ; et al.
Phys.Rev.D 17 (1978) 1256, 1978.
Inspire Record 5868 DOI 10.17182/hepdata.31764

The production of φ mesions is studied in the reaction π+p→π+p K+K− and π+→π+p K0K¯0 at 3.75 GeV/c. A large isotropic component is seen in the production angular distribution for the reaction π+p→π+pφ. The cross sections for the φπ+p and φΔ++ final states are compared with the cross sections for ωπ+p and ωΔ++ at the same momentum.

3 data tables

NORMALIZED TO THE CROSS SECTION FOR PI+ P --> PI+ P PI+ PI-.

No description provided.

No description provided.


Meson Production by Delta Exchange in pi- p Interactions at 4-GeV/c

Scharre, D.L. ; Chapman, J.W. ; Ely, R.P. ; et al.
Phys.Rev.D 17 (1978) 2853, 1978.
Inspire Record 121388 DOI 10.17182/hepdata.24432

A streamer-chamber spectrometer is triggered by fast forward protons from 4-GeV/c π−p interactions at the Bevatron. Meson-resonance production in the backward, Iu=32 exchange reactions π−p→pM− are studied, where M− refers to π−, ρ−, A1−, A2−, and B−. Elastic scattering and ρ− production are observed and discussed in detail. No backward A1−, A2−, or B− production is observed at the level of approximately 5 βb.

5 data tables

Axis error includes +- 15/15 contribution.

No description provided.

Axis error includes +- 15/15 contribution.

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Omega Production in the Reaction pi- p --> pi+ pi- pi0 n at 8-GeV/c and 12-GeV/c

Dowell, J.D. ; Garvey, J. ; Jobes, M. ; et al.
Nucl.Phys.B 108 (1976) 30-44, 1976.
Inspire Record 100856 DOI 10.17182/hepdata.35781

The reaction π − p → ω n has been studied at 8 and 12 GeV / c incident momenta with the CERN Omega spectrometer using a neutron time of flight trigger. The differential cross sections and the ω-decay density matrix elements are presented as functions of the momentum transfer squared − t in the range of 0.02 to 0.80 GeV 2 . The data are used to evaluate the intercept and slope of both the natural and unnatural parity exchange trajectories. Regge exchange amplitude factorisation tests involving the reaction π N → ω N are investigated.

3 data tables

No description provided.

'FIT'.

'FIT'.


Study of the A2: An Analysis of the Reaction pi- p --> eta pi- p and a Missing Mass Spectrum at 6-GeV/c

Underwood, D. ; Conforto, G. ; Kramer, M.A. ; et al.
Phys.Rev.D 11 (1975) 2345-2366, 1975.
Inspire Record 103078 DOI 10.17182/hepdata.24888

The reaction π−p→X−p, X−→ηπ−, η→γγ has been studied in an optical spark-chamber experiment at the Argonne ZGS (Zero Gradient Synchrotron) at a beam momentum of 6.0 GeV/c and with 0.27≤|t|≤0.42 (GeV/c)2. The ηπ mass spectrum contains about 1400 events in the mass range 0.80<M(ηπ)<1.55 GeV/c2, and is dominated by approximately 1000 events of the type A2−→ηπ−. No structure is discernible within the A2 mass spectrum for an experimental resolution of 7.1 MeV/c2 [16.7 MeV/c2 FWHM (full width at half maximum)]. A single D-wave Breit-Wigner distribution fits the data with a high confidence level, yielding for the A2 the parameters M0=1.323±0.003 GeV/c2 and Γ0=0.108±0.009 GeV/c2. The angular distribution of the decay A2−→ηπ− is analyzed and the resultant density matrix elements have the values ρ11=0.45±0.02, ρ1−1=0.45±0.04, and ρ00=0.09±0.04. All other elements are consistent with zero. Finally, the missing-mass spectrum in the region of the A2 is presented. A signal of 230 events above background per 5-MeV/c2 interval is observed at the A2 peak, with a signal to background ratio of greater than 1:1. A single D-wave Breit-Wigner distribution together with a quadratic background fits the data well, with the parameters for the A2 being M0=1.324±0.003 GeV/c2 and Γ0=0.104±0.009 GeV/c2. Both A2 mass spectra are incompatible with the dipole shape.

2 data tables

No description provided.

THIS FIT ASSUMES ALL OTHER DENSITY MATRIX ELEMENTS (RHO(2M) AND RE(RHO(10))) ARE ZERO SINCE THEY ARE QUITE CONSISTENT WITH ZERO IN A FULL FIT. QUOTED ERRORS INCLUDE SYSTEMATIC ERRORS, WHILE STATISTICAL FITTING ERRORS ARE SHOWN SEPARATELY.


Amplitude analysis from decay correlations - application to pi- p ---> k*(0) lambda at 3.9 gev/c

Abramovich, M. ; Irving, A.C. ; Martin, Alan D. ; et al.
Phys.Lett.B 39 (1972) 353-357, 1972.
Inspire Record 75784 DOI 10.17182/hepdata.28306

Decay correlation data for π − p → K ∗ Λ at 3.9 GeV /c are analyzed to determine the amplitude structure. We emphasize combinations of observables invariant under rotations between s and t channel frames.

1 data table

No description provided.


Reaction pi+ p ---> rho+ p at 2.67 gev/c - a study of isoscalar exchanges

Michael, W. ; Gidal, G. ;
Phys.Rev.Lett. 28 (1972) 1475-1479, 1972.
Inspire Record 75483 DOI 10.17182/hepdata.21443

Results are presented of a study of the reaction π+p→ρ+p at 2.67 GeV/c incident π+ momentum. The contributions due to given spin-parity exchanges are isolated; and, by combining these results with those of a similar π− experiment, the It=0 component of each series is separated. The ω (I=0, JPG=1−−) exchange contribution shows a pronounced dip at −t=0.4 (GeV/c)2. Evidence is presented for the exchange of a state of minimum quantum numbers, H (I=0, JPG=1+−).

6 data tables

No description provided.

No description provided.

No description provided.

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