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Diffractive Dijet Photoproduction in ep Collisions at HERA

The H1 collaboration Aaron, F.D. ; Alexa, C. ; Andreev, V. ; et al.
Eur.Phys.J. C70 (2010) 15-37, 2010.
Inspire Record 857109 DOI 10.17182/hepdata.61487

Measurements are presented of single and double-differential dijet cross sections in diffractive photoproduction based on a data sample with an integrated luminosity of 47 pb^-1. The events are of the type ep -> eXY, where the hadronic system X contains at least two jets and is separated by a large rapidity gap from the system Y, which consists of a leading proton or low-mass proton excitation. The dijet cross sections are compared with QCD calculations at next-to-leading order and with a Monte Carlo model based on leading order matrix elements with parton showers. The measured cross sections are smaller than those obtained from the next-to-leading order calculations by a factor of about 0.6. This suppression factor has no significant dependence on the fraction x_gamma of the photon four-momentum entering the hard subprocess. Ratios of the diffractive to the inclusive dijet cross sections are measured for the first time and are compared with Monte Carlo models.

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Jets and energy flow in photon - proton collisions at HERA

The H1 collaboration Aid, S. ; Andreev, V. ; Andrieu, B. ; et al.
Z.Phys. C70 (1996) 17-30, 1996.
Inspire Record 402890 DOI 10.17182/hepdata.44935

Properties of the hadronic final state in photoproduction events with large transverse energy are studied at the electron-proton collider HERA. Distributions of the transverse energy, jets and underlying event energy are compared to $\overline{p}p$ data and QCD calculations. The comparisons show that the $\gamma p$ events can be consistently described by QCD models including -- in addition to the primary hard scattering process -- interactions between the two beam remnants. The differential jet cross sections $d\sigma/dE_T~{jet}$ and $d\sigma/d\eta~{jet}$ are measured.

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The Transverse Energy Distribution in Hadron - Lead Collisions

Akesson, T. ; Choi, Y. ; Dam, P. ; et al.
Z.Phys. C38 (1988) 397, 1988.
Inspire Record 250759 DOI 10.17182/hepdata.15655
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Diffractive photoproduction of dijets in ep collisions at HERA

The ZEUS collaboration Chekanov, Sergei ; Derrick, M. ; Magill, S. ; et al.
Eur.Phys.J. C55 (2008) 177-191, 2008.
Inspire Record 763404 DOI 10.17182/hepdata.63789

Diffractive photoproduction of dijets was measured with the ZEUS detector at the ep collider HERA using an integrated luminosity of 77.2 pb-1. The measurements were made in the kinematic range Q^2 < 1 GeV^2, 0.20 < y < 0.85 and x_pom < 0.025, where Q^2 is the photon virtuality, y is the inelasticity and x_pom is the fraction of the proton momentum taken by the diffractive exchange. The two jets with the highest transverse energy, E_T^jet, were required to satisfy E_T^jet > 7.5 and 6.5 GeV, respectively, and to lie in the pseudorapidity range -1.5 < eta^jet < 1.5. Differential cross sections were compared to perturbative QCD calculations using available parameterisations of diffractive parton distributions of the proton.

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Inclusive jet cross-section in $\bar{p}p$ collisions at $\sqrt{s} = 1.8$ TeV

The CDF collaboration Abe, F. ; Amidei, Dante E. ; Apollinari, G. ; et al.
Phys.Rev.Lett. 68 (1992) 1104-1108, 1992.
Inspire Record 319237 DOI 10.17182/hepdata.19883
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The Transverse Energy Distributions of $^{32}$S Nucleus Collisions at 200-{GeV} Per Nucleon

The HELIOS collaboration Akesson, T. ; Almehed, S. ; Angelis, A.L.S. ; et al.
Phys.Lett. B214 (1988) 295-302, 1988.
Inspire Record 265090 DOI 10.17182/hepdata.29873
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Measurement of the transverse energy flow in nucleus-nucleus collisions at 200-GeV per nucleon

The HELIOS collaboration Åkesson, T. ; Almehed, S. ; Angelis, A.L.S. ; et al.
Nucl.Phys. B353 (1991) 1-19, 1991.
Inspire Record 299861 DOI 10.17182/hepdata.33034
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Diffractive Dijet Production with a Leading Proton in $ep$ Collisions at HERA

The H1 collaboration Andreev, V. ; Baghdasaryan, A. ; Begzsuren, K. ; et al.
JHEP 1505 (2015) 056, 2015.
Inspire Record 1343110 DOI 10.17182/hepdata.73234

The cross section of the diffractive process e^+p -> e^+Xp is measured at a centre-of-mass energy of 318 GeV, where the system X contains at least two jets and the leading final state proton p is detected in the H1 Very Forward Proton Spectrometer. The measurement is performed in photoproduction with photon virtualities Q^2 <2 GeV^2 and in deep-inelastic scattering with 4 GeV^2<Q^2<80 GeV^2. The results are compared to next-to-leading order QCD calculations based on diffractive parton distribution functions as extracted from measurements of inclusive cross sections in diffractive deep-inelastic scattering.

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A Study of Deep Inelastic Hadron - Hadron Collisions with a Large Acceptance Calorimeter Trigger

The Bari-Cracow-Liverpool-Munich-Nijmegen collaboration De Marzo, C. ; De Palma, M. ; Distante, A. ; et al.
Phys.Lett. B112 (1982) 173-177, 1982.
Inspire Record 176541 DOI 10.17182/hepdata.34014
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Inclusive jet cross section in ${\bar p p}$ collisions at $\sqrt{s}=1.8$ TeV

The CDF collaboration Abe, F. ; Akimoto, H. ; Akopian, A. ; et al.
Phys.Rev.Lett. 77 (1996) 438-443, 1996.
Inspire Record 415602 DOI 10.17182/hepdata.42298

The inclusive jet differential cross section has been measured for jet transverse energies, $E_T$, from 15 to 440 GeV, in the pseudorapidity region 0.1$\leq | \eta| \leq $0.7. The results are based on 19.5 pb$~{-1}$ of data collected by the CDF collaboration at the Fermilab Tevatron collider. The data are compared with QCD predictions for various sets of parton distribution functions. The cross section for jets with $E_T>200$\ GeV is significantly higher than current predictions based on O($\alpha_s~3$) perturbative QCD calculations. Various possible explanations for the high-$E_T$\ excess are discussed.

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High-$p_T$ jets in $\bar{p}p$ collisions at $\sqrt{s} = 630$ GeV and 1800 GeV

The D0 collaboration Abbott, B. ; Abdesselam, A. ; Abolins, M. ; et al.
Phys.Rev. D64 (2001) 032003, 2001.
Inspire Record 539003 DOI 10.17182/hepdata.42946

Results are presented from analyses of jet data produced in pbarp collisions at sqrt{s} = 630 and 1800 GeV collected with the DO detector during the 1994-95 Fermilab Tevatron Collider run. We discuss details of detector calibration, and jet selection criteria in measurements of various jet production cross sections at sqrt{s} = 630 and 1800 GeV. The inclusive jet cross sections, the dijet mass spectrum, the dijet angular distributions, and the ratio of inclusive jet cross sections at sqrt{s} = 630 and 1800 GeV are compared to next-to-leading-order QCD predictions. The order alpha_s^3 calculations are in good agreement with the data. We also use the data at sqrt{s} = 1800 GeV to rule out models of quark compositeness with a contact interaction scale less than 2.2 TeV at the 95% confidence level.

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Cross section for b jet production in $\bar{p}p$ collisions at $\sqrt{s} = 1.8$ TeV

The D0 collaboration Abbott, B. ; Abolins, M. ; Abramov, V. ; et al.
Phys.Rev.Lett. 85 (2000) 5068-5073, 2000.
Inspire Record 531669 DOI 10.17182/hepdata.42975

Bottom quark production in pbar-p collisions at sqrt(s)=1.8 TeV is studied with 5 inverse picobarns of data collected in 1995 by the DO detector at the Fermilab Tevatron Collider. The differential production cross section for b jets in the central rapidity region (|y(b)| < 1) as a function of jet transverse energy is extracted from a muon-tagged jet sample. Within experimental and theoretical uncertainties, DO results are found to be higher than, but compatible with, next-to-leading-order QCD predictions.

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Inclusive jet production in photon-photon collisions at $\sqrt{s}$ = 130-GeV and 136-GeV

The OPAL collaboration Ackerstaff, K. ; Alexander, G. ; Allison, John ; et al.
Z.Phys. C73 (1997) 433-442, 1997.
Inspire Record 424635 DOI 10.17182/hepdata.47713
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Study of the energy flow in sulphur and oxygen nucleus collisions at 60-GeV/nucleon and 200-GeV/nucleon

The NA35 collaboration Baechler, J. ; Bartke, J. ; Bialkowska, H. ; et al.
Z.Phys. C52 (1991) 239-263, 1991.
Inspire Record 323583 DOI 10.17182/hepdata.1434

We report on a systematic study of midrapidity transverse energy production and forward energy flow in interactions of16O and32S projectiles with S, Cu, Ag and Au targets at 60 and 200 GeV/nucleon. The variation of the shape of theET distributions with target and projectile mass can be understood from collision geometry. AverageET values determined for central collisions show an increasing stopping power for heavier target nuclei. A higher relative stopping is observed at 60 GeV/nucleon than at 200 GeV/nucleon. Bjorken estimates of the energy density reach approximately 3 GeV/fm3 in highET events at 200 GeV/nucleon with16O and32S projectiles. The systematics of the data and the shapes ofET and pseudorapidity distributions are well described by the Lund model Fritiof.

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The Transverse Energy Distribution in $^{16}$O - Nucleus Collisions at 60-{GeV} and 200-{GeV} Per Nucleon

The HELIOS collaboration Akesson, T. ; Almehed, S. ; Angelis, A.L.S. ; et al.
Z.Phys. C38 (1988) 383, 1988.
Inspire Record 250767 DOI 10.17182/hepdata.15648
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DIJET PRODUCTION CROSS-SECTION AND FRAGMENTATION OF JETS PRODUCED IN P P COLLISIONS AT S**(1/2) = 63-GEV

The AXIAL FIELD SPECTROMETER collaboration Akesson, T. ; Albrow, M.G. ; Almehed, S. ; et al.
Z.Phys. C30 (1986) 27-43, 1986.
Inspire Record 221571 DOI 10.17182/hepdata.16017

We present stdies of events triggered on two high-pT jets, produced inpp collisions at the CERN Intersecting Storage Rings (ISR) at\(\sqrt s \)=63 GeV, using a large solid angle calorimeter. The cross-section for producing two jets is measured in the dijet mass range 17–50 GeV/c2. A high-statistics sample of dijet events, where each jet has transverse energy above 10 GeV, is used to study the structure of jets and the associated event. We find the longitudinal fragmentation function to be similar to that of jets emerging frome+e− collisions but considerably harder than that observed at the Super Proton Synchrotron (SPS)\(p\bar p\) Collider. A steepening of the fragmentation function is observed when increasing the jet energy. Studies of the charge distribution in jets show that these predominantly originate from fragmenting valence quarks. The transverse energy and particle flows are presented as functions of the azimuthal distance from the jet axis.

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Measurement of the inclusive jet cross-section in $\bar{p}p$ collisions at $\sqrt{s} = 1.8$ TeV

The CDF collaboration Abe, F. ; Amidei, D. ; Apollinari, G. ; et al.
Phys.Rev.Lett. 62 (1989) 613, 1989.
Inspire Record 267999 DOI 10.17182/hepdata.20032
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J / psi and muon pair cross-sections in proton nucleus and nucleus-nucleus collisions at 200-GeV per nucleon

Baglin, C. ; Baldisseri, A. ; Bussiere, A. ; et al.
Phys.Lett. B270 (1991) 105-110, 1991.
Inspire Record 328409 DOI 10.17182/hepdata.29301
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Comparison of jet production in $\bar{p}p$ collisions at $\sqrt{s} = 546$ GeV and 1800 GeV

The CDF collaboration Abe, F. ; Amidei, Dante E. ; Anway, Carol E. ; et al.
Phys.Rev.Lett. 70 (1993) 1376-1380, 1993.
Inspire Record 341846 DOI 10.17182/hepdata.19770
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Dijet production in photon-photon collisions at s(ee)**(1/2) from 189-GeV to 209-GeV

The OPAL collaboration
Eur.Phys.J. C31 (2003) 307-325, 2003.
Inspire Record 611415 DOI 10.17182/hepdata.49662

Di-jet producion is studied in collisions of quasi-real photons at e+e- centre- of-mass energies sqrt(s)ee from 189 to 209 GeV at LEP. The data were collected with the OPAL detector. Jets are reconstructed using an inclusive k_t clustering algorithm for all cross-section measurements presented. A cone jet algorithm is used in addition to study the different structure of the jets resulting from either of the algorithms. The inclusive di-jet cross-section is measured as a function of the mean transverse energy Etm(jet) of the two leading jets, and as a functiuon of the estimated fraction of the photon momentum carried by the parton entering the hard sub-process, xg, for different regions of Etm (jet). Angular distribution in di-jet events are measured and used to demonstrate the dominance of quark and gluon initiated processes in different regions of phase space. Furthermore the inclusive di-jet cross-section as a function of |eta(jet)| and |delta eta (jet)| is presented where eta(jet) is the jet pseudo-rapidity. Different regions of the xg+ -xg- -space are explored to study and control the influence of an underlying event. The results are compared to next-to-leading order perturbative QCD calculations and to the predictions of the leading order Monte Carlo generator PYTHIA.

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Measurement of the cross section for direct-photon production in association with a heavy quark in $p\bar{p}$ collisions at $\sqrt{s}$ = 1.96 TeV

The CDF collaboration Aaltonen, T. ; Amerio, S. ; Amidei, D. ; et al.
Phys.Rev.Lett. 111 (2013) 042003, 2013.
Inspire Record 1225278 DOI 10.17182/hepdata.61735

We report on a measurement of the cross section for direct-photon production in association with a heavy quark using the full data set of $\sqrt{s}=1.96$ TeV proton-antiproton collisions corresponding to 9.1 fb$^{-1}$ of integrated luminosity collected by the CDF II detector at the Fermilab Tevatron. The measurements are performed as a function of the photon transverse momentum, covering photon transverse momentum between 30 and 300 GeV, photon rapidities $|y^{\gamma}|<1.0$, heavy-quark-jet transverse momentum $p_{T}^{jet}>20$ GeV, and jet rapidities $|y^{jet}|<1.5$. The results are compared with several theoretical predictions.

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High-$E_{\rm T}$ isolated-photon plus jets production in $pp$ collisions at $\sqrt s=$ 8 TeV with the ATLAS detector

The ATLAS collaboration Aaboud, Morad ; Aad, Georges ; Abbott, Brad ; et al.
Nucl.Phys. B918 (2017) 257-316, 2017.
Inspire Record 1499475 DOI 10.17182/hepdata.79948

The dynamics of isolated-photon plus one-, two- and three-jet production in pp collisions at a centre-of-mass energy of 8 TeV are studied with the ATLAS detector at the LHC using a data set with an integrated luminosity of 20.2 fb−1 . Measurements of isolated-photon plus jets cross sections are presented as functions of the photon and jet transverse momenta. The cross sections as functions of the azimuthal angle between the photon and the jets, the azimuthal angle between the jets, the photon–jet invariant mass and the scattering angle in the photon–jet centre-of-mass system are presented. The pattern of QCD radiation around the photon and the leading jet is investigated by measuring jet production in an annular region centred on each object; enhancements are observed around the leading jet with respect to the photon in the directions towards the beams. The experimental measurements are compared to several different theoretical calculations, and overall a good description of the data is found.

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A Study of the associated production of photons and b-quark jets in p p-bar collisions at s**(1/2) = 1.96-TeV

The CDF collaboration Aaltonen, T. ; Adelman, J. ; Alvarez Gonzalez, B. ; et al.
Phys.Rev. D81 (2010) 052006, 2010.
Inspire Record 840503 DOI 10.17182/hepdata.64152

The cross section for photon production in association with at least one jet containing a $b$-quark hadron has been measured in proton antiproton collisions at $\sqrt{s}=1.96$ TeV. The analysis uses a data sample corresponding to an integrated luminosity of 340 pb$^{-1}$ collected with the CDF II detector. Both the differential cross section as a function of photon transverse energy $E_T^{\gamma}$, $d \sigma$($p \overline{p} \to \gamma + \geq 1 b$-jet)/$d E_T^{\gamma}$ and the total cross section $\sigma$($p \overline{p} \to \gamma + \geq 1 b$-jet/ $E_T^{\gamma}> 20$ GeV) are measured. Comparisons to a next-to-leading order prediction of the process are presented.

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