scholarly journals Exclusive photoproduction of a γ ρ pair with a large invariant mass

2017 ◽  
Vol 2017 (2) ◽  
Author(s):  
R. Boussarie ◽  
B. Pire ◽  
L. Szymanowski ◽  
S. Wallon
Keyword(s):  
Transverse Momentum ◽  
Invariant Mass ◽  
Cross Sections ◽  
Differential Cross ◽  
Scattering Amplitude ◽  
Differential Cross Sections ◽  
Leading Order ◽  
Collinear Factorization

Abstract Exclusive photoproduction of a γ ρ pair in the kinematics where the pair has a large invariant mass and the final nucleon has a small transverse momentum is described in the collinear factorization framework. The scattering amplitude is calculated at leading order in α s and the differential cross sections for the process where the ρ−meson is either longitudinally or transversely polarized are estimated in the kinematics of the JLab 12-GeV experiments.

HADRON SPIN-FLIP AMPLITUDE AND SLOPE OF DIFFERENTIAL CROSS-SECTIONS

1999 ◽  
Vol 14 (03) ◽  
pp. 223-230 ◽  
Author(s):  
O. V. SELYUGIN
Keyword(s):  
Experimental Data ◽  
Cross Sections ◽  
Differential Cross ◽  
Scattering Amplitude ◽  
Previous Analysis ◽  
Differential Cross Sections ◽  
Spin Flip ◽  
Flip Amplitude

A possibility to obtain restrictions of the magnitude of the elastic spin-flip hadron scattering amplitude from accurately measured experimental data on the differential cross-sections of elastic hadron–hadron scattering is shown. Appropriate estimations confirm the previous analysis of experimental data at [Formula: see text] GeV and a probable contribution of the hadron spin-flip amplitude.

An experimental investigation of small angle photon elastic scattering

1979 ◽  
Vol 57 (3) ◽  
pp. 343-352 ◽  
Author(s):  
N. Ramanathan ◽  
T. J. Kennett ◽  
W. V. Prestwich
Keyword(s):  
Experimental Investigation ◽  
Elastic Scattering ◽  
Cross Sections ◽  
Small Angle ◽  
Differential Cross ◽  
Bound States ◽  
Scattering Amplitude ◽  
Form Factors ◽  
Differential Cross Sections

The differential cross sections for photon elastic scattering have been determined for targets of Cu, Cd, Ta, and Pb, at angles of 2.4, 3.5, 5.1., 6.0, 8.0, and 10.0° and incident energies of 244.7, 344.3, 443.9, 778.9, 964.0, 1085.8, 1112.0, 1274.2, and 1408.0 keV. The data indicate that presently calculated form factors may be too large, and suggest that intermediate bound states may influence the scattering amplitude.

scholarly journals Observation of Odderon effects at LHC energies: a real extended Bialas–Bzdak model study

2021 ◽  
Vol 81 (7) ◽  
Author(s):  
T. Csörgő ◽  
I. Szanyi
Keyword(s):  
Differential Cross Section ◽  
Cross Section ◽  
Cross Sections ◽  
Differential Cross ◽  
Scattering Amplitude ◽  
Proton Collision ◽  
Differential Cross Sections ◽  
Proton Antiproton ◽  
Proton Proton ◽  
Elastic Proton

AbstractThe unitarily extended Bialas–Bzdak model of elastic proton–proton scattering is applied, without modifications, to describe the differential cross-section of elastic proton–antiproton collisions in the TeV energy range, and to extrapolate these differential cross-sections to LHC energies. In this model-dependent study we find that the differential cross-sections of elastic proton–proton collision data at 2.76 and 7 TeV energies differ significantly from the differential cross-section of elastic proton–antiproton collisions extrapolated to these energies. The elastic proton–proton differential cross-sections, extrapolated to 1.96 TeV energy with the help of this extended Bialas–Bzdak model do not differ significantly from that of elastic proton–antiproton collisions, within the theoretical errors of the extrapolation. Taken together these results provide a model-dependent, but statistically significant evidence for a crossing-odd component of the elastic scattering amplitude at the at least 7.08 sigma level. From the reconstructed Odderon and Pomeron amplitudes, we determine the $$\sqrt{s}$$ s dependence of the corresponding total and differential cross-sections.

scholarly journals Measurement of the production cross section of pairs of isolated photons in pp collisions at 13 TeV with the ATLAS detector

2021 ◽  
Vol 2021 (11) ◽  
Author(s):  
◽  
G. Aad ◽  
B. Abbott ◽  
D. C. Abbott ◽  
A. Abed Abud ◽  
...  
Keyword(s):  
Transverse Momentum ◽  
Cross Sections ◽  
Differential Cross ◽  
Production Cross ◽  
Atlas Detector ◽  
Differential Cross Sections ◽  
Proton Proton ◽  
Theoretical Predictions ◽  
Fixed Order ◽  
Isolated Photons

Abstract A measurement of prompt photon-pair production in proton-proton collisions at $$ \sqrt{s} $$ s = 13 TeV is presented. The data were recorded by the ATLAS detector at the LHC with an integrated luminosity of 139 fb−1. Events with two photons in the well-instrumented region of the detector are selected. The photons are required to be isolated and have a transverse momentum of $$ {p}_{\mathrm{T}{,}_{\gamma 1(2)}} $$ p T , γ 1 2 > 40 (30) GeV for the leading (sub-leading) photon. The differential cross sections as functions of several observables for the diphoton system are measured and compared with theoretical predictions from state-of-the-art Monte Carlo and fixed-order calculations. The QCD predictions from next-to-next-to-leading-order calculations and multi-leg merged calculations are able to describe the measured integrated and differential cross sections within uncertainties, whereas lower-order calculations show significant deviations, demonstrating that higher-order perturbative QCD corrections are crucial for this process. The resummed predictions with parton showers additionally provide an excellent description of the low transverse-momentum regime of the diphoton system.

scholarly journals High Order QCD Predictions for Inclusive Production ofWBosons inppCollisions ats=13 TeV

2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Hasan Ogul ◽  
Kamuran Dilsiz ◽  
Emrah Tiras ◽  
Ping Tan ◽  
Yasar Onel ◽  
...  
Keyword(s):  
Perturbative Qcd ◽  
Cross Section ◽  
Cross Sections ◽  
Differential Cross ◽  
Charge Asymmetry ◽  
Inclusive Production ◽  
Differential Cross Sections ◽  
Leading Order ◽  
Central Values ◽  
Lepton Charge

Predictions of fiducial cross sections, differential cross sections, and lepton charge asymmetry are presented for the production ofW±bosons with leptonic decay up to next-to-next-to-leading order (NNLO) in perturbative QCD. Differential cross sections ofW±bosons andWboson lepton charge asymmetry are computed as a function of lepton pseudorapidity for a defined fiducial region inppcollisions ats=13 TeV. Numerical results of fiducialW±cross section predictions are presented with the latest modern PDF models at next-to-leading order (NLO) and NNLO. It is found that the CT14 and NNPDF 3.0 predictions with NNLO QCD corrections are about 4% higher than the NLO CT14 and NNPDF 3.0 predictions while MMHT 2014 predictions with NLO QCD corrections are smaller than its NNLO QCD predictions by approximately 6%. In addition, the NNLO QCD corrections reduce the scale variation uncertainty on the cross section by a factor of 3.5. The prediction of central values and considered uncertainties are obtained using FEWZ 3.1 program.

Sign in / Sign up

Export Citation Format

Share Document