High precision measurement of Compton scattering in the 5 GeV region

P Ambrozewicz,A Shahinyan,V Matveev,D Rimal,D Dutta,R Miskimen,X Li,R Pedroni,E Pasyuk,V Gyurjyan,A Ahmidouch,B Morrison,E Clinton,P Collins,Y Zhang,V Baturin,A Kolarkar,A Teymurazyan,S Danagoulian,M Gabrielyan,G Fedotov,M Kubantsev,L Gan,M Payen,C Salgado,D Dale,P Kingsberry,S Overby,W Stephens,R Minehart,M Khandaker,L Ye,D Protopopescu,A Sitnikov,I Larin,L Guo,M Konchatnyi,M Levillain,S Stepanyan,A Dolgolenko,W Korsch,R Demirchyan,N Gevorkyan,W Phelps,B Zihlmann,L Benton,A Deur,D Kashy,J Feng,Y Prok,I Nakagawa,A Glamazdin,A Kubarovsky,A Evdokimov,S Taylor,D Mcnulty,O Kosinov,V Kubarovsky,S Kowalski,K Park,D Lawrence,S Mtingwa,A Gasparian,V D Burkert ,A M Bernstein ,K.a Hardy ,A Micherdzińska ,Gao H ,Heon Kang ,D P Weygand ,Shiwei Zhou ,B A Mecking ,Dmitry Romanov ,P P Martel ,A N Vasiliev ,H Y Lu ,V N Goryachev ,A Yu Korchin ,G.b Dzyubenko ,P L Cole ,D I Sober ,Brian D Milbrath ,B G Ritchie ,F J Klein ,Jonathan G Underwood ,M M Ito ,Jianhui He ,G.v Davidenko ,V.e Vishnyakov ,V V Tarasov ,E L Isupov ,M H Wood ,В В Мочалов ,L L ,S R Gevorkyan ,L L Jiang ,Keith Baker

doi:10.1016/j.physletb.2019.134884

Abstract

The cross section of atomic electron Compton scattering γ+e→γ′+e′ was measured in the 4.400–5.475 GeV photon beam energy region by the PrimEx collaboration at Jefferson Lab with an accuracy of 2.6% and less. The results are consistent with theoretical predictions that include next-to-leading order radiative corrections. The measurements provide the first high precision test of this elementary QED process at beam energies greater than 0.1 GeV.

Highlights

Quantum electrodynamics (QED) is one of the most successful theories in modern physics; and the Compton scattering of photons by free electrons γ + e → γ + e is the simplest and the most elementary pure QED process
The cross section of atomic electron Compton scattering γ + e → γ + e was measured in the 4.400–5.475 GeV photon beam energy region by the PrimEx collaboration at Jefferson Lab with an accuracy of 2.6% and less
We conclude that this measurement constitutes the first confirmation that the Quantum electrodynamics (QED) next-to-leading order prediction correctly describes this fundamental process up to a photon energy, Eγ, of 5.5 GeV within our experimental precision

Summary

Introduction

Quantum electrodynamics (QED) is one of the most successful theories in modern physics; and the Compton scattering of photons by free electrons γ + e → γ + e is the simplest and the most elementary pure QED process. Higher-order contributions arising from the interference between the leading order single Compton scattering amplitude and the radiative and double Compton scattering amplitudes were calculated in the 1950s [3, 4]. They were subsequently re-evaluated in the 60s and early 70s to make them amenable for calculation using modern computational techniques [5]-[7]. Corrections to the leading order Compton total cross section at the level of a few percent are predicted for beam energies above 0.1 GeV [6], the next-to-leading order (NLO) corrections are important when studying Compton scattering at these energies

Methods

Results

Conclusion