The Impact of Single Top Data on CT14nnlo PDFs
- PDF / 722,303 Bytes
- 9 Pages / 439.642 x 666.49 pts Page_size
- 116 Downloads / 179 Views
The Impact of Single Top Data on CT14nnlo PDFs Alim Ablat1 · Sayipjamal Dulat1
· Reyima Rashidin1 · Alim Ruzi2 · Nijat Yalkun3,4
Received: 1 December 2019 / Accepted: 21 April 2020 / © Springer Science+Business Media, LLC, part of Springer Nature 2020
Abstract In this paper we study the impact of ATLAS 8 TeV t-channel single top quark production data on CT14nnlo PDFs. First, we calculate the total cross section, cross section ratio, differential cross section, and normalized differential cross section as a function of transverse momentum pT and rapidity y, at next-to-leading order QCD by MadGraph using CT14nnlo PDFs. And then we update CT14nnlo PDFs and observables by applying Error PDF Updating method. We find that down quark PDF increased roughly about 3% in 10−4 < x < 4 × 10−3 range at Q = 1.3 GeV, when weight factor equals to six. Furthermore, for data and theory comparison, we get slightly better agreement after updating observables. Keywords Single top quark production · Update PDFs
1 Introduction Parton distribution functions (PDFs) [1–9] are very important ingredients for theoretical predictions at hadron colliders such as Large Hadron Collider (LHC) and Tevatron collider as well as other hadron scattering facilities like lepton-hadron Colliders. And it also plays a significant role for both precision measurements and discovery of possible new physics beyond the SM [10–13]. The PDFs are non-perturbative and therefore at present it can not be calculated from first principle at a low momentum transfer scale Q0 . The general way to obtain PDFs is a global analysis of experimental data from various high energy scattering, like Deep Inelastic Scattering (DIS) at lepton-hadron colliders and proton-proton collision at LHC as well as proton-antiproton collision at the Fermilab Tevatron. By now there are large number of new LHC data have been available and it is very important for constraining PDFs. Currently, the common and complete method for obtaining more precise PDFs is to include Sayipjamal Dulat
[email protected] 1
School of Physics Science and Technology, Xinjiang University, Urumqi, Xinjiang, 830046, China
2
School of Physics, Peking University, Beijing, 100871, China
3
Institute of theoretical Physics, Chinese Academy of Science, Beijing, 100190, China
4
University of Chinese Academy of Sciences, Beijing, 100049, China
International Journal of Theoretical Physics
new experimental data within the QCD global analysis package and redo the global fitting. It means that one should include the new data and old data which are already in the older PDFs, and do the full global analysis to obtain new best fit PDFs and corresponding error sets. However, redoing the QCD global analysis of PDFs is a very time consuming process. This consideration motivated us to explore different methods that overcome the difficulties that we mentioned above. In this paper, we analyze the impact of t-channel single top quark production cross section data on CT14nnlo PDFs [1] by using error PDF Updating Method Package
Data Loading...
