arXiv subjects

Chien-Peng Yuan

Publications and source records attributed to Chien-Peng Yuan.

5 recordsLinked to original sources

arXiv2026

Further Reduction of the PDF Uncertainty in the High-Mass Drell-Yan Spectrum Utilizing Neutral and Charged Current Inputs

Uncertainties in the parametrization of Parton Distribution Functions are a serious limiting systematic uncertainty in Large Hadron Collider searches for Beyond the Standard Model physics. This is especially true for measurements at high scales induced by quark and anti-quark collisions, where Drell-Yan continuum backgrounds are dominant. In Phys. Rev. D99, 054004 (2019) we presented a unique strategy for improving uncertainties using neutral current Drell-Yan backgrounds and here we update that strategy and include charged current Drell-Yan final states in the program and demonstrate significant improvements. Through a judicious selection of measurable kinematical quantities can reduce the assigned systematic PDF uncertainties by significant factors in limit-setting or discovery for neutral and charged, high mass Intermediate Vector Bosons. This approach will be take advantage of the huge statistical precision of future High Luminosity, Large Hadron Collider Standard Model datasets and could also improve uncertainties in the high statistics results from LHC Run 3.

hep-ph↗

arXiv2023

Probing Parton distribution functions at large x via Drell-Yan Forward-Backward Asymmetry

The forward-backward asymmetry of the Drell-Yan process in dilepton decays at high invariant masses can be used to probe the parton distribution functions at large x. The behavior of three modern PDF sets (CT18NNLO, MSHT20, and NNPDF4.0) are compared, and updated under various scenarios via ePump using proton-proton collision pseudo-data generated at sqrt(s) = 13 TeV with 3000 fb^{-1} of integrated luminosity.

hep-ph↗

arXiv2019

A New Method for Reducing PDF Uncertainties in the High-Mass Drell-Yan Spectrum

Uncertainties in the parametrization of Parton Distribution Functions (PDFs) are becoming a serious limiting systematic uncertainty in Large Hadron Collider (LHC) searches for Beyond the Standard Model physics. This is especially true for measurements at high scales induced by quark and anti-quark collisions, where Drell-Yan continuum backgrounds are dominant. Tools are recently available which enable exploration of PDF fitting strategies and emulate the effects of new data in a future global fit. ePump is such a tool and it is shown that judicious selection of measurable kinematical quantities can reduce the assigned systematic PDF uncertainties by significant factors. This will be made possible by the huge statistical precision of future LHC Standard Model datasets.

hep-ex↗

arXiv2015

Higgs self-coupling in the MSSM and NMSSM after the LHC Run 1

Measuring the Higgs self-coupling is one of the crucial physics goals at the LHC Run-2 and other future colliders. In this work, we attempt to figure out the size of SUSY effects on the trilinear self-coupling of the 125 GeV Higgs boson in the MSSM and NMSSM after the LHC Run-1. Taking account of current experimental constraints, such as the Higgs data, flavor constraints, electroweak precision observables and dark matter detections, we obtain the observations: (1) In the MSSM, the ratio of $λ^{MSSM}_{3h}/λ^{SM}_{3h}$ has been tightly constrained by the LHC data, which can be only slightly smaller than 1 and minimally reach 97\%; (2) In the NMSSM with $λ<0.7$, a sizable reduction of $λ^{NMSSM}_{3h_2}/λ^{SM}_{3h_2}$ can occur and minimally reach 10\% when the lightest CP-even Higgs boson mass $m_{h_1}$ is close to the SM-like Higgs boson $m_{h_2}$ due to the large mixing angle between the singlet and doublet Higgs bosons; (3) In the NMSSM with $λ>0.7$, a large enhancement or reduction $-1.1<λ^{NMSSM}_{3h_1}/λ^{SM}_{3h_1}<2$ can occur, which is accompanied by a sizable change of $h_1τ^+τ^-$ coupling. The future colliders, such as the HL-LHC and ILC, will have the capacity to test these large deviations in the NMSSM.

hep-ph↗

arXiv2015

hhh Coupling in SUSY models after LHC run I

We examine the Higgs triple coupling in MSSM and NMSSM under current constraints, which include the LHC measurements, Higgs data, B physics, electroweak precision observables, relic density and so on. The ratio $λ^{\rm MSSM}_{hhh}/λ^{\rm SM}_{hhh}$ is above 0.97, due to the highly constrained parameter space. While the ratio $λ^{\rm NMSSM}_{hhh}/λ^{\rm SM}_{hhh}$ can reach 0.1 under current constraints. The precise measurement in future collider will give a tighter constraint to the Higgs triple coupling in MSSM and NMSSM.

hep-ph↗