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2D energy-momentum tensor distributions of nucleon in a large- N c quark model from ultrarelativistic to nonrelativistic limit
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Disentangling quarks and gluons in CMS open data
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Quark-model relations among TMDs in the parton model
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RI / MOM and RI / SMOM renormalization of quark bilinear operators using overlap fermions
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Independence of current components, polarization vectors, and reference frames in the light-front quark model analysis of meson decay constants
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Heavy quark diffusion coefficient with gradient flow
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Pseudoscalar meson decay constants and distribution amplitudes up to the twist-4 in the light-front quark model
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Role of strange quarks in the D -term and cosmological constant term of the proton
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Measurements of $t\overline tH$ Production and the CP Structure of the Yukawa Interaction between the Higgs Boson and Top Quark in the Diphoton Decay Channel
The first observation of the t t ¯ H process in a single Higgs boson decay channel with the full reconstruction of the final state ( H → γ γ ) is presented, with a significance of 6.6 standard deviations ( σ ). The C P structure of Higgs boson couplings to fermions is measured, resulting in an exclusion of the pure C P -odd structure of the top Yukawa coupling at 3.2 σ . The measurements are based on a sample of proton-proton collisions at a center-of-mass energy s = 13 TeV collected by the CMS detector at the LHC, corresponding to an integrated luminosity of 137 fb – 1 . The cross section times branching fraction of the t t ¯ H process is measured to be σ t t ¯ H B γ γ = 1.56 – 0.32 + 0.34 fb , which is compatible with the standard model prediction of 1.13 – 0.11 + 0.08 fb . The fractional contribution of the C P -odd component is measured to be f C P H t t = 0.00 ± 0.33 .
C P Properties of Higgs Boson Interactions with Top Quarks in the t t ¯ H and t H Processes Using H → γ γ with the ATLAS Detector
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Evidence for Top Quark Production in Nucleus-Nucleus Collisions
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Search for Flavor-Changing Neutral Current Interactions of the Top Quark and Higgs Boson in Final States with Two Photons in Proton-Proton Collisions at s = 13 TeV
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Search for Higgs Boson Pair Production in the Four b Quark Final State in Proton-Proton Collisions at s = 13 TeV
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3D Structure of Jet-Induced Diffusion Wake in an Expanding Quark-Gluon Plasma
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Quark and gluon two-loop beam functions for leading-jet p T and slicing at NNLO
We compute the complete set of two-loop beam functions for the transverse momentum distribution of the leading jet produced in association with an arbitrary colour-singlet system. Our results constitute the last missing ingredient for the calculation of the jet-vetoed cross section at small veto scales at the next-to-next-to-leading order, as well as an important ingredient for its resummation to next-to-next-to-next-to-leading logarithmic order. Our calculation is performed in the soft-collinear effective theory framework with a suitable regularisation of the rapidity divergences occurring in the phase-space integrals. We discuss the occurrence of soft-collinear mixing terms that might violate the factorisation theorem, and demonstrate that they are naturally absorbed into the beam functions at two loops in the exponential rapidity regularisation scheme when performing a multipole expansion of the measurement function. As in our recent computation of the two-loop soft function, we present the results as a Laurent expansion in the jet radius R. We provide analytic expressions for all flavour channels in x space with the exception of a set of R-independent non-logarithmic terms that are given as numerical grids. We also perform a fully numerical calculation with exact R dependence, and find that it agrees with our analytic expansion at the permyriad level or better. Our calculation allows us to define a next-to-next-to-leading order slicing method using the leading-jet p T as a slicing variable. As a check of our results, we carry out a calculation of the Higgs and Z boson total production cross sections at the next-to-next-to-leading order in QCD.
Search for a resonance decaying into a scalar particle and a Higgs boson in the final state with two bottom quarks and two photons in proton–proton collisions at $\sqrt{s}$ = 13 TeV with the ATLAS detector
A search for the resonant production of a heavy scalar X decaying into a Higgs boson and a new lighter scalar S, through the process X → S(→ $b\overline{b}$)H(→γγ), where the two photons are consistent with the Higgs boson decay, is performed. The search is conducted using an integrated luminosity of 140 fb -1 of proton-proton collision data at a centre-of-mass energy of 13 TeV recorded with the ATLAS detector at the Large Hadron Collider. The search is performed over the mass range 170 ≤ m X ≤ 1000 GeV and 15 ≤ m S ≤ 500 GeV. Parameterised neural networks are used to enhance the signal purity and to achieve continuous sensitivity in a domain of the (m X , m S ) plane. No significant excess above the expected background is found and 95% CL upper limits are set on the cross section times branching ratio, ranging from 39 fb to 0.09 fb. The largest deviation from the background-only expectation occurs for (m X , m S ) = (575, 200) GeV with a local (global) significance of 3.5 (2.0) standard deviations.