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A bstract We calculate in this paper the perturbative gluon transverse momentum dependent parton distribution functions (TMDPDFs) and fragmentation functions (TMDFFs) using the exponential regulator for rapidity divergences. We obtain results for both unpolarized and linearly polarized distributions through next-to-next-to leading order in strong coupling constant, and through O ( ϵ 2 ) in dimensional regulator. We find a nontrivial momentum conservation sum rule for the linearly polarized component for both TMDPDFs and TMDFFs in the N = 1 super-Yang-Mills theory. The TMDFFs are used to calculate the two-loop gluon jet function for the energy-energy correlator in Higgs gluonic decay in the back-to-back limit.

A bstract Energy Correlators measure the energy deposited in multiple detectors as a function of the angles between the detectors. In this paper, we analytically compute the three particle correlator in the collinear limit in QCD for quark and gluon jets, and also in N = 4 super Yang-Mills theory. We find an intriguing duality between the integrals for the energy correlators and infrared finite Feynman parameter integrals, which maps the angles of the correlators to dual momentum variables. In N = 4, we use this duality to express our result as a rational sum of simple Feynman integrals (triangles and boxes). In QCD our result is expressed as a sum of the same transcendental functions, but with more complicated rational functions of cross ratio variables as coefficients. Our results represent the first analytic calculation of a three-prong jet substructure observable of phenomenological relevance for the LHC, revealing unexplored simplicity in the energy flow of QCD jets. They also provide valuable data for improving the understanding of the light-ray operator product expansion.

A bstract We revisit the calculation of perturbative quark transverse momentum de- pendent parton distribution functions and fragmentation functions using the exponential regulator for rapidity divergences. We show that the exponential regulator provides a consistent framework for the calculation of various ingredients in transverse momentum dependent factorization. Compared to existing regulators in the literature, the exponential regulator has a couple of advantages which we explain in detail. As a result, the calcula- tion is greatly simplified and we are able to obtain the next-to-next-to-leading order results up to O ( E 2 ) in dimensional regularization. These terms are necessary for a higher order calculation which is made possible with the simplification brought by the new regulator. As a by-product, we have obtained the two-loop quark jet function for the Energy-Energy Correlator in the back-to-back limit, which is the last missing ingredient for its N 3 LL resummation.

A bstract In this paper we calculate analytically the perturbative matching coefficients for unpolarized quark and gluon Transverse-Momentum-Dependent (TMD) Parton Distribution Functions (PDFs) and Fragmentation Functions (FFs) through Next-to-Next-to-Next-to-Leading Order (N 3 LO) in QCD. The N 3 LO TMD PDFs are calculated by solving a system of differential equation of Feynman and phase space integrals. The TMD FFs are obtained by analytic continuation from space-like quantities to time-like quantities, taking into account the probability interpretation of TMD PDFs and FFs properly. The coefficient functions for TMD FFs exhibit double logarithmic enhancement at small momentum fraction z . We resum such logarithmic terms to the third order in the expansion of α s . Our results constitute important ingredients for precision determination of TMD PDFs and FFs in current and future experiments.

A bstract The soft theorem states that scattering amplitude in gauge theory with a soft gauge-boson emission can be factorized into a hard scattering amplitude and a soft factor. In this paper, we present calculations of the soft factor for processes involving two hard colored partons, up to three loops in QCD. To accomplish this, we developed a systematic method for recursively calculating relevant Feynman integrals using the Feynman-Parameter representation. Our results constitute an important ingredient for the subtraction of infrared singularities at N 4 LO in perturbative QCD. Using the principle of leading transcendentality between QCD and N = 4 super Yang-Mills theory, we determine the soft factor in the latter case to three loops with full-color dependence. As a by-product, we also obtain the finite constant f 2 3 in the Bern-Dixon-Smirnov ansatz analytically, which was previously known numerically only.

A bstract The energy-energy correlation (EEC) function in e + e − annihilation is currently the only QCD event shape observable for which we know the full analytic result at the next-to-leading order (NLO). In this work we calculate the EEC observable for gluon initiated Higgs decay analytically at NLO in the Higgs Effective Field Theory (HEFT) framework and provide the full results expressed in terms of classical polylogarithms, including the asymptotic behavior in the collinear and back-to-back limits. This observable can be, in principle, measured at the future e + e − colliders such as CEPC, ILC, FCC-ee or CLIC. It provides an interesting opportunity to simultaneously probe our understanding of the strong and Higgs sectors and can be used for the determinations of the strong coupling.

Low-angle grain boundary and twin significantly affect precipitation behavior. Twins were introduced into AZ91 magnesium alloys by pre-rolling. And then, aging treatment was carried out in pre-rolled AZ91 magnesium alloys to investigate the precipitation behavior. The results show that the low-angle grain boundary and the extension twin provide the nucleation position for second phase, while double twin with low-elastic strain energy is not favored for the segregation of Al atom, causing that the precipitate hardly nucleates. Second phase firstly precipitates in the low-angle grain boundary and the twin boundary, followed by precipitating inside the twin. The low-angle grain boundary-induced lath-shaped second phase is attributed to dislocation, while the twin-induced precipitate is mainly affected by dislocation and stacking fault. From thermodynamic perspective, the morphology of twin-induced precipitate firstly displays spherical shape and then grows into lath-like shape.

Plants play an important role in maintaining the ecological balance of the biosphere, but often suffer from pathogenic fungi during growth. During our continuing mycological surveys of plant pathogens from terrestrial plants in Jiangxi and Yunnan provinces, China, 24 strains of Pestalotiopsis isolated from diseased and healthy tissues of plant leaves represented eight new species, viz. P. alpinicola , P. camelliicola , P. cyclosora , P. eriobotryae , P. gardeniae , P. hederae , P. machiliana and P. mangifericola . Multi-locus (ITS, tef1-α and tub2 ) phylogenetic analyses were performed using maximum-likelihood and Bayesian inference to reveal their taxonomic placement within Pestalotiopsis . Both molecular phylogenetic analyses and morphological comparisons supported them as eight independent taxa within Pestalotiopsis . Illustrations and descriptions of these eight taxa were provided, in conjunction with comparisons with closely related taxa in the genus. This work highlights the large potential for new fungal species associated with diseased plant leaves.

The Loess Plateau of China has witnessed a remarkable greening trend due to vegetation restoration in recent decades. However, the precipitation response to greening remains unclear, and the hydrological effect of greening is controversial. Here, we revisited biophysical effects of greening on precipitation over the plateau during 2002–2015 using the state‐of‐the‐art water vapor tracer embedded in a regional coupled model. We find that greening can promote the growing season precipitation (0.45 mm·day−1), with 15% and 85% of the precipitation increment resulting from increases in the local evapotranspiration and the water vapor inflow from outside the plateau, respectively. As a consequence, the enhanced precipitation can compensate for the terrestrial water loss driven by the increased evapotranspiration, leading to a slight increase in the water yield. This study highlights the dominant role of the nonlocal effect in precipitation responses to greening in this region. Plain Language Summary In recent decades, the Loess Plateau of China has shown a significant greening trend due to vegetation restoration. In the meantime, greening tends to accelerate the terrestrial water loss via the enhanced evapotranspiration, leading to a decline in the terrestrial water storage. However, such an impact remains controversial because of large uncertainties in precipitation responses to greening. It remains unclear whether the precipitation response can alleviate or aggravate the surface water deficit due to the enhanced evapotranspiration following greening. In this study, we examine impacts of greening on precipitation over the plateau during 2002–2015 using a water vapor tracer embedded in a regional coupled model. The results show that greening can enhance precipitation, which can compensate for evapotranspiration‐driven water loss and consequently increase the water yield in the growing season. 85% of the precipitation increment results from the enhanced water vapor inflow outside the plateau due to responses of large‐scale circulations to greening. The water vapor originating from the enhanced evapotranspiration within the plateau only accounts for 15% of the precipitation increment. This study provides new insight into precipitation responses to greening and the mechanism over the plateau using water vapor tracing. Key Points Biophysical impacts of greening on precipitation over the Loess Plateau are investigated based on WRF‐WVT Greening can promote the growing season precipitation, which can compensate for the evapotranspiration‐driven terrestrial water loss The enhanced precipitation mainly results from enhanced water vapor inflow outside the plateau due to responses of circulations to greening

Saprobic hyphomycetes with high density and species diversity were observed on plant debris. During our mycological surveys in southern China, numerous strains were isolated from dead branches of unidentified plants in the forest of Jiangxi and Fujian provinces, China. Phylogenetic analyses of ITS, LSU, RPB2 , and TEF1 sequence data using maximum-likelihood (ML) and Bayesian inference (BI) methods revealed the systematic placement of several Sporidesmium -like species within Distoseptispora . Based on morphological characteristics and molecular evidence, four new species of Distoseptispora , namely D. fujianensis , D. ganzhouensis , D. nanpingensis and D. subtropica , are introduced, and two known species, D. clematidis and D. yunjushanensis , are reported. This study enhances our knowledge of the species diversity of Distoseptispora in southern China.