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We investigate the leading twist quark generalized transverse momentum distributions (GTMDs) at nonzero skewness in a light-front quark-diquark model for the nucleon motivated by soft-wall AdS/QCD. The boost-invariant longitudinal coordinate, $\sigma=\frac{1}{2} b^- P^+$, is identified as the Fourier conjugate of the skewness. The Fourier transform of the GTMDs with respect to the skewness variable $\xi$ can be employed to provide the Wigner distributions in the boost-invariant longitudinal position space $\sigma$, the coordinate conjugate to light-front time, $\tau=t+z/c$. The Wigner distributions in the longitudinal position space exhibit diffraction patterns, which are analogous to the diffractive scattering of a wave in optics., Comment: 19 pages, 10 figures

The small-scale structure problems of the universe can be solved by self-interacting dark matter that becomes strongly interacting at low energies. A particularly predictive model is resonant short-range self-interactions, with a dark-matter mass of about 19 GeV and a large S-wave scattering length of about 17 fm. Such a model makes definite predictions for the few-body physics of weakly bound clusters of the dark-matter particles. We calculate the production of two-body bound clusters by three-body recombination in the early universe under the assumption that the dark matter particles are identical bosons, which is the most favorable case for forming larger clusters. The fraction of dark matter in the form of two-body bound clusters can increase by as much as 4 orders of magnitude when the dark-matter temperature falls below the binding energy, but its present value remains less than \(10^{-6}\).

We consider di-jet production in hadron collisions where a transverse veto is imposed on radiation for (pseudo-)rapidities in the central region only, where this central region is defined with rapidity cutoff. For the case where the transverse measurement (e.g., transverse energy or min p T for jet veto) is parametrically larger relative to the typical transverse momentum beyond the cutoff, the cross section is insensitive to the cutoff parameter and is factorized in terms of collinear and soft degrees of freedom. The virtuality for these degrees of freedom is set by the transverse measurement, as in typical transverse-momentum dependent observables such as Drell-Yan, Higgs production, and the event shape broadening. This paper focuses on the other region, where the typical transverse momentum below and beyond the cutoff is of similar size. In this region the rapidity cutoff further resolves soft radiation into (u)soft and soft-collinear radiation with different rapidities but identical virtuality. This gives rise to rapidity logarithms of the rapidity cutoff parameter which we resum using renormalization group methods. We factorize the cross section in this region in terms of soft and collinear functions in the framework of soft-collinear effective theory, then further refactorize the soft function as a convolution of the (u)soft and soft-collinear functions. All these functions are calculated at one-loop order. As an example, we calculate a differential cross section for a specific partonic channel, qq ′ → qq ′ , for the jet shape angularities and show that the refactorization allows us to resum the rapidity logarithms and significantly reduce theoretical uncertainties in the jet shape spectrum.

We discuss a new approach for jet physics analysis by using subtraction between cumulants of jet substructure observables. The subtracted cumulants are insensitive to soft-particle background uncorrelated with the hard process and allow comparisons between theoretical results and experimental measurements without the complication of soft background like underlying and pile-up events. We find our method using jet mass cumulants efficiently eliminates the background in Monte Carlo simulations and ATLAS jet mass measurements and they show a good agreement with our analytic calculations performed using soft-collinear effective theory.

In this paper we study the transverse energy spectrum for the Drell-Yan process. The transverse energy is measured within the central region defined by a (pseudo-) rapidity cutoff. Soft-collinear effective theory (SCET) is used to factorize the cross section and resum large logarithms of the rapidity cutoff and ratios of widely separated scales that appear in the fixed order result. We develop a framework which can smoothly interpolate between various regions of the spectrum and eventually match onto the fixed order result. This way a reliable calculation is obtained for the contribution of the initial state radiation to the measurement. By comparing our result for Drell-Yan against Pythia we obtain a simple model that describes the contribution from multiparton interactions (MPI). A model with little or no dependence on the primary process gives results in agreement with the simulation. Based on this observation we propose MPI insensitive measurements. These observables are insensitive to the MPI contributions as implemented in Pythia and we compare against the purely perturbative result obtained with the standard collinear factorization., 30 pages, 5 figures

The small-scale structure problems of the universe can be solved by self-interacting dark matter that becomes strongly interacting at low energy. A particularly predictive model for the self-interactions is resonant short-range interactions with an S-wave scattering length that is much larger than the range. The velocity dependence of the cross section in such a model provides an excellent fit to self-interaction cross sections inferred from dark-matter halos of galaxies and clusters of galaxies if the dark-matter mass is about 19 GeV and the scattering length is about 17 fm. Such a model makes definite predictions for the few-body physics of weakly bound clusters of the dark-matter particles. The formation of the two-body bound cluster is a bottleneck for the formation of larger bound clusters. We calculate the production of two-body bound clusters by three-body recombination in the early universe under the assumption that the dark matter particles are identical bosons, which is the most favorable case. If the dark-matter mass is 19 GeV and the scattering length is 17 fm, the fraction of dark matter in the form of two-body bound clusters can increase by as much as 4 orders of magnitude when the dark-matter temperature falls below the binding energy, but its present value remains less than 10^(-6). The present fraction can be increased to as large as 10^(-3) by relaxing the constraints from small-scale structure and decreasing the mass of the dark matter particle., 35 pages, 8 figure, v2: published version, a comment on spin-1/2 dark matter case added

We introduce a new approach for jet physics studies using subtracted cumulants of jet substructure observables, which are shown to be insensitive to contributions from soft-particle emissions uncorrelated with the hard process. Therefore, subtracted cumulants allow comparisons between theoretical calculations and experimental measurements without the complication of large background contaminations such as underlying and pileup events in hadron collisions. We test our method using subtracted jet mass cumulants by comparing Monte Carlo simulations to analytic calculations performed using soft-collinear effective theory. We find that, for proton-proton collisions, the method efficiently eliminates contributions from multiparton interactions and pileup events. We also find within theoretical uncertainty that our analytic calculations are in good agreement with the subtracted cumulants calculated by using ATLAS jet mass measurements.

We present a simple observation about soft amplitudes and soft functions appearing in factorizable cross sections in ee , ep , and pp collisions that has not clearly been made in previous literature, namely, that the hemisphere soft functions that appear in event shape distributions in e + e − → dijets , deep inelastic scattering (DIS), and in Drell–Yan (DY) processes are equal in perturbation theory up to O ( α s 2 ) , even though individual amplitudes may have opposite sign imaginary parts due to changing complex pole prescriptions in eikonal propagators for incoming vs. outgoing lines. We also explore potential generalizations of this observation to soft functions for other observables or with more jets in the final state.

We study the recombination process of three atoms scattering into an atom and diatomic molecule in heteronuclear mixtures of ultracold atomic gases with large and positive interspecies scattering length at finite temperature. We calculate the temperature dependence of the three-body recombination rates by extracting universal scaling functions that parametrize the energy dependence of the scattering matrix. We compare our results to experimental data for the 40K-87Rb mixture and make a prediction for 6Li-87Rb. We find that contributions from higher partial wave channels significantly impact the total rate and, in systems with particularly large mass imbalance, can even obliterate the recombination minima associated with the Efimov effect., 19 pages, 5 figures

We consider a homogeneous, balanced gas of strongly interacting fermions in two spin states interacting through a large scattering length. Finite range corrections are needed for a quantitative description of data which experiments and numerical simulations have provided. We use a perturbative field theoretical framework and a tool called the Operator Product Expansion (OPE), which together allow for the expression of finite range corrections to the universal relations and momentum distribution. Using the OPE, we derive the $1/k^6$ part of the momentum tail, which is related to the sum of the derivative of the energy with respect to the finite range and the averaged kinetic energy of opposite spin pairs. By comparing the $1/k^4$ term and the $1/k^6$ correction in the momentum distribution to provided Quantum Monte Carlo (QMC) data, we show that including the $1/k^6$ part offers marked improvements. Our field theoretical approach allows for a clear understanding of the role of the scattering length and finite effective range in the universal relations and the momentum distribution., Comment: 13 pages, 7 figure, 4 tables, Eqs.(13), (15), and (59) are corrected with an additional term called C', published version

© Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND 4.0). A high precision calculation of the event shape DIS thrust, with next-to-next-to-next-to-leadinglogarithmic resummation and a rigorous treatment of hadronization corrections, is presented. Perturbative resummation uncertainties in the cross section are reduced to the 2% level for a significant region of the HERA phase space in x and Q, thus allowing for new accurate measurements of αs(mZ)., Department of Energy Office of Nuclear Physics (Contract DE-FG02-94ER40818)

A new numerical treatment in the Crank-Nicholson method with the imaginary time evolution operator is presented in order to solve the Schr\"{o}dinger equation. The original time evolution technique is extended to a new operator that provides a systematic way to calculate not only eigenvalues of ground state but also of excited states. This new method systematically produces eigenvalues with accuracies of eleven digits with the Cornell potential that covers non-perturbative regime. An absolute error estimation technique based on a power counting rule is implemented. This method is examined with exactly solvable problems and produces the numerical accuracy down to 10$^{-11}$., Comment: 10 pages, 1 figure. Submitted to Phys. Rev. Lett

Measurements by the Belle Collaboration of the exclusive J/psi + eta_c and inclusive J/psi +cc-bar+X productions in e^+ e^- annihilation differ substantially from theoretical predictions based on the nonrelativistic QCD factorization approach. In order to test if such a discrepancy is originated from the large perturbative corrections to the hard-scattering amplitude, we study inclusive production of four charm hadrons in e^+e^- annihilation at B factories., 4 pages, 2 eps figures, uses ws-ijmpa.cls, talk presented at the International Conference on QCD and Hadronic Physics, Beijing, China, June, 16--20, 2005

In a recent experiment with ultracold trapped Rb-85 atoms, Makotyn et al. have studied a quantum-degenerate Bose gas in the unitary limit where its scattering length is infinitely large. We show that the observed momentum distributions are compatible with a universal relation that expresses the high-momentum tail in terms of the 2-body and the 3-body contacts. We determine the 2- and 3-body contact densities for the unitary Bose gas with number density n to be approximately 20n^{4/3} and 2n^{5/3}, respectively. We also show that the observed atom loss rate is compatible with that from 3-atom inelastic collisions, which gives a contribution proportional to the 3-body contact, but the loss rate is not compatible with that from 2-atom inelastic collisions, which gives a contribution proportional to the 2-body contact. We point out that the contacts could be measured independently by using the virial theorem near and at unitarity., Comment: 5 pages, 1 figure

We predict cross sections in deep inelastic scattering (DIS) for the production of two jets---one along the proton beam direction created by initial state radiation (ISR) and another created by final state radiation after the hard collision. Our results include fixed order corrections and a summation of large logarithms up to next-to-next-to-leading logarithmic (NNLL) accuracy in resummed perturbation theory. We make predictions for three versions of a DIS event shape 1-jettiness, each of which constrains hadronic final states to be well collimated into two jets along the beam and final-state jet directions, but which differ in their sensitivity to the transverse momentum of the ISR from the proton beam. We use the tools of soft collinear effective theory (SCET) to derive factorization theorems for these three versions of 1-jettiness. The sensitivity to the ISR gives rise to significantly different structures in the corresponding factorization theorems---for example, dependence on either the ordinary or the generalized kperp-dependent beam function. Despite the differences among 1-jettiness definitions, we show that the leading nonperturbative correction that shifts the tail region of their distributions is given by a single universal nonperturbative parameter Omega1, even accounting for hadron mass effects. Finally, we give numerical results for Q^2 and x values explored at the HERA collider, emphasizing that the target of our factorization-based analyses is to open the door for higher-precision jet phenomenology in DIS., Comment: 53 pages, 13 figures, 3 tables. Version published in Physical Review D

Systems consisting of identical bosons with a large scattering length satisfy universal relations determined by 2-body physics that are similar to those for fermions with two spin states. They require the momentum distribution to have a large-momentum 1/k(4) tail and the radio-frequency transition rate to have a high-frequency 1/ω(3/2) tail, both of which are proportional to the 2-body contact. Identical bosons also satisfy additional universal relations that are determined by 3-body physics and involve the 3-body contact, which measures the probability of 3 particles being very close together. The coefficients of the 3-body contact in the 1/k(5) tail of the momentum distribution and in the 1/ω(2) tail of the radio-frequency transition rate are log-periodic functions of k and ω that depend on the Efimov parameter.

$^{6}\mathrm{Li}$ atoms in the three lowest hyperfine states display universal properties when the $S$-wave scattering length between each pair of states is large. Recent experiments reported four pronounced features arising from Efimov physics in the atom-dimer relaxation rate, namely two resonances and two local minima. We use the universal effective-field theory to calculate the atom-dimer relaxation rate at zero temperature. Our results describe the four features qualitatively and imply there is a hidden local minimum. In the vicinity of the resonance at 685 G, we perform a finite temperature calculation which improves the agreement of theory and experiment. We conclude that finite temperature effects cannot be neglected in the analysis of the experimental data.

We construct line shapes for the X(3872) that generalize the Flatte and zero-range line shapes that have been considered previously. These line shapes are associated with scattering amplitudes that are exactly unitary for real values of the interaction parameters and can be derived from a renormalizable quantum field theory. The new line shapes can be used to discriminate between the alternative binding mechanisms in which the X(3872) is generated either dynamically by charm meson interactions or by a resonance near the D^{*0} Dbar^0 threshold. If the resonance is identified with the P-wave charmonium state chi'_{c1}, the interaction parameters can be constrained by using charmonium phenomenology. We analyze data on the X(3872) and also data from the Belle and Babar Collaborations on the invariant mass distribution of the charm mesons from the decay B -> K + D^{*0} Dbar^0 up to 4000 MeV. Our analysis is compatible with the mechanism for the X(3872) being either a fine-tuning of charm meson interactions or the fine-tuning of the chi'_{c1} to the D^{*0} Dbar^0 threshold. In particular, the data do not exclude a separate chi'_{c1} resonance between the D^{*+} D^- threshold and 4000 MeV., 50 pages, 5 figures, 2 tables. Version published in Physical Review D

Universal relations that hold for any state provide powerful constraints on systems consisting of fermions with two spin states interacting with a large scattering length. In radio-frequency (rf) spectroscopy, the mean shift in the rf frequency and the large frequency tail of the rf transition rate are proportional to the contact, which measures the density of pairs with small separations. We show that these universal relations can be derived and extended by using the short-time operator product expansion of quantum field theory. This is a general method for identifying aspects of many-body physics that are controlled by few-body physics., 4 pages

A new narrow three-atom loss resonance associated with an Efimov trimer crossing the three-atom threshold has recently been discovered in a many-body system of ultracold {sup 6}Li atoms in the three lowest hyperfine spin states at a magnetic field near 895 G. O'Hara and coworkers have used measurements of the three-body recombination rate in this region to determine the complex three-body parameter associated with Efimov physics. Using this parameter as the input, we calculate the universal predictions for the spectrum of Efimov states and for the three-body recombination rate in the universal region above 600 G where all three scattering lengths are large. We predict an atom-dimer loss resonance at 672+-2 G associated with an Efimov trimer disappearing through an atom-dimer threshold. We also predict an interference minimum in the three-body recombination rate at 759+-1 G where the three-spin mixture may be sufficiently stable to allow experimental study of the many-body system.

The three-body recombination rate at threshold for distinguishable atoms with large negative pair scattering lengths is calculated in the zero-range approximation. The only parameters in this limit are the 3 scattering lengths and the Efimov parameter, which can be complex-valued. We provide semianalytic expressions for the cases of 2 or 3 equal scattering lengths, and we obtain numerical results for the general case of 3 different scattering lengths. Our general result is applied to the three lowest hyperfine states of 6Li atoms. Comparisons with recent experiments provide indications of loss features associated with Efimov trimers near the 3-atom threshold.

The gluon collision process that creates a heavy-quark-antiquark pair with small relative momentum and large transverse momentum predicts at leading-order in the QCD coupling constant that the transverse polarization of the pair should increase with its transverse momentum. Measurements at the Fermilab Tevatron of the polarization of charmonium and bottomonium states with respect to a particular spin-quantization axis are inconsistent with this prediction. However the predicted rate of approach to complete transverse polarization depends on the choice of spin-quantization axis. We introduce axes that maximize and minimize the transverse polarization from the leading-order gluon collision process. They are determined by the direction of the jet that provides most of the balancing transverse momentum., Comment: 10 pages, 1 figure, minor corrections, version published in Phys. Rev. D

The three-body recombination rate at threshold for distinguishable atoms with large negative pair scattering lengths is calculated in the zero-range approximation. The only parameters in this limit are the 3 scattering lengths and the Efimov parameter, which can be complex-valued. We provide semianalytic expressions for the cases of 2 or 3 equal scattering lengths, and we obtain numerical results for the general case of 3 different scattering lengths. Our general result is applied to the three lowest hyperfine states of 6Li atoms. Comparisons with recent experiments provide indications of loss features associated with Efimov trimers near the 3-atom threshold.

A set of universal relations between various properties of any few-body or many-body system consisting of fermions with two spin states and a large but finite scattering length have been derived by Shina Tan. We derive generalizations of the Tan relations for a two-channel model for fermions near a Feshbach resonance that includes a molecular state whose detuning energy controls the scattering length. We use quantum field theory methods, including renormalization and the operator product expansion, to derive these relations. They reduce to the Tan relations as the scattering length is made increasingly large., 25 pages, 8 figures

The leading-order parton processes that produce a dilepton with large transverse momentum predict that the transverse polarization should increase with the transverse momentum for almost any choice of the quantization axis for the spin of the virtual photon. The rate of approach to complete transverse polarization depends on the choice of spin quantization axis. We propose axes that optimize that rate of approach. They are determined by the momentum of the dilepton and the direction of the jet that provides most of the balancing transverse momentum., 4 pages, 1 figure, minor corrections, version published in Phys. Rev. D

For identical bosons with a large scattering length, the dependence of the 3-body recombination rate on the collision energy is determined in the zero-range limit by universal functions of a single scaling variable. There are six scaling functions for angular momentum zero and one scaling function for each higher partial wave. We calculate these universal functions by solving the Skorniakov--Ter-Martirosian equation. The results for the 3-body recombination as a function of the collision energy are in good agreement with previous results from solving the 3-body Schroedinger equation for 4He atoms. The universal scaling functions can be used to calculate the 3-body recombination rate at nonzero temperature. We obtain an excellent fit to the data from the Innsbruck group for 133Cs atoms with a large positive scattering length., Comment: 34 pages, 10 figures, published version

We compute derived quantities for various values of the model parameter of the Cornell potential model for the S-wave heavy quarkonia with radial quantum numbers n=1, 2, and 3. Our results can be used to determine leading and relative-order-v^2 nonrelativistic quantum chromodynamics matrix elements for S-wave charmonia and bottomonia such as psi(2S), eta_c(2S), and Upsilon(nS) for n=1, 2, and 3. These matrix elements will be essential ingredients for resumming relativistic corrections to processes involving those S-wave heavy quarkonium states., Comment: 10 pages, 2 figures, 1 table, version to be published in J. Korean Phys. Soc

Based on the nonrelativistic QCD (NRQCD) factorization formalism, we calculate the inclusive charm production rate in {upsilon}(nS) decay at leading order in the strong coupling constant {alpha}{sub s} and the relative velocity v of the b quark in the quarkonium rest frame. The branching fractions for {upsilon}(nS) to charm for n=1, 2, and 3 are all around 7%-9%. About 60% of the branching fraction into charm is from annihilation of the color-singlet bb pair into {gamma}*{yields}cc. Most of the remaining branching fraction is from annihilation of the color-singlet bb pair decaying into ccgg. We also compute the momentum distributions of the charm quark and charmed hadrons in the decays. The virtual-photon contribution to the charm-quark momentum distribution is concentrated at the end point while the ccgg contribution is broad. The momentum distributions for charmed hadrons are obtained by convolving the charm-quark momentum distribution with charm fragmentation functions. This makes the momentum distributions for charmed hadrons softer than that for the charm quark. This effect is particularly significant in the virtual-photon contribution.

We present a new computation of S-wave color-singlet nonrelativistic QCD matrix elements for the J/psi and the eta_c. We compute the matrix elements of leading order in the heavy-quark velocity v and the matrix elements of relative order v^2. Our computation is based on the electromagnetic decay rates of the J/psi and the eta_c and on a potential model that employs the Cornell potential. We include relativistic corrections to the electromagnetic decay rates, resumming a class of corrections to all orders in v, and find that they significantly increase the values of the matrix elements of leading order in v. This increase could have important implications for theoretical predictions for a number of quarkonium decay and production processes. The values that we find for the matrix elements of relative order v^2 are somewhat smaller than the values that one obtains from estimates that are based on the velocity-scaling rules of nonrelativistic QCD., 31 pages, minor corrections, version published in Phys. Rev. D

For atoms with large scattering length, the dependence of the three-body recombination rate on the collision energy is determined by the scattering length and the Efimov three-body parameters and can be expressed in terms of universal functions of a single scaling variable. We use published results on the three-body recombination rate for {sup 4}He atoms to constrain the universal functions. We then use those universal functions to calculate the three-body recombination rate for other atoms with large scattering length at nonzero temperature. The constraints from the {sup 4}He results are strong if the scattering length is near the minimum of the three-body recombination rate at threshold. We apply our results to {sup 133}Cs atoms with a large positive scattering length, and compare them with experimental results from the Innsbruck group.

We calculate the inclusive decay rate of the spin-triplet bottomonium states chi_{bJ} into charm hadrons, including the leading-order color-singlet and color-octet bb-bar annihilation mechanisms. We also calculate the momentum distribution of the charm quark from the decay of chi_{bJ}. The infrared divergences from the color-singlet process bb-bar -> cc-bar g are factored into the probability density at the origin for a bb-bar pair in a color-octet state. That probability density can be determined phenomenologically from the fraction of decays of chi_{bJ} that include charm hadrons. It can then be used to predict the partial widths into light hadrons for all four states in the P-wave bottomonium multiplet., 39 pages, 3 figures, Minor corrections, Version published in Phys. Rev. D

We compute relativistic corrections to the process e+e− → J/ψ + ηc and find that they resolve the discrepancy between theory and experiment.

It has been suggested in Ref. [A. E. Bondar and V. L. Chernyak, Phys. Lett. B 612, 215 (2005)] that the disagreement between theoretical calculations and experimental observations for the rate for the process e{sup +}e{sup -}{yields}J/{psi}+{eta}{sub c} at the B factories might be resolved by using the light-cone method to take into account the relative momentum of the heavy-quark and antiquark in the quarkonia. The light-cone result for the production cross section in Ref. [A. E. Bondar and V. L. Chernyak, Phys. Lett. B 612, 215 (2005)] is almost an order-of-magnitude larger than existing NRQCD factorization results. We investigate this apparent theoretical discrepancy. We compute light-cone distribution functions by making use of quarkonium wave functions from the Cornell potential model. Our light-cone distribution functions are similar in shape to those of Ref. [A. E. Bondar and V. L. Chernyak, Phys. Lett. B 612, 215 (2005)] and yield a similar cross section. However, when we subtract parts of the light-cone distribution functions that correspond to corrections of relative-order {alpha}{sub s} in the NRQCD approach, we find that the cross section decreases by about a factor of three. When we set certain renormalization factors Z{sub i} in the light-cone calculation equalmore » to unity, we find a further reduction in the cross section of about a factor of two. The resulting light-cone cross section is similar in magnitude to the NRQCD factorization cross sections and shows only a modest enhancement over the light-cone cross section in which the relative momentum of the heavy-quark and antiquark is neglected.« less

Measurements by Belle Collaboration of the cross section for inclusive J/{psi} production in e{sup +}e{sup -} annihilation have been a serious challenge to current heavy-quarkonium theory. In particular, the measured cross sections for exclusive J/{psi}+{eta}{sub c} and inclusive J/{psi}+cc+X differ from nonrelativistic QCD predictions by an order of magnitude. In order to check if other available alternative theories can resolve such a large discrepancy, we calculate the cross section for inclusive J/{psi}+cc+X based on the color-evaporation model. As a phenomenological model, the color-evaporation model is still employed to predict cross sections for inclusive quarkonium production in various processes. Our results show that the color-evaporation-model prediction is even smaller than the nonrelativistic QCD prediction by an order of magnitude. The resultant color-evaporation-model prediction for the J/{psi}+cc+X fraction in the inclusive J/{psi} production cross section is 0.049, while the empirical value measured by Belle Collaboration is 0.82.

Measurements by the Belle Collaboration of the exclusive production of two charmonia in e{sup +}e{sup -} annihilation differ substantially from theoretical predictions. Till now, no conclusive explanation for this remarkable discrepancy has been provided. Even the origin of the discrepancy is not identified, yet. We suggest that the measurement of four-charm events in Belle data must provide a strong constraint in identifying the origin of this large discrepancy. Our prediction of the cross section for e{sup +}e{sup -}{yields}cccc, in lowest order in strong coupling constant, at {radical}(s)=10.6 GeV is about 0.1 pb. If measured four-charm cross section is compatible with the prediction based on perturbative QCD, it is very likely that factorization of the hadronization process from perturbative part may be significantly violated or there exists a new production mechanism. If the cross section for the four-charm event is also larger than the prediction like that for the exclusive J/{psi}+{eta}{sub c} production, perturbative QCD expansion itself will be proved to be unreliable and loses predictive power.

We present angularity differential cross-section for the deep inelastic scattering process (DIS) in the framework of soft-collinear effective theory (SCET). Using SCET, the cross-section is factorized in terms of hard, jet, beam and soft functions. Our result includes resummation of the large logarithms up to next-to-next leading logarithmic (NNLL) accuracy. The numerical results presented here for DIS angularity cross-section can be explored by the future EIC., Comment: 5 pages, 1 fugures, to appear in the proceedings of the LC2019-QCD on the Light-Cone from hadron to heavy Ions, 16-20 September 2019, Ecole Polytechnique, France

We present an analytic $$ \mathcal{O}\left({\alpha}_s\right) $$ calculation of cross sections in deep inelastic scattering (DIS) dependent on an event shape, 1-jettiness, that probes final states with one jet plus initial state radiation. This is the first entirely analytic calculation for a DIS event shape cross section at this order. We present results for the differential and cumulative 1-jettiness cross sections, and express both in terms of structure functions dependent not only on the usual DIS variables x, Q 2 but also on the 1-jettiness τ. Combined with previous results for log resummation, predictions are obtained over the entire range of the 1-jettiness distribution.