Status of QCD

Status of Global Analysis of Neutrino Oscillation Data

In this talk we discuss some details of the analysis of neutrino data and our present understanding of neutrino masses and mixing. This talk is based on hep-ph/0306001, hep-ph/0306226 and hep-ph/0404085.

Status of neutrino mixing

Talk presented at the 7th International Workshop on Neutrino Telescopes, Venezia, February 1996.

QCD and Hadronic Interactions: Summary talk for Moriond 97

This talk covers a selection of topics that were discussed at this meeting in the non-heavy-ion sessions: (a) The high $Q^{2}$ events at HERA and their theoretical interpretation. (b) The issues of how well we know the predictions of QCD, with a particular emphasis on resummation. (c) Anomalies in jet production in association with $W$ bosons at the Tevatron and in dijet production in deep-inelastic scattering. (d) Diffractive hard scattering.

Talk on QCD Calculations by Numerical Integration

Calculations in Quantum Chromodynamics are typically performed using a method pioneered by Ellis, Ross and Terrano in 1981. In this method, one combines numerical integrations over the momenta of final state particles with analytical integrations over the momenta of virtual particles. I discuss a more flexible method in which one performs all of the integrations numerically.

Concluding talk at NOW 2006

This writeup summarizes the status of neutrino oscillations, including recent fluxes and experimental data, as of summer 2006. A discussion is given on the current status of absolute scale of neutrino mass from tritium, neutrinoless double beta decay and cosmological observations, as well as the prospects for the next generation of experiments, including lepton flavor violation searches, and their theoretical significance.

QCD Theory at the XL Rencontre de Moriond: Fish Eyes and Physics

I review a selection of the talks at the QCD Session of the XL Rencontre de Moriond, talks either by theorists or else of special theoretical interest. I use the talks to provide some assessment of where we stand with respect to the problems and opportunities facing QCD theory.

Can one still talk of a Broken Quantum Chromodynamics?

The exact QCD is one of the cornerstones of particle physics. Hence it would appear that there should exist no physical situation where a broken version of QCD may have any relevance. However, here I shall show that a spontaneously broken version of QCD may have been significant in an early universe scenario. How this can be made compatible with the exact QCD shall be pointed out. This gives rise to a new cosmological dark matter object (called "rungion").

STATUS OF PERTURBATIVE QCD EVALUATION OF HADRONIC DECAY RATES OF THE Z AND HIGGS BOSONS

We review the current status of the high order perturbative QCD evaluation of the hadronic decay rates of the Z and Higgs bosons. A systematic classification of the various types of QCD corrections to $O(α_s^2)$ and $O(α_s^3)$ is made and their numerical status is clarified.

Present Status of the Muon Anomalous Magnetic Moment

These pages, based on my talk at the Montpellier 14th International Conference in QCD, provide us with a short update of the Standard Model contributions to the Muon Anomalous Magnetic Moment.

The Electroweak Phase Transition: A Status Report

A talk presented at "String Gravity and Physics at the Planck Energy Scale", Erice, September 1995, summarizing the current understanding of the electroweak phase transition.

Summary of the Workshop ``the QCD Phase Transitions'' Brookhaven National Laboratory, November 4-7 1998

This is the full text of the summary talk: copies of transparancies of all talks with Introduction and Summary would be mailed to participants from RIKEN/BNL center

The status of NLL BFKL

This talk summarises the current status of the NLL corrections to BFKL physics and discusses the question of small-x factorisation.

QCD calculations for the LHC: status and prospects

We briefly review the status of high precision QCD predictions available for LHC processes, focusing on corrections beyond NLO and ways to make the latter available in a convenient format. As a phenomenological example we discuss the two-loop corrections to Higgs boson pair production in gluon fusion.

QCD spin physics: status, and prospects for RHIC

We review some of the recent developments in QCD spin physics and highlight the spin program now underway at RHIC.

QCD '98: status of the power corrections

We review status of the power corrections in QCD. The topics include shape variables, unconventional 1/Q^2 corrections, tachyonic gluon mass as a fit parameter to the 1/Q^2 corrections. The selection of the material is determined mostly by results presented at the Conference QCD'98 (Montpellier, July 1998). Some background comments are also included.

Status of resummed predictions for QCD final state observables

We provide a brief review of the current status of resummed predictions for QCD final state observables such as event shapes and jet rates in a variety of different hard processes. Particular emphasis is given to more recent developments such as the study of non global observables, development of generalized resummation formulae and resummations for new types of event shape variables.

Status of QCD

I have been asked to discuss the status of QCD. It seems to me that there are three main points to be made about the present status of QCD: $\bullet$ QCD is right, and we can do many beautiful things with it. $\bullet$ There are several important concrete problems that lie just beyond the edge of our current understanding. $\bullet$ There are some foundational issues in QCD, and some recent developments, that may point toward entirely new directions. These points will, I believe, emerge quite clearly from the following more detailed discussion. The discussion will be in three parts. I'll first…

Concluding Talk: A Theorist Overview on Particle Physics

This is a Concluding Talk, not a Summary of the FPCP 2011 Conference. I will first make some comments on the status and the prospects of particle physics and then review some of the highlights that particularly impressed me at this Conference (a subjective choice).

The QCD Phase Transition: From the Microscopic Mechanism to Signals Talk at Renconres de Moriond - 97

This talk consists of two very different parts: the first one deals with non-perturbative QCD and physics of the chiral restoration, the second with rather low-key (and still unfinished) work aiming at obtaining EOS and other properties of hot/dense hadronic matter from data on heavy ion collisions. The microscopic mechanism for chiral restoration phase transition is a transition from randomly placed tunneling events (instantons) at low T to a set of strongly correlated tunneling-anti-tunneling events (known as instanton - anti-instanton molecules) at high T. Many features of the transition ca…

Status Report of NNLO QCD Calculations

We review recent progress in next-to-next-to-leading order (NNLO) perturbative QCD calculations with special emphasis on results ready for phenomenological applications. Important examples are new results on structure functions and jet or Higgs boson production. In addition, we describe new calculational techniques based on twistors and their potential for efficient calculations of multiparticle amplitudes.

In combat with nonperturbative QCD

This talk is the second part of the summary of the theory section at DIS'97. We demonstrated that theory of the "hard" processes, based on QCD, has achieved a better understanding of available experimental data during the past year. This was due to the remarkable success achieved in calculating of high order corrections in perturbative QCD (see the summary talk of S. Forte) as well as progress in nonpertutbative QCD approaches.

The Status of The Standard Model

Talk given at the XVIII International Symposium on Lepton-Photon Interactions, Hamburg, 1997. 1. Introduction 2. Status of the Data 3. Precision Electroweak Data and the Standard Model 4. A More General Analysis of Electroweak Data 5. The Case for Physics beyond the Standard Model 6. The Search for the Higgs 7. New Physics at HERA? 8. Conclusion

Gluon structure function for deeply inelastic scattering with nucleus in QCD

In this talk we present the first calculation of the gluon structure function for nucleus in QCD. We discuss the Glauber formula for the gluon structure function and the violation of this simple approach that we anticipate in QCD. (Talk given by E. Levin at QCD and nuclear target session at the Workshop on Deep Inelastic Scattering and QCD, Paris, April 1995).

QCD and Multiparticle Production - The Status of the Perturbative Cascade

I discuss recent developments in the QCD cascade formalism. I focus on the importance of and uncertainties in higher order corrections to the Modified Leading Log approximation for final-state radiation. I also talk about the CCFM and LDC evolution equations for initial-state radiation in DIS.

Status of diboson production in NNLO QCD

We present results from the first fully differential next-to-next-to leading order NNLO QCD computation of ZZ production, including off-shell effects, the leptonic decay and non-resonant contributions. We compare theoretical predictions to fiducial cross sections and distributions measured by ATLAS and CMS at 8 TeV and also perform a first comparison with early ATLAS measurements at 13 TeV.

Pentaquark Baryons in String Theory -- Talk at Pentaquark 04

Pentaquark baryons $Θ^{+}$ and $Ξ^{--}$ are studied in the dual gravity theory of QCD in which simple mass formulae of pentaquarks are derived in the Maldacena prototype model for supersymmetric QCD and a more realistic model for ordinary QCD. In this approach it is possible to explain the extremely narrow decay widths of pentaquarks. With the aim of constructing more reliable mass formulae, a sketch is given on spin and the hyperfine interaction in the string picture.

Review: Status of the Standard Model

This talk summarizes topical theoretical work for tests of the electroweak theory and reviews the status of the electroweak Standard Model in view of the recent precision data reported at the 1997 summer conferences.

The Status of Lattice QCD at Finite Temperature

The status of lattice QCD investigations at high temperature is reviewed. After a short introduction into thermal QCD on the lattice we report on the present understanding of the phase diagram and the equation of state, in particular in presence of dynamical quarks. We continue with a discussion of various screening lengths in the plasma phase including results from dimensionally reduced QCD. This is followed by summarizing lattice data on quark number susceptibilities and spectral densities, both of which are of immediate relevance to the interpretation of heavy ion experiments. A major secti…

QCD and High Energy Interactions: Moriond 2016 Theory Summary

I summarize the theory talks presented at the 50 year anniversary conference. The talks covered a wide range of topics, but common threads included next-to-next-to-leading order predictions for many 2 -> 2 processes, beyond QCD lattice simulations, work on the set of persistent flavor physics anomalies, and discussions of the significance and possible explanations of the diphoton excess at 750 GeV.

Present Status of Lattice QCD at nonzero T and μ

I review a few selected topics in Lattice Quantum Chromo Dynamics, focusing more on the recent results. These include i) the equation of state and speed of sound, ii) J/ψsuppression, iii) flavour correlations and iv) the QCD phase diagram in the μ-T plane.

CGC, QCD Saturation and RHIC data (Kharzeev-Levin-McLerran-Nardi point of view)

This is the talk given at the Workshop:"Focus on Multiplicitioes", Bari, Italy, 17-19 June,2004.. In this talk, we are going to discuss ion-ion and deuteron - nucleus RHIC data and show that they support, if not more, the idea of the new QCD phase: colour glass condensate with saturated parton density. .

High energy scattering in QCD: dipole approach with Pomeron loops

This is the talk given at ``Gribov-75 Memorial Workshop on Quarks, Hadrons, and Strong Interactions", May 22-24, 2005, Budapest. Hungary. In this talk we discuss the BFKL Pomeron Calculus and its interrelation with thecolour dipole approach. The two key problems we consider are the probabilistic interpretation of the BFKL Pomeron Calculus and the possiblescenario for the asymptotic behaviour of the scattering amplitude at high energyin QCD.

Evolution equations for high parton density QCD

This talk is given at "Continious Advances in QCD", Minnesota, April 16-19,1998. It is a brief report on our results in high parton density QCD. The main goal of this talk is to discuss the new evolution equation which was obtained and solved by A.Ayala, M. Ducati and E.Levin and by E. Gotsman, E. Levin and U. Maor, and to share with you the physics can be recovered by this equation.

Hadron properties from QCD bound-state equations: A status report

Employing an approach based on the Green functions of Landau-gauge QCD, some selected results from a calculation of meson and baryon properties are presented. A rainbow-ladder truncation to the quark Dyson-Schwinger equation is used to arrive at a unified description of mesons and baryons by solving Bethe-Salpeter and covariant Faddeev equations, respectively.

Lattice QCD Calculations with b Quarks: Status and Prospects

This talk gives an overview of how lattice QCD calculations are influencing quark flavor physics. The first part of the talk focuses on the climb to higher precision; the second part surveys views along less-trodden paths.

Theoretical Status of Pentaquarks

We review the current status of the theoretical pentaquark search from the direct QCD calculation. The works from the QCD sum rule and the lattice QCD in the literature are carefully examined. The importance of the framework which can distinguish the exotic pentaquark state (if any) from the NK scattering state is emphasized.

Lattice QCD at finite temperature : present status

I review recent progress in finite temperature lattice calculations, including calculations of Equation of State, fluctuations of conserved charges and spatial correlation functions. I compare lattice results with the predictions of hadron resonance gas model, resummed perturbation theory and 3-dimensional effective field theory. Comparison of the lattice results for certain ratios with the prediction of AdS/CFT correspondence is also discussed.

Prospects of LHC Higgs Physics at the end of Run III - Talk presented at the International Workshop on Future Linear Colliders (LCWS2016), Morioka, Japan, 5-9 December 2016. C16-12-05.4

The document is prepared for the LCWS2016 conference proceedings. The expected status of Higgs physics at the end of Run-3 is presented. The current Run-2 status is briefly reviewed, and the expected Higgs reach after the HL-LHC period is also summarized for some channels.

Review of Theoretical Status: the Long and Short of High Energy Jets

High energy jets and their associated event shapes provide a window into the transition between elementary and composite degrees of freedom in quantum chromodynamics. This talk reviews some methods and a few principles that have led to progress in this area.

QCD At Moderately Large Distances

Invited talk at European Workshop on the QCD Structure of the Nucleon (QCD-N\'02), Ferrara, Italy, 3--6 Apr 2002

Status of Lattice Studies of the QCD Phase Diagram

Determining the QCD phase diagram is a pressing task in view of its relevance for nuclear and astro-particle physics programmes. We review the current status of lattice calculations of the phase diagram in the (T,μ_B)-plane for baryon chemical potentials μ_B < 500 MeV. At μ_B=0, simulations of staggered fermion actions predict the quark hadron transition to be a crossover in the continuum limit. As a baryon chemical potential is turned on, there is mounting evidence on coarse lattices for the crossover to weaken, rather than turning into a true phase transition at a critical point, as predicte…

Theoretical summary of Moriond 2022: QCD and high-energy interactions

I review theoretical talks presented at the session on QCD and high-energy interactions of the Moriond 2022 conference.

Status of Global QCD Analysis and the Parton Structure of the Nucleon

The current status of global QCD analysis of parton distribution functions of the nucleon is reviewed. Recent progress made in determining various features of the parton structure of the nucleon, as well as outstanding open questions are discussed. These include: the small-$x$ and large-$x$ behavior of the partons, particularly the gluon; the differentiation of $u$ and $d$ quarks; the strangeness sea ($s+\bar{s}$), the strangeness asymmetry ($s-\bar{s}$); and the heavy quark distributions $c$ and $b$. Important issues about assessing the uncertainties of parton distributions and their physical…

Pentaquarks: Status and Perspectives for Lattice Calculations

The present status of pentaquark spectroscopy in lattice QCD is reviewed. This talk also includes a brief introduction of pentaquark baryons.

DIS 2009 Concluding Talk: Outlook and Perspective

I will present here my perception on the status of Deep Inelastic Scattering physics, as I have further developed it during this Workshop, together with a number of comments on the results that have impressed me most during this week. I will emphasize a number of open problems and of critical areas. Finally I conclude with some projections and auspices for the future of the field.

QCD Potential and ttbar Threshold Cross Section --- Status Report ---

We include the full second-order corrections to the static QCD potential in the analysis of the ttbar threshold cross section. Then we examine the difference between the results obtained in the momentum-space approach and in the coordinate-space approach, which was found recently. Contrary to our expectation, the reduction of the difference by the inclusion of the second-order corrections is very small. There still remains a non-negligible deviation, which originates from the difference in the construction of the potentials in the two spaces. We scrutinize this problem. In particular, we estim…

Status of Spin Physics - Experimental Summary

The current status of spin physics experiments, based on talks presented at the Third Circum-Pan-Pacific Symposium on High Energy Spin Physics held in Beijing, 2001, is summarized in this article. Highlights of recent experimental results at SLAC, JLab, and DESY, as well as future plans at these facilities and at RHIC-spin are discussed.

Status of NNLO QCD corrections for process with one or more jets in the final state at the LHC

The abundant amount of data to be collected by the ATLAS and CMS collaborations in future runs of the Large Hadron Collider at CERN opens up a new era of precision physics. Some of the most prominent precision observables are related to processes with one or more jets in the final state. In order to fully exploit the potential of the LHC and the HL-LHC, it is imperative to make theoretical predictions at the level of accuracy that matches or even exceeds that of the upcoming measurements. In this talk we present a review of the status of theoretical predictions including NNLO QCD corrections f…

Moriond QCD 2017: theoretical summary

I summarize the highlights of the theory talks at the 52nd Rencontres de Moriond: QCD and high energy interactions.

QCD Sum Rules: The Second Decade

Invited Talk at the Conference "QCD -- 20 Years Later", June 9 - 13, 1992, Aachen, Germany

GENEVA蒙特卡洛：现状与新进展

GENEVA Monte Carlo: status and new developments

本研究综述了整合三种QCD精确预测理论工具的GENEVA蒙特卡洛框架，介绍其主要特性并阐述色单态产生、重色部分子与喷注末态产生相关的新改进。

On the effective Hamiltonian for QCD: An overview and status report

The session on effective Hamiltonians and chiral dynamics is overviewed, combined with a review on the bound-state problem. The progress during this session allows to remove all dependence on regularization in an effective interaction, thus to renormalize a Hamiltonian for the first time, and to solve front form as if they were instant-form equations, with all the advantages implied.

Soft Pomeron in QCD

This is a talk, given at Diffraction'2000, Sept. 2 - 7, Centraro, Italy. This talk is a brief presentation of our view on the Pomeron, as a non-perturbative QCD phenomenon but from sufficiently short distances. Our approach is based on the scale anomaly of QCD and emphasizes the r{ô}le of semi-classical QCD vacuum fields. We show that both the intercept and the slope of Pomeron trajectory appear to be determined by the energy density of non-perturbative QCD vacuum. The particular example of semi-classical QCD vacuum fields is discussed based on a new type of instanton-induced interactions (``i…

Applications of higher order QCD

In this talk we summarize some recent developments in perturbative QCD and their application to particle physics phenomenology.