We compute the three-loop master integrals required for the calculation of the triple-real contribution to the N$^3$LO quark beam function due to the splitting of a quark into a virtual quark and three collinear gluons, $q \to q^*+ggg$. This provides an important ingredient for the calculation of the leading-color contribution to the quark beam function at N$^3$LO.
Revised formulas for the inclusive cross section of a triple parton scattering process in a hadron collision are suggested basing on the modified collinear three-parton distributions. The possible phenomenological issues are discussed.
The triple pomeron interaction is studied in the perturbative approach of BFKL-Bartels. At finite momentum transfers $\sqrt{-t}$ the contribution factorizes in the standard manner with a triple-pomeron vertex proportional to $1/\sqrt{-t}$. At $t=0$ the contribution is finite, although it grows faster with energy than for finite $t$ and does not factorize.
We study NLO QCD corrections as relevant to hadronic W decay in W pair production at a future 500 GeV electron-positron linac, with particular emphasis on the determination of triple gauge boson vertices. We find that hard gluon bremstrahlung may mimic signatures of anomalous triple gauge boson vertices in certain distributions. The size of these effects can strongly depend on the polarisation of the initial electron positron beams.
We estimate the size of the triple Pomeron vertex in perturbative QCD and compare with the phenomenological value extracted from Regge fits to experimental data. For simplicity, the results of the QCD analysis are taken in the large-N_c limit. We find that the perturbative triple Pomeron coupling is of the same order of magnitude as the observed one. We also estimate the size of the Pomeron self energy and its contribution to the renormalization of the Pomeron intercept. The effect is very small, in agreement with previous nonperturbative estimates.
We investigate the high energy behavior of QCD for different surface topologies of color graphs. After a brief review of the planar limit (bootstrap and gluon reggeization) and of the cylinder topology (BFKL) we investigate the 3 -> 3 scattering in the triple Regge limit which belongs to the pair-of-pants topology. We re-derive the triple Pomeron vertex function and show that it belongs to a specific set of graphs in color space which we identify as the analogue of the Mandelstam diagram.
We study the factorisation properties of one-loop scattering amplitudes in the triple collinear limit and extract the universal splitting amplitudes for processes initiated by a gluon. The splitting amplitudes are derived from the analytic Higgs plus four partons amplitudes. We present compact results for primitive helicity splitting amplitudes making use of super-symmetric decompositions. The universality of the collinear factorisation is checked numerically against the full colour six parton squared matrix elements.
We compute the O(alpha_s) QCD corrections to charged triple vector boson production at a hadron collider, i.e. the processes pp -> ZZW + X and pp -> WWW + X. Intermediate Higgs boson exchange effects, spin correlations from leptonic vector boson decays, and off-shell contributions are all taken into account. Results are implemented in a fully flexible Monte Carlo program that allows for an easy customization of kinematical cuts and variation of the factorization and renormalization scales. We analyze the dependence of the differential cross sections under scale variations and present distribut…
We provide results for the one-loop triple-collinear color/spin-space splitting operators for the five possible processes, $q \to qq'\bar{q}'$, $q \to qq\bar{q}$, $q \to qgg$, $g \to gq\bar{q}$ and $g \to ggg$. The expressions are exact in dimensionally-regulated massless QCD up to a single integral, which we expand to second order in the dimensional-regularisation parameter. We also evaluate the related splitting functions. Our results are both sufficient and indispensable for the construction of subtraction and integrated-subtraction terms for triple-collinear singularities of one-loop doubl…
Single and double inclusive cross-sections for gluon jet production from within the triple pomeron vertex are studied in the reggeized gluon technique. It is shown that to satisfy the AGK rules the vertex has to be fully symmetric in all four reggeized gluons which form the two final pomerons. The single inclusive cross-sections are found for different cuttings of the triple pomeron vertex. They sum into the expression obtained by Yu.Kovchegov and K.Tuchin in the colour dipole picture. The found double inclusive cross-sections satisfy the AGK rules.
We consider the singular behaviour of one-loop QCD matrix elements when several external partons become simultaneously parallel. We present a new factorization formula that describes the singular collinear behaviour directly in colour space. The collinear singularities are embodied in process-independent splitting matrices that depend on the momenta, flavours, spins and colours of the collinear partons. We give the general structure of the infrared and ultraviolet divergences of the one-loop splitting matrices. We also present explicit one-loop results for the triple collinear splitting, $q \t…
The prospects of measuring triple gauge couplings in W pair production at future linear colliders with transverse beam polarisation are studied. We consider CP conserving and CP violating couplings with both real and imaginary parts. The maximum achievable sensitivity in a simultaneous measurement of all couplings is determined using optimal observables, extending an earlier analysis for longitudinal beam polarisation. We find good sensitivity to the coupling Im(g^R_1 + kappa_R), which is not measurable with longitudinal polarisation. In contrast, for the real parts (including the CP violating…
In this work we analyse the triple Higgs boson production cross section at hadron colliders via gluon fusion, and present for the first time the full set of QCD NNLO corrections in the heavy top limit. In order to account for finite top mass effects we perform two different reweighting procedures, and study the dependence of the result on the choice of the approximation. Combining the most accurate predictions available to date, we present the following result for the total NNLO cross section for triple Higgs boson production at a 100 TeV collider: $σ_\text{NNLO}=5.56^{+5\%}_{-6\%} \pm 20\%$ f…
Using the recent solution of the triple Pomeron coupling in the QCD dipole picture as a closed string amplitude with six legs, its analytical form in terms of hypergeometric functions and numerical value are derived.
In a previous publication, we have constructed a set of non-linear evolution equations for dipole scattering amplitudes in QCD at high energy, which extends the Balitsky-JIMWLK hierarchy by including the effects of fluctuations in the gluon number in the target wavefunction. In doing so, we have relied on the color dipole picture, valid in the limit where the number of colors is large, and we have made some further approximations on the relation between scattering amplitudes and dipole densities, which amount to neglecting the non-locality of the two-gluon exchanges. In this Letter, we relax t…
We study integrations over light-cone momenta in the gauge invariant effective action of high energy QCD. A regularization mechanism which allows for the evaluation of the longitudinal integrations is presented. After a rederivation of the reggeized gluon and the BFKL-equation from the effective action, we study the 1-3 and 2-4 reggeized gluon transition vertex of QCD Reggeon field theory and discuss their connection with the usual triple Pomeron vertex of perturbative QCD.
We present a calculation of the next-to-leading-order QCD and electroweak corrections to WWW production with leptonically decaying $\mathrm{W}$ bosons at the LHC, fully taking into account off-shell contributions, intermediary resonances, and spin correlations. The contributions of the quark-antiquark-induced electroweak correction to typical fiducial cross sections at the LHC are of the order of 5-8% and grow to tens of percent in the high-energy tails of distributions. We observe strong cancellations among the positive quark-photon and negative quark-antiquark-induced electroweak corrections…
The appearance of the triangle graph infra-red axial anomaly in reduced quark loops contributing to QCD triple-regge interactions is studied. In a dispersion relation formalism, the anomaly can only be present in the contributions of unphysical triple discontinuities. In this paper an asymptotic discontinuity analysis is applied to high-order feynman diagrams to show that the anomaly does indeed occur in sufficiently high-order reggeized gluon interactions. The reggeon states involved must contain reggeized gluon combinations with the quantum numbers of the anomaly (winding-number) current. A …
In a previous paper it has been shown that the infra-red divergence associated with the triangle graph axial anomaly can occur in triple-regge multi-reggeon interactions due to unphysical asymptotic triple discontinuities. In this paper an asymptotic discontinuity analysis is applied to high-order feynman diagrams to show that the anomaly exists in contributions to the triple-regge nine-reggeon interaction. This implies that the anomaly occurs in the interactions of reggeon states that have the quantum numbers of the anomaly current and establishes a direct connection with the well-known U(1) …
In this work, some of the NLO QCD corrections for pp -> VVjj + X are presented. A program in Mathematica based on the structure of FeynCalc which automatically simplifies a set of amplitudes up to the hexagon level of rank 5 has been created for this purpose. We focus on two different topologies. The first involves all the virtual contributions needed for quadruple electroweak vector boson production, i.e. pp -> VVVV + X. In the second, the remaining "bosonic" corrections to electroweak triple vector boson production with an additional jet (pp -> VVV j + X) are computed. We show the factorizat…
We consider the radiation of three soft gluons in a generic process for multiparton hard scattering in QCD. In the soft limit the corresponding scattering amplitude has a singular behaviour that is factorized and controlled by a colorful soft current. We compute the tree-level current for triple soft-gluon emission from both massless and massive hard partons. The three-gluon current is expressed in terms of maximally non-abelian irreducible correlations. We compute the soft behaviour of squared amplitudes and the colour correlations produced by the squared current. The radiation of one and two…
We show that an anomalous CP-violating gamma-gamma-Z vertex gives rise to a novel asymmetry with transversely polarized electron and positron beams in the process e+e- -> gamma Z. This asymmetry, which is odd under naive time reversal, is proportional to the real part of the gamma-gamma-Z CP-violating coupling. This is in contrast to the simple forward-backward asymmetry of the gamma (or Z) with unpolarized or longitudinally polarized beams studied earlier, which is even under naive time reversal, and is proportional to the imaginary part. We estimate the sensitivity of future experiments to t…
We compute the master integrals required for the calculation of the double-real emission contributions to the matching coefficients of 0-jettiness beam functions at next-to-next-to-next-to-leading order in perturbative QCD. As an application, we combine these integrals and derive the double-real gluon emission contribution to the matching coefficient $I_{qq}(t,z)$ of the quark beam function.
I show that factorization for hard processes in QCD is also valid when the detected particles are polarized, and that the proof of the theorem determines the operator form for the parton densities. Particular attention is given to the case of transversely polarized incoming hadrons.
We report on preliminary results for the triple-gluon and the quark-gluon vertex in Landau gauge. Our results are based on two-flavor and quenched lattice QCD calculations for different quark masses, lattice spacings and volumes. We discuss the momentum dependence of some of the vertices's form factors and the deviations from the tree-level form.
We consider the radiation of three soft gluons in a generic process for multiparton hard scattering in QCD. In the soft limit the corresponding scattering amplitude has a singular behaviour that is factorized and controlled by a colorful soft current. We compute the tree-level current for triple soft-gluon emission from both massless and massive hard partons. The three-gluon current is expressed in terms of maximally non-abelian irreducible correlations. We compute the soft behaviour of squared amplitudes and the colour correlations produced by the squared current. The radiation of one and two…
We obtain analytic results for integrated triple-collinear splitting functions that emerge as collinear counter-terms in the context of the nested soft-collinear subtraction scheme arXiv:1702.01352 . With these results, all integrated subtraction terms required for NNLO QCD computations within this scheme are known analytically. In addition to improving efficiency and numerical stability of practical computations, the availability of these results will contribute towards establishing a general NNLO QCD subtraction formula for generic hard scattering processes in hadron collisions, similar to C…
We study integrations over light-cone momenta in the high energy effective action of QCD. After a review of the effective action, we arrive on a regularization mechanism from matching with QCD diagrams, which we apply to a re-derivation of the reggeized gluon and of the BFKL-equation. We study consequences of the proposed regularization on the analytic structure of 2->3 and 2->4 production amplitudes in the Multi-Regge-Kinematics. We derive a certain part of the 1-loop corrections to the production vertex and demonstrate that they yield the on-set of corrections demanded by the Steinmann-relat…
We present the matching coefficient for the quark beam function at next-to-next-to-next-to-leading order in perturbative QCD in the generalized large $N_c$-approximation, $N_c \sim N_f \gg 1$. Although several refinements are still needed to make this result interesting for phenomenological applications, our computation shows that a fully-differential description of simple color singlet production processes at a hadron collider at N$^3$LO in perturbative QCD is within reach.
The lowest order pomeron loop is calculated for the leading conformal weight with full dependence of the triple pomeron vertex on intermediate conformal weights. The loop is found to be convergent. Its contribution to the pomeron Green function begins to dominate already at rapidities 10$÷$15. The pomeron pole renormalization is found to be quite small due to a rapid fall of the triple pomeron vertex with rising conformal weights.
We present splitting functions in the triple collinear limit at next-to-leading order in the strong coupling. We performed the computation in the context of massless QCD+QED, and consider first collinear processes which include at least one photon. The IR divergent structure of the multi-partonic splitting functions agrees with the Catani's formula. Consistency checks based on symmetry arguments have been implemented and results for different configurations have been cross-checked. Studying photon-started processes, we obtained very compact results: this allowed us to simplify the expressions …
In this paper we compute the QCD corrections for the triple Higgs boson production cross section via gluon fusion, within the heavy-top approximation. We present, for the first time, analytical results for the next-to-leading order corrections, and also compute the soft and virtual contributions of the next-to-next-to-leading order cross section. We provide predictions for the total cross section and the triple Higgs invariant mass distribution. We find that the QCD corrections are large at both perturbative orders, and that the scale uncertainty is substantially reduced when the second order …
We examine the possibility of using single-Higgs production at an $e^+e^-$ collider with polarized beams to measure, or constrain, indirectly a possible anomalous triple-Higgs coupling, which can contribute to the process via one-loop diagrams. In the dominant process $e^+e^- \to ZH$, longitudinally polarized beams can lead to an improvement in the cross section by 50\% for $e^-$ and $e^+$ polarizations of $-0.8$ and $+0.3$, respectively. This corresponds to an improvement in the sensitivity to the triple-Higgs coupling of about 18\% for a centre-of-mass energy of 250 GeV and an integrated lum…
One of the main objectives of almost all future (lepton) colliders is to measure the self-coupling of triple Higgs in the Standard Model. By elongating the Standard Model's scalar sector, using incipient Higgs doublet along with a quadratic (Higgs) potential should reveal many incipient features of the model and the possibility of the emergence of additional Higgs self-couplings. The self-coupling of the Higgs boson helps in reconstructing the scalar potential. The main objective of this paper is to extract Higgs self-coupling by numerically analyzing several scattering processes governed by t…
We present a calculation of the O(alpha_s) QCD corrections to the production of a Z boson in association with two photons and to triple photon production at hadron colliders. All final-state photons are taken as real. For the Z boson, we consider the decays both into charged leptons and into neutrinos including all off-shell effects. Numerical results are obtained via a Monte Carlo program based on the structure of the VBFNLO program package. This allows us to implement general cuts and distributions of the final-state particles. We find that the NLO QCD corrections are sizable and significant…
We argue that features of hadron production in relativistic nuclear collisions, mainly at CERN-SPS energies, may be explained by the existence of three forms of matter: Hadronic Matter, Quarkyonic Matter, and a Quark-Gluon Plasma. We suggest that these meet at a triple point in the QCD phase diagram. Some of the features explained, both qualitatively and semi-quantitatively, include the curve for the decoupling of chemical equilibrium, along with the non-monotonic behavior of strange particle multiplicity ratios at center of mass energies near 10 GeV. If the transition(s) between the three pha…
Diboson production processes are of great importance in high-energy physics and a precise theoretical knowledge of VV production is mandatory not only in view of precision tests of the Standard Model but also in the one of new physics searches. We present results of arXiv:1804.01477, where we computed the NLO QCD and NLO electroweak corrections to diboson production processes at the LHC including the effect of the anomalous triple-gauge-boson interactions at NLO QCD accuracy. The anomalous triple-gauge-boson interactions are parametrized in terms of higher-dimensional operators in the effectiv…
In this paper, we present the precision predictions for three photon production in the standard model (SM) at the ILC including the full next-to-leading (NLO) electroweak (EW) corrections, high order initial state radiation (h.o.ISR) contributions and beamstrahlung effects. We present the LO and the NLO EW+h.o.ISR+beamstrahlung corrected total cross sections for various colliding energy when $\sqrt s \ge 200 {\rm GeV}$ and the kinematic distributions of final photons with $\sqrt s = 500 {\rm GeV}$ at ILC, and find that the NLO EW corrections, the h.o.ISR contributions and the beamstrahlung eff…
We study the properties of the Triple Pomeron Vertex in the perturbative QCD using the twist expansion method. Such analysis allows us to find the momenta configurations preferred by the vertex. When the momentum transfer is zero, the dominant contribution in the limit when Nc goes to infty comes from anticollinear pole. This is in agreement with result obtained without expanding, but by direct averaging of the Triple Pomeron Vertex over angles. Resulting theta functions show that the anticollinear configuration is optimal for the vertex. In the finite Nc case the collinear term also contribut…
In this article, we study the triple-collinear limit of scattering amplitudes, focusing the discussion in processes which include at least one photon. To deal with infrared divergences we applied dimensional regularization (DREG) and we worked in the time-like (TL) kinematical region in order to ensure the validity of strict-collinear factorization. Both polarized and unpolarized splitting functions were obtained using independent codes, which allowed to implement a first cross-check among them. The divergent structure of all the triple-collinear splittings was compared with the Catani's formu…
We compute the two-loop master integrals required for the leading QCD corrections to the interaction vertex of a massive neutral boson $X^0$, e.g. $H,Z$ or $γ^{*}$, with a pair of $W$ bosons, mediated by a $SU(2)_L$ quark doublet composed of one massive and one massless flavor. All the external legs are allowed to have arbitrary invariant masses. The Magnus exponential is employed to identify a set of master integrals that, around $d=4$ space-time dimensions, obey a canonical system of differential equations. The canonical master integrals are given as a Taylor series in $ε= (4-d)/2$, up to or…
The basic theoretical milestones were the Sakata SU(3) symmetry, the Goldberg-Ne'eman composite model with SU(3) triplets having baryon number (1/3) and the Nambu color gauge Lagrangian. The transition was led in right and wrong directions by experiments interpreted by phenomenology. A "good" experiment on $\bar p p$ annihilation at rest showed that the Sakata model predictions disagreed with experiment. A "bad" experiment prevented the use of the Goldberg-Ne'eman triplet model to predict the existence and masses of the of the $Ξ^*$ and $Ω^-$. More "good" experiments revealed the existence and…
The anomalous trilinear gauge couplings of $Z$ and $γ$ are studied in $e^+e^-\to ZZ/Zγ$ with longitudinal beam polarizations using a complete set of polarization asymmetries for the $Z$ boson. We quantify the goodness of the beam polarization in terms of the likelihood and find the best-choice of $e^-$ and $e^+$ polarizations to be ($+0.16$, $-0.16$), ($+0.09$, $-0.10$) and ($+0.12$, $-0.12$) for $ZZ$, $Zγ$ and combined processes, respectively. Simultaneous limits on anomalous couplings are obtained for these choices of beam polarizations using Markov-Chain--Monte-Carlo (MCMC) for an $e^+e^-$ …
The Regge limit in perturbative QCD for processes as DIS (low x) and photon or onia-particles scattering is considered. In the first part a phenomenological approach for the inclusion of the running coupling, preserving the gluon reggeization property, is analyzed. In particular the spectrum of the hard pomeron equation and the asymptotic form of the solution are used to study scattering processes with also inclusive jet production. The singlet part of the proton structure function is evolved towards the low x region according to the full equation. In the second part the problem of unitarity i…
Diboson production is of prime interest at the LHC particularly due to its sensitivity to the gauge-boson self interaction, allowing to test its Standard Model prediction with high precision and to search for possible deviations with respect to the Standard Model. We report on the results of arXiv:1804.01477, where we computed WW, WZ and ZZ production (including the leptonic decays of the vector bosons) in the effective field theory framework at NLO QCD accuracy. The impact of the higher-dimensional operators is compared to the NLO QCD and NLO EW corrections in the Standard Model. Our calculat…
We present a calculation of all matching coefficients for $N$-jettiness beam functions at next-to-next-to-next-to-leading order (N$^3$LO) in perturbative quantum chromodynamics (QCD). Our computation is performed starting from the respective collinear splitting kernels, which we integrate using the axial gauge. We use reverse unitarity to map the relevant phase-space integrals to loop integrals, which allows us to employ multi-loop techniques including integration-by-parts identities and differential equations. We find a canonical basis and use an algorithm to establish non-trivial partial fra…
One of the most-studied signals for physics beyond the standard model in the production of gauge bosons in electron-positron collisions is that due to the anomalous triple gauge boson couplings in the $Z γ$ final state. In this work, we study the implications of this at the ILC with polarized beams for signals that go beyond traditional anomalous triple neutral gauge boson couplings. Here we report a dimension-8 CP-conserving $Z γZ$ vertex that has not found mention in the literature. We carry out a systematic study of the anomalous couplings in general terms and arrive at a classification. We…
We address $q q \bar Q\bar Q$ exotic tetraquark bound states and resonances with a fully unitarized and microscopic quark model. We propose a triple string flip-flop potential, inspired in lattice QCD tetraquarks static potentials and fluxtubes, combining meson-meson and tetraquark potentials. Our potential goes up to the color excited potential, but neglects spin-tensor potentials. To search for bound states and resonances, we first solve the two-body mesonic problem. Then we develop fully unitary techniques to address the four-body tetraquark problem. We fold the four-body Shcrödinger equati…
The amplitude for the collision of two hadrons with the lowest order pomeron loop is calculated. Numerical calculations show that the loop contribution to the amplitude begins to dominate the single pomeron exchange at rapidities 8-10. Full dependence of the triple-pomeron vertex on intermediate conformal weights is taken into account.
A hybrid model is presented for hadron polarization that is based on perturbative QCD subprocesses and the recombination of polarized quarks to form polarized hadrons. The model, originally applied to polarized $Λ$'s that were inclusively produced by proton beams, is extended to include pion beams and polarized $Λ_c$'s. The resulting polarizations are calculated as functions of $x_F$ and $p_T$ for high energies and are found to be in fair agreement with recent experiments.
I demonstrate how confinement in Coulomb-gauge QCD makes quark-quark states of the color anti-triplet (diquarks) move out of the physical spectrum. Mesons as color singlet quark-antiquark states, on the other hand have finite masses and for highly excited states in the meson spectra effective restoration of chiral symmetry can be observed.
One loop QCD corrections to hadronic W decay are calculated for arbitrary W polarizations . The results are applied to W pair production and decay at LEP200. We focus on the corrections to angular distributions with particular emphasis on azimuthal distributions and correlations. The relevance of our results to the experimental determination of possible nonstandard triple gauge bosons interactions is discussed.
Recent H1 data on triple differential dijet cross sections in $e^\pm p$ interactions in the region of low photon virtualities are shown to be in reasonable agreement with the predictions of the NLO QCD calculations obtained using the program NLOJET++. The implications of this observation for the phenomenological relevance of the concept of resolved virtual photon are discussed.
We study the cross-section of production of a single $W^-$ boson in association with a neutrino through the process $e^-p \to e^-γ^*p \to ν_eW^- p$. Additionally, we obtain the anomalous couplings $Δκ_γ$ and $λ_γ$ of the $W^+W^-γ$ vertex at the Large Hadron Electron Collider (LHeC) and the Future Circular Collider Hadron-Electron (FCC-he). The impact of the polarized beam due to the electron is also analyzed. Our best limits for $Δκ_γ$ and $λ_γ$ at the $95\%$ C.L. are: $Δκ_γ= \pm 0.0017$, $λ_γ= \pm 0.0053$ (unpolarized electron beam) and $Δκ_γ= \pm 0.0013$, $λ_γ= \pm 0.0046$ (polarized electro…
One of the most promising methods to search for axions is a light-shining-through-walls (LSW) experiment. In this work, we discuss the possibility of performing an LSW experiment at the ILC experiment, where photon beams are generated for positron production. The photon beam is energetic and intense; the energy is of order MeV and the number of photons is about $10^{24}$ per year. Due to the high energy and intensity, this LSW experiment can reveal the parameter region of the axion unexplored by previous ground-based experiments.
Triple Differential Heavy-to-light Semi-leptonic Decays at Next-to-Next-to-Next-to-Leading Order in QCD
School of Physics, Shandong University（山东大学物理学院）；Physik-Institut, Universität Zürich（苏黎世大学物理研究所）；SLAC National Accelerator Laboratory, Stanford University（斯坦福大学斯坦福直线加速器中心）；School of Physics, Peking University（北京大学物理学院）；Center for High Energy Physics, Peking University（北京大学高能物理中心）
We present numerical results for the two loop QCD corrections to the ghost gluon vertex, the quark gluon vertex, and the triple gluon vertex in the massless limit at the symmetric point. We restrict ourselves to the tensor structures existing in the tree level. The corrections are used to examine different coupling constant definitions in momentum subtraction schemes and the corresponding three-loop $β$ functions.
We calculate the triple gluon, ghost-gluon and quark-gluon vertex functions at two loops in the MSbar scheme in the chiral limit for an arbitrary linear covariant gauge when the external legs are all off-shell.
Triple-quark elastic scattering amplitudes from perturbative QCD are first calculated and then used in a transport equation to study the thermalization of quark matter. By examining momentum isotropy to which the transport equation leads, we can determine thermalization time and offer an initial thermal quark distribution function. With an anisotropic initial quark distribution, which is relevant to quark matter initially created in a central Au-Au collision at \sqrt {s_{NN}}=200 GeV, the transport equation gives a time of the order of 1.8 fm/c for quark matter itself to thermalize by the trip…
