B-meson Nuclear Modification Factor and $\mathbf{v_2(p_T)}$ in a Strongly Coupled Plasma in $\mathbf{Pb+Pb}$ Collisions at $\mathbf{\sqrt{s_{NN}}=2.76}$ TeV and $\mathbf{\sqrt{s_{NN}}=5.5}$ TeV

Open-beauty production in $p$Pb collisions at $\sqrt{s_{NN}}$=5 TeV: effect of the gluon nuclear densities

We present our results on open beauty production in proton-nucleus collisions for the recent LHC $p$Pb run at $\sqrt{s_{NN}}$=5 TeV. We have analysed the effect of the modification of the gluon PDFs in nucleus at the level of the nuclear modification factor. Because of the absence of measurement in $pp$ collisions at the same energy, we also propose the study of the forward-to-backward yield ratio in which the unknown proton-proton yield cancel. Our results are compared with the data obtained by LHCb collaboration and show a good agreement.

Impact of the Nuclear Modification of the Gluon Densities on J/Psi production in pPb collisions at sqrt(s_NN) = 5 TeV

We update our previous studies of nuclear-matter effects on J/Psi production in proton-nucleus for the recent LHC pPb runs at sqrt(s_NN)=5 TeV. We have analysed the effects of the modification of the gluon PDFs in nucleus, using an exact kinematics for a 2->2 process, namely g+g->J/Psi+g as expected from LO pQCD. This allows to constrain the transverse-momentum while computing the nuclear modification factor for different rapidities, unlike with the usual simplified kinematics. Owing to the absence of measurement in pp collisions at the same sqrt(s_NN) and owing to the expected significant unc…

Possibility for $J/Ψ$ suppression in high multiplicity proton-proton collisions at $\sqrt{s_{NN}}=7\,$TeV

We study $J/Ψ$ absorption in high multiplicity proton-proton (pp) collisions at $\sqrt {s_{NN}}=7\,$TeV. We predict a modification of the $J/Ψ$-yield within the UrQMD transport approach, where explicit interactions of the $J/Ψ$ with the surrounding comovers and a prehadronic phase with adjusted cross sections and $J/Ψ$ melting is included. We present the analog of the nuclear modification factor in pp collisions at various charged particle multiplicities. It turns out that $J/Ψ$-Mesons may be suppressed towards higher particle multiplicities in pp collisions at LHC energies.

Transverse Momentum Spectra and Nuclear Modification Factor using Boltzmann Transport Equation with Flow in Pb+Pb collisions at $\sqrt{s_{NN}}$ = 2.76 TeV

In the continuation of our previous work, the transverse momentum ($p_T$) spectra and nuclear modification factor ($R_{AA}$) are derived using relaxation time approximation of Boltzmann Transport Equation (BTE). The initial $p_T$-distribution used to describe $p+p$ collisions has been studied with the pQCD inspired power-law distribution, the Hagedorn's empirical formula and with the Tsallis non-extensive statistical distribution. The non-extensive Tsallis distribution is observed to describe the complete range of the transverse momentum spectra. The Boltzmann-Gibbs Blast Wave (BGBW) distribut…

Study of nuclear modification factors of (anti-)hadrons and light (anti-)nuclei in Pb-Pb collisions at $\sqrt{s_{\rm{NN}}}$ = 2.76 TeV

The nuclear modification factors ($R_{AA}$) of $π^{\pm}, p(\bar p)$, and $d(\bar d)$ with $|y|<0.5, p_T<20.0$~GeV/c in peripheral (40-60\%) and central (0-5\%) Pb-Pb collisions at $\sqrt {s_{NN}}=2.76$ TeV have been studied using the parton and hadron cascade ({\footnotesize PACIAE}) model plus the dynamically constrained phase space coalescence ({\footnotesize DCPC}) model. It is found that the $R_{AA}$ of light (anti)nuclei ($d, \bar d$) is similar to that of hadrons ($π^\pm, p, \bar p$), and the $R_{AA}$ of antiparticles is the same as that of particles. The suppression of $R_{AA}$ at high-…

未来强子对撞机中 $\mathbf{W^\pm W^\pm jj}$ 过程对纵向矢量玻色子散射与双荷希格斯玻色子产生的灵敏度

Sensitivity to longitudinal vector boson scattering and doubly-charged Higgs boson production in $\mathbf{W^\pm W^\pm jj}$ at future hadron colliders

基于 Delphes 框架的 FCC-hh 探测器参数化，研究未来 27-100 TeV $pp$ 对撞机中 $\mathbf{W^\pm W^\pm jj}$ 事件对纵向矢量玻色子散射及双荷希格斯玻色子产生的预期灵敏度与限制。

MSSM with $m_{h}=125$ GeV in High-Scale Gauge Mediation

After the discovery of SM-like Higgs with $m_{h}=125$ GeV, it is increasingly urgent to explore a solution to the hierarchy problem. In the context of MSSM from gauge-mediated SUSY breaking, the lower bound on gluino mass suggests that the messenger scale $M$ is probably large if the magnitude of $Λ\sim 100$ TeV. In this paper, we study $\overline{\mathbf{5}}+ \mathbf{5}$ model with $M\sim 10^{8}-10^{12}$ GeV and $Λ\simeq 100$ TeV. For moderate Higgs-messenger coupling, it will be shown a viable model with moderate fine tuning. In this model, $μ\sim 800$ GeV and $B_μ$ nearly vanishes at input …

Medium modification of photon-tagged and inclusive jets in high-multiplicity proton-proton collisions

We study modification of the photon-tagged and inclusive jets in $pp$ collisions at $\sqrt{s}=7$ TeV due to mini-quark-gluon plasma which can be produced in high multiplicity events. We show that for underlying events with $dN_{ch}/dη\sim 20-60$ the medium effects lead to a considerable modification of the photon-tagged and inclusive jet fragmentation functions. For inclusive jets the magnitude of the effect is surprisingly large. The effect is quite strong even for typical underlying events. We find that at $\sqrt{s}=7$ TeV the spectrum of charged hadrons is suppressed by $\sim 35-40$ % at $p…

核修正因子 $I_{AA}$ 在RHIC和LHC能量下 $AA$ 碰撞中，考虑 $pp$ 碰撞有无夸克-胶子等离子体形成的场景

Nuclear modification factor $I_{AA}$ in $AA$ collisions at RHIC and LHC energies in scenarios with and without quark-gluon plasma formation in $pp$ collisions

本文计算了RHIC和LHC能量下AA碰撞中的核修正因子$I_{AA}$，比较有无夸克-胶子等离子体形成的场景，预测7 TeV O+O碰撞结果，并指出测量$I_{OO}$可揭示$pp$碰撞中的喷注淬火现象。

$\mathbf{D_s}$-Meson as Quantitative Probe of Diffusion and Hadronization in Nuclear Collisions

The modifications of $D_s$-meson spectra in ultrarelativistic heavy-ion collisions are identified as a quantitative probe of key properties of the hot nuclear medium. This is enabled by the unique valence-quark content of the $D_s$=$c\bar{s}$ which couples the well-known strangeness enhancement with the collective-flow pattern of primordially produced charm quarks. We employ a consistent strong-coupling treatment with hydrodynamic bulk evolution and nonperturbative $T$-matrix interactions for both heavy-quark diffusion and hadronization in the Quark-Gluon Plasma (QGP). A large enhancement of t…

Quarkonia suppression in PbPb collisions at $\sqrt{s_{NN}}$ = 2.76 TeV

We estimate the modification of quarkonia yields due to different processes in the medium produced in Pb+Pb collisions at LHC energy. The quarkonia and heavy flavour cross sections calculated up to next-to-leading order (NLO) are used in the study. Shadowing corrections are obtained with the NLO EPS09 parametrization. A kinetic model is employed which incorporates quarkonia suppression inside a QGP, suppression due to hadronic comovers, and regeneration from charm pairs. The quarkonia dissociation cross section due to gluon collisions has been considered and the regeneration rate has been obta…

Leading order pQCD hadron production and nuclear modification factors at RHIC and the LHC

Hadron production in leading order pQCD is reviewed. The shape of the single inclusive particle spectra is well described for $p_T \geq 2-3$ GeV at center of mass energies from 20 GeV to 2 TeV. The phenomenological K-factor is found to decrease systematically with $\sqrt{s}$. For ultra-relativistic heavy ion reactions the calculation is augmented with the effects of initial multiple parton scattering and final state radiative energy loss. Baseline CERN-LHC predictions for hadron production in $p+p$ and suppression in central $Pb+Pb$ reactions at $\sqrt{s} = 5.5$ TeV are given in comparison to …