In this work, we propose a method to show the correspondence between hadron and its quark component nuclear modification factors. A parton and hadron cascade model PACIAE based on the PYTHIA6.4 is employed to calculate the hadron and its quark compon
ent nuclear modification factors in the 0-5% most central $Pb+Pb$ collisions at $sqrt{s_{NN}}$=2.76 TeV. It turns out that the hadron nuclear modification factor is usually smaller than that of its quark component. On the other hand, it is shown in our study that the dead cone effect is more likely to be identified with the quarks and mesons but not with the baryon states obviously.
In this paper, production of ${rm W}^{pm}$ and ${rm Z}^{0}$ vector bosons in p-p, p-Pb (Pb-p), and Pb-Pb collisions at $sqrt{s_{rm NN}}=5.02$ TeV is dynamically simulated with a parton and hadron cascade model PACIAE. ALICE data of ${rm Z}^{0}$ produ
ction is found to be reproduced fairly well. A prediction for ${rm W}^{pm}$ production is given in the same collision systems, at the same energy and at the same energy. An interesting isospin-effect is observed in the sign-change of $mu^{pm}$ charge asymmetry in pp, pn, np, and nn collisions and in minimum bias p-Pb, Pb-p and Pb-Pb collisions at $sqrt{s_{rm NN}}=5.02$ TeV, respectively.
The production of strange particles $Xi_{c}^{+}, K^{-}$ is simulated in mid-rapidity $pp$ collisions at $sqrt{s}=7$ TeV with $0.2 leq pt leq 6$~GeV/c using the {footnotesize PACIAE} model. The results are consistent with LHCb experimental data on $Xi
_{c}^{+}$ and $K^{-}$ yield. Then, a dynamically constrained phase-space coalescence ({footnotesize DCPC}) model plus {footnotesize PACIAE} model was used to produce the $Xi_{c}^{+}K^{-}$ bound states and study the narrow excited $Omega_{c}^{0}$ states through $Omega_{c}^{0} to Xi_{c}^{+}K^{-}$ in $pp$ collisions at $sqrt{s}=7$ and 13 TeV. The yield, transverse momentum distribution, and rapidity distribution of the five new excited $Omega_{c}^{0}$ states of $Omega_{c}(3000)^{0}$, $Omega_{c}(3050)^{0}$, $Omega_{c}(3066)^{0}$,$Omega_{c}(3090)^{0}$and $Omega_{c}(3119)^{0}$ were predicted.
The parton and hadron cascade model PACIAE 2.1 (cf. Comput. Phys. Commun.184 (2013) 1476) has been upgraded to the new issue of PACIAE 2.2. By this new issue the lepton-nucleon and lepton-nucleus (inclusive) deep inelastic scatterings can also be inv
estigated. As an example, the PACIAE 2.2 model is enabled to calculate the specific charged hadron multiplicity in the $e^-$+p and $e^-$+D semi-inclusive deep-inelastic scattering at 27.6 GeV electron beam energy. The calculated results are well comparing with the corresponding HERMES data. Additionally, the effect of model parameters alpha and beta in the Lund string fragmentation function on the multiplicity is studied.
Based on the requirement in the simulation of lepton-nucleus deep inelastic scattering (DIS), we construct a fortran program LDCS 1.0 calculating the differential and total cross sections for the unpolarized charged lepton-unpolarized nucleon and neu
trino-unpolarized nucleon neutral current (charged current) DIS at leading order. Any set of the experimentally fitted parton distribution functions could be employed directly. The mass of incident and scattered leptons is taken into account and the boundary conditions calculating the single differential and total cross section are studied. The calculated results well agree with the corresponding experimental data which indicating the LDCS 1.0 program is good. It is also turned out that the effect of tauon mass is not negligible in the GeV energy level.
A dynamically constrained coalescence model based on the phase space quantization and classical limit method was proposed to investigate the production of light nuclei (anti-nuclei) in non-single diffractive (NSD) pp collisions at $sqrt{s}$=7 and 14
TeV. This calculation was based on the final hadronic state in the PYTHIA and PACIAE model simulations, the event sample consisted of 1.2$times 10^8$ events in both simulations. The PACIAE model calculated $bar D$ yield of 6.247$times 10^{-5}$ in NSD pp collisions at $sqrt{s}$=7 TeV is well comparing with the ALICE rough datum of 5.456$times 10^{-5}$. It indicated the reliability of proposed method in some extent. The yield, transverse momentum distribution, and rapidity distribution of the $bar D$, $^3{bar{He}}$, and $_{barLambda} ^3{bar H}$ in NSD pp collisions at $sqrt{s} $=7 and 14 TeV were predicted by PACIAE and PYTHIA model simulations. The yield resulted from PACIAE model simulations is larger than the one from PYTHIA model. This might reflect the role played by the parton and hadron rescatterings.
We have updated the parton and hadron cascade model PACIAE for the relativistic nuclear collisions, from based on JETSET 6.4 and PYTHIA 5.7 to based on PYTHIA 6.4, and renamed as PACIAE 2.0. The main physics concerning the stages of the parton initia
tion, parton rescattering, hadronization, and hadron rescattering were discussed. The structures of the programs were briefly explained. In addition, some calculated examples were compared with the experimental data. It turns out that this model (program) works well.
The parton and hadron cascade model PACIAE based on PYTHIA was used to investigate the charged particle elliptic flow in minimum bias pp collisions at the LHC energies. The strings were distributed randomly in the transverse ellipsoid of the pp colli
sion system with major axis of $R$ (proton radius) and minor axis of $R(1-xi)$ before parton rescattering. The charged particle elliptic flow as a function of the random number $xi$ and transverse momentum $p_T$ were investigated. The calculated $v_2/epsilon$ as a function of reaction energy increases monotonously with increasing reaction energy up to $sqrt{s}sim$7 TeV and then turns to saturation. With the parton-parton cross section enlarges three times in parton rescattering, the rapidity integrated charged particle elliptic flow may reach 0.025 at $p_T sim$2 GeV/c in the minimum bias pp collisions at $sqrt{s}$=7 TeV.
