Related papers: Nuclear Effects in High Energy Photon and Neutral …
The intrinsic transverse momentum distribution of partons in the nucleon can be used to explain a large amount of high-$p_T$ hadron and photon production data in high-energy nucleon-nucleon collisions at energies $\sqrt{s} \approx 20$ to…
Pion and photon production cross sections are analyzed in proton-proton and proton-nucleus collisions at energies 20 GeV < s^1/2 < 60 GeV. We separate the proton-proton and nuclear contributions to transverse-momentum broadening and suggest…
We calculate the photon production cross section arising from the hard scattering of partons in nucleon-nucleon collisions by taking into account the intrinsic parton transverse momentum distribution and the next-to-leading-order…
We analyzed the transverse momentum spectra of positively and negatively charged pions ($\pi^+$ and $\pi^-$), positively and negatively charged kaons ($K^+$ and $K^-$), protons and antiprotons ($p$ and $\bar p$), as well as $\phi$ produced…
We calculate prompt photon production in high-energy nuclear collisions. We focus on the broadening of the intrinsic transverse momenta of the partons in the initial state from nuclear effects, and their influence on the prompt photon p_t…
The inclusive A(gamma,pi+ pi-)X reaction is studied theoretically. A sizeable enhancement of the cross section is found, in comparison with the scaling of the deuteron cross section (sigma_deuteron * A/2). This enhancement is due to the…
We predict a strong enhancement of multijet production in proton-nucleus collisions at collider energies, as compared to a naive expectation of a cross section $\propto A$. The study of the process would allow to measure, for the first…
The use of nuclear transparency effect of \pi^{-}-mesons in proton, and deuteron induced interactions with carbon nuclei at 4.2A GeV/c, to get information about the properties of nuclear matter, is presented in this work. Half angle…
The relationship between the parton transverse momentum and longitudinal momentum, which is obtained by analysing the hadron tensor in the deep inelastic scattering (DIS) process, indicates that the transverse size of partons in a nucleon…
We present results on the production of direct photons, pizero, and eta mesons on nuclear targets at large transverse momenta (p_T). The data are from 530 and 800 GeV/c proton beams and 515 GeV/c piminus beams incident upon copper and…
Recently claimed \cite{dj1,dj2,FC} anomalous nuclear effects in di-jet production are analyzed in view of multiple interaction of projectile/ejectile partons in nuclear matter. We derive model--independent relations between A-dependence of…
The strong electromagnetic fields in peripheral heavy ion collisions give rise to photon-photon and photon-nucleus interactions. I present a general survey of the photon-photon and photon-hadron physics accessible in these collisions. Among…
We present an exploratory study using generalized parton distributions of several observables related to transverse degrees of freedom in hadronic structure -- the nucleon transverse momentum, the transverse radius, or impact parameter, and…
In the wounded nucleon model, a proton-nucleus (p+A) collision is a superposition of independent nucleon-nucleon collisions. We use this model to calculate the average transverse momentum of pions, kaons and protons in high energy p+A…
We calculate the photon production cross-section in $pA$ collisions under the assumption that the nucleus has reached the saturation regime, while the proton can be described by the standard parton distribution functions. We show that due…
We discuss the unexpected enhancement of the $N^*$ electroproduction on nuclei recently observed in the $(\gamma^*,p\pi^-)$ measurement. A mechanism which is able to explain this result is proposed. To clarify the situation, we suggest to…
Determining the inner structure of protons and nuclei in terms of their fundamental constituents has been one of the main tasks of high energy nuclear and particle physics experiments. This quest started as a mapping of the (average) parton…
We study the nuclear enhancement of the transverse momentum imbalance for back-to-back particle production in both p+A and e+A collisions. Specifically, we present results for photon+jet and photon+hadron production in p+A collisions,…
We evaluate the transverse momentum spectrum of J/Psi (up to semi-hard momenta) in pA and AA collisions taking into account only the initial state effects, but resumming them to all orders in \alpha_s^2 A^{1/3}. In our previous papers we…
The transverse momentum (pt) dependence of J/psi production in heavy ion collisions is investigated in a transport model with both initial production and continuous regeneration of charmonia. The competition between the two production…