We present a model for weak CC induced nuclear reactions at energies of interest for current and future neutrino oscillation experiments. This model is a natural extension of the work of Refs.[1,2], where the QE contribution to the inclusive electron and neutrino scattering on nuclei was analyzed. The model is based on a systematic many body expansion of the gauge boson absorption modes that includes one, two and even three body mechanisms, as well as the excitation of Delta isobars. The whole scheme has no free parameters, besides those previously adjusted to the weak pion production off the nucleon cross sections in the deuteron, since all nuclear effects were set up in previous studies of photon, electron and pion interactions with nuclei. We have discussed at length the recent charged current quasi-elastic MiniBooNE cross section data, and showed that two nucleon knockout mechanisms are essential to describe these measurements.
Single and double inclusive cross-sections in nucleus-nucleus collisions are derived in the perturbative QCD with interacting BFKL pomerons in the quasi-classical approximation.
We study single inclusive hadron production in proton-proton and proton-nucleus collisions in the CGC framework. The parameters in the calculation are determined solely by standard nuclear geometry and by electron-proton deep inelastic scattering data, which is fit using the running coupling BK equation. We show that it is possible to obtain a good fit of the HERA inclusive cross section also without an anomalous dimension in the initial condition. We argue that one must consistently use the proton transverse area as measured by a high virtuality probe in DIS also for the single inclusive cros…
Exploiting recently obtained analytic solutions of classical Yang-Mills equations for higher order perturbations in the field of the dilute object (proton), we derive the complete first saturation correction to the single inclusive semi-hard gluon production in high energy proton-nucleus collisions by applying the Lehmann-Symanzik-Zimmermann reduction formula. We thus finalize the program started by Balitsky (see Ref.~\cite{Balitsky:2004rr}) and independently by Chirilli, Kovchegov and Wertepny (see Ref.~\cite{Chirilli:2015tea}) albeit using a very different approach to carry out our calculati…
A parton picture of inclusive quasi-elastic electron-nucleus scattering, where individual nucleons are treated as (non point-like) partons of the nucleus, is presented. All the necessary target-mass corrections to asymptotic scaling are evaluated and a new scaling variable is obtained. Recent inclusive data from Jefferson Lab are analyzed and shown to scale in terms of the new variable. The new approach allows to extract in a model-independent way the nucleon light-cone momentum distribution in the nucleus.
We present a complete comparison of semi-inclusive $ν_μ$-$^{12}$C cross-section measurements by T2K and MINER$ν$A collaborations with the predictions from the SuSAv2-MEC model implemented in the neutrino-nucleus event generator GENIE and an unfactorized approach based on the relativistic distorted wave impulse approximation (RDWIA). Results, that include cross sections as function of the final muon and proton kinematics and correlations between both, show that the agreement with data obtained by the RDWIA approach, that accounts for final-state interactions, matches or improves GENIE-SuSAv2 pr…
We compare the results of the relativistic Green's function model with the experimental data of the charged-current inclusive differential neutrino-nucleus cross sections published by the T2K Collaboration. The model, which is able to describe both MINER$ν$A and MiniBooNE charged-current quasielastic scattering data, underpredicts the inclusive T2K cross sections.
We present a full kinematic analysis of neutrino-nucleus charged current quasielastic interactions based on the Local Fermi Gas model and the Random PhaseApproximation. The model was implemented in the NEUT Monte Carlo framework, which allows us to investigate potentially measurable observables, including hadron distributions. We compare the predictions simultaneously to the most recent T2K and MINERvA charged current (CC) inclusive, CC0$π$ and transverse kinematic-imbalance variable results. We pursuit a microscopic interpretation of the relevant reaction mechanisms, with the aim of achieving…
We discuss the saturation of the parton density in heavy ion collisions at RHIC energiesusing a Pomeron approach. Our predictions for the particle density in ion-ion collisions at RHIC energies can be utilized as the background for the observation of possible quark-gluon plasma production.
We study the quasi--elastic contribution to the inclusive $(ν_l,ν_l N)$, $(ν_l,l^- N)$, $({\bar ν}_l,{\bar ν}_l N)$ and $({\bar ν}_l,l^+ N)$ reactions in nuclei using a Monte Carlo simulation method to account for the rescattering of the outgoing nucleon. As input, we take the reaction probability from the microscopical many body framework developed in Phys. Rev. {\bf C70} (2004) 055503 for charged-current induced reactions, while for neutral currents we use results from a natural extension of the model described in that reference. The nucleon emission process studied here is a clear signal fo…
The Quasi-Elastic (QE) contribution of the nuclear inclusive electron scattering model developed in Nucl. Phys. A627 (1997) 543 is extended to the study of electroweak Charged Current (CC) induced nuclear reactions, at intermediate energies of interest for future neutrino oscillation experiments. The model accounts for, among other nuclear effects, long range nuclear (RPA) correlations, Final State Interaction (FSI) and Coulomb corrections. Predictions for the inclusive muon capture in $^{12}$C and the reaction $^{12}$C $(ν_μ,μ^-)X$ near threshold are also given. RPA correlations are shown to …
Inclusive cross-sections for gluon jet production are studied numerically in the perturbative QCD pomeron model for central collisions of identical nuclei at high energies. Two forms for the inclusive cross-sections, with and without emission from the triple pomeron vertex, are compared. The difference was found to reduce to a numerical factor 0.8$÷$ 09 for momenta $k$ below the saturation momentum $Q_s$. Above $Q_s$ no difference was found at all. The gluon spectrum was found to be $\sim A$ for $k<Q_s$ and $\sim A^{1.1}$ for $k>Q_s$. At large $k$ the spectrum falls as $1/k^{2.7÷3.3}$ flatteni…
It is shown that in semi-inclusive deep inelastic scattering (DIS) of electrons off a complex nucleus A, the detection, in coincidence with the scattered electron, of a nucleus (A-1) in the ground state, as well as of a nucleon and a nucleus (A-2), also in the ground state, may provide unique information on several long standing problems, such as : i) the nature and the relevance of the final state interaction in DIS; ii) validity of the spectator mechanism in DIS; iii) the medium induced modifications of the nucleon structure function; iv) the origin of the EMC effect.
Using the recently found hA amplitude, single and double inclusive jet production rates on the nucleus are studied in the perturbative QCD with $N_c\to\infty$. Jet multiplicities are found to grow with $A$ and energy as $A^{2/9}s^Δ$ where $Δ$ is the BFKL intercept. Long range correlations are found to behave as $A^{4/9}s^{2Δ}$ and change from negative to positive at a certain high energy.
We reconsider the perturbative next-to-leading calculation of the single inclusive hadron production in the framework of the hybrid formalism, applied to hadron production in proton-nucleus collisions. Our analysis, performed in the wave function approach, differs from the previous works in three points. First, we are careful to specify unambiguously the rapidity interval that has to be included in the evolution of the leading-order eikonal scattering amplitude. This is important, since varying this interval by a number of order unity changes the next-to-leading order correction that the calcu…
We analize semi-inclusive electron-nucleus processes e+A->e'+h+X at moderate Q**2 and energy transfer nu. Our results show that nucleons bound in the nuclear medium are distributed according to a function f_A that reduces to the standard light-cone distribution in the Bjorken limit and exhibits a sizeable Q**2-dependence at lower Q**2, particular Q**2 is order of nu**2.
We show that the quasielastic (QE) response calculated with the SuSAv2 (superscaling approach) model, that relies on the scaling phenomenon observed in the analysis of (e,e') data and on the relativistic mean-field theory, is very similar to that from a relativistic distorted wave impulse approximation model when only the real part of the optical potentials is employed. The coincidence between the results from these two completely independent approaches, which satisfactorily agree with the inclusive data, reinforces the reliability of the quasielastic predictions stemming from both models and …
We compute the differential cross-section for inclusive prompt photon production in deeply inelastic scattering (DIS) of electrons on nuclei at small $x$ in the framework of the Color Glass Condensate (CGC) effective theory. The leading order (LO) computation in this framework resums leading logarithms in $x$ as well as power corrections to all orders in $Q_{s,A}^2/Q^2$, where $Q_{s,A}(x)$ is the nuclear saturation scale. This LO result is proportional to universal dipole and quadrupole Wilson line correlators in the nucleus. In the soft photon limit, the Low-Burnett-Kroll theorem allows us to…
We compute the differential cross-section for inclusive prompt photon$+$quark production in deeply inelastic scattering of electrons off nuclei at small $x$ ($e+A$ DIS) in the framework of the Color Glass Condensate effective field theory. The result is expressed as a convolution of the leading order (in the strong coupling $α_{\mathrm{s}}$) impact factor for the process and universal dipole matrix elements, in the limit of hard photon transverse momentum relative to the nuclear saturation scale $Q_{s,A}(x)$. We perform a numerical study of this process for the kinematics of the Electron-Ion C…
In the perturbative QCD approach single and double inclusive cross-sections for gluon production off the nucleus are studied from the relevant reggeized gluon diagrams. Various terms corresponding to emission of gluons from the triple Pomeron vertex are found. Among them the term derived by Kovchegov and Tuchin emerges as a result of transition from the diffractive to effective high-energy vertex. However it does not exhaust all the vertex contributions to the inclusive cross-section. In the double inclusive cross-section a contribution violating naive AGK rules is found, in which one gluon is…
We analyze the experimental data on the inclusive double differential cross section by neutrinos charged current, measured by T2K, with the same model which was successful for the MiniBooNE quasielastic cross sections. As in our previous analysis the multinucleon component is needed in order to reproduce the data. For the total cross section our evaluation is smaller than the SciBooNE data above 1 GeV. This indicates the opening of a new channel not included in our evaluation, presumably the two pion emission channel. We also check that our description holds for the exclusive single pion produ…
We compute single inclusive hadron production in proton-proton and proton-nucleus collisions consistently within the CGC framework. The parameters in the calculations are obtained from electron-proton DIS and standard nuclear geometry. We obtain a good description of the DIS data without an anomalous dimension in the initial condition of the BK evolution and get a good agreement with the available single inclusive proton-proton and proton-nucleus data.
We study single inclusive hadron production in proton-proton and proton-nucleus collisions in the CGC framework. The parameters in the calculation are obtained by fitting electron-proton deep inelastic scattering data. The obtained dipole-proton amplitude is generalized to dipole-nucleus scattering without any additional nuclear parameters other than the Woods-Saxon distribution. We show that it is possible to use an initial condition without an anomalous dimension and still obtain a good description of the HERA inclusive cross section and LHC single particle production measurements. We argue …
In this article, we present the charged and neutral current coherent pion production in the neutrino-nucleus interaction in the resonance region using the formalism based on the partially conserved axial current (PCAC) theorem which relates the neutrino-nucleus cross section to the pion-nucleus elastic cross section. The pion nucleus elastic cross section is calculated using the Glauber model approach. We calculate the integrated cross sections for neutrino-carbon, neutrino-iron and neutrino-oxygen scattering. The results of integrated cross-section calculations are compared with the measured …
Single inclusive particle production at next-to-leading order in proton-nucleus collisions at forward rapidities: hybrid approach meets TMD factorization
We present results on rapidity and transverse momentum distributions of inclusive charm quark production in hadronic and heavy-ion collisions at RHIC and LHC energies, including the next-to-leading order, $O(α_s^3)$, radiative corrections and the nuclear shadowing effect. We determine the hadronic and the {\it effective} (in-medium) K-factor for the differential and total inclusive charm cross sections. We find the fraction of central and inelastic events that contain at least one charm quark pair at LHC energies and obtain the effective $A$-dependence of the inclusive charm production in prot…
Hadron production in lepton-nucleus deep inelastic scattering is studied in a model including quark energy loss and nuclear absorption. The leading-order computations for hadron multiplicity ratios are presented and compared with the selected HERMES experimental data with the quark hadronization occurring inside the nucleus by means of the hadron formation time. It is shown that with increase of the energy fraction carried by the hadron, the nuclear suppression on hadron multiplicity ratio from nuclear absorption gets bigger. It is found that when hadronization occurs inside the nucleus, the n…
Hadron production in lepton-nucleus deep inelastic scattering is studied in a quark energy loss model. The leading-order computations for hadron multiplicity ratios are presented and compared with the selected HERMES pions production data with the quark hadronization occurring outside the nucleus by means of the hadron formation time. It is found that the obtained energy loss per unit length is $0.440 \pm 0.013$ GeV/fm for an outgoing quark by the global fit. It is confirmed that the atomic mass number dependence of hadron attenuation is theoretically and experimentally in good agreement with …
The leading order single inclusive soft gluon production in high energy proton-nucleus (pA) collisions has been studied by various approaches for more than two decades. The first correction due to the gluon saturation in proton was analytically attempted recently through a diagrammatic approach in which only partial results were obtained. An important feature of the first saturation correction is that it includes both initial state and final state interactions. In this paper, we present the complete result derived from the Color Glass Condensate framework. Our approach is to analytically solve…
High-energy antinucleus-nucleus collisions are studied in the extended multi-chain model. The event probability of inclusive process is calculated by means of the operator matrix in the moment space. Analytic forms for single-particle distribution of inclusive process are derived.
The semi-inclusive properties of the system of neutral and charged particles with net charge equal to zero are considered in the grand canonical, canonical and micro-canonical ensembles as well as in micro-canonical ensemble with scaling volume fluctuations. Distributions of neutral particle multiplicity and charged particle momentum are calculated as a function of the number of charged particles. Different statistical ensembles lead to qualitatively different dependencies. They are being compared with the corresponding experimental data on multi-hadron production in $p+p$ interactions at high…
We review Quasielastic (QE) inclusive and semi--inclusive neutrino/antineutrino Charged Current (CC) and Neutral Current (NC) induced nuclear reactions at intermediate energies. We pay special attention to nuclear corrections besides Pauli blocking: Long and Short range nuclear correlations (RPA and SRC) and particle and hole Spectral Functions (SF). We also critically review the use of the Plane and Distorted Wave Impulse approximations (PWIA and DWIA) to describe inclusive one nucleon knockout reactions off nuclei. In this context, we present results from a Monte Carlo cascade method to acco…
We estimate the theoretical uncertainties of the model developed in Phys. Rev. C70 055503 for inclusive quasielastic charged-current neutrino-nucleus reactions at intermediate energies. Besides we quantify the deviations of the predictions of this many body framework from those obtained within a simple Fermi gas model. An special attention has been paid to the ratio σ(μ)/σ(e) of interest for experiments on atmospheric neutrinos. We show that uncertainties affecting this ratio are likely smaller than 5%
Similarly to the previously studied case of inclusive $t\bar t$ production we consider the inclusive $t\bar b$ production in $e^+e^-$, gluon~gluon and photon~photon collisions. We show how it is sensitive to new physics, connected to the charged Goldstone sector and possibly generated by Higgs and/or top quark compositeness.
We have carried out a calculation of the inclusive electron scattering cross section off oxygen in the kinematical region corresponding to beam energies between 700 and 1200 MeV, where quasielastic scattering and single pion production are the dominant reaction mechanisms. The formalism developed and successfully applied to describe quasielastic scattering has been extended to include both delta production and non-resonant pion production. The results are in fairly good agreement with experimental data over the whole range of energy transfer, including the dip region between the quasielastic p…
We evaluate the quasielastic and multinucleon contributions to the antineutrino nucleus scattering cross section and compare our results with the recent MiniBooNE data. We use a local Fermi gas model that includes RPA correlations and gets the multinucleon part from a systematic many body expansion of the $W$ boson selfenergy in the nuclear medium. The same model had been quite successful for the neutrino cross section and contains no new parameters. We have also analysed the relevance of 2p2h events for the antineutrino energy reconstruction.
We explore the quark mass effects on inclusive hadron production in proton-nucleus collisions at high energies. We consider two processes. First, we compute the single inclusive cross-section for production of hadrons with open heavy flavour in the proton forward direction at leading order. Next, in the same kinematics, we calculate the heavy-quark contribution to single inclusive production of light or unidentified hadrons at next-to-leading-order. For both studies we exploit the hybrid formalism, that is the collinear factorisation on the proton side while high-density and high-energy effect…
We calculate the centrality dependence of the midrapidity nuclear modification for inclusive prompt photon production in d+Au and Au+Au collisions at RHIC and in p+Pb and Pb+Pb collisions at the LHC. Our results, using the recent spatially dependent nuclear PDF set EPS09s, are consistent with the existing high-pT data from the PHENIX and CMS collaborations. The good agreement even in the case of nucleus+nucleus collisions suggests that the high-pT direct photon production is not significantly altered by the strongly interacting medium produced in such collisions. We find the centrality depende…
The inclusive double Pomeron exchange cross section for heavy quark pair production is calculated for nucleus-nucleus collisions at the LHC. The present estimate is based on hard diffractive factorization, corrected by absorptive corrections and nuclear effects. The theoretical uncertainties for nuclear collisions are investigated and a comparison to other approaches is presented. The production channels producing a similar final state configuration are discussed as well.
We extend previous results (arXiv:0804.2630 [hep-ph]) on factorization in high-energy nucleus-nucleus collisions by computing the inclusive multigluon spectrum to next-to-leading order. The factorization formula is strictly valid for multigluon emission in a slice of rapidity of width ΔY< 1/α_s. Our results show that often neglected disconnected graphs dominate the inclusive multigluon spectrum and are essential to prove factorization for this quantity. These results provide a dynamical framework for the Glasma flux tube picture of the striking "ridge"-like correlation seen in heavy ion collis…
We derive a high energy factorization theorem for inclusive gluon production in A+A collisions. Our factorized formula resums i) all order leading logarithms (g^2 \ln(1/x_{1,2}))^n of the incoming partons momentum fractions, and ii) all contributions (g ρ_{1,2})^n that are enhanced when the color charge densities in the two nuclei are of order of the inverse coupling-- ρ_{1,2}\sim g^{-1}. The resummed inclusive gluon spectrum can be expressed as a convolution of gauge invariant distributions W[ρ_{1,2}] from each of the nuclei with the leading order gluon number operator. These distributions ar…
The effects of multiple interactions in colliding particles (e.g. in nucleus-nucleus collisions) are modeled using the light-cone dipole approach. Guided by the abelian analogue of multi-photon interactions in the production of a pair of charged particles, we relate the inclusive cross section of quark pair production with the cross sections of interaction of a QCD dipole with either the beam or the target.
We discuss the observed disagreement between the Q^2 distributions of neutrino-nucleus quasielastic events, measured by a number of recent experiments, and the predictions of Monte Carlo simulations based on the relativistic Fermi gas model. The results of our analysis suggest that these discrepancies are likely to be ascribable to both the breakdown of the impulse approximation and the limitations of the Fermi gas description. Several issues related to the extraction of the Q^2 distributions from the experimental data are also discussed, and new kinematical variables, which would allow for an…
We compute the influence of Coulomb effects on the charged kaon distribution at low momentum in high energy nucleus-nucleus collisions. This is accomplished by solving the Vlasov equation for the kaons in the presence of an expanding, highly charged, fireball.
I review the description of the electroweak nuclear response at large momentum transfer within nonrelativistic many-body theory. Special consideration is given to the effects of final state interactions, which are known to be large in both inclusive and semi-inclusive processes. The results of theoretical calculations of electron-nucleus scattering observables are compared to the data, and the generalization to charged current neutrino-nucleus interactions is discussed.
The results of two relativistic models with different descriptions of the final-state interactions are compared with the MiniBooNE data of charged-current quasielastic cross sections. The relativistic mean field model uses the same potential for the bound and ejected nucleon wave functions. In the relativistic Green's function (RGF) model the final-state interactions are described in the inclusive scattering consistently with the exclusive scattering using the same complex optical potential. The RGF results describe the experimental data for total cross-sections without the need to modify the …
The quasielastic scattering of muon neutrinos on oxygen 16 is studied for neutrino energies between 200 MeV and 1 GeV using a relativistic shell model. Final state interactions are included within the distorted wave impulse approximation, by means of a relativistic optical potential, with and without imaginary part, and of a relativistic mean field potential. For comparison with experimental data the inclusive charged--current quasielastic cross section for $ν_μ$--$^{12}C$ scattering in the kinematical conditions of the LSND experiment at Los Alamos is also presented and briefly discussed.
The distorted spin-dependent spectral function of a nucleon inside an A=3 nucleus is introduced as a novel tool for investigating the polarized electron scattering off polarized $^3$He in semi-inclusive DIS regime (SiDIS), going beyond the standard plane wave impulse approximation. This distribution function is applied to the study of the spectator SiDIS, $\vec{^3{\rm He}}(\vec e, e' ~{^2}{\rm H})X$, in order to properly take into account the final state interaction between the hadronizing quark and the detected deuteron, with the final goal of a more reliable extraction of the polarized parto…
In terms of multiple scattering picture, we calculate the double scattering effect in the transverse momentum distribution of $J/ψ$ photoproduction. Applying the generalized factorization theorem, we find that the contributions from double scattering can be expressed in terms of twist-4 nuclear parton correlation functions, which is the same as that used to explain the nuclear dependence in di-jet momentum imbalance and in direct photon production. Using the known information on the twist-4 parton correlation functions, we estimate that the double scattering contributes a small suppression in …
We have studied a method to extract neutrino flux from the data of neutrino-nucleus reaction by using maximum entropy method. We demonstrate a promising example to extract neutrino flux from the inclusive cross section of muon production without selecting a particular reaction process such as quasi-elastic nucleon knockout.
In the framework of perturbative QCD, double inclusive cross sections for high $p_t$ parton production in nucleus-nucleus collisions are computed with multiple rescattering taken into account. The induced long-range correlations between numbers of jets at forward and backward rapidities are found to reach $10÷20$% for light nuclei at $\sqrt{s}=200$ GeV/c and to be suppressed for heavy nuclei and LHC energies.
In the Color Glass Condensate formalism, charged hadron p_{T} distributions in p+p collisions are studied by considering an energy-dependent broadening of nucleon's density distribution. Then, in the Glasma flux tube picture, the n-particle multiplicity distributions at different pseudo-rapidity ranges are investigated. Both of the theoretical results show good agreement with the recent experimental data from ALICE and CMS at \sqrt{s}=0.9, 2.36, 7 TeV. The predictive results for p_{T} and multiplicity distributions in p+p and p+Pb collisions at the Large Hadron Collider are also given in this …
The semi-inclusive deep inelastic scattering of electrons off a nucleus A with detection of a slow nucleus (A-1) in the ground or low excitation states, i.e. the process A(e,e'(A-1))X, can provide useful information on the origin of the EMC effect and the mechanisms of hadronization. The theoretical description of the process is reviewed and the results of several calculations on few-body systems and complex nuclei are presented.
The new contributions to the charmless B decay $B \to X_{s}η^{\prime}$ from the unit-charged technipions $P^{\pm}$ and $P^{\pm}_{8}$ are estimated. The technipions can provide a large enhancement to the inclusive branching ratio: $Br(B \to X_{s}η^{\prime}) \sim 7\times 10^{-4}$ for $m_{p1}=100GeV$ and $m_{p8}=250 \sim 350 GeV$ when the effect of QCD gluon anomaly is also taken into account. The new physics effect is essential to interpret the CLEO data.
