To achieve appropriate interaction rates in recent neutrino oscillation studies, high atomic number nuclear targets were utilized. Because of the nuclear effects in the experimental observable, the utilization of these complicated targets produced systematic uncertainties that needed to be assessed accurately to constrain the discovery. We made an effort to calculate the nuclear effects in the Ar and H targets, which are intended to be employed at the DUNE distant and near detectors, respectively, through our simulation effort. The DUNE flux is peaking around 2.5 GeV and CCRES is the dominant process at this energy. So, this work will be focused only on the CCQE and CCRES interactions and the simulations will be done using two different neutrino event generators. We reported the ratio of the oscillation probability (P(Ar)/P(H) as a function of reconstructed neutrino energy for CCRES channels to quantify the systematic errors in the observables.
The reaction mechanisms for neutrino interactions with an $^{40}Ar$ nucleus with the LBNF flux are calculated with the Giessen-Boltzmann-Uehling-Uhlenbeck (GiBUU) transport-theoretical implementation of these interactions. Quasielastic scattering, many-body effects, pion production and absorption and Deep Inelastic Scattering are discussed; they all play a role at the LBNF energies and are experimentally entangled with each other. Quasielastic scattering makes up for only about 1/3 of the total cross section whereas pion production channels make up about 2/3 of the total. This underlines the n…
The final state interactions (FSI) model, in which soft rescattering of low mass intermediate states dominate, is suggested. It explains why the strong interaction phases are large in the $B_d\toππ$ channel and are considerably smaller in the $B_d\toρρ$ one.
The final state interaction (FSI) contribution to charged $D$ decay into $Kππ$ is computed within a light-front framework, considering $S$-wave $Kπ$ interactions in $1/2$ and $3/2$ isospin states. The convergence of the rescattering series is checked computing terms up to the third perturbative order. The role of the resonances above $K^*_0(1430)$, and the contribution of the $Kπ$ $3/2$ isospin channel to charged three-body $D$ decays, are studied against the available phase-shift analysis.
A method parametrizing all inelastic final state interactions (FSI) in $B\to PP$ decays is presented ($P$ - pseudoscalar meson). The method explicitly shows how rescattering leads to the replacement of the short-distance amplitudes with the effective quark diagram amplitudes, and how it affects the extraction of the unitarity triangle angle $γ$ from the data. It is furthermore pointed out that the size of FSI effects cannot be determined from $B^0_d \to K^+ K^-$ decays in a satisfactory way. The case of SU(3)-violating FSI is also discussed. When fits to the branching ratios of all $B \to PP$ …
The final state interactions (FSI) model in which soft rescattering of low mass intermediate states dominates is suggested. It explains why the strong interaction phases are large in the $B_d\toππ$ channel and are considerably smaller in the $B_d\toρρ$ one. Direct CP asymmetries of $B_d\toππ$ decays which are determined by FSI phases are considered as well.
It is believed that the production rate of $D^0\to K^0\bar K^0$ is almost solely determined by final state interactions (FSI) and hence provides an ideal place to test FSI models. Here we examine model calculations of the contributions from s-channel resonance $f_J(1710)$ and t-channel exchange to the FSI effects in $D^0\to K^0\bar K^0$. The contribution from s-channel $f_0(1710)$ is sma$ For the t-channel FSI evaluation, we employ the one-particle-exchange (OPE) model and Regge model respecti$ The results from two methods are roughly consistent with each other and can reproduce the large rate…
Understanding the pion generation and the consequences of final-state interactions (FSI) are critical for the data processing in all neutrino experiments. The energy utilized in modern neutrino research of the resonance (RES) generation processes contributes significantly to the pion production. If a pion is absorbed in the nuclear matter after its production, the event may become unrecognizable from a quasielastic (QE) scattering process and act as a background. For oscillation experiments, estimating this background is critical, and it necessitates solid theoretical models for both pion gene…
By using very general and well established features of soft strong interactions we show, contrary to conventional expectations, that (i) soft final state interactions (FSI) do not disappear for large $m_B$, (ii) inelastic rescattering is expected to be the main source of soft FSI phases, and (iii) flavor off-diagonal FSI are suppressed by a power of $m_B$, but are quite likely to be significant at $m_B\simeq 5$~GeV. We briefly discuss the influence of these interactions on tests of CP-violation and on theoretical calculations of weak decays.
We are presenting here the new formulae for Bose-Einstein correlations (BEC) which contain effects of final state interactions (FSI) of both strong (in $s$-wave) and electromagnetic origin. We demonstrate the importance of FSI in BEC by analysing data for $e^+e^-$ annihilation and for heavy collisions. The inclusion of FSI results in the practical elimination (at least in $e^+e^-$ data) of the so called degree of coherence parameter $λ$ (which becomes equal unity) and the long range parameter $γ$ (which is now equal zero).
For hadronic two-body decays of charmed mesons involving $η$ or $η'$, resonance-induced final-state interactions (FSI) that mimic the W-exchange or the W-annihilation topology can play an essential role. In particular, the decays $D^0\to\bar K^0η'$ and $D^+\toπ^+η$, which are largely suppressed in the absence of FSI, are enhanced dramatically by resonant FSI. It is stressed that the effect of resonant FSI is negligible for $ρ^+(η,η')$ final states because of the mismatch of the G parity of $ρ^+(η,η')$ and the J=0, I=1 meson resonance. We argue that a possible gluon-mediated process in which tw…
We analyzed the process of $B_s\rightarrow ρρ$ decay in QCD factorization (QCDF) and final state interaction (FSI) effects. In QCDF for this decay we have only the annihilation graph and we expected small Branching ratio. Then we considered FSI effect as a sizable correction where the intermediate states are $π^0π^0$, $π^+π^-$, $K^0\bar{K^0}$ and $K^+K^-$ mesons. To consider the amplitudes of these intermediate states, QCDF approach was used. The experimental branching ratio of $B_s\rightarrow ρρ$ is less than $3.20\times 10^{-4}$ and our result is $1.08 \times 10^{-9}$ and $3.29 \times10^{-4}…
I discuss the role of strong final state interactions (FSI) in K \to 2πdecays. In this case strong FSI effects can be resummed [1,2] by solving the Omnès problem for K\to 2πamplitudes. Implications for the CP conserving Delta I=1/2 ratio and the direct CP violation parameter eps'/eps are also discussed.
Evidence of physics beyond the Standard Model (SM) of particle physics might be revealed through CP violation. Experimental results from BaBar, Belle, and most recently from LHCb are very interesting in this respect. It is important to calculate various CP violation parameters within the SM. In this Letter, the final state interaction (FSI) phases with the CKM matrix are calculated using the recent experimental results from LHCb on CP violation in B0 and Bs0 meson decays. To obtain the allowed regions of the FSI phases, a simplified form of the Jarlskog determinant of the CKM matrix is used an…
The incoherent pion photoproduction reaction gd-->pi-pp is considered theoretically in a wide energy region Eth =< Eg =< 2700 MeV. The model applied contains the impulse approximation as well as the NN- and piN-FSI amplitudes. The aim of the paper is to study a reliable way for getting the information on elementary gn-->pi-p reaction cross section beyond the impulse approximation for gd-->pi-pp. For the elementary gN-->piN, NN-->NN, and piN-->piN amplitudes, the results of the GW DAC are used. There are no additional theoretical constraints. The calculated cross section dSigma/dOmega(gd->pi-pp…
The study of pion production and the effects of final state interactions (FSI) are important for data analysis in all neutrino experiments. For energies at which current neutrino experiments are being operated, a significant contribution to pion production is made by resonance production process. After its production, if a pion is absorbed in the nuclear matter, the event may become indistinguishable from quasi-elastic scattering process and acts as a background. The estimation of this background is very essential for oscillation experiments and requires good theoretical models for both pion p…
We study the final-state interaction (FSI) effects in charmless B_{u,d,s} to PP decays. We consider a FSI approach with both short- and long-distance contributions, where the former are from in-elastic channels and are contained in factorization amplitudes, while the latter are from the residual rescattering among PP states. Flavor SU(3) symmetry is used to constrain the residual rescattering S-matrix. We fit to all available data on the CP-averaged decay rates and CP asymmetries, and make predictions on unmeasured ones. Our main results are as follows: (i) Results are in agreement with data i…
In this paper the decay of $B^+_c$ meson, consisting of two b and c heavy quarks, into the $D^0$ and $K^+$ mesons is studied. Given that the experimental branching ratio for this decay is within the range of $3.72\times 10^{-5}$ to $11.16\times10^{-5}$ and in our estimating the theoretical result by using the QCD factorization approaches is $10^2$ times less than experimental one (we have obtained $1.41\times10^{-7}$), it is decided to calculate the theoretical branching ratio by applying the final state interaction (FSI) through the T and cross section channels. In this process, before the $B…
A model based on the relativistic impulse approximation for quasielastic lepton-nucleus scattering is presented. The effects of the final-state interactions (FSI) between the emitted nucleon and the residual nucleus are described by the relativistic Green's function model where FSI are treated consistently with the exclusive scattering and using the same complex optical potential. The results of the model are compared with the results of different descriptions of FSI and with available data for neutrino-nucleus scattering.
Recently we have conjectured that (in-)elastic collisions of (pre-)hadronic high momentum states with the bulk of hadrons in the late fireball might substantially account for the attenuation of the high transverse momentum hadrons at RHIC. The potential hadronic attenuation has therefore to be addressed in further detail before definite conclusions on possible QCD effects in a deconfined QGP phase can be drawn with respect to the materializing jets. From our transport studies we find that the interactions of fully formed hadrons are practically negligible in central Au+Au collisions at \sqrt s…
The chromopolarizability of a quarknonium describes the quarknonium's interaction with soft gluonic fields and can be measured in the heavy quarkonium decays. Within the framework of dispersion theory which consider the $ππ$ final state interaction (FSI) model-independently, we analyze the transition $ψ^\prime\to J/ψπ^+π^-$ and obtain the chromopolarizability $α_{ψ^\prime ψ}$ and the parameter $κ$. It is found that the $ππ$ FSI plays an important role in extracting the chromopolarizability from the experimental data. The obtained chromopolarizability with the FSI is reduced to about 1/2 of tha…
We investigate whether the final state interaction (FSI) effect plays a significant role in the large hidden charm decay width of X(3872) and Y(3940) using a model. Our numerical result suggests (1) the FSI contribution to $X(3872)\to J/ψρ$ is tiny; (2) $Γ[ Y(3940)\to D\bar{D}^{*}+\text{h.c.}\to J/ψω]$ from FSI is around several keV, far less than Belle's experimental value 7 MeV.
Strong final state interaction (FSI) effects can play a central role in the Standard Model prediction of weak $K\to 2π$ matrix elements. Here, I discuss how FSI's affect the direct CP violation parameter $\vepp / \vep$ by solving the Omnès problem for the necessary $K\to 2π$ amplitudes. The main results of this analysis have been reported in a previous paper [1] and are further discussed in Refs. [2,3]. The resulting Standard Model prediction ${Re} (\vepp / \vep) = (15\pm 5)\times 10^{-4}$ is in good agreement with the present experimental world average.
We discuss all contributions from Zweig-rule-satisfying SU(3)-breaking final state interactions (FSIs)in the B -> PP decays (neglecting charmed intermediate states), where PP=pi pi, pi K, KK, pi eta (eta'), and K eta (eta'). First, effects of SU(3) breaking in rescattering through Pomeron exchange are studied. Then, after making a plausible assumption concerning the pattern of SU(3) breaking in non-Pomeron FSIs, we give general formulas for how the latter modify short-distance (SD) amplitudes. In the SU(3) limit, these formulas depend on three effective parameters characterizing the strength o…
Recently DELPHI Collaboration reported new data on Bose-Einstein correlations (BEC) measured in e+e- -> W^+W^- events. Apparently no enhancement has been observed. We have analyzed these data including final state interactions (FSI) of both Coulomb and strong (s-wave) origin and found that there is enhancement in BEC but it is overshadowed by the FSI which are extremely important for those events. We have found the following values for the size of the interaction range beta and the degree of coherence lambda: beta=0.87 +/- 0.31fm and lambda=1.19 +/- 0.48, respectively.
With the diquark structure of Lambda_c, we investigate the branching ratios of Lambda_c -> n pi^+ and p pi^0. The results show that without considering the final state interaction (FSI), the branching ration of Lambda_c -> p pi^+ is only of order 10^{-6} whereas taking into account the FSI effects, this ratio could reach 10^{-4} and is at the same order as Lambda_c -> n pi^0. Concrete values depend on phenomenological parameters adopted in the calculations. These branching ratios can be measured in the experiments to come.
The photoproduction of K0 on the deuteron has been investigated with the inclusion of YN and KN final-state interaction (FSI), as well as the pion-mediated process gamma d --> pi NN --> KYN. The YN rescattering effects for the inclusive cross section are found to be large in the threshold regions. Polarization observables show sizable FSI effects at larger kaon and hyperon angles. It is shown that the extraction of the elementary gamma N --> KY amplitude is possible in the quasi-free scattering region where FSI effects are negligible. Furthermore, the cross sections in this region are large, i…
The current and near-future neutrino oscillation experiments require significantly improved neutrino-nucleus reaction models. Neutrino-nucleon pion production data play a crucial role to validate corresponding elementary amplitudes that go into such neutrino-nucleus models. Thus the currently available data extracted from charged-current neutrino-deuteron reaction data ($ν_μd\to μ^-πNN$) must be corrected for nuclear effects such as the Fermi motion and final state interactions (FSI). We study $ν_μd\to μ^-πNN$ with a theoretical model including the impulse mechanism supplemented by FSI from $N…
We consider electron-deuteron deep-inelastic scattering (DIS) with detection of a proton in the nuclear fragmentation region ("spectator tagging") as a method for extracting the free neutron structure functions and studying their nuclear modifications. Such measurements could be performed at a future Electron-Ion Collider (EIC) with suitable forward detectors. The measured proton recoil momentum (~< 100 MeV in the deuteron rest frame) specifies the deuteron configuration during the high-energy process and permits a controlled theoretical treatment of nuclear effects. Nuclear and nucleonic stru…
The chromo-polarizability of a quarkonium state is a measure of the amplitude of the $E1$-$E1$ chromo-electric interaction of the quarkonium with soft gluon fields and can be measured in the heavy quarkonium decays. Based on the chiral unitary approach, formulas with modification caused by the $S$ wave $ππ$ final state interaction (FSI) for measuring the chromo-polarizabilities are given. It is shown that the effect of the $S$ wave $ππ$ FSI is very important in extracting chromo-polarizabilities from the experimental data. The resultant values with the FSI are reduced to about 1/3 of those det…
The description of final-state interactions (FSI) in the large phase space probed in neutrino experiments poses a great challenge. In neutrino experiments, which operate under semi-inclusive conditions, cascade models are commonly used for this task, while under exclusive conditions FSI can be treated with relativistic optical potentials (ROP). We formulate conditions under which the ROP approach and cascade model can be directly compared. We feed the NEUT cascade with events from a relativistic distorted-wave impulse approximation calculation that uses the real part of an optical potential. C…
Deep-inelastic scattering (DIS) from a tensor polarized deuteron is sensitive to possible non-nucleonic components of the deuteron wave function. To accurately estimate the size of the nucleonic contribution, final-state interactions (FSIs) need to be accounted for in calculations. We outline a model that, based on the diffractive nature of the effective hadron-nucleon interaction, uses the generalized eikonal approximation to model the FSIs in the resonance region, taking into account the proton-neutron component of the deuteron. The calculation uses a factorized model with a basis of three r…
In this letter we suggest that the obvious discrepancy between theoretical prediction on the $\mathrm{non}-D\bar D$ decays of $ψ(3770)$ and data is to be alleviated by taking final state interaction (FSI) into account. By assuming that $ψ(3770)$ overwhelmingly dissociates into $D\bar D$, then the final state interaction induces a secondary process, we calculate the branching ratios of $ψ(3770)\to D\bar D\to J/ψη, ρπ, ωη, K^*K$. Our results show that the branching ratio of $ψ(3770)\to \mathrm{non}-D\bar{D}$ can reach up to $\mathcal{B}_{\mathrm{non}-D\bar{D}}^{FSI}=(0.2\sim1.1)%$ while typical …
We explore the role of final-state interactions (FSI) in inclusive deep-inelastic scattering from the deuteron. Relating the inclusive cross section to the deuteron forward virtual Compton scattering amplitude, a general formula for the FSI contribution is derived in the generalized eikonal approximation, utilizing the diffractive nature of the effective hadron-nucleon interaction. The calculation uses a factorized model with a basis of three resonances with mass $W<2$ GeV and a continuum contribution for larger $W$ as the relevant set of effective hadron states entering the final-state intera…
Relativistic models developed within the framework of the impulse approximation for quasielastic (QE) electron scattering and successfully tested in comparison with electron-scattering data have been extended to neutrino-nucleus scattering. Different descriptions of final-state interactions (FSI) in the inclusive scattering are compared. In the relativistic Green's function (RGF) model FSI are described consistently with the exclusive scattering using a complex optical potential. In the relativistic mean field (RMF) model FSI are described by the same RMF potential which gives the bound states…
A systematic analysis of the near-threshold enhancement in the $\bar pp$ invariant mass spectrum seen in the decay reactions $J/ψ\to x \bar pp$ and $ψ(3686) \to x \bar pp$ $(x = γ,\, ω,\, ρ,\, π,\, η)$ is presented. The enhancement is assumed to be due to the $\bar NN$ final-state interaction (FSI) and the pertinent FSI effects are evaluated in an approach that is based on the distorted-wave Born approximation. For the $\bar NN$ interaction a recent potential derived within chiral effective field theory and fitted to results of a partial-wave analysis of $\bar pp$ scattering data is considered…
To testify the validity of the perturbative QCD (pQCD) and investigate its application range, one should look for a suitable process to do the job. $B\to J/ψD$ is a promising candidate. The linear momentum of the products is relatively small, so that there may exist a region where exchanged gluons are soft and the perturbative treatment may fail, so that the non-perturbative effect would be significant. We attribute such non-perturbative QCD effects into the long-distance final state interaction (FSI) which is estimated in this work. We find that the contribution from the FSI to the branching …
Data for pion photo-productions off the neutron ($γn\to πN$) have been primarily extracted from deuteron-target data ($γd\to πNN$) by applying kinematical cuts thereby isolating the quasi-free samples. We critically examine if the neutron-target data obtained through this conventional procedure can be contaminated by final state interactions (FSI) and/or the kinematical cuts. The analysis is conducted with a theoretical model for $γd\to πNN$ that takes account of the impulse mechanisms supplemented by the $NN$ and $πN$ rescattering mechanisms. We show that the FSI effects still visibly remain …
The effects of the final state interaction (FSI) in semi inclusive deep inelastic electron scattering processes $A(e,e'p)X$ off nuclei are investigated in details. Proton production is described within the spectator and the target fragmentation mechanisms whose relevance to the experimental study of the deep inelastic structure functions of bound nucleons and the non perturbative hadronization process is analyzed. Particular attention is paid to the deuteron target within kinematical conditions corresponding to the available and forthcoming experimental data at Jlab. We argue that there are ki…
The analysis of quasielastic neutrino and antineutrino-nucleus scattering cross sections requires relativistic theoretical descriptions also accounting for the role of final-state interactions (FSI). In the relativistic Green's function (RGF) model FSI are described by a complex optical potential where the imaginary part recovers the contribution of final-state channels that are not included in other models based on the impulse approximation. The RGF results are compared with the data recently published by the MiniBooNE and MINER$ν$A Collaborations. The model is in general able to give a good …
We examine the role of resonant coupled channel final state interactions (FSI), as well as weak annihilation and exchange contributions in explaining all the two body hadronic $D\rightarrow PP$ decay modes data. In the un-unitarized amplitudes we include modified Wilson coefficients with non-factorizable corrections as parameters. For the hadronic form factors, the z-series expansion method is used to get the $q^2$ dependence. The FSI effects are incorporated via a phenomenological approach with widths of resonances to various channels taken from observations where available, and others as add…
An examination is conducted on a commonly used procedure for extracting (un)polarized $γn\to π^-p$ and $γn\to π^0n$ observables from $d(γ,π^-)pp$ and $d(γ,π^0)pn$ data, using a model that consists of the impulse term and the final-state interaction (FSI) terms due to nucleon- and pion-exchange. Recent experimental and theoretical analyses used an extraction method that does not impose a cut on the final $πN$ invariant mass $W$. I demonstrate that the use of this method can result in the $γn\to πN$ observables that are seriously distorted by the nucleon Fermi motion, and that one can efficientl…
I overview our recent activity with the Argonne-Osaka dynamical coupled-channels (DCC) approach that provides a unified description of various electroweak meson productions on single nucleon and nucleus. First I discuss the DCC model of a single nucleon. The DCC model has been developed through a comprehensive analysis of $πN, γN\to πN, ηN, KΛ, KΣ$ reaction data. The model has been further extended to finite $Q^2$ region by analyzing pion electroproduction data, and to neutrino-induced reactions using the PCAC relation. Next I discuss applications of the DCC model to electroweak meson producti…
