Krzysztof Graczyk Homepage

Peer reviewed articles


Krzysztof M. Graczyk, Beata E. Kowal
Spin asymmetry in single pion production induced by weak interactions of neutrinos with polarized nucleons ,
Phys. Rev. D99, 053002 (2019).
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Abstract:

The single pion production (SPP) in the chargedcurrent neutrino (antineutrino) scattering off the polarized nucleon is discussed. The spin asymmetry is predicted within two approaches. The longitudinal and perpendicular, to the neutrino momentum, spin polarizations of the target nucleon are considered. It is shown, in several examples, that the spin asymmetry contains complementary to spin averaged cross section measurements information about the SPP dynamics. Indeed, the spin asymmetry is sensitive to the nonresonance background description of the SPP model. For the normal polarization of the target the spin asymmetry is given by the interference between the resonance and the nonresonance contributions.

Luis AlvarezRuso, Krzysztof M. Graczyk, Eduardo SaulSala,
Nucleon axial form factor from a Bayesian neuralnetwork analysis of neutrinoscattering data,
Phys. Rev. C99, 025204 (2019).
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Abstract:

The Bayesian approach for feedforward neural networks has been applied to the extraction of the nucleon
axial form factor from the neutrinodeuteronscattering data measured by the Argonne National Laboratory
bubblechamber experiment. This framework allows to perform a modelindependent determination of the axial
form factor from data. When the low 0.05 < Q2 < 0.10GeV2 data are included in the analysis, the resulting
axial radius disagrees with available determinations. Furthermore, a large sensitivity to the corrections from
the deuteron structure is obtained. In turn, when the lowQ2 region is not taken into account with or without
deuteron corrections, no significant deviations from previous determinations have been observed. A more
accurate determination of the nucleon axial form factor requires new precise measurements of neutrinoinduced
quasielastic scattering on hydrogen and deuterium.

Krzysztof M. Graczyk and B. E. Kowal,
Polarization transfer in weak pion production off the nucleon,
Phys. Rev. D97, 013001 (2018).
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Abstract:

Polarization transfer (PT) observables in the single pion production induced by the charged current
interaction of the neutrino with the nucleon are examined. The polarization components of the final
nucleon and the charged lepton are calculated within two models for the pion production.
The predictions are made for neutrino energy of the order of 1 GeV as well as for the T2K energy distribution.
It is demonstrated that the PT observables, the degree of polarization and the polarization components of outgoing fermions,
are sensitive to assumptions about the nonresonant background model.
In particular it is shown that the normal components of the polarization of the outgoing nucleon and the lepton
are determined by the interference between the resonant (RES) and nonresonant (NB) amplitudes.
Moreover, the sign of the normal component of the polarization of the charged lepton is fixed
by the relative sign between the RES and the NB amplitudes.

K. M. Graczyk and C. Juszczak,
Zemach moments of proton from Bayesian inference,
Phys. Rev. C91, 045205 (2015).
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Abstract:

The first and the third Zemach moments are obtained, $\langle r \rangle_{(2)}= 1.1108\pm 0.0021 $ fm and $\langle r^3\rangle_{(2)}=2.889 \pm 0.008$ fm$^3$,
from the Bayesian analysis of the elastic $ep$ scattering data.
The quantitative discussion of the dependence of the results
on the parametrization choice is presented and the corresponding systematic uncertainties are estimated  about 0.6\% and 1.6\% for the first and the third Zemach moments respectively.

K. M. Graczyk and C. Juszczak,
Applications of Neural Networks in Hadron Physics,
J.Phys. G: Nucl. Phys. 42 034019 (2015).
invited contribution to special issue entaitled "Enhancing the interaction between nuclear experiment and theory through information and statistics" (ISNET).
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Abstract:

The Bayesian approach for the feedforward neural networks is reviewed.
Its potential for usage in hadron physics is discussed.
As an example of the application the study of the the twophoton exchange effect is presented. We focus on the model comparison,
the estimation of the systematic uncertainties due to the choice of the model, and the overfitting.
As an illustration the predictions of the cross sections ratio $d \sigma(e^+ p\to e^+ p)/d \sigma(e^ p\to e^ p)$
are given together with the estimate of the uncertainty due to the parametrization choice.

Krzysztof M. Graczyk and C. Juszczak,
Proton Radius from Bayesian Inference,
Phys. Rev. C90, 054334 (2014).
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Abstract:

The methods of Bayesian statistics are used to extract the value of the proton radius
from the elastic $ep$ scattering data in a model independent way.
To achieve that goal a large number of parametrizations
(equivalent to neural network schemes) are considered and ranked by
their conditional probability $P(\mathrm{parametrization}\,\,\mathrm{data})$ instead of using the minimal error criterion.
As a result the most probable proton radii values ($r_E^p=0.899\pm 0.003$ fm, $r_M^p=0.879\pm 0.007$ fm) are obtained and systematic error due to freedom in the choice of parametrization is estimated.
Correcting the data for the two photon exchange effect leads to smaller difference between the extracted values of $r_E^p$ and $r_M^p$.
The results disagree with recent muonic atom measurements.

Krzysztof M. Graczyk, Jakub Zmuda, Jan T. Sobczyk,
Electroweak Form Factors of the Delta(1232) Resonance,
Phys. Rev. D90, 093001 (2014).
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Abstract:

Nucleon $\to \Delta(1232)$ transition electroweak form factors are discussed in a single pion production model
with nonresonant background terms originating from a chiral perturbation theory.
Fits to electronproton scattering F2 as well as neutrino scattering bubble chamber experimental
data are performed. Both \nuproton and \nuneutron channel data are discussed in a unified statistical model.
A new parametrization of the $N\to\Delta(1232)$ vector form factors is proposed.
In the case of model with deuteron nuclear effects fit to neutrino scattering data gives the axial mass M_{A\Delta}=0.85+0.090.08 (GeV) and
C5A(0) = 1.10+0.150.14 in accordance with GoldbergerTreiman relation. However, the consistency is spoiled when the deuteron effects are omitted
i.e. in this case the fit gives the axial mass M_{A\Delta}=0.81+0.090.09 GeV and C5A(0)=0.93+0.130.13.

Krzysztof M. Graczyk,
Relevance of TwoBoson Exchange Effect in Quasielastic Charged Current NeutrinoNucleon Interaction,
Phys. Lett. B732, 315 (2014).
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Abstract:

Twoboson exchange (TBE) correction in $\nu n \to l^ p$ and $\nu p\to l^+ n$ reactions is estimated. The TBE contribution is
given by $W\gamma$ box diagrams. The calculations are performed for 1 GeV neutrinos and for the MiniBooNE and the
T2K energy spectra. The TBE correction to the total cross section is of the order of $2\div 4\%$ (with respect to the Born
contribution) in the case of $\nu_e$ and $\overline{\nu}_e$ and $1 \div 2\%$ in the case of $\nu_\mu$ and $\overline{\nu}_\mu$.

Krzysztof M. Graczyk,
Comparison of Neural Network and Hadronic Model Predictions of TwoPhoton Exchange Effect,
Phys. Rev. C 88, 065205 (2013).
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Abstract:

Predictions for the twophoton exchange (TPE) correction to unpolarized $ep$ elastic cross section,
obtained within two different approaches, are confronted and discussed in details. In the first one the TPE correction is extracted from experimental data by applying the Bayesian neural network (BNN) statistical framework. In the other the TPE is given by box diagrams, with the nucleon and the $P_{33}$ resonance as the hadronic intermediate states. Two different form factor parametrizations for both the proton and the $P_{33}$ resonance are taken into consideration. Proton form factors are obtained from the global fit of the full model (with the TPE correction) to the unpolarized cross section data. Predictions of both methods agree well in the intermediate $Q^2$ range, $(1,3)$ GeV$^2$. Above $Q^2=3$ GeV$^2$ the agreement is on $2\sigma$ level. Below $Q^2=1$ GeV$^2$ the consistency between both approaches is broken. The values of the proton radius extracted within both models are given.
In both cases predictions for VEPP3 experiment have been obtained and confronted with the preliminary experimental results.

T. Golan, K. M. Graczyk, C. Juszczak, and J. T. Sobczyk,
Extraction of axial mass and strangeness values from the MiniBooNE neutral current elastic cross section measurement,
Phys. Rev. C 88, 024612 (2013).
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Abstract:

Results of the analysis of the MiniBooNE experiment data for the neutral current elastic neutrino scattering off the CH2
target with the NuWro Monte Carlo generator are presented. The inclusion in the analysis of the twobody current contribution leads to
the axial mass value MA=1.100.15+0.13 GeV, consistent with the older evaluations based on the neutrinodeuteron scattering data.
The strange quark contribution to the nucleon spin is estimated with the value gAs=0.40.3+0.5.

Krzysztof M. Graczyk,
TwoPhoton Exchange Effect Studied with Neural Networks,
Phys. Rev. C 84, 034314 (2011).
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Abstract:

An approach to the extraction of the twophoton exchange (TPE) correction from elastic ep scattering data is presented.
The crosssection, polarization transfer (PT), and charge asymmetry data are considered. It is assumed that the TPE correction to the PT data is negligible. The form factors and TPE correcting term are given by one multidimensional function approximated by the feedforward neural network (NN). To find a modelindependent approximation, the Bayesian framework for the NNs is adapted. A large number of different parametrizations is considered. The most optimal model is indicated by the Bayesian algorithm. The obtained fit of the TPE correction behaves linearly in ? but it has a nontrivial Q2 dependence.
A strong dependence of the TPE fit on the choice of parametrization is observed.

Krzysztof M. Graczyk, Piotr Plonski, Robert Sulej,
Neural Network Parameterizations of Electromagnetic Nucleon Form Factors,
JHEP09(2010) 053.
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Abstract:

The electromagnetic nucleon formfactors data are studied with artificial feed forward neural networks.
As a result the unbiased modelindependent formfactor parametrizations are evaluated together with uncertainties.
The Bayesian approach for the neural networks is adapted for chi2 errorlike function and applied to the data analysis.
The sequence of the feed forward neural networks with one hidden layer of units is considered.
The given neural network represents a particular formfactor parametrization. The socalled evidence
(the measure of how much the data favor given statistical model) is computed with the Bayesian framework and it is used
to determine the best form factor parametrization.

Krzysztof M. Graczyk, Danuta Kiełczewska, Paweł Przewłocki, Jan T. Sobczyk,
C5A axial form factor from bubble chamber experiments,
Phys. Rev. D80, 093001 (2009).
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Abstract:

A careful reanalysis of both Argonne National Laboratory and Brookhaven National Laboratory data for weak single pion production is done. We consider deuteron nuclear effects and normalization (flux) uncertainties in both experiments. We demonstrate that these two sets of data are in good agreement. For the dipole parametrization of $C_5^A(Q^2)$, we obtain $C_5^A(0)=1.19\pm 0.08$, $M_A=0.94\pm 0.03$~GeV.
As an application we present the discussion of the uncertainty of the neutral current 1$\pi^0$ production cross section, important for the T2K neutrino oscillation experiment.

W. M. Alberico, S. M. Bilenky, C. Giunti, K. M. Graczyk,
The ratio of e+ p scattering cross sections predicted from the global fit of elastic ep data,
J. Phys. G. Nucl. Part. Phys. 36, 115009 (2009).
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Abstract:

We present predictions for the value of the cross section ratio $\sigma(e^+p \to e^+p)/\sigma(e^p \to e^p)$, determined from our fit of the elastic $ep$ cross section and polarization data. In this fit we took into account the phenomenological twophoton exchange dispersive correction.
The cross section ratios which are expected to be measured by the VEPP3 experiment are computed. The kinematical region which will be covered by the E04116 JLab experiment is also considered. It is shown that for both experiments the predicted cross section ratios deviate from unity within more than $3\sigma$.

W. M. Alberico, S. M. Bilenky, C. Giunti, K. M. Graczyk,
Electromagnetic form factors of the nucleon: New fit and analysis of uncertainties,
Phys. Rev. C 79, 065204 (2009).
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Abstract:

Electromagnetic form factors of proton and neutron, obtained from a new fit of data, are presented. The proton form factors are obtained from a simultaneous fit to the ratio $\mu_p G_{Ep}/G_{Mp}$ determined from polarization transfer measurements and to $ep$ elastic cross section data. Phenomenological twophoton exchange corrections are taken into account. The present fit for proton was performed in the kinematical region $Q^2\in (0,6)$ GeV$^2$. Both for protons and neutrons we use the latest available data. For all form factors the uncertainties and correlations of form factor parameters are investigated with the $\chi^2$ method.

K. M. Graczyk, J. T. Sobczyk,
Lepton mass effects in weak CC single pion production,
Phys. Rev. D77, 053003 (2008).
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Abstract:

Different approaches to take into account nonzero lepton mass in the ReinSehgal model are compared. Modification of the axial current due to pion pole term are included and it is shown that they lead to large reduction of antineutrino cross section and a change of the shape of $d\sigma/dQ^2$.

K. M. Graczyk, J. T. Sobczyk,
Form Factors in the Quark Resonance Model,
Phys. Rev. D77, 053001 (2008).
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Erratum: Phys. Rev. D 79, 079903(E) (2009).
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Abstract:

Vector and axial form factors in the quark resonance model are analyzed with a combination of theoretical and phenomenological arguments. The new form of form factors is deduced from $\Delta$(1232) excitation models and available data. The vector part is shown to agree with the resonant contribution to electronproton inclusive $F_2$ data. The axial part is obtained by finding a simultaneous fit to ANL and BNL $\frac{d \sigma}{d Q^2}$ neutrino scattering data. The best fit corresponds to $C_5^A(0)=0.88$ in the Rarita Schwinger formalism.

K. M. Graczyk, C. Juszczak, J. T. Sobczyk,
QuarkHadron Duality in the ReinSehgal Model,
Nucl. Phys. A781, 227 (2007).
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Abstract:

The quarkhadron duality in CC and NC neutrino interactions is discussed under assumptions that single pion production is described accurately by
the ReinSehgal model and that it allows reconstruction of the inclusive cross section in the resonance region.
The duality is measured by means of integrals of structure functions in the Nachtmann variable for $Q^2<3$ GeV$^2$.
The results depend on the precision with which contributions from single pion production channels in the overall cross sections are known.
Several approaches to evaluate them are compared.
The duality is predicted to be seen for proton target reactions and to be absent for neutron and isoscalar targets. Twocomponent duality between resonant and valence quark contributions to structure functions is also investigated.

A. Ankowski et al.,
Energy reconstruction of electromagnetic showers from pi0 decays with the ICARUS T600 Liquid Argon TPC,
Acta Phys.Polon.B41, 103 (2010).
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A. Ankowski et al.,
Characterization of ETL 9357FLA Photomultiplier Tubes for
Cryogenic Temperature Applications,
Nucl. Instrum. Meth. A556, 146(2006).
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A. Ankowski et al.,
Measurement of throughgoing particle momentum by means of multiple scattering with the ICARUS T600 TPC
Eur.Phys.J. C48 (2006) 667.
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Krzysztof M. Graczyk,
Tau polarization in quasielastic chargedcurrent neutrino (antineutrino)nucleus scattering,
Nucl. Phys. A748, 313 (2005).
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Abstract:

The quasielastic chargedcurrent (CC) tau neutrino (antineutrino)nucleus scattering is considered.
The dependence of tau polarization on nuclearstructure effects is discussed in detail.
The description of the nucleus is based on the MeanField Theory (MFT). The ground state of nucleus
is described using the Relativistic Fermi Gas model (FG). The effective mass is introduced as well
as the ring Random Phase Approximation (RPA) effects are taken into account in the framework of relativistic mesonnucleon model. The Local Density Approximation (LDA) is used for the argon nucleus, having in mind possible application to the ICARUS experiment.
The discussion concentrates on the threshold region where the $\tau^$
can be unpolarized and the nuclear effects play an important role.

K. M. Graczyk, J. T. Sobczyk,
Algebraic solution of RPA equations for CC quasielastic neutrinonucleus scattering,
Eur. Phys. J. C31, 177 (2003).
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The algebraic solution of RPA equations nucleon reinteractions in the case of quasi elastic charged current neutrino  nucleus scattering is presented. Abelian algebra of matrices allows to extract four independent corrections to cross section separatly.Results of numerical computations are shown.

M. Amoruso, et al.,
Design, construction and tests of the ICARUS T600 detector,
Nucl. Instrum. Meth. A527, 329 (2004).
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 M. Amoruso, et al.,
Study of electron recombination in liquid Argon with the ICARUS TP,
Nucl. Instrum. Meth. A523, 275 (2004).
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 M. Antonello, et al.,
Detection of cherenkov light emission in liquid Argon,
Nucl. Instrum. Meth. A516, 348 (2004).
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M. Amoruso, et al.,
Analysis of the liquid argon purity in the ICARUS T600 TPC,
Nucl. Instrum. Meth. A516, 68 (2004).
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S. Amoruso, et al.,
Measurement of Mu decay spectrum with the ICARUS liquid argon TPC,
Eur. Phys. J. C33, 233 (2004).
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F. Arneodo, et al.,
Observation of long ionizing tracks with the ICARUS T600 first halfmodul.
Nucl. Instrum. Meth. A508, 287 (2003).
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Conference proceedings


Luis AlvarezRuso, Krzysztof M. Graczyk and Eduardo SaulSala,
Neural network study of the nucleon axial formfactor,
PoS ?? ?? ??
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Abstract:

We have performed the first Bayesian neuralnetwork analysis of neutrinodeuteron scattering
data [1]. The nucleon axial form factor has been extracted from quasielastic scattering data collected
by the Argonne National Laboratory (ANL) bubble chamber experiment using a modelindependent
parametrization. The results are in agreement with previous determinations only
when the low 0.05 < Q2 < 0.10 GeV2 region is excluded from the analysis. This suggests that
corrections from the deuteron structure may play a crucial role at low Q2, although experimental
errors in this kinematic region could have also been underestimated. With new and more precise
measurements of neutrinoinduced quasielastic scattering on hydrogen and deuterium, the present
framework would be readily applicable to unravel the axial structure of the nucleon.

Krzysztof M. Graczyk and Beata E. Kowal
Nonresonant background signal in the polarization transfer in the weak pion production off the nucleon,
Neutrino 2018 conference proceedings, (2018) Zenodo, 10.5281/zenodo.1301014
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Abstract:

Polarization transfer (PT) observables in the single pion production induced by the charged current neutrinonucleon interaction are examined within two models. The predictions are made for neutrino energy of the order of 1 GeV as well as for the T2K energy flux. It is demonstrated that the PT observables: the degree of polarization and the polarization components of outgoing fermions are sensitive to the details of the nonresonant background model. It is shown that the normal component of the polarization of the outgoing nucleon and the charged lepton are determined by the interference between the resonant (RES) and nonresonant (NB) amplitudes. Moreover, the sign of the normal component of the polarization of the charged lepton is related to the relative sign between the RES and the NB amplitudes. The presentation is based on: Phys.Rev. D97 (2018) no.1, 013001, and Acta Phys.Polon. B48, 2219 (2017).

Beata E. Kowal and Krzysztof M. Graczyk,
Single pion production in neutrinonucleon scattering studied with FORM package,
Proceedings of student poster session of the VII International Pontecorvo Neutrino Physics School (Prague, Czech Republic, August 20  September 1, 2017), edited by F. Simkovic,  Dubna: JINR, ISBN 9785953004848
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Abstract:

Two models for the single pion production induced by interactions of the neutrinos
with the nucleons are studied. The nonresonant background contribution is a subject of analysis.
It is shown that the normal component of the polarization of the charged lepton is sensitive on
the nonresonant background contribution. It is also demonstrated that the FORM language can be
utilized to evaluate all necessary transition matrix elements and the single pion production cross
sections.

Krzysztof M. Graczyk and Beata E. Kowal,
Single Pion Production Induced by NeutrinoNucleon Interactions,
Acta Phys. Polon. B48 (2017) 2219
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Abstract:

This talk presents short review of the single pion production (SPP) in
the neutrinonucleon scattering. The attention is focused on the discus
sion of the main difficulties in modeling the SPP processes. New physical
observables, which may constrain the theoretical models, are proposed.

J. Zmuda, K. M. Graczyk, C. Juszczak, J. T. Sobczyk,
NuWro Monte Carlo generator of neutrino interactions 
first electron scattering results,
Acta Phys. Polon. B46 (2015) 11, 2329
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Abstract:

NuWro Monte Carlo generator of events is presented. It is a numerical
environment containing all necessary ingredients to simulate interactions
of neutrinos with nucleons and nuclei in realistic experimental situation in
wide neutrino energy range. It can be used both for data analysis as well
as studies of nuclear effects in neutrino interactions. The first results and
functionalities of eWro  module of NuWro dedicated to electron nucleus
scattering  are also presented.

J. Żmuda, K. M. Graczyk,
Electroweak Single Pion Production and Form Factors of the Delta(1232) Resonance,
AIP. Conf. Proc. 1680 (2015) 020013
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Abstract:

We extend and review our analysis of the nucleon to Delta(1232) transition electroweak form factors from Ref. [1]. New fit of the Delta(1232) vector form factors to electronproton scattering
F2 structure function is introduced as well, leading to results different from the popular parametrization of Ref. [2]. A clear model dependence of the extracted parameters emerges.
Fit to neutrino scattering data is performed in all available isospin channels. The resulting axial mass is M_{A\Delta}=0.85^{+0.09}_{0.08} (GeV) and $C_5^A(0) = 1.10^{+0.15}_{0.14}.
The latter value is in accordance with GoldbergerTreiman relation as long as the deuteron effects are included.

Krzysztof M. Graczyk,
NDelta weak transition,
AIP Conf. Proc. 1405, (2011) 134
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Abstract:

A short review of the ReinSehgal and isobar models is presented. The attention is focused on the nucleon$\Delta$(1232) weak transition formfactors.
The results of the recent reanalyses of the ANL and BNL bubble chamber neutrinodeuteron scattering data are discussed.

P. Przewłocki, K. M. Graczyk, D. Kiełczewska, J.T. Sobczyk,
Pion production uncertainty in context of Tokai2Kamioka (T2K) experiment,
Contributed to European Strategy for Future Neutrino Physics, CERN, Geneva, Switzerland, 13 Oct 2009, pp. 250252
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Abstract:

We evaluate uncertainty of the neutral current pi0 production coming from limited
knowledge of axial formfactor. The uncertainties of the formfactor parameters
are obtained from a selfconsistent fit to the results of ANL and BNL
experiments measuring pion production free of significant nuclear effects. The
evaluated uncertainities are important for T2K background estimates.

Krzysztof M. Graczyk,
Quarkhadron duality in lepton scattering off nucleons,
AIP Conf.Proc.1222:238 (2010)
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Abstract:

The quarkhadron (QH) duality in lepton scattering off nucleons is studied with the resonance quark model. It is shown that in the case of neutrino scattering off isoscalar target the duality is simultaneously observed for charged and neutral currents $xF_1^{\nu N}$, $F_2^{\nu N}$, and $xF_3^{\nu N}$ weak structure functions.
We demonstrate that the QH duality can be useful property for modeling structure functions in the socalled resonance region. As an example it is shown that combining the relativistic quark model predictions with the duality arguments allows to construct the inclusive resonance $F_2^{ep}$ structure function.

Krzysztof M. Graczyk,
Single pion production induced by neutrinonucleon interactions,
PoS (EPSHEP 2009) 286.
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Abstract:

This talk presents some of the results of the reanalysis \cite{Graczyk:2009qm} of the bubble chamber
data for single pion production induced by neutrino scattering off deuteron.
It is shown that ANL and BNL data are statistically consistent.
The validity of the Adler relations (between $P_{33}(1232)$ resonance axial form factors) is also investigated.

Krzysztof M. Graczyk, D. Kiełczewska, Jan T. Sobczyk,
C5A form factor from ANL experiment,
Acta. Phys. Polon. B40, (2009) 2565.
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Abstract:

$C_5^A(Q^2)$ axial form factor is extracted from the ANL neutrinodeuteron
scattering data with deuteron structure effects taken into consideration.
The best fit of the $C_5^A(Q^2)$ axial form factor is obtained assuming dipole
parametrization with $C_5^A(0)=1.13\pm0.15$ and $M_A=0.94\pm 0.08$ GeV.

K. M. Graczyk,
Resonance contribution to single pion production in neutrinonucleon scattering,
Proceedings of 27th International Workshop on Nuclear Theory, BM Trade Ltd., pp. 95105 (2008) ISSN: 13132822, arXiv:0810.1247
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Abstract:

Single pion production in neutrinonucleon scattering is discussed. The neutrino energies characteristic for T2K project are considered. Two new parameterizations of $C_5^A$ axial form factor are proposed. Both of them are obtained in simultaneous fit to ANL and BNL data.
One of them (which fits better to BNL data) leads to $d\sigma/dQ^2$ differential cross section which is significantly reduced at low $Q^2$.

Krzysztof M. Graczyk, J. T. Sobczyk,
On description of D(1232) region in the ReinSehgal model,
AIP Conf.Proc.967, 205 (2007).
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Abstract:

New vector and axial form factors in the ReinSehgal model are proposed.
The vector part is constructed after experimental
fits of the helicity amplitudes for electroproduction of Delta(1232) resonance.
The axial part is calculated after Q2 distribution of events in the ANL.

Krzysztof M. Graczyk,
Analysis of the ReinSehgal model in the context of the quarkhadron duality,
Acta. Phys. Polon. B37, 2321 (2006).
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Abstract:

An analysis of the ReinSehgal model in the context of the quarkhadron duality hypothesis is presented.
The resonance region structure functions reconstructed from the
ReinSehgal model at different values of Q2RES are compared with the
DIS structure functions calculated at higher Q2DIS.
The ratios of corresponding integrals in the Nachtman variable
are also calculated and presented as functions of Q2RES.
The obtained functions are approximately flat for
Q2RES > 0.5 GeV2 but the quarkhadron duality is not observed.

K. M. Graczyk, C. Juszczak, J. T. Sobczyk,
Appearance of quarkhadron duality in the ReinSehgal model,
Nucl. Phys. B (Proc. Suppl.) 159, 241 (2006).
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Abstract:

Quarkhadron duality in neutrinonucleon reactions is investigated under the assumption that cross sections
in the resonance region are given by the ReinSehgal model. The quantitative analysis of the duality is done by
means of appropriate integrals of the structure functions in the Nachtmann variable.
We conclude that with the definition of the resonance region $W\in (M+m_{\pi}, 2$ GeV) the duality holds for neutrinoproton reaction $F_2$ structure function
for $Q^2\in (0.5, 3)$ GeV$^2$ and it is absent for neutrinoneutron reaction.

K.M. Graczyk,
Tau polarization in charged current neutrinonucleon Deep Inelastic Scattering,
Nucl. Phys. (Proc. Suppl.) 139, 150 (2005).
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Abstract:

Numerical results for the degree of polarization of \tau^ produced in (CC) neutrino  nucleon Deep Inelastic Scattering (DIS) are presented.
Calculations are done in the threshold region, where the \tau^ scattered by the small angles and can be partially polarized.
The cross sections and polarization are calculated by using the GRV98 parton distributions functions (PDF's) and the GRV98 with modifications of
A. Bodek at.al.

J.T. Sobczyk, J.A. Nowak, K.M. Graczyk,
WRONG  Wrocław neutrino generator of events for single pion production,
Nucl. Phys. B (Proc. Suppl.) 139, 266 (2005).
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Abstract:

We constructed a new Monte Carlo generator of events for neutrino CC single pion production on free nucleon targets.
The code uses dynamical models of the DIS with the PDFs modified according to the recent JLab data and of the Delta excitation.
A comparison with experimental data was done in three channels for the total cross sections and for the distributions of events in invariant hadronic mass.

Preprints


K.M. Graczyk,
Local Density Approximations in chargedcurrent quasielastic neutrino on Oxygen, Argon and Iron scattering,
nuclth/0401053.
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Talks


Analysis of the ReinSehgal model in the context of the quarkhadron duality.
XX Max Born Symposium
Nuclear effects in neutrino interactions,
Wrocław, Poland, December 710, 2005.

On Description of the Resonance Region in the FKR Model.
Fifth International Workshop on NeutrinoNucleus Interactions in the FewGeV Region:
NuInt07 Conference,
Fermilab (Batavia), Illinois, USA 30 May – 3 June, 2007.

Single pion production in neutrinonucleon scattering,
Meeting of the INFN Theory Collaboration PI31,
ECT* Trento, Italy, 2728 March, 2008.

Resonance contribution to single pion production in neutrinonucleon scattering
,
27th International Workshop on Nuclear Theory,
Rila Mountains, Bulgaria, 2228 June, 2008.

C5A axial form factor determined from the bubble chamber experiments,
Neutrino interactions: from theory to
Monte Carlo simulations, 45th Karpacz Winter School of Theoretical Physics,
Lądek Zdrój, Poland, February 211, 2009.

Single pion production induced by neutrinonucleon interactions.
The 2009 Europhysics Conference on High Energy Physics, APS HEP 2009,
Cracow, Poland, 1622 July, 2009.

QuarkHadron Duality in lepton scattering off nuclei.
N u F a c t 0 9  11th International Workshop on
Neutrino Factories, Superbeams and Beta Beams,
Chicago, USA, 2025 July, 2009. Invited talk

NDelta Weak Transition.
Seventh International Workshop on NeutrinoNucleus Interactions in the FewGeV Region:
NuInt11 conference,
711 March, 2011, Dehradun, India. Invited talk

Radiative Corrections in Charged Current Quasielastic νN scattering.
International Workshop on Neutrino Factories Super Beams and Beta Beams, NUFACT13,
1924 August, 2013, IHEP, Beijing, China.

Twoboson exchange in (quasi)elastic lepton scattering off nucleons.
Theory Meeting Experiment 2014 (TMEX), Neutrinos and Cosmos,
Warsaw, 35 September 2014.

Neutrinonucleon/nucleus interactions,
Astroparticle physics in Poland,
Warsaw, May 1113, 2015.

Modeling nucleon form factors with methods of Bayesian neural networks
Information and statistics in nuclear experiment and theory: ISNET3 Workshop,
1620 November, 2015, ECT* Trento, Italy. Invited talk

Pion production induced by neutrinonucleon interactions,
Matter To The Deepest
Recent Developments In Physics Of Fundamental Interactions
XLI International Conference of Theoretical Physics
,
38 September 2017, Podlesice, Poland. Invited talk

Nucleon axial form factor from a Bayesian neuralnetwork analysis of neutrinoscattering data,
Uncertainty Quantification (UQ) at the Extremes (ISNET6)
,
812 October 2018, Darmstadt, Germany. Invited talk

Poster presentations


Tau polarization in charged current neutrinonucleon Deep Inelastic Scattering
Third International Workshop on NeutrinoNucleus Interactions in few GeV region: NuInt04 conference,
LNGS, Gran Sasso, Italy, 1721 March 2004.

Appearance of quarkhadron duality in the ReinSehgal model.
Fourth International Workshop on NeutrinoNucleus Interactions in the FewGeV Region,
Okayama, 2629 Septemebr, 2005.

The degree of the polarization of the Tau lepton produced in the NeutrinoNucleus Scattering.
VII School on NonAccelerator Astroparticle Physics,
ICTP, Trieste, Italy, 26 July – 6 August, 2004.

Electron Interactions in NuWro,
presented by Cezary Juszczak,
Theory Meeting Experiment 2014 (TMEX), Neutrinos and Cosmos,
Warsaw, 35 September 2014.

Single pion production in neutrinonucleon scattering studied with FORM package,
presented by Beata E. Kowal,
VII International Pontecorvo Neutrino Physics School,
Prague, Czech Republic, August 20  September 1, 2017

Nonresonant background signal in the polarization transfer in the weak pion production off the nucleon,
Neutrino 2018,
Heidelberg, Germany, 49 June, 2018

Seminars


Neutrina Najdziwniejsze cząstki materii
Seminar for high school students,
Wrocław, Poland, 12112005.

Analysis of the ReinSehgal model in the context of quarkhadron duality,
,
JINR Dubna, Russia, 12052006.

Modelowanie oddziaływania neutrin z materią w konfrontacji z eksperymentem,
Warszawa, 23032007.

Badanie oscylacji neutrin w eksperymencie T2K
,
Meeting of Astroparticle and Neutrino polish communities: Perspektywy astrofizyki cząstek,
Kraków, Poland, (1418)102007

Single pion production in neutrinonucleon scattering
,
INFN and University of Torino, 20022008.

Produkcja pojedynczych pionów w oddziaływaniu neutrinodeuteron  reanaliza
danych z eksperymentów ANL i BNL
,
Warszawa, Seminarium Warszawskiej Grupy Neutrinowej, IPJ, 20032009.

Neutrina  boski posłaniec tajemnic natury,
Koło naukowe „Migacz”, Wydział Fizyki i Astronomii, Uniwersytet Wrocławski, 12102011

Neutrino Physics Division scientific activity,
Winter Kindergarden, Lądek Zdrój, 10022013.

Neural Network and Theoretical Predictions of TPE Effect in Elastic ep Scattering,
Katowice, seminarium Zakładu Teorii Pola i Cząstek Elementarnych, Uniwersytet Śląski, Instytut Fizyki, 14052013.

TwoPhoton Exchange Effect in Elastic ep Scattering,
Warszawa, Seminarium Teorii Oddziaływań Elementarnych, Instytut Fizyki Teoretycznej, Uniwersytet Warszawski, 13012014.

Bayesian Inference in Investigation of LeptonNucleon Interactions,
Wrocław, Seminarium Instytutowe, Instytut Fizyki Teoretycznej, Uniwersytet Wrocławski, 14102016.