N. N. Nikolaev

Polarizing a stored proton beam by spin flip? (2009)

One of the well known effects of the asymptotic freedom is splitting of the leading-$\log$ BFKL pomeron into a series of isolated poles in complex angular momentum plane. Following our earlier works...

Oellers, D., Barion, L., Barsov, S., Bechstedt, U., Benati, P., Bertelli, S., ...

We discuss polarizing a proton beam in a storage ring, either by selective removal or by spin flip of the stored ions. Prompted by recent, conflicting calculations, we have carried out a measurement...

Unitarity constraints for DIS off nuclei: predictions for electron-ion colliders (2006)

Nikolaev, N. N., Schäfer, W., Zakharov, B. G., Zoller, V. R.

Future electron-ion colliders (eIC) will focus on the unitarity properties of deep inelastic scattering (DIS) in the limit of strong nuclear absorption. Strong nuclear shadowing and a large abundance...

Constituent quark theory of multiple production on nuclear targets (2006)

Nikolaev, N N, Ostapchuk, A Ya

Charged current diffractive structure functions (2006)

Genovese, M., Bertini, M., Nikolaev, N.N., Zakharov, B.G.

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Inelastic particle-nucleus interactions at high energies (2006)

Nikolaev, N N, Ostapchuk, A Ya, Zoller, V R

Unitarity cutting rules for the nucleus excitation and topological cross sections in hard production off nuclei from nonlinear k_t-factorization (2006)

Quenching of Leading Jets and Particles: the p_t Dependent Landau-Pomeranchuk-Migdal effect from Nonlinear k_t Factorization (2006)

At the partonic level, a typical final state in small-x deep inelastic scattering off nuclei and hard proton-nucleus collisions can be characterized by the multiplicity of color-excited nucleons....

Glue in the pomeron from nonlinear k_\perp-factorization (2006)

We report the first derivation of the Landau-Pomeranchuk-Migdal effect for leading jets at fixed values of the transverse momentum p_t in the beam fragmentation region of hadron-nucleus collisions...

Nikolaev, N. N., Schäfer, W., Zakharov, B. G., Zoller, V. R.

We derive the nonlinear k_\perp-factorization for the spectrum of jets in high-mass diffractive deep inelastic scattering as a function of three hard scales - the virtuality of the photon Q^2, the...

Polarization Buildup of Stored Protons and Antiprotons: Filtex Result and Implications for Pax at Fair (2006)

Nikolaev, N. N., Pavlov, F. F.

The spin filtering by a multiple passage of a stored beam through a polarized internal gas target is a unique possibility of polarizing high luminosity beam of antiprotons to a high degree of...

Diffractive Vector Meson Production at HERA: from soft to hard QCD (2006)

I.P. Ivanov, DESY Forschung Hochenergiephysik, N.N. Nikolaev, A.A. Savin

Journal article

Spin Filtering in Storage Rings (2005)

Nikolaev, N. N., Pavlov, F. F.

The spin filtering in storage rings is based on the multiple passage of a stored beam through a polarized internal gas target. Apart from the polarization by transmission, a unique geometrical...

Nonlinear $k_{\perp}$-factorization: a new paradigm for an in-nucleus hard QCD (2005)

Nikolaev, N. N., Schäfer, W., Zakharov, B. G., Zoller, V. R.

We review the origin, and salient features, of the breaking of the conventional linear $k_{\perp}$-factorization for an in-nucleus hard pQCD processes. A realization of the nonlinear...

Nonlinear k_\perp-factorization for Gluon-Gluon Dijets Produced off Nuclear Targets (2005)

Nikolaev, N. N., Schäfer, W., Zakharov, B. G.

The origin of the breaking of conventional linear k_\perp-factorization for hard processes in a nuclear environment is by now well established. The realization of the nonlinear nuclear...

Nonlinear k_\perp-factorization for Quark-Gluon Dijet Production off Nuclei (2005)

Nikolaev, N. N., Schäfer, W., Zakharov, B. G., Zoller, V. R.

The breaking of conventional linear k_\perp-factorization for hard processes in a nuclear environment is by now well established. Here we report a detailed derivation of the nonlinear...

Nonuniversality Aspects of Nonlinear k_\perp-factorization for Hard Dijets (2005)

Nikolaev, N. N., Schäfer, W., Zakharov, B. G.

The origin of the breaking of conventional linear k_\perp-factorization for hard processes in a nuclear environment is by now well established. The realization of the nonlinear nuclear...

Diffractive Vector Meson Production at HERA: from Soft to Hard QCD (2005)

Ivanov, I. P., Nikolaev, N. N., Savin, A. A.

Experimental results from HERA on diffractive vector meson production and their theoretical interpretation within microscopic QCD are reviewed with an emphasis on the BFKL color dipole and...

Hard Scattering in a Nuclear Environment: Farewell to Linear $k_{\perp}$-Factorization (2005)

Nikolaev, N. N., Schäfer, W., Zakharov, B. G., Zoller, V. R.

We discuss a dramatic change brought into the pQCD description of hard processes in a nuclear environment by a large thickness of heavy nuclei. It breaks the familiar linear $k_{\perp}$-factorization...

Nonuniversality aspects of nonlinear k(T)-factorization for hard dijets (2005)

Nikolaev, N. N., Schäfer, W., Zakharov, B. G.

This version is available at the following Publisher URL: http://prl.aps.org

"Breaking of k[perpendicular]-factorization for single jet production off nuclei" (2005)

QCD physics with polarized antiprotons at GSI (2004)

This version is available at the following Publisher URL: http://prd.aps.org

Lenisa, P., Rathmann, F., Anselmino, M., Chiladze, D., Contalbrigo, M., Dalpiaz, P. F., ...

A polarized antiproton beam at the Facility for Antiproton and Ion Research, proposed by the PAX collaboration, will open a window to new physics uniquely accessible at the new High Energy Storage...

Fate of k_perp-factorization for hard processes in nuclear environment (2004)

Breaking of k_\perp-factorization for Single Jet Production off Nuclei (2004)

Large thickness of heavy nuclei brings in a new scale into the pQCD description of hard processes in nuclear environment. The familiar linear $k_{\perp}$-factorization breaks down and must be...

Multiple exchanges in lepton pair production in high--energy heavy ion collisions (2004)

The linear k_\perp-factorization is part and parcel of the pQCD description of high energy hard processes off free nucleons. In the case of heavy nuclear targets the very concept of nuclear parton...

Bartos, E., Gevorkyan, S. R., Kuraev, E. A., Nikolaev, N. N.

The recent analysis of nuclear distortions in DIS off nuclei revealed a breaking of the conventional hard factorization for multijet observable. The related pQCD analysis of distortion effects for...

Evolution of high-mass diffraction from the light quark valence component of the pomeron (2004)

Nikolaev, N. N., Schäfer, W., Zakharov, B. G., Zoller, V. R.

We analyze the contribution from excitation of the $(q\bar q)(f\bar f),(q\bar q)g_1...g_n(f\bar f)$ Fock states of the photon to high mass diffraction in DIS. We show that the large $Q^2$ behavior of...

Color dipoles and k_t factorization for nuclei (2004)

Nikolaev, N. N., Schäfer, W., Zakharov, B. G., Zoller, V. R.

We discuss applications of the color dipole approach to hard processes on nuclei. We focus on the relation to k_t--factorisation and the role of a nuclear unintegrated gluon distribution in single--...

Why Breakup of Photons and Pions into Forward Dijets Is so Different: Predictions from Nonlinear Nuclear k_t-factorization (2004)

Nikolaev, N. N., Schäfer, W., Zakharov, B. G., Zoller, V. R.

Based on an approach to non-Abelian propagation of color dipoles in a nuclear medium we formulate a nonlinear k_t-factorization for the breakup of photons and pions into forward hard dijets in terms...

Accessing transversity via J/Psi production in polarized p-pbar interactions (2004)

Anselmino, M., Barone, V., Drago, A., Nikolaev, N. N.

We discuss the possibility of a direct access to transversity distributions by measuring the double transverse spin asymmetry A_TT in p pbar --> J/Psi + X --> l^- l^+ + X processes at future GSI-HESR...

Impact of saturation on s-channel helicity nonconservation for diffractive vector mesons (2003)

Ivanov, I. P., Nikolaev, N. N., Schäfer, W.

As Glauber has shown in 1959, the spin-flip phenomena caused by the conventional spin-orbit interaction do vanish in the scattering off heavy, strongly absorbing nuclei. On the other hand, the origin...

Ultraperipheral photoproduction of vector mesons in the nuclear Coulomb field and the size of neutral vector mesons (2003)

Gevorkyan, S. R., Ivanov, I. P., Nikolaev, N. N.

We point out a significance of ultraperipheral photoproduction of vector mesons in the Coulomb field of nuclei as a means of measuring the radius of the neutral vector meson. This new contribution to...

Nonlinear kT factorization for Forward Dijets in DIS off Nuclei in the Saturation Regime (2003)

Nikolaev, N. N., Schäfer, W., Zakharov, B. G., Zoller, V. R.

We develop the QCD description of the breakup of photons into forward dijets in small-x deep inelastic scattering off nuclei in the saturation regime. Based on the color dipole approach, we derive a...

High Density QCD, Saturation and Diffractive DIS (2002)

Ivanov, I. P., Nikolaev, N. N., Schäfer, W., Zakharov, B. G., Zoller, V. R.

We review a consistent description of the fusion and saturation of partons in the Lorentz-contracted ultrarelativistic nuclei in terms of a nuclear attenuation of color dipole states of the photon...

Lectures on Diffraction and Saturation of Nuclear Partons in DIS off Heavy Nuclei (2002)

Ivanov, I. P., Nikolaev, N. N., Schäfer, W., Zakharov, B. G., Zoller, V. R.

The Lorentz contraction of ultrarelativistic nuclei entails a spatial overlap and fusion (recombination, saturation) of partons belonging to different nucleons at the same impact parameter. In these...

Spontaneously Broken Chiral Symmetry and Hard QCD Phenomena (2002)

Amarian, M. J., Braun, V. M., Brodsky, S. J., Collins, J., Diehl, M., Ecker, G., ...

These are the mini-proceedings of the workshop ``Spontaneously Broken Chiral Symmetry and Hard QCD Phenomena" held at the Physikzentrum Bad Honnef from July 15 to 19, 2002. Every author presents a...

High Density QCD and Saturation of Nuclear Partons (2002)

Ivanov, I. P., Nikolaev, N. N., Schäfer, W., Zakharov, B. G., Zoller, V. R.

We review the recent finding of the two-plateau momentum distribution of sea quarks in deep inelastic scattering off nuclei in the saturation regime. The diffractive plateau which dominates for small...

Possibility of the odderon discovery via observation of charge asymmetry in the diffractive pi+pi- production at HERA (2002)

Ginzburg, I. F., Ivanov, I. P., Nikolaev, N. N.

The interference between the Pomeron and possible odderon mechanisms of diffractive pi+pi- photoproduction results in charge asymmetry of the produced pions. The observation of charge asymmetry of...

Saturation of Nuclear Partons: the Fermi Statistics or Nuclear Opacity? (2002)

Nikolaev, N. N., Schäfer, W., Zakharov, B. G., Zoller, V. R.

We derive the two-plateau momentum distribution of final state (FS) quarks produced in deep inelastic scattering (DIS) off nuclei in the saturation regime. The diffractive plateau which dominates for...

Diffractive Hard Dijets and Nuclear Parton Distributions (2002)

Ivanov, I. P., Nikolaev, N. N., Schäfer, W., Zakharov, B. G., Zoller, V. R.

Diffraction plays an exceptional role in DIS off heavy nuclei. First, diffraction into hard dijets is an unique probe of the unintegrated glue in the target. Second, because diffraction makes 50 per...

Diffractive Vector Meson Production in k_t-Factorization Approach (2002)

Multiple lepton pair production in relativistic ion collisions (2002)

We describe the current status of the diffractive vector meson production calculations within the k_t-factorization approach. Since the amplitude of the vector meson production off a proton is...

Bartos, E., Gevorkyan, S. R., Kuraev, E. A., Nikolaev, N. N.

We apply the Sudakov technique to description of the multiple production of lepton pairs in peripheral collisions of ultrarelativistic heavy ions. For heavy ions with $Z_1\alpha\sim Z_2\alpha\ll 1$...

From soft to hard regime in elastic pion-pion scattering above resonances (2001)

Szczurek, A., Nikolaev, N. N., Speth, J.

We discuss the onset of the dominance of the Glauber-Gribov-Landshoff (GGL) component of pQCD hard two-gluon (2G) exchange contribution to hard elastic $\pi\pi$ scattering at moderate energies . Such...

Connection between Diffraction and Small-$x$ (2001)

Diffractive DIS: Where Are We? (2001)

A brief review of the modern QCD theory of diffractive DIS is given.

Possible Odderon discovery at HERA via charge asymmetry in the diffractive pi+pi- production (2001)

A brief review of the modern QCD theory of diffractive DIS is given. The recent progress has been remarkably rapid, all the principal predictions from the color dipole approach to diffraction - the...

Ivanov, I. P., Nikolaev, N. N., Ginzburg, I. F.

We discuss how the evasive Odderon signal can be enhanced by final state interactions. We suggest the charge asymmetry of pion spectra in diffractive pi+pi- photoproduction as a promising signature...

The lepton pair production in heavy ion collisions in perturbation theory (2001)

Bartos, E., Gevorkyan, S. R., Kuraev, E. A., Nikolaev, N. N.

We derive the first terms in the amplitude of lepton pair production in the Coulomb fields of two relativistic heavy ions. Using the Sudakov technique, which very simplify the calculations in...

Unifying aspects of polarization of vector mesons from hard production in DIS and at Tevatron (2001)

Mapping the proton unintegrated gluon distribution in dijets correlations in real and virtual photoproduction at HERA (2000)

Virtual photons have both the transverse and longitudinal polarization. In the inclusive DIS the impact of longitudinal photons, quantified by R=sigmaL/\igmaT sim 0.2, is marginal, but in diffractive...

Szczurek, A., Nikolaev, N. N., Schäfer, W., Speth, J.

We discuss how the dijet azimuthal correlations in DIS and real photoproduction at HERA probe the differential (unintegrated) gluon distribution in the proton. We find a strong dependence of the...

Diffractive Vector Mesons in DIS: Meson Structure and QCD (2000)

Small-x Structure Functions and QCD Pomeron (2000)

I review the modern status of QCD theory of diffractive vector meson production with the focus on shrinkage of photons with Q2 and (Q2+mV2)$scaling, j-plane properties of the QCD pomeron and Regge...

Coherent production of hard dijets on nuclei in QCD (2000)

The recent progress in color BFKL-Regge phenomenology of small-x DIS on nucleons, pions and photons is reviewed

Nikolaev, N. N., Schäfer, W., Schwiete, G.

We formulate the perturbative QCD approach to coherent diffractive dijet production in pion-nucleon and pion-nucleus collisions at high energy. For hard dijets the Pomeron splitting mechanism in...

Anatomy of the Proton Structure Functions in $\kappa$-factorization (2000)

Diffractive Vector Meson Production In A Unified $\kappa$-Factorization Approach (2000)

We present the first experiment-based parameterization of differential gluon structure function, which is called upon in many applications. We compare $\kappa$-factorization and DGLAP approaches and...

Anatomy of the differential gluon structure function of the proton from the experimental data on F_2p (2000)

In the framework of the $\kappa$-factorization approach and on the basis of recently determined DGSF, we calculated the production rates of ground and excited (2S and D wave) states of vector mesons...

Final state interactions in $^{4}$He(e,e$^\prime$p)$^{3}$H at large proton energy (2000)

The use of the differential gluon structure function of the proton ${\cal F}(x,Q^{2})$ introduced by Fadin, Kuraev and Lipatov in 1975 is called upon in many applications of small-x QCD. We report...

Benhar, O., Nikolaev, N. N., Speth, J., Usmani, A. A., Zakharov, B. G.

At large proton energy, the final state interactions of the knocked out nucleon in $\eep$ reactions off nuclear targets can be described within the eikonal approximation, treating the spectator...

Predicitions for high-energy real and virtual photon-photon scattering from color dipole BFKL-Regge factorization (2000)

Nikolaev, N. N., Speth, J., Zoller, V. R.

High-energy virtual photon-virtual photon scattering can be viewed as interaction of small size color dipoles from the beam and target photons, which makes $\gamma^{*}\gamma^{*}, \gamma^{*}\gamma$...

How open charm production and scaling violations probe the rightmost hard BFKL pole exchange (2000)

The color dipole BFKL-Regge expansion: from DIS on protons to pions to rise of hadronic cross sections (1999)

In 1994 Zakharov and the present authors argued that in color dipole (CD) BFKL approach to DIS excitation of open charm at moderately large Q2 is dominated by hard BFKL exchange. In view of the rapid...

Nikolaev, N. N., Speth, J., Zoller, V. R.

As noticed by Fadin, Kuraev and Lipatov in 1975 incorporation of asymptotic freedom into the BFKL equation splits the QCD pomeron into a series of isolated poles in complex angular momentum plane....

Nuclear-Medium Modification of the Rho(1S)- and Rhoprim(2S)-Mesons in Coherent Photo- and Electroproduction: Coupled Channel Analysis (1999)

Nikolaev, N. N., Speth, J., Zakharov, B. G.

We study medium modifications of the dilepton mass spectrum in coherent photo- and electroproduction of the Rho(1S)- and Rhoprim(2S)-meson resonances on nuclear targets. The analysis is performed...

Helicity Flip in Diffractive DIS (1999)

Spin Dependence of Diffractive Vector Meson Production (1999)

I review new results on s-channel helicity nonconservation (SCHNC) in diffractive DIS. I discuss how by virtue of unitarity diffractive DIS gives rise to spin structure functions which were believed...

Spin dependence of diffractive DIS (1999)

I review the recent progress in the theory of s-channel helicity nonconservation (SCHNC) effects in diffractive DIS. SCHNC in diffractive vector meson production is an unique probe of the spin-orbit...

Intrinsic $k_{\perp}$ in the pomeron (1999)

I review the recent progress in the theory of s-channel helicity nonconservation (SCHNC) effects in diffractive DIS including the unitarity driven demise of the Burkhardt-Cottingham sum rule and...

Diffraction driven steep rise of spin structure function $g_{LT}=g_{1}+g_{2}$ at small x and DIS sum rules (1999)

In a consistent QCD approach to diffractive DIS gluons in the pomeron have soft $z_{g}$ distribution and very broad intrinsic $k_{\perp}$ distribution. The latter has not yet been incorporated into...

Ivanov, I. P., Nikolaev, N. N., Pronyaev, A. V., Schäfer, W.

We derive a unitarity relationship between the spin structure function $g_{LT}(x,Q^{2})=g_{1}(x,Q^{2})+g_{2}(x,Q^{2})$, the LT interference diffractive structure function and the spin-flip coupling...

Diffractive S and D-wave vector mesons in deep inelastic scattering (1999)

Precocious asymptopia for charm from the running BFKL (1998)

We derive helicity amplitudes for diffractive leptoproduction of the S and D wave states of vector mesons. We predict a dramatically different spin dependence for production of the S and D wave...

The Running BFKL: Resolution of Caldwell's Puzzle (1998)

The running BFKL equation gives rise to a series of moving poles in the complex j-plane. Corresponding eigenfunctions (color dipole cross sections) are the oscillating functions of the color dipole...

Do the E866 Drell Yan data change our picture of the chiral structure of the nucleon ? (1998)

The HERA data on the proton structure function, $F_2(x,Q^2)$, at very small $x$ and $Q^2$ show the dramatic departure of the logarithmic slope, $\partial F_2/\partial\log Q^2$, from theoretical...

Nikolaev, N. N., Sch{ä}fer, W., Szczurek, A., Speth, J.

We revisit the evaluation of the pionic mechanism of the $\bar{u}-\bar{d}$-asymmetry in the proton structure function. Our analysis is based on the extended AGK unitarity relation between...

Azimuthal asymmetry as a new handle on $\sigma_{L}/\sigma_{T}$ in diffractive DIS (1998)

Nikolaev, N. N., Pronyaev, A. V., Zakharov, B. G.

We propose a new method of the determination of $R^{D}=\sigma_{L}^{D}/\sigma_{T}^{D}$ from the dependence of the diffractive cross section on the azimuthal angle between the electron scattering and...

MEASUREMENT OF LINES IN POLYGONOMETRIC OPERATIONS WITH LENGTH FINDER AD-1 (IZMERENIE LINII V POLIGONOMETRICHESKIKH KHODAKH DLINOMEROM AD-1), (1998)

Rykhlyuk,E. I., Zebode,I. V., Krongauz,V. Sh., Nikolaev,N. N.

The translation is a description of the length-finder AD-1 and the method used in finding the measurement of lines in first and second order polygonometry. Without this instrument it is necessary to...

Diffractive vector mesons beyond the s-channel helicity conservation (1998)

Kuraev, E. V., Nikolaev, N. N., Zakharov, B. G.

We derive a full set, and determine the twist, of helicity amplitudes for diffractive production of light to heavy vector mesons in deep inelastic scattering. For large $Q^{2}$ all helicity...

Predictions for the forward cone in diffractive DIS (1998)

Nikolaev, N. N., Pronyaev, A. V., Zakharov, B. G.

We calculate the diffraction slope $B_{D}$ for diffractive DIS. We find a counterintuitive rise of $B_{D}$ from exclusive diffractive excitation of vector mesons to excitation of continuum states...

Summary of the Diffractive Working Group at DIS98 (1998)

Goussiou, A., McDermott, M., Nikolaev, N. N., Roosen, R., Piotrzkowski, K.

Recent experimental and theoretical developments in the understanding of high energy diffraction, presented in the working group on diffraction at DIS98 in Brussels, are summarised. A template,...

Diffraction in Charged Current DIS (1998)

Bertini, M., Genovese, M., Nikolaev, N. N., Zakharov, B. G.

We present the QCD calculation of the diffractive structure function for charged current DIS. In particular we analyse the perturbatively tractable excitation of heavy quarks. We emphasize the...

Charged Current Diffractive Structure Functions (1998)

Bertini, M., Genovese, M., Nikolaev, N. N., Zakharov, B. G.

We present our study of the diffraction in charged current DIS. We analyse the perturbatively tractable excitation of heavy quarks, emphasizing the peculiarities of the Regge factorization breaking...

Charged current diffractive structure functions (1998)

Genovese, M., Bertini, M., Nikolaev, N.N., Zakharov, B.G.

Twist-4 effects and Q$^2$ dependence of diffractive DIS (1998)

Bertini, M., Genovese, M., Nikolaev, N.N., Pronyaev, A.V., Zakharov, B.G.

Charged current diffractive structure functions (1998)

Genovese, M., Bertini, M., Nikolaev, N.N., Zakharov, B.G.

Twist-4 effects and Q$^2$ dependence of diffractive DIS (1998)

Bertini, M., Genovese, M., Nikolaev, N.N., Pronyaev, A.V., Zakharov, B.G.

The diffraction cone for exclusive vector meson production in deep inelastic scattering (1997)

Nemchik, J., Nikolaev, N. N., Predazzi, E., Zakharov, B. G., Zoller, V. R.

We develop the color dipole gBFKL phenomenology of a diffraction cone for photo- and electroproduction $\gamma^{*}N \to VN$ of heavy vector mesons (charmonium & bottonium) at HERA and in fixed target...

Leading proton spectrum from DIS at HERA (1997)

Szczurek, A., Nikolaev, N. N., Speth, J.

The QCD hardness scale for secondary particles ($h$) production in semi-inclusive deep inelastic scattering (DIS), $e p \to e' X h$, gradually decreases from $Q^{2}$, the photon virtuality which...

Twist-4 effects and $Q^{2}$ dependence of diffractive DIS (1997)

Bertini, M., Genovese, M., Nikolaev, N. N., Pronyaev, A. V., Zakharov, B. G.

In this letter we report the direct perturbative QCD evaluation of twist-4 effects in diffractive DIS. They are large and have a strong impact on the $Q^2$ dependence of diffractive structure...

Absorptive corrections to the one pion exchange and measurablity of the small-x pion structure function at HERA (1997)

Nikolaev, N. N., Speth, J., Zakharov, B. G.

We compaWe compare the absorptive corrections to the one pion exchange in $pp\to Xn$ and $ep\to e'Xn$ reactions. It is shown that the absorption is stronger in the case of $pp$ collision. The...

The BFKL-Regge Phenomenology of Deep Inelastic Scattering (1997)

Nonvanishing tensor polarization of sea quarks in polarized deuterons (1996)

We calculate the Regge trajectories of the subleading BFKL singularities and eigenfunctions for the running BFKL pomeron in the color dipole representation. We obtain a viable BFKL-Regge expansion of...

Nikolaev, N. N., Schaefer, W.

We propose two new sources of a substantial tensor polarization of sea partons in the deuteron: the diffractive nuclear shadowing which depends on the alignment of nucleons in the polarized deuteron...

The partonic structure of the generalized BFKL pomeron: an overview (1996)

Genovèse, M, Nikolaev, N N, Zakharov, B G

Vector Meson production in ep -> epV (1996)

Koepf, W., Landshoff, P. V., Levin, E. M., Nikolaev, N. N.

The diffractive production of vector mesons in ep interactions at low x is a subject of heated debates. This chapter consists of four contributions written by the original authors and expresses the...

Diffraction in DIS on nuclear targets (1996)

Nikolaev, N. N., Schaefer, W., Zakharov, B. G., Zoller, V. R.

We discuss the implications of a strong enhancement of diffraction for multiproduction in DIS off nuclear targets. The predicted effects are large and observable at HERA. We present the prediction of...

Diffractive DIS: back to triple-Regge phenomenology? (1996)

Nikolaev, N. N., Schaefer, W., Zakharov, B. G.

We discuss the factorization breaking effects caused by the contribution to large rapidity gap events from DIS on secondary reggeons. Based on the triple-Regge phenomenology of hadronic diffraction...

On the missing momentum dependence of the color transparency effects in (e,e'p) scattering (1996)

Benhar, O., Fantoni, S., Nikolaev, N. N., Speth, J., Usmani, A. A., Zakharov, B. G.

We explore the missing momentum dependence of the CT effects in quasielastic (e,e'p) scattering. We develop the coupled-channel multiple-scattering theory (CCMST) description of final-state...

Glauber theory of initial- and final-state interactions in (p,2p) scattering (1996)

Benhar, O., Fantoni, S., Nikolaev, N. N., Speth, J., Usmani, A. A., Zakharov, B. G.

We develop the Glauber theory description of initial- and final-state interactions (IFSI) in quasielastic A(p,2p) scattering. We study the IFSI-distortion effects both for the inclusive and exclusive...

Diffractive DIS from the Color Dipole BFKL Pomeron (1996)

Color dipole phenomenology of diffractive electroproduction of light vector mesons at HERA (1996)

We review the recent progress in the theory of diffractive DIS, focusing on predictions of strong breaking of the Ingelman-Schlein-Regge factorization and the related breaking of the GLDAP evolution...

Nemchik, J., Nikolaev, N. N., Predazzi, E., Zakharov, B. G.

We develop the color dipole phenomenology of diffractive photo- and electroproduction $\gamma^{*}\,N\rightarrow V(V')\,N$ of light vector mesons ($V(1S) = \phi^0, \omega^0, \rho^0$) and their radial...

Anomalies in Diffractive Electroproduction of 2S Radially Excited Light Vector Mesons at HERA (1996)

Nemchik, J., Nikolaev, N. N., Predazzi, E., Zakharov, B. G.

We present the color dipole phenomenology of diffractive photo- and electroproduction $\gamma^{*} N\to V(V') N$ of vector mesons ($V(1S) = \phi^0, \omega^0, \rho^0, J/\Psi, \Upsilon$) and their...

Color Dipole Systematics of Diffractive Photo- and Electroproduction of Vector Mesons (1996)

Nemchik, J., Nikolaev, N. N., Predazzi, E., Zakharov, B. G.

We present the first evaluation of color dipole cross section from experimental data on diffractive photo- and electroproduction of vector mesons. The dipole-size and energy dependence of the found...

Excitation of open charm and factorization breaking in rapidity gap events at HERA (1996)

Factorization properties of the diffraction dissociation of longitudinal photons (1996)

We develop the pQCD description of diffraction excitation of heavy flavours in DIS and we derive the analytic formulas for the mass spectrum in leading log$m_f^{2}$. The result illustrates nicely...

How to measure the pion structure function at HERA (1996)

We develop the pQCD description of the diffraction dissociation (DD) of longitudinal photons. We demonstrate that the longitudinal diffractive structure function does not factor into the flux of...

Holtmann, H., Levman, G., Nikolaev, N. N., Szczurek, A., Speth, J.

We suggest a method of determination of the pion structure function down to x \simeq 10^{-4} based on semi-exclusive deep inelastic scattering off protons. The idea is to exploit the nonperturbative...

Factorization properties of the diffraction dissociation of longitudinal photons (1996)

Genovese, M., Nikolaev, N.N., Zakharov, B.G.

We develop the pQCD description of the diffraction dissociation (DD) of longitudinal photons. We demonstrate that the longitudinal diffractive structure function does not factor into the Aux of...

Factorization properties of the diffraction dissociation of longitudinal photons (1996)

Genovese, M., Nikolaev, N.N., Zakharov, B.G.

We develop the pQCD description of the diffraction dissociation (DD) of longitudinal photons. We demonstrate that the longitudinal diffractive structure function does not factor into the Aux of...

Factorization properties of the diffraction dissociation of longitudinal photons (1996)

Genovese, M., Nikolaev, N.N., Zakharov, B.G.

We develop the pQCD description of the diffraction dissociation (DD) of longitudinal photons. We demonstrate that the longitudinal diffractive structure function does not factor into the Aux of...

Inclusive Heavy-Flavor Production from Nuclei (1995)

Nikolaev, N. N., Piller, G., Zakharov, B. G.

We describe a light-cone wave function formulation for hadroproduction of heavy-flavors at high energies. At moderate values of $x_F$ heavy-flavor production can be viewed as a diffractive excitation...

Color Transparency (1995)

Universal pattern in (e,e'p) at large missing momenta: quasi-deuteron or diffractive final state interactions? (1995)

The current status of the theory of and the experimental evidence for color transparency are reviewed. The problems with interpretation of quasielastic scattering on nuclei are discussed to some...

Bianconi, A., Jeschonnek, S., Nikolaev, N. N., Zakharov, B. G.

The intrinsic single particle momentum distributions in nuclei are supposed to show a universal behavior at large momenta, dominated by short-range correlated pairs, or quasi-deuterons. We discuss...

Do final state interactions obscure short range correlation effects in quasielastic $A(e,e'p)$ scattering? (1995)

Bianconi, A., Jeschonnek, S., Nikolaev, N. N., Zakharov, B. G.

Are short range correlations in the ground state of the target nucleus (initial state correlations ISC)observable inexperiments on quasielastic $A(e,e'p)$ scattering at large missing momentum...

Final state interactions and $NN$ correlations: are the latter observable? (1995)

Bianconi, A., Jeschonnek, S., Nikolaev, N. N., Speth, J., Zakharov, B. G.

Are effects of short range correlations in the ground state of the target nucleus (initial state correlations ISC) observable in experiments on quasielastic $A(e,e'p)$ scattering at large missing...

Exploratory study of shrinkage of the diffraction cone for the generalized BFKL pomeron (1995)

The strange quark distribution (1995)

In color dipole gBFKL dynamics, we describe the emerging gBFKL phenomenology of a subasymptotic energy dependence of the diffraction slope and discuss possibilities of testing the gBFKL predictions...

Barone, V, Genovèse, M, Nikolaev, N N, Predazzi, Enrico, Zakharov, B G

We discuss the latest CCFR determination of the strange sea density of the proton. We comment on the differences with a previous, leading--order, result and point out the relevance of quark mass...

THE STRANGE QUARK DISTRIBUTION (1995)

BARONE, V., GENOVESE, M., NIKOLAEV, N. N., PREDAZZI, E., ZAKHAROV, B. G.

We discuss the latest CCFR determination of the strange sea density of the proton. We comment on the differences with a previous, leading--order, result and point out the relevance of quark mass...

The longitudinal asymmetry of the $(e,e'p)$ missing momentum distribution as a signal of color transparency (1995)

Benhar, O., Fantoni, S., Nikolaev, N. N., Speth, J., Usmani, A. A., Zakharov, B. G.

We use multiple scattering theory to evaluate the $Q^{2}$ dependence of the forward-backward asymmetry, $A_{z}$, of the missing momentum distribution in quasielstic $A(e,e'p)$ scattering, which is...

On the determination of double diffraction dissociation cross section at HERA (1995)

Holtmann, H., Nikolaev, N. N., Szczurek, A., Speth, J., Zakharov, B. G.

The excitation of the proton into undetected multiparticle states (double diffraction dissociation) is an important background to single diffractive deep-inelastic processes $ep \rightarrow...

Glauber theory of final-state interactions in $(e,e'p)$ scattering (1995)

Nikolaev, N. N., Speth, J., Zakharov, B. G.

We develop the Glauber theory description of final-state interaction (FSI) in quasielastic $A(e,e'p)$ scattering. The important new effect is an interaction between the two trajectories which enter...

Quadrupole deformation of deuterons and final state interaction in $^2 \vec H (e,e'p)$ scattering on tensor polarized deuterons at CEBAF energies (1995)

Bianconi, A., Jeschonnek, S., Nikolaev, N. N., Zakharov, B. G.

The strength of final state interaction (FSI) between struck proton and spectator neutron in $^2\vec{H}(e,e'p)$ scattering depends on the alignment of the deuteron. We study the resulting FSI effects...

The longitudinal asymmetry of the (e,e'p) missing momentum distribution as a signal of color transparency (1995)

Benhar, Omar, Fantoni, Stefano, Nikolaev, N. N., Speth, J., Usmani, A. A.

The longitudinal asymmetry of the (e,e'p) missing momentum distribution as a signal of color transparency (1995)

Fantoni, Stefano, Benhar, Omar, Nikolaev, N. N., Speth, J., Usmani, A. A.

On the missing momentum dependence of the color transparency effects in (e,e'p) scattering (1995)

Benhar, Omar, Fantoni, Stefano, Nikolaev, N. N., Speth, J., Usmani, A. A., Zakharov, B. G.

Glauber theory of initial and final-state interactions in (p,2p) scattering (1995)

Benhar, Omar, Fantoni, Stefano, Usmani, A. A., Nikolaev, N. N., Speth, J., Zakharov, B. G.

Quantum coherence in heavy-flavor production on nuclei (1994)

Nikolaev, N. N., Piller, G., Zakharov, B. G.

We describe a light-cone wave function formalism for hadroproduction of heavy-flavors via gluon-gluon fusion. The developed approach is well suited to address coherence effects in heavy-quark...

Nuclear effects in the diffractive electroproduction of s$\overline{s}$ mesons (1994)

Benhar, O, Zakharov, B G, Nikolaev, N N, Fantoni, S

The direct calculation of the slope of the QCD pomeron's trajectory (1994)

The apparent Coulomb reacceleration of neutrons in electrodissociation of the deuteron (1994)

We demonstrate that the diffraction slope of the generalized BFKL pomeron amplitude has the conventional Regge growth $B(s) = B(0) + 2\alpha_{\Pom}'\log(s)$. This proves that the generalized BFKL...

Bianconi, A., Jeschonnek, S., Nikolaev, N. N., Zakharov, B. G.

We demonstrate that the final state $p$-$n$ interaction in the reaction of electrodissociation of the deuteron at large $Q^{2}$ in a static external field leads to the apparent reacceleration of...

Direct calculation of the triple-pomeron coupling for diffractive DIS and real photoproduction (1994)

Genovèse, M, Nikolaev, N N, Zakharov, B G

We present a unified direct calculation of the triple-pomeron coupling A_{3\Pom}(Q^{2}) for diffractive real photoproduction (Q^{2}=0) and deep inelastic scattering at large Q^{2} in the framework of...

Diffractive DIS from the generalized BFKL pomeron: predictions for HERA (1994)

Genovèse, M, Nikolaev, N N, Zakharov, B G

We present microscopic QCD calculation of the cross section of diffractive DIS and of the partonic structure of the pomeron from the dipole approach to the generalized BFKL pomeron. We show that the...

Direct calculation of the triple-pomeron coupling for diffractive DIS and real photoproduction (1994)

Diffractive DIS from the generalized BFKL pomeron. Predictions for HERA (1994)

We present a unified direct calculation of the triple-pomeron coupling $A_{3\Pom}(Q^{2})$ for diffractive real photoproduction ($Q^{2}=0$) and deep inelastic scattering at large $Q^{2}$ in the...

How to measure the pion structure function at HERA (1994)

We present microscopic QCD calculation of the cross section of diffractive DIS and of the partonic structure of the pomeron from the dipole approach to the generalized BFKL pomeron. We show that the...

Holtmann, H, Levman, G, Nikolaev, N N, Szczurek, A, Speth, J

Theoretical interpretation of the NE18 experiment on nuclear transparency in A(e,e'p) scattering (1994)

Nikolaev, N N, Szczurek, A, Speth, J, Wambach, J, Zakharov, B G, Zoller, V R

The spectral function, measured in $A(e,e'p)$ reactions, is distorted by the final-state interaction of the struck proton with the residual nucleus. This causes a broadening of the observed...

Final state interaction effects in $D(e,e'p)$ scattering (1994)

Bianconi, A., Jeschonnek, S., Nikolaev, N. N., Zakharov, B. G.

We present a systematic study of the final-state interaction (FSI) effects in $D(e,e'p)$ scattering in the CEBAF energy range with particular emphasis on the phenomenon of the angular anisotropy of...

Simple classification of final state interaction effects in $^4He(e,e'p)$ scattering (1994)

Bianconi, A., Jeschonnek, S., Nikolaev, N. N., Zakharov, B. G.

The radius of interaction between the struck proton and spectator nucleons is close to the radius of short-distance two-nucleon correlations in nuclear matter, which makes final state...

Color transparency after the NE18 and E665 experiments: Outllok and perspectives at CEBAF (1994)

Nemchik, J., Nikolaev, N. N., Zakharov, B. G.

CEBAF is a high-luminocity factory of virtual photons with variable virtuality $Q^{2}$ and transverse size. This makes CEBAF, in particular after the energy upgrade to (8-12)GeV, an ideal facility...

Why more hadronlike photons produce less particles on nuclear targets (1994)

Scanning the BFKL pomeron in elastic production of vector mesons at HERA (1994)

In hadron-nucleus interactions, the stronger is nuclear shadowing in the total cross section the higher is the multiplicity of secondary hadrons. In deep inelastic scattering, nuclear shadowing at...

Nemchik, J., Nikolaev, N. N., Zakharov, B. G.

Elastic production of vector mesons $\gamma^{*} N\to V N$ is the pomeron-exchange dominated diffractive reaction with much potential of probing the BFKL pomeron. The BFKL pomeron can conveniently be...

Anomalous A-dependence of diffractive leptoproduction of radial excitation $\rho'(2S)$ (1994)

Nemchik, J., Nikolaev, N. N., Zakharov, B. G.

We predict a strikingly different $A$ and $Q^{2}$ dependence of quasielastic leptoproduction of the $\rho^{0}(1S)$-meson and its radial excitation $\rho '(2S)$ on nuclei. Whereas for the $\rho^{0}$...

Pion Content of the Nucleon as seen in the NA51 Drell-Yan experiment (1994)

Holtmann, H., Nikolaev, N. N., Speth, J., Szczurek, A.

In a recent CERN Drell-Yan experiment the NA51 group found a strong asymmetry of $\bar u$ and $\bar d$ densities in the proton at $x\simeq0.18$. We interpret this result as a decisive confirmation of...

Splitting the pomeron into two jets: a novel process at HERA (1994)

How to measure the intercept of the BFKL pomeron at HERA (1994)

We study a novel property of large rapidity-gap events in deep inelastic scattering at HERA: splitting the pomeron into two jets in the photon-pomeron fusion reaction $\gamma^{*}\Pom \rightarrow...

On determination of the large-${1\over x}$ gluon distribution at HERA (1994)

Determination of the intercept of the BFKL pomeron is one of the pressing issues in the high energy physics. Earlier we have shown that, at the dipole size $r=r_{\Delta}=(0.1-0.2)$f, the dipole cross...

Leptoproduction of charm revisited (1994)

We discuss corrections to the Leading-Log$Q^{2}$ relationships between the gluon density $g(x,Q^{2})$ and $F_{L}(x,Q^{2}),\,\partial F_{T}(x,Q^{2}) /\partial \log Q^{2}$ in the HERA range of large...

Barone, V., Genovese, M., Nikolaev, N. N., Predazzi, E., Zakharov, B. G.

We calculate the energy--momentum distribution of the charmed quarks produced in neutrino reactions on protons, quantifying the importance of mass and current non--conservation effects. We study the...

The BFKL and GLDAP regimes for the perturbative QCD pomeron (1994)

Theoretical Interpretation of the NE18 Experiment on Nuclear Transparency in A(e,e'p) Scattering (1994)

The $S$-matrix of diffractive scattering is diagonalized in terms of the colour dipole-dipole cross section. Recently, we have shown that the dipole cross section satisfies the generalized BFKL...

Nikolaev, N. N., Szczurek, A., Speth, J., Wambach, J., Zakharov, B. G., Zoller, V. R.

The spectral function, measured in $A(e,e'p)$ reactions, is distorted by the final-state interaction of the struck proton with the residual nucleus. This causes a broadening of the observed...

Deep inelastic scattering at HERA and the BFKL pomeron (1994)

BFKL evolution and universal structure function at very small $x$ (1994)

We present a BFKL phenomenology of structure functions in the framework of the generalized BFKL equation for the dipole cross section proposed by us recently. We show that the HERA measurements of...

The spectrum and solutions of the generalized BFKL equation for total cross section (1994)

The Balitskii-Fadin-Kuraev-Lipatov (BFKL) and the Gribov-Lipatov- Dokshitzer-Altarelli-Parisi (GLDAP) evolution equations for the diffractive deep inelastic scattering at ${1\over x} \gg 1$ are shown...

The $s$-channel approach to Lipatov's pomeron and hadronic cross sections (1993)

The colour dipole cross section is the principal quantity in the lightcone $s$-channel description of the diffractive scattering. Recently we have shown that the dipole cross section satisfies the...

Decisive test of color transparency in exclusive electroproduction of vector mesons (1993)

We derive a generalized Balitskii-Fadin-Kuraev-Lipatov equation, which applies directly to the perturbative QCD component of total cross section. With the gluon correlation radius $R_{c} \sim 0.4$f...

Kopeliovich, B. Z., Nemchick, J., Nikolaev, N. N., Zakharov, B. G.

The exclusive production of vector mesons in deep inelastic scattering is a hard scattering process with the well controlled size of quark configurations which dominate the production amplitude. This...

Color Transparency after the Ne18 and E665 Experiments (1993)

Shadowing in deuterium and the small--$x$ limit of $F_2^n/F_2^p$ and $F_2^p - F_2^n$ (1993)

The 1993 witnessed two major news in the field of color transparency (CT): i) no effect of CT was seen in the SLAC NE18 experiment on $A(e,e'p)$ scattering at virtualities of the exchanged photon...

Barone, V., Genovese, M., Nikolaev, N. N., Predazzi, E., Zakharov, B. G.

We discuss the updated NMC determination of $F_2^n/F_2^p$ and $F_2^p - F_2^n$. Shadowing effects in deuterium make the structure functions determined by the NMC sensibly different from the true ones...

Non universality of structure functions and measurement of the strange sea density (1993)

Barone, V., Genovese, M., Nikolaev, N. N., Predazzi, E., Zakharov, B. G.

We show that there is no real conflict between the two determinations of the strange sea density from the opposite--sign dimuon production and from the difference of the $F_2$ structure functions...

Unitarization of Structure Functions at Large ${\bf 1/x}$ (1993)

Barone, V., Genovese, M., Nikolaev, N. N., Predazzi, E., Zakharov, B. G.

We discuss the effects of the $s$-channel unitarization on the $x$ and $Q^{2}$ dependence of structure functions. The unitarization is implemented at the level of photoabsorption cross sections by...

Correlation Effects in the Final-State Interaction for Quasielastic $(e,e'p)$ Scattering (1993)

Nikolaev, N. N., Szczurek, A., Speth, J., Wambach, J., Zakharov, B. G., Zoller, V. R.

Color transparency predicts that, in $(e,e'p)$ reactions at large $Q^2$, the final-state interaction becomes weaker than the reference value predicted from the free-nucleon cross section. This...

The triple-pomeron regime and the structure function of the pomeron in the diffractive deep inelastic scattering at very small x (1993)

Novel Color Transparency Effect: Scanning the Wave Function of Vector Mesons (1993)

Misprints and numerical coefficients corrected, a bit of phenomenology and one figure added. The case for the linear evolution of the unitarized structure functions made stronger.

Kopeliovich, B. Z., Nemchick, J., Nikolaev, N. N., Zakharov, B. G.

We demonstrate how the virtual photoproduction of vector mesons on nuclei scans the wave function of vector mesons from the large non-perturbative transverse size $\rho \sim R_{V}$ down to the small...

Asymptotic behaviour of the total cross section of p-p scattering and the Akeno cosmic ray data (1993)

Colour transparency: a novel test of QCD in nuclear interactions (1993)

I present a new determination of the total cross section for proton-proton collisions from the recent Akeno results on absorption of the cosmic ray protons in the p-Air collisions. Extrapolation to...