Related papers: Nuclear phenomena at HERA energies
We studied a left-right symmetric model that can accommodate the neutrino dark energy (\nd) proposal. Type III seesaw mechanism is implemented to give masses to the neutrinos. After explaining the model, we study the consistency of the…
The planed HERA upgrade will increase the integrated luminosity by two orders of magnitude.A new program of electron-nucleus collisions at HERA is under discussion now.In this connection we present prospects for the study of a light neutral…
Recent results from HERA are presented on a range of topics: charged multiplicities, production of non-strange mesons and strange particles, charm fragmentation, baryons decaying to strange particles, antideuteron production, Bose-Einstein…
The dilepton spectra from open charm decay in $p+A$ reactions at $\sqrt s=200$ AGeV are proposed to constrain gluon shadowing in nuclei. We show that the required measurements are feasible at RHIC.
A systematic multiple scattering formalism for vector meson electroproduction from nuclei is developed, with emphasis on the formation, propagation and hadronization scales for quark-gluon fluctuations of the virtual high-energy photon. The…
We calculate the shadowing of sea quarks and gluons and show that the shadowing of gluons is {\it not} simply given by the sea quark shadowing, especially at small $x$. The calculations are done in the lab frame approach by using the…
A study has been made of the physics interest and feasibility of experiments with nuclear beams in HERA. It is shown that such experiments widen considerably the horizon for probing QCD compared to that from free nucleon targets. In…
A model for shadowing in nuclear structure functions at small $x$ and small or moderate $Q^2$ is presented using the relation with diffraction that arises from Gribov's reggeon calculus. A reasonable description of the experimental data is…
We study how factorization breaking changes when going from diffractive deep inelastic scattering to diffractive photoproduction of dijets. These processes offer a sensitive probe of the interplay of soft and hard mechanisms in QCD. We…
So far no theoretical tool for the comprehensive description of exclusive electroproduction of vector mesons off nuclei at medium energies has been developed. We suggest a light-cone QCD formalism which is valid at any energy and…
I review hard photon initiated processes on nuclei. The space-time development of the DIS reaction as viewed in the target rest frame qualitatively describes the nuclear shadowing of quark and gluon distributions, although it may be…
Present limits on neutrino masses are briefly reviewed, along with cosmological and astrophysical hints from dark matter, solar and atmospheric neutrino observations that suggest neutrino masses. These would imply many possible new…
We study nuclear shadowing at small Bjorken x < 0.01 in the color dipole approach. Such a light-cone quantum-chromodynamics formalism based on the Green function technique incorporates naturally color transparency and coherence length…
A selection of results from the H1 and ZEUS experiments at HERA are reviewed, particularly in the area of deep inelastic scattering and diffraction. Quantum chromodynamics gives a good explanation of these data down to surprisingly low…
The early onset of nuclear shadowing in photoabsorption at low photon energies has recently been interpreted as a possible signature of a decrease of the rho meson mass in nuclei. We show that one can understand this early onset within…
We re-examine the role of vector meson dominance in nuclear shadowing at low Q^2. We find that models which incorporate both vector meson and partonic mechanisms are consistent with both the magnitude and the Q^2 slope of the shadowing…
Motivated by the recent results for DIS off nuclei from the HERMES experiment we have performed a systematic study of shadowing for transverse and longitudinal photons. We found that the coherence length which controls the onset of nuclear…
The coherence of multiscattering quark nuclear processes leads to shadowing and antishadowing of the electromagnetic nuclear structure functions in agreement with measurements. This picture leads to substantially different antishadowing for…
We study the implications of non-universality observed recently in e p and pbar p diffraction for nuclear shadowing and diffractive dijet production in pA collisions.
The most important results on subnuclear diffractive phenomena obtained at HERA and Tevtaron are reviewed and new issues in nucleon tomography are discussed. Some challenges for understanding diffraction at the LHC, including the…