Structure Functions of Nuclei at Small x and Diffraction at HERA

Gribov theory is applied to investigate the shadowing effects in the structure functions of nuclei. In this approach these effects are related to the process of diffractive dissociation of a virtual photon. A model for this diffractive process, which describes well the HERA data, is used to calculate the shadowing in nuclear structure functions. A reasonable description of the x, Q^2 and A-dependence of nuclear shadowing is achieved.Comment: TeX, 10 pages, 7 figures in 6 ps-file

Hard Diffraction at HERA and the Gluonic Content of the Pomeron

We show that the previously introduced CKMT model, based on conventional Regge theory, gives a good description of the HERA data on the structure function F_2^D for large rapidity gap (diffractive) events. These data allow, not only to determine the valence and sea quark content of the Pomeron, but also, through their Q^2 dependence, give information on its gluonic content. Using DGLAP evolution, we find that the gluon distribution in the Pomeron is very hard and the gluons carry more momentum than the quarks. This indicates that the Pomeron, unlike ordinary hadrons, is a mostly gluonic object. With our definition of the Pomeron flux factor the total momentum carried by quarks and gluons turns out to be 0.3-0.4 - strongly violating the momentum sum rule.Comment: C-Shell archive of a PostScript file containing a 20 page paper with text and 12 figures in i

Strange Baryon Production in Heavy Ion Collisions

The rapidity distribution of $\Lambda$ and $\bar{\Lambda}$ produced in nucleus-nucleus collisions at CERN energies is studied in the framework of an independent string model - with quark-antiquark as well as diquark-antidiquark pairs in the nucleon sea. It is shown that, besides the $\Lambda$-$\bar{\Lambda}$ pair production resulting from the fragmentation of sea diquarks, final state interactions of co-moving secondaries $\pi + N \to K + \Lambda$ and $\pi + \bar{N} \to K + \bar{\Lambda}$ are needed in order to reproduce the data. Predictions for $Pb$-$Pb$ collisions are presented.Comment: Plain TeX + epsf, 40 pages; 1 Postscript-table and 7 Postscript figures (uuencoded

Diffractive Dissociation in Deep Inelastic Scattering at HERA

The diffraction dissociation of virtual photons is considered in the framework of conventional Regge theory. It is shown that the recent HERA data on large rapidity gap events can be successfully described in terms of the Pomeron structure function. Using Regge factorization, the latter can be related to the deuteron structure function. The parameters which relate these two structure functions are determined from soft hadronic diffraction data. The size of the shadowing corrections at low x and large Q**2 is also obtained.Comment: 17 pages, TEX, preprint LPTHE Orsay 94-4

Production Associated to Rare Events in High Energy Hadron-Hadron Collisions

At very high energy the same universal relation between the multiparticle or the transverse energy distribution associated to a rare event $C$, $P_C$ and the corresponding minimum bias distribution P, $P_C(\nu)\equiv \nu/ P(\nu)$, $\nu\equiv n$ or $E_T$ works for nucleus-nucleus collisions as well as for hadron-hadron collisions. This suggests that asymptotically, all hadronic processes are similar.Comment: 9 pages, 4 Postscript figure

Solar models and solar neutrino oscillations

We provide a summary of the current knowledge, theoretical and experimental, of solar neutrino fluxes and of the masses and mixing angles that characterize solar neutrino oscillations. We also summarize the principal reasons for doing new solar neutrino experiments and what we think may be learned from the future measurements.Comment: Submitted to the Neutrino Focus Issue of New Journal of Physics at http://www.njp.or

WHOI Hawaii Ocean Timeseries Station (WHOTS): WHOTS-11 2014 mooring Turnaround Cruise Report

The Woods Hole Oceanographic Institution (WHOI) Hawaii Ocean Timeseries Site (WHOTS), 100 km north of Oahu, Hawaii, is intended to provide long-term, high-quality air-sea fluxes as a part of the NOAA Climate Observation Program. The WHOTS mooring also serves as a coordinated part of the Hawaii Ocean Timeseries (HOT) program, contributing to the goals of observing heat, fresh water and chemical fluxes at a site representative of the oligotrophic North Pacific Ocean. The approach is to maintain a surface mooring outfitted for meteorological and oceanographic measurements at a site near 22.75°N, 158°W by successive mooring turnarounds. These observations will be used to investigate air–sea interaction processes related to climate variability. This report documents recovery of the tenth WHOTS mooring (WHOTS-10) and deployment of the eleventh mooring (WHOTS-11). Both moorings used Surlyn foam buoys as the surface element and were outfitted with two Air–Sea Interaction Meteorology (ASIMET) systems. Each ASIMET system measures, records, and transmits via Argos satellite the surface meteorological variables necessary to compute air–sea fluxes of heat, moisture and momentum. The upper 155 m of the moorings were outfitted with oceanographic sensors for the measurement of temperature, conductivity and velocity in a cooperative effort with R. Lukas of the University of Hawaii. A pCO2 system and ancillary sensors were installed on the buoys in cooperation with Chris Sabine at the Pacific Marine Environmental Laboratory. A set of radiometers were installed in cooperation with Sam Laney at WHOI. The WHOTS mooring turnaround was done on the NOAA ship Hi’ialakai by the Upper Ocean Processes Group of the Woods Hole Oceanographic Institution. The cruise took place between 15 and 23 July 2014. Operations began with deployment of the WHOTS-11 mooring on 16 July. This was followed by meteorological intercomparisons and CTDs. Recovery of the WHOTS-10 mooring took place on 20 July. This report describes these cruise operations, as well as some of the in-port operations and pre-cruise buoy preparations.Funding was provided by the National Oceanic and Atmospheric Administration under Grant No. NA140AR4320158 and the Cooperative Institute for the North Atlantic Region (CINAR