Foliations with few non-compact leaves

Let F be a foliation of codimension 2 on a compact manifold with at least one non-compact leaf. We show that then F must contain uncountably many non-compact leaves. We prove the same statement for oriented p-dimensional foliations of arbitrary codimension if there exists a closed p form which evaluates positively on every compact leaf. For foliations of codimension 1 on compact manifolds it is known that the union of all non-compact leaves is an open set [A Haefliger, Varietes feuilletes, Ann. Scuola Norm. Sup. Pisa 16 (1962) 367-397].Comment: Published by Algebraic and Geometric Topology at http://www.maths.warwick.ac.uk/agt/AGTVol2/agt-2-12.abs.htm

Baseline Cold Matter Effects on J/psi Production in AA Collisions

We present baseline calculations of initial-state shadowing and final-state absorption effects on J/psi production in nucleus-nucleus collisions at the Relativistic Heavy Ion Collider. We show predictions for Au+Au and Cu+Cu collisions at \sqrt{S_{NN}}=200 GeV and Cu+Cu collisions at \sqrt{S_{NN}} = 62 GeV as a function of the rapidity, y, and the number of binary nucleon-nucleon collisions, N_{\rm coll}.Comment: 7 pages, 4 figures, uses hiph-art.sty, one figure replaced, some corrections to tex

Open and Hidden Charm Production in dAA Collisions at RHIC and LHC

We discuss aspects of open and hidden charm production in deuterium-nucleus collisions at RHIC and LHC energies. We describe calculations of the total $c \bar c$ cross section and the charm quark transverse momentum distributions. We next explain how shadowing and moderate nuclear absorption can explain the PHENIX $J/\psi$ dAu/$pp$ ratios and predict the combined effect of shadowing and absorption in 6.2 TeV d+Pb collisions.Comment: 6 pages, 4 figures, European Physics Journal conference proceedings style files included, in proceedings of Hard Probes, 2004 Ericeira, Portuga

Systematics of Heavy Quark Production at RHIC

We discuss a program for systematic studies of heavy quark production in $pp$, $pA$ and $AA$ interactions. The $Q \bar Q$ production cross sections themselves cannot be accurately predicted to better than 50% at RHIC. For studies of deviations in $Q \bar Q$ production such as those by nuclear shadowing and heavy quark energy loss, the $pp$ cross section thus needs to be measured. We then show that the ratio of $pA$ to $pp$ dilepton mass distributions can provide a measurement of the nuclear gluon distribution. With total rates and nuclear shadowing under control it is easier to study energy loss and to use $c \bar c$ as a normalization of $J/\psi$ production.Comment: 10 pages, uses special included style file, 4 eps figures, for proceedings of the 18th Winter Workshop on Nuclear Dynamics, Jan. 200

Are We All Scientific Experts Now

Book review of Harry Collins book 'Are we all scientific experts now?