Pion and Kaon Spectra from Distributed Mass Quark Matter

After discussing some hints for possible masses of quasiparticles in quark matter on the basis of lattice equation of state, we present pion and kaon transverse spectra obtained by recombining quarks with distributed mass and thermal cut power-law momenta as well as fragmenting by NLO pQCD with intrinsic $k_T$ {and nuclear} broadening.Comment: Talk given at SQM 200

Star Formation from Galaxies to Globules

The empirical laws of star formation suggest that galactic-scale gravity is involved, but they do not identify the actual triggering mechanisms for clusters in the final stages. Many other triggering processes satisfy the empirical laws too, including turbulence compression and expanding shell collapse. The self-similar nature of the gas and associated young stars suggests that turbulence is more directly involved, but the small scale morphology of gas around most embedded clusters does not look like a random turbulent flow. Most clusters look triggered by other nearby stars. Such a prominent local influence makes it difficult to understand the universality of the Kennicutt and Schmidt laws on galactic scales. A unified view of multi-scale star formation avoids most of these problems. Ambient self-gravity produces spiral arms and drives much of the turbulence that leads to self-similar structures, while localized energy input from existing clusters and field supernovae triggers new clusters in pre-existing clouds. The hierarchical structure in the gas made by turbulence ensures that the triggering time scales with size, giving the Schmidt law over a wide range of scales and the size-duration correlation for young star fields. The efficiency of star formation is determined by the fraction of the gas above a critical density of around 10^5 m(H2)/cc. Star formation is saturated to its largest possible value given the fractal nature of the interstellar medium.Comment: accepted for ApJ, 42 pages, Dannie Heineman prize lecture, January 200

How to Search for Doubly Charmed Baryons and Tetraquarks

Possible experimental searches of doubly charmed baryons and tetraquarks at fixed target experiments with high energy hadron beams and a high intensity spectrometer are considered here. The baryons considered are: $\Xi_{cc}^{+}$ (ccd), $\Xi_{cc}^{++}$ (ccu), and $\Omega_{cc}^{+}$ (ccs); and the tetraquark is T ($cc\bar{u}\bar{d}$). Estimates are given of masses, lifetimes, internal structure, production cross sections, decay modes, branching ratios, and yields. Experimental requirements are given for optimizing the signal and minimizing the backgrounds. The discussion is in the spirit of an experimental and theoretical review, as part of the planning for a CHarm Experiment with Omni-Purpose Setup (CHEOPS) at CERN. The CHEOPS objective is to achieve a state-of-the-art very charming experiment, in the spirit of the aims of the recent CHARM2000 workshop.Comment: 18 pages text (latex), 16 March 1995, presented at "Physics with Hadron Beams with a High Intensity Spectrometer", revised 10 May for more complete bibliography and appropriate references to S. Paul et al., Letter of Intent, CHEOPS