Gamma-Jet Tomography of Quark-Gluon Plasma in High-Energy Nuclear Collisions

Within the next-to-leading order (NLO) perturbative QCD (pQCD) parton model, suppression of away-side hadron spectra associated with a high $p_{T}$ photon due to parton energy loss is shown to provide a complete tomographic picture of the dense matter formed in high-energy heavy-ion collisions at RHIC. Dictated by the shape of the $\gamma$-triggered jet spectrum in NLO pQCD, hadron spectra at large $z_T=p_T^{h}/p_T^{\gamma} \stackrel{>}{\sim} 1$ are more susceptible to parton energy loss and therefore are dominated by surface emission of $\gamma$-triggered jets, whereas small $z_{T}$ hadrons mainly come from fragmentation of jets with reduced energy from volume emission. These lead to different centrality dependence of the hadron suppression in different regions of $z_{T}$.Comment: 4 pages, 3 figures, proceedings for QM 2009 conferenc

A systematic account of the genus Plagiostoma (Gnomoniaceae, Diaporthales) based on morphology, host-associations, and a four-gene phylogeny

Members of the genus Plagiostoma inhabit leaves, stems, twigs, and branches of woody and herbaceous plants predominantly in the temperate Northern Hemisphere. An account of all known species of Plagiostoma including Cryptodiaporthe is presented based on analyses of morphological, cultural, and DNA sequence data. Multigene phylogenetic analyses of DNA sequences from four genes (β-tubulin, ITS, rpb2, and tef1-α) revealed eight previously undescribed phylogenetic species and an association between a clade composed of 11 species of Plagiostoma and the host family Salicaceae. In this paper these eight new species of Plagiostoma are described, four species are redescribed, and four new combinations are proposed. A key to the 25 accepted species of Plagiostoma based on host, shape, and size of perithecia, perithecial arrangement in the host, and microscopic characteristics of the asci and ascospores is provided. Disposition of additional names in Cryptodiaporthe and Plagiostoma is also discussed