Strange and Multi-Strange Particle Production in P+P Collisions at s\sqrt{s}=200 Gev in Star

We present measurements of the transverse momentum spectra for K0s, Lambda, Xi and their antiparticles in p+p collisions at $\sqrt{s}=200$ GeV. The extracted mid-rapidity yields and are in agreement with previous $p+\bar{p}$ experiments while they have smaller statistical errors. We compare the measured particle spectra and values to predictions from the PYTHIA leading order pQCD model (v6.221) and see significant disagreements with the default settings. Finally we compare the spectra to the latest calculations from NLO pQCD and see a good agreement for the K0s, but large discrepancies Lambda.Comment: 4 pages, Proceedings for the 40th Rencontres de Moriond (QCD), La Thuile, March 200

Heavy flavor measurements using high-pt electrons in the ALICE EMCal

Heavy flavor hadrons, i.e. those containing charm and bottom quarks, will be abundantly produced at the LHC and are important probes of the Quark-Gluon Plasma (QGP). Of particular interest is the investigation of parton energy loss in the medium. Using heavy flavor jets we will have a pure sample of quark jets with which to study the color-charge effects on energy loss. In addition, studies of bottom production in p+p collision at LHC energies will be utilized to further constrain the current parameters used by NLO and FONLL calculations. The talk will focus on the very high-pt electron particle identification using the EMCal detector. We present the electron reconstruction and measurements which can be achieved with 1 nominal year of Pb-Pb running at 5.5 TeV. We then estimate the rate of non-photonic electrons and present systematic and statistical error bars. Finally, we show preliminary results on B-jet tagging techniques in p+p which utilize jet-finding algorithms (FASTJET) in conjunction with displaced secondary vertices containing high-pt electrons.Comment: 9 pages, proceedings for the 26th Winter Workshop on Nuclear Dynamics, Ocho Rios Jamaica, Jan 2-9, 201

Reconstructing Bottom mesons using displaced vertices from semi-leptonic decays

Precise determination of heavy flavor production cross-sections at LHC energies will be of primary importance. The produced heavy quarks are expected to be sensitive probes of parton energy loss in the medium formed in heavy-ion collisions. Through the measurement of charm and bottom suppression in Pb + Pb with respect to p + p, we hope to obtain insight into the color-charge and quark mass dependence of the energy loss mechanism. The ALICE experiment with its large acceptance is well suited to investigate the intermediate transverse momentum spectrum of heavy flavor mesons where these energy loss effects are expected to be visible. ALICE has very good electron PID capabilities over a large kinematic range using Time Projection Chamber (TPC), Transition Radiation Detector (TRD) and the Electromagnetic Calorimeter (EMCal). In addition the EMCal, to be installed for the Pb + Pb runs, is planned to allow efficient triggering on high-pT jets. We first introduce the EMCal project and an overview of detector specifications. Then we introduce a method developed to select preferentially electrons from heavy flavor decays by reconstructing displaced secondary vertices. The strategy is to reconstruct displaced vertices from semi-leptonic heavy flavor meson decays using the excellent spatial resolution of the Inner Tracking System (ITS). We show preliminary results of an efficiency study from charm vs. bottom vertices.Comment: 8 pages, Proceedings of Winter Workshop of Nuclear Dynamics 2007, Big Sky, M

Pion chemical equilibration in heavy ion collisions : relativistic quantum molecular dynamic analysis

In the framework of relativistic quantum molecular dynamics the authors find that the pion system produced in central heavy-ion collisions at Elab/A approximately 1 GeV/nucl. is out of chemical equilibrium. Pion chemical potential is large and decreases during the expansion stage

Radial flow afterburner for event generators and the baryon puzzle

A simple afterburner including radial flow to the randomized transverse momentum obtained from event generators, Pythia and Hijing, has been implemented to calculate the $p/\pi$ ratios and compare them with available data. A coherent trend of qualitative agreement has been obtained in $pp$ collisions and in $Au+Au$ for various centralities. Those results indicate that the radial flow does play an important role in the so called baryon puzzle anomaly.Comment: 11 pages, 5 figures. To appear in Journal of Physics

Subarachnoid Hemorrhage from Posterior Cerebral Artery Aneurysm during Puerperium – Case Report and Review of Literature

Subarachnoid hemorrhages (SAH) due to true aneurysms of the Posterior Cerebral Artery (PCA) during puerperium in young and healthy females are extremely rare. We present the case of a 31-year old, healthy woman that experienced a spontaneous SAH due to a PCA aneurysm, arising from the P3 segment, 9 days post-delivery. The aneurysm was successfully treated via an endovascular approach and the patient recovered well. After 21 days she was discharged from hospital without neurological deficits. The clinical course is described in detail and illustrated with a computed tomography scan (CT) and digital subtraction angiography (DSA) pre – and post-embolization. The literature is reviewed and possible etiologies of the formation and rupture of the aneurysm are discussed