Suppression of charged particle production at large transverse momentum in central Pb-Pb collisions at sNN=2.76\sqrt{s_{\rm NN}} = 2.76 TeV

Inclusive transverse momentum spectra of primary charged particles in Pb-Pb collisions at $\sqrt{s_{_{\rm NN}}}$ = 2.76 TeV have been measured by the ALICE Collaboration at the LHC. The data are presented for central and peripheral collisions, corresponding to 0-5% and 70-80% of the hadronic Pb-Pb cross section. The measured charged particle spectra in $|\eta|<0.8$ and $0.3 < p_T < 20$ GeV/$c$ are compared to the expectation in pp collisions at the same $\sqrt{s_{\rm NN}}$, scaled by the number of underlying nucleon-nucleon collisions. The comparison is expressed in terms of the nuclear modification factor $R_{\rm AA}$. The result indicates only weak medium effects ($R_{\rm AA} \approx$ 0.7) in peripheral collisions. In central collisions, $R_{\rm AA}$ reaches a minimum of about 0.14 at $p_{\rm T}=6$-7GeV/$c$ and increases significantly at larger $p_{\rm T}$. The measured suppression of high-$p_{\rm T}$ particles is stronger than that observed at lower collision energies, indicating that a very dense medium is formed in central Pb-Pb collisions at the LHC.Comment: 15 pages, 5 captioned figures, 3 tables, authors from page 10, published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/98

Two-pion Bose-Einstein correlations in central Pb-Pb collisions at sNN\sqrt{s_{\rm NN}} = 2.76 TeV

The first measurement of two-pion Bose-Einstein correlations in central Pb-Pb collisions at $\sqrt{s_{\rm NN}} = 2.76$ TeV at the Large Hadron Collider is presented. We observe a growing trend with energy now not only for the longitudinal and the outward but also for the sideward pion source radius. The pion homogeneity volume and the decoupling time are significantly larger than those measured at RHIC.Comment: 17 pages, 5 captioned figures, 1 table, authors from page 12, published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/388

Transverse momentum spectra of charged particles in proton-proton collisions at s=900\sqrt{s} = 900 GeV with ALICE at the LHC

The inclusive charged particle transverse momentum distribution is measured in proton-proton collisions at $\sqrt{s} = 900$ GeV at the LHC using the ALICE detector. The measurement is performed in the central pseudorapidity region $(|\eta|<0.8)$ over the transverse momentum range $0.15<p_{\rm T}<10$ GeV/$c$. The correlation between transverse momentum and particle multiplicity is also studied. Results are presented for inelastic (INEL) and non-single-diffractive (NSD) events. The average transverse momentum for $|\eta|<0.8$ is $\left<p_{\rm T}\right>_{\rm INEL}=0.483\pm0.001$ (stat.) $\pm0.007$ (syst.) GeV/$c$ and \left_{\rm NSD}=0.489\pm0.001 (stat.) $\pm0.007$ (syst.) GeV/$c$, respectively. The data exhibit a slightly larger $\left<p_{\rm T}\right>$ than measurements in wider pseudorapidity intervals. The results are compared to simulations with the Monte Carlo event generators PYTHIA and PHOJET.Comment: 20 pages, 8 figures, 2 tables, published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/390

Candida rugosa, an Emerging Fungal Pathogen with Resistance to Azoles: Geographic and Temporal Trends from the ARTEMIS DISK Antifungal Surveillance Program

Candida rugosa is a fungus that appears to be emerging as a cause of infection in some geographic regions. We utilized the extensive database of the ARTEMIS DISK Antifungal Surveillance Program to describe the geographic and temporal trends in the isolation of C. rugosa from clinical specimens and the in vitro susceptibilities of 452 isolates to fluconazole and voriconazole. C. rugosa accounted for 0.4% of 134,715 isolates of Candida, and the frequency of isolation increased from 0.03% to 0.4% over the 6.5-year study period (1997 to 2003). C. rugosa was most common in the Latin American region (2.7% versus 0.1 to 0.4%). Decreased susceptibility to fluconazole (40.5% susceptible) was observed in all geographic regions; however, isolates from Europe and North America were much more susceptible (97 to 100%) to voriconazole than those from other geographic regions (55.8 to 58.8%). C. rugosa was most often isolated from blood and urine in patients hospitalized at the Medical and Surgical inpatient services. Notably, bloodstream isolates were the least susceptible to both fluconazole and voriconazole. C. rugosa should be considered, along with the established pathogens Candida krusei and Candida glabrata, as a species of Candida with reduced susceptibility to the azole antifungal agents

Elliptic flow of charged particles in Pb-Pb collisions at √s nn=2.76TeV

We report the first measurement of charged particle elliptic flow in Pb-Pb collisions at √sNN=2.76TeV with the ALICE detector at the CERN Large Hadron Collider. The measurement is performed in the central pseudorapidity region (|η|&amp;lt;0.8) and transverse momentum range 0.2&amp;lt;pt&amp;lt;5.0GeV/c. The elliptic flow signal v2, measured using the 4-particle correlation method, averaged over transverse momentum and pseudorapidity is 0.087±0.002(stat)±0.003(syst) in the 40%-50% centrality class. The differential elliptic flow v 2(pt) reaches a maximum of 0.2 near pt=3GeV/c. Compared to RHIC Au-Au collisions at √sNN=200GeV, the elliptic flow increases by about 30%. Some hydrodynamic model predictions which include viscous corrections are in agreement with the observed increase. © 2010 American Physical Society

Suppression of charged particle production at large transverse momentum in central Pb-Pb collisions at sNN=2.76 TeV

Inclusive transverse momentum spectra of primary charged particles in Pb-Pb collisions at sNN=2.76 TeV have been measured by the ALICE Collaboration at the LHC. The data are presented for central and peripheral collisions, corresponding to 0-5% and 70-80% of the hadronic Pb-Pb cross section. The measured charged particle spectra in |n|&lt;0.8 and 0.3&lt;pT&lt;20 GeV/c are compared to the expectation in pp collisions at the same sNN, scaled by the number of underlying nucleon-nucleon collisions. The comparison is expressed in terms of the nuclear modification factor RAA. The result indicates only weak medium effects (RAA≈0.7) in peripheral collisions. In central collisions, RAA reaches a minimum of about 0.14 at pT=6-7 GeV/c and increases significantly at larger pT. The measured suppression of high- pT particles is stronger than that observed at lower collision energies, indicating that a very dense medium is formed in central Pb-Pb collisions at the LHC. © 2010 CERN