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The production rates and the transverse momentum distribution of strange hadrons at mid-rapidity ( [Formula omitted]) are measured in proton-proton collisions at [Formula omitted] = 13 TeV as a function of the charged particle multiplicity, using the ALICE detector at the LHC. The production rates of [Formula omitted], [Formula omitted], [Formula omitted], and [Formula omitted] increase with the multiplicity faster than what is reported for inclusive charged particles. The increase is found to be more pronounced for hadrons with a larger strangeness content. Possible auto-correlations between the charged particles and the strange hadrons are evaluated by measuring the event-activity with charged particle multiplicity estimators covering different pseudorapidity regions. When comparing to lower energy results, the yields of strange hadrons are found to depend only on the mid-rapidity charged particle multiplicity. Several features of the data are reproduced qualitatively by general purpose QCD Monte Carlo models that take into account the effect of densely-packed QCD strings in high multiplicity collisions. However, none of the tested models reproduce the data quantitatively. This work corroborates and extends the ALICE findings on strangeness production in proton-proton collisions at 7 TeV.

AbstractOne of the main tracking detectors of the forthcoming ALICE Experiment at the LHC is a cylindrical Time Projection Chamber (TPC) with an expected data volume of about 75 MByte per event. This data volume, in combination with the presumed maximum bandwidth of 1.2 GByte/s to the mass storage system, would limit the maximum event rate to 20 Hz. In order to achieve higher event rates, online data processing has to be applied. This implies either the detection and read-out of only those events which contain interesting physical signatures or an efficient compression of the data by modeling techniques. In order to cope with the anticipated data rate, massive parallel computing power is required. It will be provided in form of a clustered farm of SMP-nodes, based on off-the-shelf PCs, which are connected with a high bandwidth low overhead network. This High-Level Trigger (HLT) will be able to process a data rate of 25 GByte/s online. The front-end electronics of the individual sub-detectors is connected to the HLT via an optical link and a custom PCI card which is mounted in the clustered PCs. The PCI card is equipped with an FPGA necessary for the implementation of the PCI-bus protocol. Therefore, this FPGA can also be used to assist the host processor with first-level processing. The first-level processing done on the FPGA includes conventional cluster-finding for low multiplicity events and local track finding based on the Hough Transformation of the raw data for high multiplicity events.PACS: 07.05.-t Computers in experimental physics – 07.05.Hd Data acquisition: hardware and software – 29.85.+c Computer data analysis

(ProQuest: ... denotes formulae and/or non-USASCII text omitted; see image).We present a measurement of inclusive J/ psi production in p-Pb collisions at ... TeV as a function of the centrality of the collision, as estimated from the energy deposited in the Zero Degree Calorimeters. The measurement is performed with the ALICE detector down to zero transverse momentum, p sub(T), in the backward (-4.46 < y sub(cms) < -2.96) and forward (2.03 < y sub(cms) < 3.53) rapidity intervals in the dimuon decay channel and in the mid-rapidity region (-1.37 < y sub(cms) < 0.43) in the dielectron decay channel. The backward and forward rapidity intervals correspond to the Pb-going and p-going direction, respectively. The p sub(T)-differential J/ psi production cross section at backward and forward rapidity is measured for several centrality classes, together with the corresponding average p sub(T) and p sub(T2) values. The nuclear modification factor is presented as a function of centrality for the three rapidity intervals, and as a function of p sub(T) for several centrality classes at backward and forward rapidity. At mid- and forward rapidity, the J/ psi yield is suppressed up to 40% compared to that in pp interactions scaled by the number of binary collisions. The degree of suppression increases towards central p-Pb collisions at forward rapidity, and with decreasing p sub(T) of the J/ psi . At backward rapidity, the nuclear modification factor is compatible with unity within the total uncertainties, with an increasing trend from peripheral to central p-Pb collisions. [Figure not available: see fulltext.]

In the Queen Elizabeth Islands, regional distributions of vegetation and many summer climate patterns show similar, distinctive S-shaped patterns, a response to the interaction between regional topography and persistent northwesterly flow from the central Arctic Ocean. The cool and cloudy central polar pack ice climate bulges almost unimpeded into the low-lying islands of the northwest and north-central sector. This region has the least vascular plant diversity and is dominated almost entirely by herbaceous species. The mountains of Axel Heiberg and Ellesmere islands create a barrier that effectively shelters an intermontane region from both the central Arctic Ocean climate and travelling cyclonic systems. In this large intermontane zone regional minimums of cloud cover and maximums of temperatures and melt season duration are found. This area contains the most dense and diverse vascular plant assemblages. Woody species and sedges dominate, and many species with more southerly limits occur as disjuncts. The plateaus and highlands in the southern islands modify the central Arctic Ocean climate sufficiently to produce an intermediate climate. Woody species and sedges also dominate this area; however, the density and diversity are less than that of the intermontane area. Several phytogeographic limits occur in the Queen Elizabeth Islands, including the northern limits of woody plants and sedges, and the northern limits of the dominance of woody plants and sedges. These regional boundaries roughly coincide with regional mean July isotherms of 3 and 4°C respectively. /// Dans les îles de la Reine-Elizabeth, les distributions régionales de la végétation et de nombreux schémas climatiques d'été montrent des motifs particuliers semblables en forme de S, en réponse à l'interaction entre la topographie régionale et les courants constants du nordouest venant du centre de l'océan Arctique. Le climat du pack polaire central frais et nuageux pénètre pratiquement sans obstacle dans les îles basses du secteur nord-ouest et centre-nord. Cette région a le moins de variété de plantes vasculaires et elle est dominée presque entièrement par des espèces herbacées. Les montagnes de Axel Heiberg et des îles Ellesmere créent une barrière qui abrite de façon efficace une région intermontagneuse, à la fois du climat du centre de l'océan Arctique et des systèmes cycloniques qui passent au-dessus. Dans cette vaste zone intermontagneuse, on trouve des minimums régionaux de couverture nuageuse et des maximums de température et de durée de la saison de fonte. Cette zone contient les ensembles de plantes vasculaires les plus denses et les plus variés. Les espèces ligneuses et les cypéracées dominent, et de nombreuses espèces que l'on trouve généralement plus au sud, s'y trouvent sous forme d'espèces séparées. Les plateaux et hautes-terres dans les îles du sud modifient suffisamment le climat du centre de l'océan Arctique pour produire un climat intermédiaire. Des espèces ligneuses et des cypéracées dominent aussi dans cette région; cependant, leur densité et leur diversité sont moindres que celles de la zone intermontagneuse. On trouve plusieurs limites phytogéographiques dans les îles de la Reine-Elizabeth, y compris les limites nordiques des plantes ligneuses et des cypéracées et les limites nordiques de la dominance des plantes ligneuses et des cypéracées. Ces limites régionales coïncident en gros avec les isothermes moyens régionaux de juillet de 3 et 4° respectivement.

We present results on transverse momentum ([Formula: see text]) and rapidity ([Formula: see text]) differential production cross sections, mean transverse momentum and mean transverse momentum square of inclusive [Formula: see text] and [Formula: see text] at forward rapidity ([Formula: see text]) as well as [Formula: see text]-to-[Formula: see text] cross section ratios. These quantities are measured in pp collisions at center of mass energies [Formula: see text] and 13 TeV with the ALICE detector. Both charmonium states are reconstructed in the dimuon decay channel, using the muon spectrometer. A comprehensive comparison to inclusive charmonium cross sections measured at [Formula: see text], 7 and 8 TeV is performed. A comparison to non-relativistic quantum chromodynamics and fixed-order next-to-leading logarithm calculations, which describe prompt and non-prompt charmonium production respectively, is also presented. A good description of the data is obtained over the full [Formula: see text] range, provided that both contributions are summed. In particular, it is found that for [Formula: see text] GeV/ the non-prompt contribution reaches up to 50% of the total charmonium yield.

The invariant differential cross sections for inclusive [Formula: see text] and [Formula: see text] mesons at midrapidity were measured in pp collisions at [Formula: see text] TeV for transverse momenta [Formula: see text] GeV/ and [Formula: see text] GeV/ , respectively, using the ALICE detector. This large range in [Formula: see text] was achieved by combining various analysis techniques and different triggers involving the electromagnetic calorimeter (EMCal). In particular, a new single-cluster, shower-shape based method was developed for the identification of high-[Formula: see text] neutral pions, which exploits that the showers originating from their decay photons overlap in the EMCal. Above 4 GeV/[Formula: see text], the measured cross sections are found to exhibit a similar power-law behavior with an exponent of about 6.3. Next-to-leading-order perturbative QCD calculations differ from the measured cross sections by about 30% for the [Formula: see text], and between 30-50% for the [Formula: see text] meson, while generator-level simulations with PYTHIA 8.2 describe the data to better than 10-30%, except at [Formula: see text] GeV/[Formula: see text]. The new data can therefore be used to further improve the theoretical description of [Formula: see text] and [Formula: see text] meson production.

The azimuthal correlations of D mesons with charged particles were measured with the ALICE apparatus in pp collisions at [Formula: see text] and p-Pb collisions at [Formula: see text] at the Large Hadron Collider. [Formula: see text], [Formula: see text], and [Formula: see text] mesons and their charge conjugates with transverse momentum [Formula: see text] and rapidity in the nucleon-nucleon centre-of-mass system [Formula: see text] (pp collisions) and [Formula: see text] (p-Pb collisions) were correlated to charged particles with [Formula: see text]. The yield of charged particles in the correlation peak induced by the jet containing the D meson and the peak width are compatible within uncertainties in the two collision systems. The data are described within uncertainties by Monte-Carlo simulations based on PYTHIA, POWHEG, and EPOS 3 event generators.

Measurements of charged jet production as a function of centrality are presented for  p-Pb  collisions recorded at [Formula: see text] TeV with the ALICE detector. Centrality classes are determined via the energy deposit in neutron calorimeters at zero degree, close to the beam direction, to minimise dynamical biases of the selection. The corresponding number of participants or binary nucleon-nucleon collisions is determined based on the particle production in the Pb-going rapidity region. Jets have been reconstructed in the central rapidity region from charged particles with the anti-[Formula: see text] algorithm for resolution parameters [Formula: see text] and [Formula: see text] in the transverse momentum range 20 to 120 GeV/ . The reconstructed jet momentum and yields have been corrected for detector effects and underlying-event background. In the five centrality bins considered, the charged jet production in  p-Pb   collisions is consistent with the production expected from binary scaling from pp collisions. The ratio of jet yields reconstructed with the two different resolution parameters is also independent of the centrality selection, demonstrating the absence of major modifications of the radial jet structure in the reported centrality classes.

The production of K[Formula: see text](892)[Formula: see text] and [Formula: see text](1020) mesons has been measured in p-Pb collisions at [Formula: see text][Formula: see text] 5.02 TeV. K[Formula: see text] and [Formula: see text] are reconstructed via their decay into charged hadrons with the ALICE detector in the rapidity range [Formula: see text]. The transverse momentum spectra, measured as a function of the multiplicity, have a p[Formula: see text] range from 0 to 15 GeV/ for K[Formula: see text] and from 0.3 to 21 GeV/ for [Formula: see text]. Integrated yields, mean transverse momenta and particle ratios are reported and compared with results in pp collisions at [Formula: see text][Formula: see text] 7 TeV and Pb-Pb collisions at [Formula: see text][Formula: see text] 2.76 TeV. In Pb-Pb and p-Pb collisions, K[Formula: see text] and [Formula: see text] probe the hadronic phase of the system and contribute to the study of particle formation mechanisms by comparison with other identified hadrons. For this purpose, the mean transverse momenta and the differential proton-to-[Formula: see text] ratio are discussed as a function of the multiplicity of the event. The short-lived K[Formula: see text] is measured to investigate re-scattering effects, believed to be related to the size of the system and to the lifetime of the hadronic phase.

We report on the inclusive production cross sections of [Formula: see text], [Formula: see text], [Formula: see text](1S), [Formula: see text](2S) and [Formula: see text](3S), measured at forward rapidity with the ALICE detector in [Formula: see text] collisions at a center-of-mass energy [Formula: see text] TeV. The analysis is based on data collected at the LHC and corresponds to an integrated luminosity of 1.23 pb[Formula: see text]. Quarkonia are reconstructed in the dimuon-decay channel. The differential production cross sections are measured as a function of the transverse momentum [Formula: see text] and rapidity , over the [Formula: see text] ranges [Formula: see text] GeV/ for [Formula: see text], [Formula: see text] GeV/ for all other resonances, and for [Formula: see text]. The cross sections, integrated over [Formula: see text] and , and assuming unpolarized quarkonia, are [Formula: see text] [Formula: see text]b, [Formula: see text] [Formula: see text]b, [Formula: see text] nb, [Formula: see text] nb and [Formula: see text] nb, where the first uncertainty is statistical and the second one is systematic. These values agree, within at most [Formula: see text], with measurements performed by the LHCb collaboration in the same rapidity range.