3,319 research outputs found
Physics of the ALICE Experiment
A short description of the ALICE detector at CERN is given. The experiment is
aiming to study the properties of the quark-gluon plasma by means of a whole
set of probes that can be subdivided into three classes: soft, heavy-flavour
and high-Pt probes. Each of the classes is illustrated by a few typical
examples.Comment: Proceedings of the 41st Rencontres de Moriond, QCD and high energy
hadronic interactions, La Thuile, Italy, 18-25 March 200
The harmonic measure of diffusion-limited aggregates including rare events
We obtain the harmonic measure of diffusion-limited aggregate (DLA) clusters using a biased random-walk sampling technique which allows us to measure probabilities of random walkers hitting sections of clusters with unprecedented accuracy; our results include probabilities as small as 10- 80. We find the multifractal D(q) spectrum including regions of small and negative q. Our algorithm allows us to obtain the harmonic measure for clusters more than an order of magnitude larger than those achieved using the method of iterative conformal maps, which is the previous best method. We find a phase transition in the singularity spectrum f(α) at α≈14 and also find a minimum q of D(q), qmin=0.9±0.05
Structure of a Solvated Nickel(II) Complex of (\u3cem\u3eS\u3c/em\u3e)-2\u27-(\u3cem\u3eN\u3c/em\u3e-benzylprolyl)aminoacetophenone and (\u3cem\u3eR\u3c/em\u3e)-valine Schiff base, C\u3csub\u3e25\u3c/sub\u3eH\u3csub\u3e29\u3c/sub\u3eN\u3csub\u3e3\u3c/sub\u3eNiO\u3csub\u3e3\u3c/sub\u3e.1/2C\u3csub\u3e4\u3c/sub\u3eH\u3csub\u3e8\u3c/sub\u3eO. Conformational Calculation of Diastereomeric Complexes of (\u3cem\u3eR\u3c/em\u3e)-valine and (\u3cem\u3eS\u3c/em\u3e)-valine
Large XCH 4 anomaly in summer 2013 over northeast Asia observed by GOSAT
Extremely high levels of column-averaged dry-air mole fractions of atmospheric methane (XCH4) were detected in August and September 2013 over northeast Asia (∼ 20 ppb above the averaged summertime XCH4 over 2009–2012, after removing a long-term trend), as being retrieved from the Short-Wavelength InfraRed (SWIR) spectral data observed with the Thermal And Near-infrared Sensor for carbon Observation – Fourier Transform Spectrometer (TANSO-FTS) onboard Greenhouse Gases Observing Satellite (GOSAT). Similar enhancements of XCH4 were also observed by the ground-based measurements at two Total Carbon Column Observing Network (TCCON) sites in Japan
Regional impact of Ozone precursor emissions on NO<sub>x</sub> and O<sub>3</sub> levels at ZOTTO tall tower in Central Siberia
Investigation of high power laser-induced spallation phenomena in target and collimator materials for next generation accelerators
On the local birth place of Geminga
Using estimates of the distance and proper motion of Geminga and the
constraints on its radial velocity posed by the shape of its bow shock, we
investigate its birth place by tracing its space motion backwards in time. Our
results exclude the lambda Ori association as the origin site because of the
large distance between both objects at any time. Our simulations place the
birth region at approximately 90-240 pc from the Sun, between 197 degrees and
199 degrees in Galactic longitude and -16 degrees and -8 degrees in latitude,
most probably inside the Cas-Tau OB association or the Ori OB1a association. We
discard the possibility of the progenitor being a massive field star. The
association of Geminga with either stellar association implies an upper limit
of M = 15 Msun for the mass of its progenitor. We also propose new members for
the Cas-Tau and Ori OB1 associations.Comment: 6 pages, 5 figures. Accepted for publication in Astronomy &
Astrophysic
Modeling the Near-Infrared Luminosity Functions of Young Stellar Clusters
We present the results of numerical experiments designed to evaluate the
usefulness of near-infrared luminosity functions for constraining the Initial
Mass Function (IMF) of young stellar populations. From this numerical modeling,
we find that the luminosity function of a young stellar population is
considerably more sensitive to variations in the underlying initial mass
function than to either variations in the star forming history or assumed
pre-main-sequence (PMS) mass-to-luminosity relation. To illustrate the
potential effectiveness of using the KLF of a young cluster to constrain its
IMF, we model the observed K band luminosity function of the nearby Trapezium
cluster. Our derived mass function for the Trapezium spans two orders of
magnitude in stellar mass (5 Msun to 0.02 Msun), has a peak near the hydrogen
burning limit, and has an IMF for Brown Dwarfs which steadily decreases with
decreasing mass.Comment: To appear in ApJ (1 April 2000). 37 pages including 11 figures, AAS:
ver 5.
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