167 research outputs found
CMS Monte Carlo production in the WLCG computing Grid
Monte Carlo production in CMS has received a major boost in performance and
scale since the past CHEP06 conference. The production system has been re-engineered in order
to incorporate the experience gained in running the previous system and to integrate production
with the new CMS event data model, data management system and data processing framework.
The system is interfaced to the two major computing Grids used by CMS, the LHC Computing
Grid (LCG) and the Open Science Grid (OSG).
Operational experience and integration aspects of the new CMS Monte Carlo production
system is presented together with an analysis of production statistics. The new system
automatically handles job submission, resource monitoring, job queuing, job distribution
according to the available resources, data merging, registration of data into the data
bookkeeping, data location, data transfer and placement systems. Compared to the previous
production system automation, reliability and performance have been considerably improved. A
more efficient use of computing resources and a better handling of the inherent Grid unreliability
have resulted in an increase of production scale by about an order of magnitude, capable of
running in parallel at the order of ten thousand jobs and yielding more than two million events
per day
The CMS Monte Carlo Production System: Development and Design
The CMS production system has undergone a major architectural upgrade from its predecessor, with the goal of reducing the operational manpower needed and preparing for the large scale production required by the CMS physics plan. The new production system is a tiered architecture that facilitates robust and distributed production request processing and takes advantage of the multiple Grid and farm resources available to the CMS experiment
Spectropolarimetric observations of an arch filament system with the GREGOR solar telescope
Arch filament systems occur in active sunspot groups, where a fibril
structure connects areas of opposite magnetic polarity, in contrast to active
region filaments that follow the polarity inversion line. We used the GREGOR
Infrared Spectrograph (GRIS) to obtain the full Stokes vector in the spectral
lines Si I 1082.7 nm, He I 1083.0 nm, and Ca I 1083.9 nm. We focus on the
near-infrared calcium line to investigate the photospheric magnetic field and
velocities, and use the line core intensities and velocities of the helium line
to study the chromospheric plasma. The individual fibrils of the arch filament
system connect the sunspot with patches of magnetic polarity opposite to that
of the spot. These patches do not necessarily coincide with pores, where the
magnetic field is strongest. Instead, areas are preferred not far from the
polarity inversion line. These areas exhibit photospheric downflows of moderate
velocity, but significantly higher downflows of up to 30 km/s in the
chromospheric helium line. Our findings can be explained with new emerging flux
where the matter flows downward along the fieldlines of rising flux tubes, in
agreement with earlier results.Comment: Proceedings 12th Potsdam Thinkshop to appear in Astronomische
Nachrichte
Rationality as the Rule of Reason
The demands of rationality are linked both to our subjective normative perspective (given that rationality is a person-level concept) and to objective reasons or favoring relations (given that rationality is non-contingently authoritative for us). In this paper, I propose a new way of reconciling the tension between these two aspects: roughly, what rationality requires of us is having the attitudes that correspond to our take on reasons in the light of our evidence, but only if it is competent. I show how this view can account for structural rationality on the assumption that intentions and beliefs as such involve competent perceptions of downstream reasons, and explore various implications of the account
OGLE-2012-BLG-0455/MOA-2012-BLG-206: Microlensing event with ambiguity in planetary interpretations caused by incomplete coverage of planetary signal
Characterizing a microlensing planet is done from modeling an observed
lensing light curve. In this process, it is often confronted that solutions of
different lensing parameters result in similar light curves, causing
difficulties in uniquely interpreting the lens system, and thus understanding
the causes of different types of degeneracy is important. In this work, we show
that incomplete coverage of a planetary perturbation can result in degenerate
solutions even for events where the planetary signal is detected with a high
level of statistical significance. We demonstrate the degeneracy for an
actually observed event OGLE-2012-BLG-0455/MOA-2012-BLG-206. The peak of this
high-magnification event exhibits very strong deviation
from a point-lens model with for data sets with a
total number of measurement 6963. From detailed modeling of the light curve, we
find that the deviation can be explained by four distinct solutions, i.e., two
very different sets of solutions, each with a two-fold degeneracy. While the
two-fold (so-called "close/wide") degeneracy is well-understood, the degeneracy
between the radically different solutions is not previously known. The model
light curves of this degeneracy differ substantially in the parts that were not
covered by observation, indicating that the degeneracy is caused by the
incomplete coverage of the perturbation. It is expected that the frequency of
the degeneracy introduced in this work will be greatly reduced with the
improvement of the current lensing survey and follow-up experiments and the
advent of new surveys.Comment: 5 pages, 3 figures, ApJ accepte
Mediating the Presence of Others: Reconceptualising Co-Presence as Mediated Intimacy
Drawing insight from queer and media studies, this article analyses data from the UK study Adults’ Media Lives. The authors claim that this study reveals the significance of people’s intimate relationships to their media practices, highlighting in particular how people’s media practices mediate the ‘presence’ of others. The authors put forward the concept of mediated intimacy to capture both the cultural intimacy people have with media and the mediation of intimacy by media practices. Mediating intimacy has implications for normative conceptions of intimate life, including the significance of ‘time’ to the values of ‘home’ and ‘work’
Spin asymmetry A_1^d and the spin-dependent structure function g_1^d of the deuteron at low values of x and Q^2
We present a precise measurement of the deuteron longitudinal spin asymmetry
A_1^d and of the deuteron spin-dependent structure function g_1^d at Q^2 < 1
GeV^2 and 4*10^-5 < x < 2.5*10^-2 based on the data collected by the COMPASS
experiment at CERN during the years 2002 and 2003. The statistical precision is
tenfold better than that of the previous measurement in this region. The
measured A_1^d and g_1^d are found to be consistent with zero in the whole
range of x.Comment: 17 pages, 10 figure
First Measurement of the Transverse Spin Asymmetries of the Deuteron in Semi-Inclusive Deep Inelastic Scattering
First measurements of the Collins and Sivers asymmetries of charged hadrons
produced in deep-inelastic scattering of muons on a transversely polarized
6-LiD target are presented. The data were taken in 2002 with the COMPASS
spectrometer using the muon beam of the CERN SPS at 160 GeV/c. The Collins
asymmetry turns out to be compatible with zero, as does the measured Sivers
asymmetry within the present statistical errors.Comment: 6 pages, 2 figure
Measurement of the Spin Structure of the Deuteron in the DIS Region
We present a new measurement of the longitudinal spin asymmetry A_1^d and the
spin-dependent structure function g_1^d of the deuteron in the range 1 GeV^2 <
Q^2 < 100 GeV^2 and 0.004< x <0.7. The data were obtained by the COMPASS
experiment at CERN using a 160 GeV polarised muon beam and a large polarised
6-LiD target. The results are in agreement with those from previous experiments
and improve considerably the statistical accuracy in the region 0.004 < x <
0.03.Comment: 10 pages, 6 figures, subm. to PLB, revised: author list, Fig. 4,
details adde
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