443,964 research outputs found
Commissioning of the CMS High Level Trigger
The CMS experiment will collect data from the proton-proton collisions
delivered by the Large Hadron Collider (LHC) at a centre-of-mass energy up to
14 TeV. The CMS trigger system is designed to cope with unprecedented
luminosities and LHC bunch-crossing rates up to 40 MHz. The unique CMS trigger
architecture only employs two trigger levels. The Level-1 trigger is
implemented using custom electronics, while the High Level Trigger (HLT) is
based on software algorithms running on a large cluster of commercial
processors, the Event Filter Farm. We present the major functionalities of the
CMS High Level Trigger system as of the starting of LHC beams operations in
September 2008. The validation of the HLT system in the online environment with
Monte Carlo simulated data and its commissioning during cosmic rays data taking
campaigns are discussed in detail. We conclude with the description of the HLT
operations with the first circulating LHC beams before the incident occurred
the 19th September 2008
Short-duration lensing events: II. Expectations and Protocols
Ongoing microlensing observations by OGLE and MOA regularly identify and
conduct high-cadence sampling of lensing events with Einstein diameter crossing
time, tau_E, of 16 or fewer days. Events with estimated values of tau_E of one
to two days have been detected. Short duration events tend to be generated by
low-mass lenses or by lenses with high transverse velocities. We compute the
expected rates, demonstrate the expected ranges of parameters for lenses of
different mass, and develop a protocol for observing and modeling
short-duration events. Relatively minor additions to the procedures presently
used will increase the rate of planet discovery, and also discover or place
limits on the population of high-speed dim stars and stellar remnants in the
vicinity of the Sun.Comment: 17 pages; 3 figures; submitted to ApJ 3 July 200
Compact cosmic ray detector for unattended atmospheric ionisation monitoring
Two vertical cosmic ray telescopes for atmospheric cosmic ray ionization event detection are compared.
Counter A, designed for low power remote use, was deployed in the Welsh mountains; its
event rate increased with altitude as expected from atmospheric cosmic ray absorption. Independently,
Counter B’s event rate was found to vary with incoming particle acceptance angle. Simultaneous colocated
comparison of both telescopes exposed to atmospheric ionization showed a linear relationship
between their event rates
A Research Documentation On Men's Sexual Health Disclosed
When VigRX Plus was surveyed by Vedic Life-Sciences in proved to be the best pill treatment for sexual health. Here is what the study reveals
Compact object detection in self-lensing binary systems with a main-sequence star
Detecting compact objects by means of their gravitational lensing effect on
an observed companion in a binary system has already been suggested almost four
decades ago. However, these predictions were made even before the first
observations of gravitational lensing, whereas nowadays gravitational
microlensing surveys towards the Galactic bulge yield almost 1000 events per
year where one star magnifies the light of a more distant one. With a specific
view on those experiments, we therefore carry out simulations to assess the
prospects for detection of the transient periodic magnification of the
companion star, which lasts typically only a few hours binaries involving a
main-sequence star. We find that detectability is given by the achievability of
dense monitoring with the required photometric accuracy. In sharp contrast to
earlier expectations by other authors, we find that main-sequence stars are not
substantially less favourable targets to observe this effect than white dwarfs.
The requirement of an almost edge-on orbit leads to a probability of the order
of for spotting the signature of an existing compact object
in a binary system with this technique. Assuming an abundance of such systems
about 0.4 per cent, a high-cadence monitoring every 15~min with 5 per cent
photometric accuracy would deliver a signal rate per target star of \gamma
\sim 4 \times 10^{-7}~\mbox{yr}^{-1} at a recurrence period of about 6 months.
With microlensing surveys having demonstrated the capability to monitor about
stars, one is therefore provided with the chance to detect
roughly semi-annually recurring self-lensing signals from several compact
compacts in a binary system. If the photometric accuracy was pushed down to 0.3
per cent, 10 times as many signals would become detectable.Comment: 7 pages, 5 figures, accepted in MNRA
Disappearing private reputations in long-run relationships
For games of public reputation with uncertainty over types and imperfect public monitoring, Cripps et al. [Imperfect monitoring and impermanent reputations, Econometrica 72 (2004) 407–432] showed that an informed player facing short-lived uninformed opponents cannot maintain a permanent reputation for playing a strategy that is not part of an equilibrium of the game without uncertainty over types. This paper extends that result to games in which the uninformed player is long-lived and has private beliefs, so that the informed player's reputation is private. The rate at which reputations disappear is uniform across equilibria and reputations also disappear in sufficiently long discounted finitely repeated games
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