20,431 research outputs found
Prospect of D0 mixing and CPV at LHCb
Precision measurements in charm physics offer a window into a unique sector
of potential New Physics interactions. LHCb is poised to become a world leading
experiment for charm studies, recording enormous statistics with a detector
tailored for flavor physics. This article presents recent charm CPV and mixing
studies from LHCb, including LHCb's first CP asymmetry measurement with 37
inverse pb of data collected in 2010. The difference of the CP asymmetries of
D0 decays to the K-K+ and \pi-\pi+ final states is determined to be \Delta
A_{CP} = (-0.28 +/- 0.70 +/- 0.25)%. Significant updates to the material
presented at the 4th International Workshop on Charm Physics are included.Comment: 5 pages, 4 figures. Submitted to the proceedings of the 4th
International Workshop on Charm Physics (Charm2010), Beijing, Chin
Financial Literacy: What Are Business Schools Teaching?
The financial illiteracy of Americans has attracted the attention and funds of more than 10 federal agencies and countless other state agencies and non-profit organizations. The manifestations of poor financial skills and planning are divorce, depression, and many elderly Americans living in poverty.
Hundreds of business and non-business college students have been surveyed. Both groups were found to be financially illiterate. We examined the curricula of 100 AACSB institutions and concluded that business schools are either not offering fundamental courses in personal financial planning or that the courses are not generally available to business students (for credit) or non-business students.
It is ironic that college students are graduating with the required 60 credits in the liberal arts, but are not required to pass a course in personal finance. We feel strongly that it is time for business faculty, specifically finance faculty, to argue that being financially literate is as important as being literate in English and the sciences
Exact versus approximate beaming formulas in Gamma-Ray Burst afterglows
We present the exact analytic expressions to compute, assuming the emitted
Gamma-Ray Burst (GRB) radiation is not spherically symmetric but is confined
into a narrow jet, the value of the detector arrival time at which we start to
"see" the sides of the jet, both in the fully radiative and adiabatic regimes.
We obtain this result using our exact analytic expressions for the EQuiTemporal
Surfaces (EQTSs) in GRB afterglows. We re-examine the validity of three
different approximate formulas currently adopted for the adiabatic regime in
the GRB literature. We also present an empirical fit of the numerical solutions
of the exact equations, compared and contrasted with the three above
approximate formulas. The extent of the differences is such as to require a
reassessment on the existence and entity of beaming in the cases considered in
the current literature, as well as on its consequences on the GRB energetics.Comment: 4 pages, 4 figures, to appear on ApJ Let
ATLAS RPC offline monitoring and data quality assessment
In this work several aspects of ATLAS RPC offline monitoring and data quality
assessment are illustrated with cosmics data selected by RPC trigger. These
correspond to trigger selection, front-end mapping, detection efficiency and
occupancy, which are studied in terms of low level quantities such as: RPC
off-line hits and standalone tracks. The tools and techniques presented are
also extended to the forthcoming LHC p-p beam collisions.Comment: Poster section at ICHEP08, Philadelphia, USA, July 2008. 3 pages,
LaTeX, 3 eps figure
Distributed PC Based Routers: Bottleneck Analysis and Architecture Proposal
Recent research in the different functional areas of modern routers have made proposals that can greatly increase the efficiency of these machines. Most of these proposals can be implemented quickly and often efficiently in software. We wish to use personal computers as forwarders in a network to utilize the advances made by researchers. We therefore examine the ability of a personal computer to act as a router. We analyze the performance of a single general purpose computer and show that I/O is the primary bottleneck. We then study the performance of distributed router composed of multiple general purpose computers. We study the performance of a star topology and through experimental results we show that although its performance is good, it lacks flexibility in its design. We compare it with a multistage architecture. We conclude with a proposal for an architecture that provides us with a forwarder that is both flexible and scalable.© IEE
Statistical mechanics and thermodynamics of viral evolution
This paper analyzes a simplified model of viral infection and evolution using
the 'grand canonical ensemble' and formalisms from statistical mechanics and
thermodynamics to enumerate all possible viruses and to derive thermodynamic
variables for the system. We model the infection process as a series of energy
barriers determined by the genetic states of the virus and host as a function
of immune response and system temperature. We find a phase transition between a
positive temperature regime of normal replication and a negative temperature
'disordered' phase of the virus. These phases define different regimes in which
different genetic strategies are favored. Perhaps most importantly, it
demonstrates that the system has a real thermodynamic temperature. For normal
replication, this temperature is linearly related to effective temperature. The
strength of immune response rescales temperature but does not change the
observed linear relationship. For all temperatures and immunities studied, we
find a universal curve relating the order parameter to viral evolvability. Real
viruses have finite length RNA segments that encode for proteins which
determine their fitness; hence the methods put forth here could be refined to
apply to real biological systems, perhaps providing insight into immune escape,
the emergence of novel pathogens and other results of viral evolution.Comment: 39 pages (55 pages including supplement), 9 figures, 11 supplemental
figure
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