82 research outputs found
Randall-Sundrum Corrections to the Width Difference and CP-Violating Phase in -Meson Decays
We study the impact of the Randall-Sundrum setup on the width difference
and the CP-violating phase in the - system. Our calculations are performed in the general framework
of an effective theory, based on operator product expansion. The result can
thus be used for many new physics models. We find that the correction to the
magnitude of the decay amplitude is below 4% for a realistic
choice of input parameters. The main modification in the
-plane is caused by a new CP-violating phase in the
mixing amplitude, which allows for a better agreement with the experimental
results of CDF and D\O from decays. The
best-fit value of the CP asymmetry can be reproduced, while
simultaneously the theoretical prediction for the semileptonic CP asymmetry
can enter the range.Comment: 12 pages, 1 table, 3 figures, references added, comments added, minor
correction in numerics, conclusions unchanged, accepted for publication in
Physical Review
Genetics and the Archaeology of Ancient Israel
This paper is a call for DNA testing on ancient skeletal materials from the southern Levant to begin to database genetic information of the inhabitants of this crossroads region. Archaeologists and biblical historians view the earliest presence in the region of a group that called itself Israel in the Iron I period, traditionally dated to ca. 1200-1000 BCE. These were in villages in the varied hill countries of the region, contemporary with urban settlements in the coastal plains, inland valleys, and central Hill Country attributed to varied indigenous groups collectively called Canaanite. The remnants of Egyptian imperial presence in the region lasted until around 1150 BCE, postdating the arrival of an immigrant group from the Aegean called the Philistines ca. 1175 BCE. The period that follows the Iron I in the southern Levant is marked by the development of territorial states throughout the region, ca. 1000-800 BCE. These patrimonial kingdoms, including the United Kingdom of Israel and the divided kingdoms of northern Israel and Judah, coalesced varied peoples under central leadership and newly founded administrative and religious bureaucracies. Ancient DNA testing will give us a further refined understanding of the individuals who peopled the region of the southern Levant throughout its varied archaeological and historic periods, and put forward scientific data that will support, refute, or nuance our socio-historic reconstruction of ancient group identities. These social identities may or may not map onto genetic data, and without sampling of ancient DNA we may never know. A database of ancient DNA will also allow for comparisons with modern DNA samples collected throughout the greater region and the Mediterranean littoral, giving a more robust understanding of the long historical trajectories of regional human genetics and the genetics of varied ancestral groups of today’s Jewish populations and other cultural groups in the modern Middle East and Mediterranean
Rare B decays and Tevatron top-pair asymmetry
The recent Tevatron result on the top quark forward-backward asymmetry, which
deviates from its standard model prediction by 3.4, has prompted many
authors to build new models to account for this anomaly. Among the various
proposals, we find that those mechanisms which produce via - or
-channel can have a strong correlation to the rare B decays. We demonstrate
this link by studying a model with a new charged gauge boson, . In terms of
the current measurements on decays, we conclude that the branching
ratio for is affected most by the new effects.
Furthermore, using the world average branching ratio for the exclusive B decays
at level, we discuss the allowed values for the new parameters.
Finally, we point out that the influence of the new physics effects on the
direct CP asymmetry in B decays is insignificant.Comment: 15 page, 6 figures, typos corrected and references added, final
version to appear journa
The Custodial Randall-Sundrum Model: From Precision Tests to Higgs Physics
We reexamine the Randall-Sundrum (RS) model with enlarged gauge symmetry
SU(2)_L x SU(2)_R x U(1)_X x P_LR in the presence of a brane-localized Higgs
sector. In contrast to the existing literature, we perform the Kaluza-Klein
(KK) decomposition within the mass basis, which avoids the truncation of the KK
towers. Expanding the low-energy spectrum as well as the gauge couplings in
powers of the Higgs vacuum expectation value, we obtain analytic formulas which
allow for a deep understanding of the model-specific protection mechanisms of
the T parameter and the left-handed Z-boson couplings. In particular, in the
latter case we explain which contributions escape protection and identify them
with the irreducible sources of P_LR symmetry breaking. We furthermore show
explicitly that no protection mechanism is present in the charged-current
sector confirming existing model-independent findings. The main focus of the
phenomenological part of our work is a detailed discussion of Higgs-boson
couplings and their impact on physics at the CERN Large Hadron Collider. For
the first time, a complete one-loop calculation of all relevant Higgs-boson
production and decay channels is presented, incorporating the effects stemming
from the extended electroweak gauge-boson and fermion sectors.Comment: 74 pages, 13 figures, 3 tables. v2: Matches version published in JHE
Estimated burden of group a streptococcal pharyngitis among children in Beijing, China
Status of research and development of vaccines for Streptococcus pyogenes.
Streptococcus pyogenes is an important global pathogen, causing considerable morbidity and mortality, especially in low and middle income countries where rheumatic heart disease and invasive infections are common. There is a number of promising vaccine candidates, most notably those based on the M protein, the key virulence factor for the bacterium. Vaccines against Streptococcus pyogenes are considered as impeded vaccines because of a number of crucial barriers to development. Considerable effort is needed by key players to bring current vaccine candidates through phase III clinical trials and there is a clear need to develop a roadmap for future development of current and new candidates
Improving performance in medical practices through the extended use of electronic medical record systems: a survey of Canadian family physicians
Cognitive screening among acute respiratory failure survivors: a cross-sectional evaluation of the Mini-Mental State Examination
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