154 research outputs found
Direct CP Violation in B decays with rho0-omega Mixing
A complete study of the process B to pi+ pi- V(V=1--) is performed both in
the framework of the helicity formalism and the effective lagrangian approach.
Emphasis is put on the factorization hypothesis and the importance of the rho0-
omega mixing in enhancing the direct CP violation. New results involving some
branching ratios and the ratio of the Penguin/Tree amplitude are given in
details.Comment: 7 pages, 2 figures. Talk oresented by ZJA at the 18th International
Workshop on High energy Physics and Quantum Field Theory, QFTHEP004,
St-Petersbug, RUSSIA, JUne 17-23, 200
4D Emittance Measurements Using Multiple Wire and Waist Scan Methods in the ATF Extraction Line.
TUPC087International audienceEmittance measurements performed in the diagnostic section of the ATF extraction line since 1998 lead to ver- tical emittances three times larger than the expected ones, with a strong dependence on intensity. An experimental program is pursued to investigate potential sources of emit- tance growth and find possible remedies. This requires ef- ficient and reliable emittance measurement techniques. In the past, several phase-space reconstruction methods devel- oped at SLAC and KEK have been used to estimate the ver- tical emittance, based on multiple location beam size mea- surements and dedicated quadrupole scans. These methods have been shown to be very sensitive to measurement er- rors and other fluctuations in the beam conditions. In this context new emittance measurements have been performed revisiting these methods and newly developed ones with a systematic approach to compare and characterise their per- formance in the ATF extraction line
Параметрична логістична модель планування роботи різних видів транспорту
Запропонована логістична модель планування роботи різних видів транспорту вантажної станції за умов ефективного використання вантажно-розвантажувальних механізмів, вантажних фронтів та складської обробки вантажів.Предложенная логистическая модель планирования работы различных видов транспорта грузовой станции в условиях эффективного использования погрузочно-разгрузочных механизмов, грузовых фронтов и складской обработки грузов.The proposed model of logistic planning of transport modes cargo station for the effective use of material handling equipment, commercial fronts and warehouse handling
Status of the Super-B factory Design
The SuperB international team continues to optimize the design of an
electron-positron collider, which will allow the enhanced study of the origins
of flavor physics. The project combines the best features of a linear collider
(high single-collision luminosity) and a storage-ring collider (high repetition
rate), bringing together all accelerator physics aspects to make a very high
luminosity of 10 cm sec. This asymmetric-energy collider
with a polarized electron beam will produce hundreds of millions of B-mesons at
the (4S) resonance. The present design is based on extremely low
emittance beams colliding at a large Piwinski angle to allow very low
without the need for ultra short bunches. Use of crab-waist
sextupoles will enhance the luminosity, suppressing dangerous resonances and
allowing for a higher beam-beam parameter. The project has flexible beam
parameters, improved dynamic aperture, and spin-rotators in the Low Energy Ring
for longitudinal polarization of the electron beam at the Interaction Point.
Optimized for best colliding-beam performance, the facility may also provide
high-brightness photon beams for synchrotron radiation applications
Design of an interaction region with head-on collisions for the ILC
An interaction region (IR) with head-on collisions is considered as an
alternative to the baseline configuration of the International Linear Collider
(ILC) which includes two IRs with finite crossing-angles (2 and 20 mrad).
Although more challenging for the beam extraction, the head-on scheme is
favoured by the experiments because it allows a more convenient detector
configuration, particularly in the forward region. The optics of the head-on
extraction is revisited by separating the e+ and e- beams horizontally, first
by electrostatic separators operated at their LEP nominal field and then using
a defocusing quadrupole of the final focus beam line. In this way the septum
magnet is protected from the beamstrahlung power. Newly optimized final focus
and extraction optics are presented, including a first look at post-collision
diagnostics. The influence of parasitic collisions is shown to lead to a region
of stable collision parameters. Disrupted beam and beamstrahlung photon losses
are calculated along the extraction elements
Baseline Design of the SuperB Factory Injection System
TUPPR088International audienceThe injection complex of the SuperB, B-factory project of INFN consists of a polarized electron gun, a positron production system, electron and positron linac sections, a positron damping ring and the transfer lines connecting these systems and the collider main rings. To keep the ultra high luminosity nearly constant, continuous injection of 4 GeV electrons and 7 GeV positrons in both Low Energy Ring (LER) and High Energy Ring (HER) is necessary. In this paper we describe the baseline design and the beam dynamics studies performed to evaluate the system performance
SuperB: next-generation e+e- B-factory collider
International audienceThe SuperB international team continues to optimize the design of an electron-positron collider, which will allow the enhanced study of the origins of flavor physics. The project combines the best features of a linear collider (high single- collision luminosity) and a storage-ring collider (high rep- etition rate), bringing together all accelerator physics as- pects to make a very high luminosity of 10^36 cm^−2 sec^−1 . This asymmetric-energy collider with a polarized electron beam will produce hundreds of millions of B-mesons at the Υ(4S) resonance. The present design is based on ex- tremely low emittance beams colliding at a large Piwin- ski angle to allow very low β⋆y without the need for ultra short bunches. Use of crab-waist sextupoles will enhance the luminosity, suppressing dangerous resonances and al- lowing for a higher beam-beam parameter. The project has flexible beam parameters, improved dynamic aperture, and spin-rotators in the Low Energy Ring for longitudinal po- larization of the electron beam at the Interaction Point. Op- timized for best colliding-beam performance, the facility may also provide high-brightness photon beams for syn- chrotron radiation applications
Derived variants at six genes explain nearly half of size reduction in dog breeds
Selective breeding of dogs by humans has generated extraordinary diversity in body size. A number of multibreed analyses have been undertaken to identify the genetic basis of this diversity. We analyzed four loci discovered in a previous genome-wide association study that used 60,968 SNPs to identify size-associated genomic intervals, which were too large to assign causative roles to genes. First, we performed fine-mapping to define critical intervals that included the candidate genes GHR, HMGA2, SMAD2, and STC2, identifying five highly associated markers at the four loci. We hypothesize that three of the variants are likely to be causative. We then genotyped each marker, together with previously reported size-associated variants in the IGF1 and IGF1R genes, on a panel of 500 domestic dogs from 93 breeds, and identified the ancestral allele by genotyping the same markers on 30 wild canids. We observed that the derived alleles at all markers correlated with reduced body size, and smaller dogs are more likely to carry derived alleles at multiple markers. However, breeds are not generally fixed at all markers; multiple combinations of genotypes are found within most breeds. Finally, we show that 46%–52.5% of the variance in body size of dog breeds can be explained by seven markers in proximity to exceptional candidate genes. Among breeds with standard weights <41 kg (90 lb), the genotypes accounted for 64.3% of variance in weight. This work advances our understanding of mammalian growth by describing genetic contributions to canine size determination in non-giant dog breeds
Analysis of large versus small dogs reveals three genes on the canine X chromosome associated with body weight, muscling and back fat thickness
International audienceDomestic dog breeds display significant diversity in both body mass and skeletal size, resulting from intensive selective pressure during the formation and maintenance of modern breeds. While previous studies focused on the identification of alleles that contribute to small skeletal size, little is known about the underlying genetics controlling large size. We first performed a genome-wide association study (GWAS) using the Illumina Canine HD 170,000 single nucleotide polymorphism (SNP) array which compared 165 large-breed dogs from 19 breeds (defined as having a Standard Breed Weight (SBW) >41 kg [90 lb]) to 690 dogs from 69 small breeds (SBW ≤41 kg). We identified two loci on the canine X chromosome that were strongly associated with large body size at 82–84 megabases (Mb) and 101–104 Mb. Analyses of whole genome sequencing (WGS) data from 163 dogs revealed two indels in the Insulin Receptor Substrate 4 (IRS4) gene at 82.2 Mb and two additional mutations, one SNP and one deletion of a single codon, in Immunoglobulin Superfamily member 1 gene (IGSF1) at 102.3 Mb. IRS4 and IGSF1 are members of the GH/IGF1 and thyroid pathways whose roles include determination of body size. We also found one highly associated SNP in the 5’UTR of Acyl-CoA Synthetase Long-chain family member 4 (ACSL4) at 82.9 Mb, a gene which controls the traits of muscling and back fat thickness. We show by analysis of sequencing data from 26 wolves and 959 dogs representing 102 domestic dog breeds that skeletal size and body mass in large dog breeds are strongly associated with variants within IRS4, ACSL4 and IGSF1
ATF2 COMMISSIONING
ATF2 is a final-focus test beam line that aims to focus the low-emittance beam from the ATF damping ring to a beam size of about 37 nm, and at the same time to demonstrate nm beam stability, using numerous advanced beam diagnostics and feedback tools. The construction has been finished at the end of 2008 and the beam commissioning of ATF2 has started in December of 2008. ATF2 is constructed and commissioned by ATF international collaborations with strong US, Asian and European participation
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