263 research outputs found
CP violating angular asymmetries of b and bbar quarks in e+e- -> t tbar
We obtain analytical formulae for the cross section and the angular
distributions of the b(bbar) quarks in the process e+e- -> t tbar, with t -> W+
b (tbar -> W- bbar) assuming CP violation in the \gamma t tbar and Z t tbar
vertices. We present CP violating asymmetries, which measure separately the
real and imaginary parts of the electroweak dipole moment form factors of the
top, d^{\gamma}(s) and d^{Z}(s). We give a numerical analysis of these
asymmetries within the Minimal Supersymmetric Standard Model with complex
parameters. They turn out to be of order <= 10^{-3}.Comment: 22 pages LaTeX with 3x3 figures included; some definitions for
polarization asymmetries and some notations are changed and some references
adde
General Flavor Blind MSSM and CP Violation
We study the implications on flavor changing neutral current and CP violating
processes in the context of supersymmetric theories without a new flavor
structure (flavor blind supersymmetry). The low energy parameters are
determined by the running of the soft breaking terms from the grand unified
scale with SUSY phases consistent with the EDM constraints. We find that the CP
asymmetry in b --> s gamma can reach large values potentially measurable at B
factories, especially in the low BR(b --> s gamma) region. We perform a fit of
the unitarity triangle including all the relevant observables. In this case, no
sizeable deviations from the SM expectations are found. Finally we analyze the
SUSY contributions to the anomalous magnetic moment of the muon pointing out
its impact on the b --> s gamma CP asymmetry and on the SUSY spectrum including
chargino and stop masses.Comment: 40 pages, 8 figures, typos corrected, references adde
General Flavour Blind MSSM and CP Violation
We study FCNC and CP violating processes in the MSSM without a new flavour
structure (flavour blind MSSM). The low energy parameters are determined by the
running of the soft breaking terms from the GUT scale with SUSY phases
consistent with the EDM constraints. We find that the CP asymmetry in b -> s
gamma can reach large values potentially measurable at B factories, especially
in the low BR(b -> s gamma) region. We analyze the SUSY contributions to the
anomalous magnetic moment of the muon pointing out its impact on the b -> s
gamma CP asymmetry and on the SUSY spectrum.Comment: LaTex, 5 pages, 2 figures, Contribution to the International
Europhysics Conference on High Energy Physics (HEP 2001), Budapest, Hungary,
12-18 Jul 200
Seesaw neutrinos with one right-handed singlet field and a second Higgs doublet
We study parameters of an extension of the Standard Model. The neutrino
sector is enlarged by one right-handed singlet field, allowing for the seesaw
mechanism type-I, and the Higgs sector contains one additional doublet, which
contributes to light neutrino masses through one-loop radiative corrections.
Employing an approximation for the effective light neutrino mass matrix we
express the masses of the light neutrinos analytically, allowing us to
parametrize the Yukawa couplings to neutrinos by the experimental measurements
on the neutrino sector and only two free parameters. We focus on a
CP-conserving Higgs potential for which we present the allowed ranges of the
input parameters and a statistical overview over the possible values of the
Yukawa couplings.Comment: 35 pages, 9 figures; v2: one figure and references added, some minor
changes to the tex
p-Dimethylaminobenzaldehyde-reactive substances in tail tendon collagen of streptozotocin-diabetic rats: temporal relation to biomechanical properties and advanced glycation endproduct (AGE)-related fluorescence
AbstractIn the present work, pepsin digests of tail tendons from streptozotocin-diabetic rats were found to contain material that reacted rapidly at room temperature with p-dimethylaminobenzaldehyde (Ehrlich’s reagent) to give an adduct with an absorbance spectrum characteristic of the Ehrlich chromogen of pyrrolic nature determined in ageing collagens. A significant correlation of the Ehrlich adduct with tendon mechanical strength and collagen fluorescence characteristic of advanced glycation endproducts was observed. Collagen content of the Ehrlich-positive material was found to be significantly elevated in tendons of diabetic rats compared with age-matched healthy controls. The results indicate that the p-dimethylaminobenzaldehyde-reactive pyrrole moieties may contribute to the increased cross-linking of diabetic matrix collagen. Profound inhibitory effect of aminoguanidine was observed, underlining the role of non-enzymatic mechanisms of advanced glycation in pyrrolisation and cross-linking of collagen exposed to hyperglycaemia. It is hypothesised that quantification of the p-dimethylaminobenzaldehyde-reactive material in matrix collagen may provide a tissue measure of integrated hyperglycaemia over prolonged periods of time. Further research is to assess the significance of p-dimethylaminobenzaldehyde-reactive substances in diabetic collagen tissues and to reveal their relationship to enzyme-mediated physiological pyrrolisation of ageing collagens
Triple product correlations in top squark decays
We propose several T-odd asymmetries in the decay chains of the top squarks
and and , for . We
calculate the asymmetries within the Minimal Supersymmetric Standard Model with
complex parameters , and . We give the analytic formulae for
the decay distributions. We present numerical results for the asymmetries and
estimate the event rates necessary to observe them. The largest T-odd asymmetry
can be as large as 40%.Comment: 26 pages, 5 figures; misprints corrected; reference adde
Reliability of knee joint position sense measurement: a comparison between goniometry and image capture methods
Aims: Evaluate the intra-rater and inter-rater reliability of hand-held goniometry compared to image capture (IMC) in the assessment of joint position sense (JPS) in healthy participants. Methodology: Repeated-measures observational study design was undertaken with 36 asymptomatic university students of both genders aged between 18 to 45 years. JPS in the knee was assessed by two assessors over two sessions (one-week interval) using hand-held goniometry and IMC methods. Joint position sense was assessed at four target knee flexion angles. Intra- and inter-rater reliability was assessed with absolute error (AE), relative error (RE) and intra-class correlation coefficient. Findings: Inter-rater reliability for goniometry was poor to substantial (ICC: 0.00 to 0.64) and was poor to moderate (ICC: 0.00 to 0.47) for IMC. Intra-rater reliability for goniometry was poor to moderate (ICC: 0.00 to 0.42) and poor to moderate for IMC (ICC: 0.00 to 0.41). AE for goniometry ranged from 3.2° to 8.6°, with RE from 0.1°-8.3°. For IMC, AE for goniometry was 5.3° to 12.5°, with RE ranging from 0.1° to 11.1°. Principal Conclusions: Neither goniometry nor IMC appeared superior to the other in JPS assessment. Caution should be made when considering the reliability for goniometry and IMC before clinical assessment is made
Electron Electric Dipole Moment from Lepton Flavor Violation
The general Minimal Supersymmetric Standard Model introduces new sources for
Lepton Flavor Violation (LFV) as well as CP-violation. In this paper, we show
that when both sources are present, the electric dipole moment of the electron,
, receives a contribution from the phase of the trilinear -term of
staus, . For , the value of ,
depending on the ratios of the LFV mass elements, can range between zero and
three orders of magnitude above the present bound. We show that the present
bound on rules out a large portion of the CP-violating and the LFV
parameter space which is consistent with the bounds on the LFV rare decays.
We show that studying the correlation between and the P-odd asymmetry
in helps us to derive a more conclusive bound on
We also discuss the possibility of cancelation among the contributions of
different CP-violating phases to .Comment: 35 pages, 9 figure
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