317 research outputs found
A method for determining CP violating phase
A new way of determining the phases of weak amplitudes in charged decays
based on SU(3) symmetry is proposed. The CP violating phase can now be
determined without the previous difficulty associated with electroweak
penguins.Comment: 9 pages plus one figure, Revte
Pain in patients with dementia: A review of pain assessment and treatment challenges
Pain represents a major treatment challenge in older people with dementia. The majority of healthy older people experience regular pain and around 50% take regular analgesics. Pain is likely to be equally prevalent in people with dementia, yet only a small minority are prescribed regular analgesics. This is a key issue since recent work has provided evidence that untreated pain may be a major contributor to reduced quality of life and increases the likelihood of emergence of behavioural and psychological symptoms such as agitation. Better assessment and treatment of pain may therefore substantially improve outcomes for people with dementia. In this context, we reviewed the literature and summarised the best available evidence regarding the frequency of pain and pain diagnosis in patients with dementia based on pain assessment and treatment recommendations for these individuals. Hardly any randomized, controlled studies of pain treatment efficacy in patients with dementia are available, with the consequence that most pain treatment recommendations are not based on the highest level of evidence
Measuring in Decays
We consider the possibility of measuring both and in the KM unitarity triangle using the process . This decay mode has a higher branching fraction (O(1%)) than
the mode . We use the factorization assumption and heavy
hadron chiral perturbation theory to estimate the branching fraction and
polarization. The time dependent rate for can be
used to measure and . Furthermore, examination
of the mass spectrum may be the best way to experimentally find
the broad p-wave meson.Comment: Revtex, 28 pages, 7 figures, title changed, introduction expanded,
added references, details of calculations moved to the appendi
CP Asymmetry In Neutral System At Symmetric Colliders
Contrary to the conventional belief, time integrated asymmetry are measurable
in selected final states in the neutral system at symmetric
colliders. They occur due to the interplay of weak and strong phases of two
different amplitudes in addition to the mixing. Observation of
these asymmetries would be evidence for direct CP violation in the decay
amplitudes.Comment: 10 pages, Revtex; Accepted for publicatin in Phys. Rev. Let
Standard Model Confronting New Results for epsilon'/epsilon
We analyze the CP violating ratio \epe=epsilon'/epsilon in the Standard Model
in view of the new KTeV results. We review the present status of the most
important non-perturbative parameters B_6, B_8, B_K and of the strange quark
mass m_s. We also briefly discuss the issues of final state interactions and
renormalization scheme dependence. Updating the values of the CKM parameters,
of m_t and Lambda (MSbar) and using Gaussian errors for the experimental input
and flat distributions for the theoretical parameters we find \epe
substantially below the NA31 and KTeV data: \epe= (7.7^{+6.0}_{-3.5}) 10^{-4}
and \epe= (5.2^{+4.6}_{-2.7}) 10^{-4} in the NDR and HV renormalization schemes
respectively. A simple scanning of all input parameters gives on the other hand
1.05 10^{-4} < \epe < 28.8 10^{-4} and 0.26 10^{-4} < \epe < 22.0 10^{-4}
respectively. Analyzing the dependence on various parameters we find that only
for extreme values of B_6, B_8 and m_s and suitable values of CKM parameters
and Lambda(MSbar), the ratio \epe can be made consistent with data. We analyze
the impact of these data on the lower bounds for Im(V_{td}V_{ts}^*), Br(K_L to
pi^0 nu barnu), Br(K_L to pi^0e^+e^-)_{dir} and on tan(beta) in the Two Higgs
Doublet Model II.Comment: main latex-file, 4 figures and related latex files, 47 page
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