1,557 research outputs found
Beyond CP violation: hadronic physics at BaBar
I report on recent studies of hadronic physics performed by the BaBar
Collaboration. Emphasis is given to the measurement of the properties of newly
discovered charmed hadrons and to the searches for light and heavy pentaquarks.Comment: 14 pages, 20 postscript figues, contributed to the Proceedings of the
First APS Topical Group Meeting on Hadron Physics, Fermilab, Batavia, IL
(October 24-26, 2004
The 2004 UTfit Collaboration Report on the Status of the Unitarity Triangle in the Standard Model
Using the latest determinations of several theoretical and experimental
parameters, we update the Unitarity Triangle analysis in the Standard Model.
The basic experimental constraints come from the measurements of |V_ub/V_cb|,
Delta M_d, the lower limit on Delta M_s, epsilon_k, and the measurement of the
phase of the B_d - anti B_d mixing amplitude through the time-dependent CP
asymmetry in B^0 to J/psi K^0 decays. In addition, we consider the direct
determination of alpha, gamma, 2 beta + gamma and cos(2 beta) from the
measurements of new CP-violating quantities, recently performed at the B
factories. We also discuss the opportunities offered by improving the precision
of the various physical quantities entering in the determination of the
Unitarity Triangle parameters. The results and the plots presented in this
paper can also be found at http://www.utfit.org, where they are continuously
updated with the newest experimental and theoretical results.Comment: 32 pages, 17 figures. High resolution figures and updates can be
found at http://www.utfit.org v2: misprints correcte
The Pattern of CP Asymmetries in Transitions
New CP violating physics in transitions will modify the CP
asymmetries in B decays into final CP eigenstates (, , , , and ) from their
Standard Model values. In a model independent analysis, the pattern of
deviations can be used to probe which Wilson coefficients get a significant
contribution from the new physics. We demonstrate this idea using several
well-motivated models of new physics, and apply it to current data.Comment: 20 pages, 3 figures, 6 tables. v3: Discussion of higher order
corrections extended; Version appearing in JHE
Flavor SU(3) analysis of charmless B meson decays to two pseudoscalar mesons
Global fits to charmless B --> PP decays in the framework of flavor SU(3)
symmetry are updated and improved without reference to the \sin2\beta measured
from the charmonium decay modes. Fit results directly constrain the
(\bar\rho,\bar\eta) vertex of the unitarity triangle, and are used to predict
the branching ratios and CP asymmetries of all decay modes, including those of
the B_s system. Different schemes of SU(3) breaking in decay amplitude sizes
are analyzed. The major breaking effect between strangeness-conserving and
strangeness-changing decays can be accounted for by including a ratio of decay
constants in tree and color-suppressed amplitudes. The possibility of having a
new physics contribution to K \pi decays is also examined from the data fitting
point of view.Comment: 22 pages and 2 figures; some comments and references added; more
references added, version to appear in journa
Institutional vs. Non-institutional use of Social Media during Emergency Response: A Case of Twitter in 2014 Australian Bush Fire
© 2017, Springer Science+Business Media, LLC. Social media plays a significant role in rapid propagation of information when disasters occur. Among the four phases of disaster management life cycle: prevention, preparedness, response, and recovery, this paper focuses on the use of social media during the response phase. It empirically examines the use of microblogging platforms by Emergency Response Organisations (EROs) during extreme natural events, and distinguishes the use of Twitter by EROs from digital volunteers during a fire hazard occurred in Australia state of Victoria in early February 2014. We analysed 7982 tweets on this event. While traditionally theories such as World System Theory and Institutional Theory focus on the role of powerful institutional information outlets, we found that platforms like Twitter challenge such notion by sharing the power between large institutional (e.g. EROs) and smaller non-institutional players (e.g. digital volunteers) in the dissemination of disaster information. Our results highlight that both large EROs and individual digital volunteers proactively used Twitter to disseminate and distribute fire related information. We also found that the contents of tweets were more informative than directive, and that while the total number of messages posted by top EROs was higher than the non-institutional ones, non-institutions presented a greater number of retweets
Forward-backward and isospin asymmetry for B -> K* l+ l- decay in the standard model and in supersymmetry
We discuss two dedicated observables in exclusive B -> K* l+ l- decay that
can be used to study effects of physics beyond the standard model, namely the
forward-backward asymmetry in the lepton spectrum and the isospin-asymmetry
between decays of charged and neutral B mesons. We consider the region of large
recoil-energy (i.e. small invariant mass of the lepton pair), and employ the
QCD factorization approach to exclusive B meson decays. Sub-leading effects in
the heavy quark mass expansion have been taken into account for the calculation
of the isospin-asymmetry. We give predictions for decay asymmetries in the
standard model, and its supersymmetric extension with minimal flavor violation,
using parameter values allowed by current experimental constraints on B->X_s
gamma decay.Comment: 21 pages, LaTeX with 6 figures, added reference
Characterization of the use of social media in natural disasters: A systematic review
© 2014 IEEE. Social media sites are playing a significant role in rapid propagation of information when disasters occur. This effective communication platform is a great useful tool for emergency (disaster) management agencies during all phases of disaster management life cycle: prevention (mitigation), preparedness, response, and recovery. This study has conducted a systematic review of social media use in disaster management literature to identify how social media sites have been used during these four critical phases of disaster management life cycle in order to recommend strategies for government officials. A systematic method has been used to search four major academic databases for this review. The search resulted in 40 articles and categorized the findings in six main themes: situational awareness, data collection methods, distributed sensor systems, news and rumors, sentiment analysis, and digital volunteerism
Using goals to model strategy map for business IT alignment
Strategy Map (SM) is one of the widely used methods to create business aligned IT strategy map providing valuable insights to business executives. However, problem with strategy map method is that it is not easy to use which can lend itself to various interpretations. This is because linkages between the strategic objectives in the four strategy map perspectives are not explicit which makes SM ambiguous. Goal modelling approaches from Requirements Engineering (RE) have proven rigorous in elicitation and representation of information system requirements. In an attempt to make explicit the causal relationships of SM linkages meaningful this research proposes the use of goal modelling approach i*
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