28 research outputs found
New Constraints (and Motivations) for Abelian Gauge Bosons in the MeV-TeV Mass Range
We survey the phenomenological constraints on abelian gauge bosons having
masses in the MeV to multi-GeV mass range (using precision electroweak
measurements, neutrino-electron and neutrino-nucleon scattering, electron and
muon anomalous magnetic moments, upsilon decay, beam dump experiments, atomic
parity violation, low-energy neutron scattering and primordial
nucleosynthesis). We compute their implications for the three parameters that
in general describe the low-energy properties of such bosons: their mass and
their two possible types of dimensionless couplings (direct couplings to
ordinary fermions and kinetic mixing with Standard Model hypercharge). We argue
that gauge bosons with very small couplings to ordinary fermions in this mass
range are natural in string compactifications and are likely to be generic in
theories for which the gravity scale is systematically smaller than the Planck
mass - such as in extra-dimensional models - because of the necessity to
suppress proton decay. Furthermore, because its couplings are weak, in the
low-energy theory relevant to experiments at and below TeV scales the charge
gauged by the new boson can appear to be broken, both by classical effects and
by anomalies. In particular, if the new gauge charge appears to be anomalous,
anomaly cancellation does not also require the introduction of new light
fermions in the low-energy theory. Furthermore, the charge can appear to be
conserved in the low-energy theory, despite the corresponding gauge boson
having a mass. Our results reduce to those of other authors in the special
cases where there is no kinetic mixing or there is no direct coupling to
ordinary fermions, such as for recently proposed dark-matter scenarios.Comment: 49 pages + appendix, 21 figures. This is the final version which
appears in JHE
Two-Body B Meson Decays to and -- Observation of {'}K$
In a sample of 6.6 million produced B mesons we have observed decays B ->
eta' K, with branching fractions BR(B+ -> eta' K+ = 6.5 +1.5 -1.4 +- 0.9) x
and BR(B0 -> eta' K0 = 4.7 +2.7 -2.0 +- 0.9) x . We have
searched with comparable sensitivity for 17 related decays to final states
containing an eta or eta' meson accompanied by a single particle or low-lying
resonance. Our upper limits for these constrain theoretical interpretations of
the B -> eta' K signal.Comment: 12 page postscript file, postscript file also available through
http://w4.lns.cornell.edu/public/CLN
Attorneys' Questions and Children's Productivity in Child Sexual Abuse Criminal Trials
Summary: We investigated the links between questions child witnesses are asked in court, children’s answers, and case outcome. Samples of acquittals and convictions were matched on child age, victim–defendant relationship, and allegation count and severity. Transcripts were coded for question types, including a previously under-examined type of potentially suggestive question, declarative questions. Children’s productivity was conceptualized in a novel way by separating new from repeated content and by adjusting the definition based on the linguistic demands of the questions. Attorneys frequently used declarative questions, and disconcertingly, attorneys who used these and other suggestive questions more frequently were more likely to win their case. Open-ended and closed-ended questions elicited similar levels of productivity from children, and both elicited more productivity compared with suggestive questions. Results highlight how conceptualization of questions and answers can influence conclusions, and demonstrate the important real-world implications of attorney questioning strategies on legal cases with child witnesses Copyright © 2014 John Wiley & Sons, Ltd. Legal cases involving alleged child sexual abuse have received massive media coverage in the USA and abroad over the last several decades (see, e.g., Britton, 2004; Commonwealth v. Sandusky in Drape, 2012; Levs & Dolan, 2012; Paulson, 2002; State v. Buckey, 1990). This attentio