2,159 research outputs found
CP Nonconservation in
CP violation effects in are examined. CP-odd,
-odd and -even observables can both be used to extract information on
the real and imaginary parts of Feynman amplitudes. Two Higgs doublet model
with CP violating phase from neutral Higgs exchange is used to estimate
possible effects.Comment: 9 pages, 4 Figures, Late
Polarized Single Top Production at Leptonic Colliders from Broken R Parity Interactions Incorporating CP Violation
The contribution from the R parity violating interactions in the associated
production of a top quark with a charm antiquark is examined for high energy
leptonic colliders. We concentrate on the reactions associated with the
semileptonic top decay. A set of characteristic dynamical distributions for the
signal events is evaluated and the results contrasted against those from the
standard model W-boson pair production background. Next, we turn to a study of
a CP-odd observable, associated with the top spin, which leads to an asymmetry
in the energy distribution of the emitted charged leptons for the pair of
CP-conjugate final states, and . A
non vanishing asymmetry arises from a CP-odd phase, embedded in the R parity
violating coupling constants, through interference terms between the R parity
violating amplitudes at both the tree and loop levels.Comment: revtex file. 17 pages. 7 postscript figures. 1 table. The revised
version includes an estimate of experimental uncertainties. Submitted to
Phys. Rev.
Weak dipole moment of in collisions with longitudinally polarized electrons
It is pointed out that certain CP-odd momentum correlations in the production
and subsequent decay of tau pairs in collisions get enhanced when the
is longitudinally polarized. Analytic expressions for these correlations
are obtained for the single-pion decay mode of when have
a ``weak" dipole form factor (WDFF) coupling to . For collisions
at the peak, a sensitivity of about 1-5\mbox{ cm} for
the WDFF can be reached using a {\em single} decay
channel, with 's likely to be available at the SLC at Stanford with
polarization of 62\%-75\%.Comment: 9 pages, Latex, PRL-TH-93/17 (Revised
Large Tree Level CP Violation in in The Two Higgs Doublet Model
We find a large CP violation effect within the Two-Higgs-Doublet-Model for
the reaction at future linear colliders. The
CP-asymmetry arises already at the tree level as a result of interference
between diagrams with emission from (and ) and its emission
from a and can be about 10--20\%. In the best case one needs a few
hundred events to observe CP violation at the 3 level.Comment: UU encoded tar compressed tex file with postscript figure
Global Patterns in Marine Sediment Carbon Stocks
To develop more accurate global carbon (C) budgets and to better inform management of human activities in the ocean, we need high-resolution estimates of marine C stocks. Here we quantify global marine sedimentary C stocks at a 1-km resolution, and find that marine sediments store ∼ 3117 (3006–3209) Pg C in the top 1 m (more than twice that of terrestrial soils). Sediments in abyss/basin zones account for 75% of the global marine sediment C stock, and 52% of that stock is within the 200-mile Exclusive Economic Zones of countries. Currently, only ∼2% of sediment C stocks are located in highly to fully protected areas that prevent the disturbance of the seafloor. Our results show that marine sediments represent a large and globally important C sink. However, the lack of protection for marine C stocks makes them highly vulnerable to human disturbances that can lead to their remineralization to CO2, further aggravating climate change impacts
Transverse Tau Polarization in Decays of the Top and Bottom Quarks in the Weinberg Model of CP Non-conservation
We show that the transverse polarization asymmetry of the -lepton in
the decay is extremely sensitive to CP violating
phases arising from the charged Higgs exchange in the Weinberg model of CP
non-conservation. Qualitatively, the polarization asymmetries are enhanced over
rate or energy asymmetries by a factor of . Thus for optimal values of the parameters the method requires top pairs to be observable rather than needed for rate or energy
asymmetries. We also examine polarization in b decays via and find that it can also be very effective in constraining the CP
violation parameters of the extended Higgs sector.Comment: 11,1 figure, SLAC-PUB-608
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