12,052 research outputs found
Aquaculture in tropical Mexican lakes and dams: achievements and perspectives
Mexico, with highly diverse physiography, geology, soils and climate, is a country with a broad mosaic of aquatic ecosystems within 320 watersheds. This paper presents a brief picture of Mexican fresh waters, the distribution of rainfall and the potential for aquaculture. The main fish species and water bodies, dams and lakes, are highlighted. The country faces problems of surface water shortage which requires better management
Non-standard semileptonic hyperon decays
We investigate the discovery potential of semileptonic hyperon decays in
terms of searches of new physics at teraelectronvolt scales. These decays are
controlled by a small -flavor breaking parameter that allows for
systematic expansions and accurate predictions in terms of a reduced dependence
on hadronic form factors. We find that muonic modes are very sensitive to
non-standard scalar and tensor contributions and demonstrate that these could
provide a powerful synergy with direct searches of new physics at the LHC.Comment: v2. Comparison with direct searches of new physics at the LHC
presente
decay anomalies from nonabelian local horizontal symmetry
Recent anomalies in meson decays are consistent with
exchange of a heavy vector boson. Here we try to connect such new physics
to understanding the origin of flavor, by gauging generation number.
Phenomenological and theoretical considerations suggest that the smallest
viable flavor symmetry (not including any extra U(1) factors) is chiral , which acts only on generation indices and does
not distinguish between quarks and leptons. Spontaneous breaking of the
symmetry gives rise to the standard model Yukawa matrices, and masses for the
16 -like gauge bosons, one of which is presumed to be light enough to
explain the anomalies. We perform a bottom-up study of
this framework, showing that it is highly constrained by LHC dilepton searches,
meson mixing, decays and CKM unitarity. Similar anomalies are predicted for
semileptonic decays of to lighter mesons, with excesses in the
channels and deficits in , but no deviation in .
The lightest mass is TeV if the gauge coupling is .Comment: 13 pages, 4 figures; v2: minor corrections and improvements,
references added; v3: corrected fig.1, published versio
New Physics in : Interplay between semileptonic kaon and hyperon decays
We review a novel model-independent approach to the analysis of new-physics
effects in the transitions. We apply it to (semi)leptonic
kaon decays and study their complementarity with pion and hyperon
decays or with collider searches of new physics.Comment: Contribution to the NA62 Physics Handbook. It summarizes the analysis
presented in arXiv:1605.07114 and discusses in more detail the interplay
between and semileptonic hyperon decays as new-physics probe
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