11,886 research outputs found
Search for Excited Quarks in at the LHC
If quarks are composite particles, then excited states are expected to play a
r\^ole in the Large Hadron Collider phenomena. Concentrating on virtual
effects, and using a large part of the CMS detection criteria, we present here
a realistic examination of their effect in diphoton production at the LHC. For
various luminosities, we present the 99 % confidence limit (CL) achievable in
parameter space where is the compositeness scale and
M_{q^*} the mass of the state. For a q^* of mass 0.5 TeV, can be excluded at 99% CL with 30 (200) integrated
luminosity.Comment: 11 pages, 11 figure
Management of Potential Fishery Resources
The prevailing situation in the fisheries sector in many
countries of the world can be briefly stated as (1) insufficient
information on fish resources, (2) diminishing stock and (3)
conflicting uses of coastal areas and types of fishing. Since
there is free accessibility to the exploitable resources in the sea,
the natural tendency is to make more and more without regard
to the real availability. The need for fishery management
assumed importance in recent years on account of the uncontrolled,
or rather reckless, exploitation of the resources in
many countries [leading to depletion of stock. Although
according to available information the level of exploitation of
the fishery resources in our country in general is far below the
optimum level, there seems to be too much concentration in,
certain areas and in respect to certain specks which perhaps is a
reflection of the lack of fishery management policies or their
implementation
Rapid plant regeneration from Gerbera jamesonii Bolus callus cultures
A high frequency shoot organogenesis and plant establishment protocol has been developed for Gerbera jamesonii from ex vitro leaf derived callus. The optimal callus was developed on Murashige and Skoog (MS) basal medium supplemented with 0.4 mg L–1 6-benzylaminopurine (BAP), 4.0 mg L–1 -naphthalene acetic acid (NAA) and 3% (w/v) sucrose. Two callus types differing in their structures and growth rates were observed. A friable and non-chlorophyllous callus with high growth rate appeared at the cut surfaces of the explant, and a compact chlorophyllous callus. The rate of shoot bud regeneration was positively correlated with the concentration of growth regulators in the nutrient media.
The explants were highly responsive (83.3%) in a medium containing 2 mg L–1 NAAand 1 mg L–1 BAP after 3 weeks of callus transfer to a medium. Regenerated plantlets were transferred to soil where they grew normally with a survival rate of 95%. This protocol offers
rapid build up of selected clones and opens up prospects for using biotechnological approaches for gerbera improvement
GiRaFFE: An Open-Source General Relativistic Force-Free Electrodynamics Code
We present GiRaFFE, the first open-source general relativistic force-free
electrodynamics (GRFFE) code for dynamical, numerical-relativity generated
spacetimes. GiRaFFE adopts the strategy pioneered by McKinney and modified by
Paschalidis and Shapiro to convert a GR magnetohydrodynamic (GRMHD) code into a
GRFFE code. In short, GiRaFFE exists as a modification of IllinoisGRMHD, a
user-friendly, open-source, dynamical-spacetime GRMHD code. Both GiRaFFE and
IllinoisGRMHD leverage the Einstein Toolkit's highly-scalable infrastructure to
make possible large-scale simulations of magnetized plasmas in strong,
dynamical spacetimes on adaptive-mesh refinement (AMR) grids. We demonstrate
that GiRaFFE passes a large suite of both flat and curved-spacetime code tests
passed by a number of other state-of-the-art GRFFE codes, and is thus ready for
production-scale simulations of GRFFE phenomena of key interest to relativistic
astrophysics.Comment: 23 pages, 4 figures. Consistent with published versio
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