17,009 research outputs found
Experiences in wetland co-management: the MACH project
Wetlands, Fishery management
A Mass Formula from Light to Hypernuclei
Simultaneous description of ordinary and hypernuclei masses by a single mass
formula has been a great challenge in nuclear physics. Hyperon-separation
energies of about forty Lambda(), three
Lambda-Lambda(), one Sigma() and seven Cascade()
hypernuclei have been experimentally found. Many of these nuclei are of light
masses. We prescribe a new mass formula, called BWMH, which describes the
normal and hypernuclei on the same footing. It is based on the
modified-Bethe-Weizs\"acker mass formula (BWM). BWM is basically an extension
of the Bethe-Weizs\"acker mass formula (BW) for light nuclei. The parameters of
BWM were optimized by fitting about 3000 normal nuclei available recently. The
original Bethe-Weizs\"acker mass formula (BW) was designed for medium and heavy
mass nuclei and it fails for light nuclei. Two earlier works on hypernuclei
based on this BW show some limitations. The BWMH gives improved agreement with
the experimental data for the line of stability, one-neutron separation energy
versus neutron number spectra of normal nuclei, and the hyperon-separation
energies from hypernuclei. The drip lines are modified for addition of a
hyperon in a normal nucleus.Comment: Presented at the "XXIX Mazurian Lakes Conference on Physics: Nuclear
Physics and the Fundamental Processes, Piaski, Poland, August 30 - September
6, 2005." (7 pages, 1 Table, 1 Figure
Deterrence, preemption and panic: A Common-enemy problem of terrorism
We develop a game-theoretic analysis of terrorism that examines the interaction between a terrorist organization and multiple target countries, and considers both pre-emption and deterrence as counterterrorist policies. The damage from terror includes not only the material cost of fatality, injury and loss of property, but also the resultant fear. The fear-effect leads to different kinds of equilibria and implications for counter-terrorism policies. In particular, the model identifies conditions under which greater pre-emption may be the rational response to an increase in terrorism, i.e., it analyzes the merit of the dictum: "offense is the best defense." Further, it examines the characteristics of cooperative behavior among target countries in dealing with the threat of terrorism.Terrorism; Preemption; Panic; Deterrence; Cooperation; Target Countries
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