50,916 research outputs found
Emittance increase caused by core depletion in collisions
A new effect is presented, which changes the emittance during colliding-beam
operation in circular colliders. If the initial transverse distribution is
Gaussian, the collision probability is much higher for particles in the core of
the beam than in the tails. When small-amplitude particles are removed, the
remaining ones therefore have a larger transverse emittance. This effect,
called core depletion, may cause a decrease in luminosity. An approximate
analytic model is developed to study the effect and benchmarked against a
multiparticle tracking simulation. Finally, the time evolution of the intensity
and emittances of a Pb bunch in the Large Hadron Collider (LHC) at CERN is
calculated, taking into account also other processes than collisions. The
results show that integrated luminosity drops by 3--4% if core depletion is
taken into account. It is also found that core depletion causes the transverse
emittance to be larger when more experiments are active. This observation could
be checked against experimental data once the LHC is operational.Comment: 20 pages, 5 figure
Electronic libraries and electronic librarians: Who does what in a national electronic community
This talk will have two parts: First, I'm going to describe very briefly what this new kind of library technology is like through a discussion of the Worm Community System (WCS), why it is going to be very important, and why it will involve a lot of money. What I want to emphasize at the start
is that while WCS may seem like an esoteric research project, in fact it is
one of the flagship information projects funded by the National Science
Foundation. In addition, the National Information Infrastructure Act looms
in the immediate future, authorizing an enormous amount of money to be
spent in the development of digital libraries in specialized areas. Digital libraries
will require information systems like WCS. This project has become a national
model of this new kind of information system, but its primary content is really
just a special collection, in the same sense you already know. It is an important
national effort, but there will be lots of other efforts like this in many different
subject areas.
Second, I'm going to discuss in more detail what kinds of people are required
to do this kind of activity. The roles range from traditional librarians all the
way to systems architects. Similarly, the roles range from those that involve
no computer knowledge at all to those that involve very intensive computing.
My expectation is that people who call themselves "librarians" in the foreseeable
future will actually span this entire range, even though now they are significantly
skewed towards the traditional end.published or submitted for publicatio
\u3cem\u3eLegacy of Courage: Calgary’s Own 137th Battalion\u3c/em\u3e by Fred Bagley and Dr. H.D. Duncan [Review]
Review of Fred Bagley & Dr. Harvey Daniel Duncan, A Legacy of Courage: Calgary\u27s Own 137th Overseas Battalion, CEF. Calgary: Pulp Street Books, 1994
TEN COMMANDMENTS FOR AGRICULTURAL ECONOMICS (AND PERHAPS OTHER) ADMINISTRATORS
There is some justification for the impression that agricultural economics has entered an era of relatively greater budget stress than that of the recent past. However, optimal strategies for sustaining or enhancing departmental productivity in research, teaching and extension are invariant to the budget level. These "strategies" are discussed in the form of "ten commandments" to department heads.Teaching/Communication/Extension/Profession,
IRRIGATED AGRICULTURE AND THE GREAT PLAINS: PROBLEMS AND POLICY ALTERNATIVES
Resource /Energy Economics and Policy,
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