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	Spallation - Wikipedia, the free encyclopedia
		In nuclear physics, spallation is the process in which a heavy nucleus emits a large number of nucleons as a result of being hit by a high-energy proton, thus greatly reducing its atomic weight.
		Spallation occurs naturally in earth's atmosphere owing to the impacts of cosmic rays, and also on the surfaces of bodies in space such as meteorites and the moon.
		Spallation is one of the processes by which a particle accelerator may be used to produce a beam of neutrons.
	en.wikipedia.org /wiki/Spallation (221 words)

	Spallation -- Facts, Info, and Encyclopedia article (Site not responding. Last check: 2007-09-07)
		Evidence of cosmic ray spallation is evidence that the material in question has been exposed on the surface of the body of which it is part, and gives a means of measuring the length of time of exposure.
		Spallation is one of the processes by which a (A scientific instrument that increases the kinetic energy of charged particles) particle accelerator may be used to produce a beam of (An elementary particle with 0 charge and mass about equal to a proton; enters into the structure of the atomic nucleus) neutrons.
		A (A heavy silvery toxic univalent and bivalent metallic element; the only metal that is liquid at ordinary temperatures) mercury target is used, and 20 to 30 neutrons are expelled after each impact.
	www.absoluteastronomy.com /encyclopedia/s/sp/spallation.htm (123 words)

	Spallation (Site not responding. Last check: 2007-09-07)
		Spallation refers to nuclear reactions that occur when energetic subatomic particles (such as protons in an accelerator beam) strike or interact with the nucleus of an atom (such as in a target) in which many particles, including many neutrons, are ejected from the nucleus.
		For spallation, the corresponding number is about 20 MeV for an infinite lead target bombarded by 1000-MeV protons (this value depends on the target material and the size of the target).
		Finally, spallation neutrons have higher energies than fission neutrons, requiring well-designed shielding to prevent high-energy neutrons from escaping the spallation source environment.
	www.lansce.lanl.gov /resources/spallation.html (935 words)

	Penn State Eberly College of Science -- Sokol Spearheading Portion of Spallation Neutron Source Research Facility
		The Spallation Neutron Source is one of the largest construction projects of a scientific facility that the United States has undertaken in several decades.
		The Spallation Neutron Source is an accelerator-based neutron source that will provide the most intense pulsed neutron beams in the world for scientific research and industrial development.
		The Spallation Nuclear Source facility, currently the second biggest science project in the world with a price tag of $1.4 billion, is being built by six national laboratories on an 80-acre site at the Oak Ridge National Laboratory in Tennessee.
	www.science.psu.edu /alert/Sokol4-2003.htm (1464 words)

	Spallation Neutron Source - Wikipedia, the free encyclopedia
		The Spallation Neutron Source (SNS) is an accelerator-based neutron source being built in Oak Ridge, Tennessee, USA, by the U.S. Department of Energy (DOE).
		SNS is being designed and constructed by a unique partnership of six DOE national laboratories: Argonne, Lawrence Berkeley, Brookhaven, Jefferson, Los Alamos, and Oak Ridge.
		When a high-energy proton bombards a heavy atomic nucleus, some neutrons are "spalled," or knocked out, in a nuclear reaction process called spallation.
	en.wikipedia.org /wiki/Spallation_Neutron_Source (598 words)

	Spallation: What and Why (Site not responding. Last check: 2007-09-07)
		Corresponding pulses of neutrons freed by the spallation process will be slowed down in a moderator and guided through beam lines to areas containing special instruments such as neutron detectors.
		Furthermore, unlike the usual situation at a continuous neutron source, it is not required that the neutron detectors move during an experiment, making it easy to arrange large detector arrays or multidetectors around the sample.
		Since then, an ongoing series of meetings and workshops has been held to involve the scientific user community in establishing performance requirements for the SNS and in selecting the suite of instruments to be built as part of the project.
	www.sns.gov /aboutsns/what-why.htm (878 words)

	Neutrons Spill Secrets
		It is the home of the $1.4 billion Spallation Neutron Source, a rather unglamorous name for one of the most ambitious -- and, if you ask the researchers involved, promising -- science projects ever assembled on U.S. ground.
		Spallation reactions produce neutrons in all kinds of energetic states.
		A similar spallation source is in the works in Japan, and a proposed spallation source in Europe is in "a holding pattern," he says.
	whyfiles.org /shorties/142spallation_neutron (1741 words)

	Announcement: Workshop on Neutron Detectors for Spallation Sources (Site not responding. Last check: 2007-09-07)
		Workshop on Neutron Detectors for Spallation Sources Brookhaven National Laboratory, Upton, New York 11973 September 24-26, 1998 http://neutronworkshop.bnl.gov The purpose of this workshop is to bring together neutron researchers with special interest in detector instrumentation and experimental needs.
		The Spallation Neutron Source (SNS) in America is now in the planning and design stage.
		The Japanese Hadron Facility is under consideration for funding and the European Spallation Source (ESS) is the next major planned neutron facility in Europe.
	www.neutron.anl.gov /pipermail/neutron/1998/000188.html (315 words)

	NEJM -- Spallation and migration of silicone from blood-pump tubing in patients on hemodialysis
		NEJM -- Spallation and migration of silicone from blood-pump tubing in patients on hemodialysis
		Spallation and migration of silicone from blood-pump tubing in patients on hemodialysis
		Spalled particles of silicone were observed in the livers of patients with chronic renal failure treated by hemodialysis.
	content.nejm.org /cgi/content/short/306/3/135 (221 words)

	Abstracts
		The mechanisms of photomechanical spallation are investigated in a large-scale MD simulation of laser interaction with a molecular target performed in the irradiation regime of the inertial stress confinement.
		Two stages can be identified in the evolution of voids in laser spallation, the initial void nucleation and growth, with the number of voids of all sizes increasing, followed by void coarsening and coalescence, when the number of large voids increases at the expense of quickly decreasing population of small voids.
		As the size of the film increases, the location of the spallation region and the region of the maximum tensile stresses are splitting apart and the threshold fluence for spallation increases.
	www.people.virginia.edu /~lz2n/Abstracts.html (10747 words)

	PACS, Spallation (Site not responding. Last check: 2007-09-07)
		The PACS group is strongly involved in investigations on spallation reactions, inside an international collaboration of nuclear physicists between IPN d'Orsay, GSI (Darmstadt, Germany), SPhN (Service de Physique Nucléaire, CEA Saclay), Universitad de Santiago de Compostella (Spain), and CENBG (Centre d'étude de Bordeaux-Gradignan).
		Spallation residues influence the chemical and radiotoxical properties of the spallation target situated within the nuclear core.
		The FRagment Separator at GSI gives a unique possibility to study in details the isotopic distribution of spallation residues using the inverse kinematics methods with a target of liquid hydrogen or deuteron.
	ipnweb.in2p3.fr /%7epacs/activites/spallation/spallationa.html (421 words)

	The Spallation Process (Site not responding. Last check: 2007-09-07)
		In the first stage of the spallation process, called the ãintranuclear cascadeä phase, a high-energy particle interacts with an individual nucleon inside the nucleus.
		In the second stage of the spallation process, the highly-excited nucleus relaxes by ãevaporatingä nucleons or small clusters of nucleons.
		The probability of producing a particular spallation product depends on the incident particle type (e.g., neutron, proton, or pion) and energy, and on the atomic number and mass of the target nucleus.
	apt.lanl.gov /pitcher/tsld003.htm (149 words)

	Cover Story: Understanding Metal-Failure Dynamics (Site not responding. Last check: 2007-09-07)
		Because a detailed model of spall fracture is lacking, the microstructural origins of dynamic fracture in ductile metals are being studied by physicist Jim Belak to obtain a better understanding of beginning damage from spallation, the scab that forms near the metal surface during high-explosive detonations.
		While this is a "first-cut" model based on limited data, it is a major step along the way toward developing an accurate and robust simulation capability for recompressed damaged materials for stockpile stewardship.
		The images are from a 6-mm region in the center of the spall plane in single-crystal aluminum (a) and polycrystalline aluminum (b).
	www.industrialheating.com /CDA/ArticleInformation/coverstory/BNPCoverStoryItem/0,2830,87437,00.html (3198 words)

	Neutron Sources - Spallation Source
		Neutrons cannot only be produced "softly" with thermal neutrons by fission of heavy nuclei (reactor), but also with "brute" force by a cleavage reaction (spallation).
		The spectrum of the neutrons emittied by spallation is very similar to a fission spectrum.
		Therefore, like in a reactor, water can be used to slow down the neutrons in a realtively small volume to thermal energy to obtain a neutron source.
	www.physik.uni-kiel.de /kfn/infos/Neutronenquellen/spallation-engl.php (258 words)

	Animations from a Molecular Dynamics Simulation of Laser Spallation (Site not responding. Last check: 2007-09-07)
		Animated sequences of snapshots from a simulation of laser spallation: void nucleation, growth, coarsening, coalescence and percolation is induced by laser irradiation in the regime of stress confinement.
		In the molecular-level images (left frame) molecules are shown by dots that are smaller than their actual size so that the largest voids (or regions of reduced density) could be identified while looking through the 40 nm deep computational cell.
		A detailed discussion of this and other simulations of laser spallation of molecular and metal targets is given in
	www.faculty.virginia.edu /CompMat/spallation/animations/index.html (210 words)

	Spallation Neutron Source Front-End
		A startup negative hydrogen ion source and low-energy beam transport (LEBT) system, the first two components of the SNS "front-end system," have been built and are now undergoing commissioning tests.
		This is necessary to allow the extraction-kicker magnet in the SNS accumulator ring to rise to its full strength.
		At that point, the accumulated beam can then be directed towards the spallation target without spilling the high energy ions on the vacuum chamber.
	www.lbl.gov /Science-Articles/Archive/SNS-front-end.html (1006 words)

	Example of Isotopes Produced by Spallation (Site not responding. Last check: 2007-09-07)
		Niobium is monoisotopic with an atomic mass of 93.
		Note that neutron-poor spallation products, which lie to the left of the line of stability, are more proabable than neutron-rich products.
		However, this figure shows that it is possible to produce neutron-rich isotopes via spallation, as well.
	apt.lanl.gov /pitcher/sld004.htm (128 words)

	ASQ Home Page Template
		Below the spallation neutron source of the SINQ-target station, the proton beam is diverted by bending magnets vertically upwards from underneath into the heavy metal target.
		The target is situated in the center tube of the heavy water moderator tank.
		high energy spallation neutrons per second, which are slowed down to thermal energy in the moderator.
	asq.web.psi.ch /ASQ/facilities/SINQSYSTEMS.html (1289 words)

	The Front End of the Spallation Neutron Source: Berkeley Lab sets the pace
		Faced with a deadline less than four months away, scientists and engineers with the Lawrence Berkeley National Laboratory cleared a major hurdle for completing their part of the Spallation Neutron Source (SNS), the accelerator-based facility that will provide the most intense pulsed-beams of neutrons ever available for scientific research and industrial development.
		On Friday, January 25, at around 4:30 p.m., they drew the first ion beam out of the radio-frequency quadrupole (RFQ) accelerator, which is the third and perhaps most technically challenging of the four components in the SNS front-end system.
		With Oak Ridge National Laboratory, where the Spallation Neutron Source is located, Argonne, Berkeley, Brookhaven, Jefferson, and Los Alamos national laboratories are building the facility's major components.
	www.lbl.gov /Science-Articles/Archive/AFRD-SNS-frontend.html (1332 words)

	Newswise
		With the recent "warm commissioning" of its linear accelerator, Oak Ridge National Laboratory's Spallation Neutron Source (SNS) has passed a crucial test and milestone on its way to completion in 2006.
		Newswise — With the recent "warm commissioning" of its linear accelerator, Oak Ridge National Laboratory's Spallation Neutron Source (SNS) has passed a crucial test and milestone on its way to completion in 2006.
		The SNS's linear accelerator, or linac, is composed of two sections: the "warm," or room temperature section, and a superconducting section that operates at temperatures hundreds of degrees below zero.
	www.newswise.com /articles/view/507260 (702 words)

	Synchrotron-Driven Spallation Sources - Bryant (ResearchIndex) (Site not responding. Last check: 2007-09-07)
		Abstract: INTRODUCTION The use of synchrotrons for pulsed neutron spallation sources is an example of spin-off from the accelerator development prompted by particle physics.
		The first proposal for an accelerator-driven source with a thermalised neutron facility was in the 1960s (Intense Neutron Generator, ING) [1], but this project was never built.
		There was earlier work on 'electrical' breeders [2] and the direct bombardment of a heavy-metal target for spallation had already been foreseen by Lewis [3],...
	citeseer.ist.psu.edu /255913.html (463 words)

	News archive - Yorkshire European Spallation Source
		To have the European Spallation Source in the UK would be a major coup and would ensure that Europe maintains its lead in this important area of science.
		The delegation visited the group at KEK, the Japanese High Energy Physics laboratory, which is developing FFAG accelerator technology, to learn more about the techniques involved, and to kick start a collaboration between the KEK group and White Rose.
		Martin and Christine also visited the construction site of the new J-PARC facility at Tokai, which will be the location for Japan’s next generation spallation neutron source, similar to the US facility which is under construction at Oak Ridge Tennessee.
	www.yorkshire-ess.org.uk /news_items_2004.htm (1489 words)

	MATERIALS FOR SPALLATION NEUTRON SOURCES: II: Radiation Effects, B
		Specimens irradiated in operating medium-power spallation devices are at present the only source of direct information on the behavior of materials in a spallation environment.
		Ferritic/martensitic steels in the target structure of a spallation neutron source will experience many of the extreme conditions expected in a fusion power plant (i.e., high-energy neutrons that produce large amounts of displacement damage and transmutation helium).
		Linacs are proposed for spallation neutron sources which are capable of relatively high beam currents.
	www.tms.org /Meetings/Annual-97/Program/Sessions/TAS4.html (1210 words)

	spallation - StormingMedia
		Spallation with High Energy Protons as a Source of 178m2Hf Isomers: Optimization and Accumulation Date: 07 SEP 2001
		Spallation and Dynamic Fracture as an Effect of Laser Induced Shock Waves in Carbon Based Composite Materials Date: OCT 89
		Spallation and Dynamic Fracture as an Effect of Laser Induced Shock- Waves Date: 02 JAN 88
	www.stormingmedia.us /keywords/spallation.html (1406 words)

	ESS project - Yorkshire European Spallation Source
		This site provides information about the Yorkshire bid to host the European Spallation Source (ESS) in the region, and the organisations working to secure it.
		The ESS is a £1 billion scientific research and development facility - a ‘next generation neutron source’ - the plans for which have been developed by hundreds of European scientists for over a decade.
		It will provide researchers from all scientific disciplines the opportunity to look deep inside matter to understand the behaviour of individual atoms and molecules.
	www.yorkshire-ess.org.uk (98 words)

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