The International Committee on Future Accelerators periodically publishes "newsletters" with a theme. The most recent newsletter is on the subject given above. It may be obtained at
The theme is "Accelerator Driven Sub-Critical Assemblies (ADS) and its challenge to accelerators." This is a topic that could have a deep impact on the future of our society. As we all know, developing clean energy and protecting the environment are two top priorities in countries around the world. ADS is an accelerator-based technology that may provide a viable solution to these major problems. Jiuqing collected 6 excellent articles in the theme section. They give a comprehensive review of this important accelerator field, including valuable lessons learned from the past.
Estimated content 55,000 tons uranium per UPI. The second suggests ~40,000 tonnes of uranium, ~40 million tonnes of 0.1% ore. If the 0.1% ore is itself the usual 0.7% U235, then ~10,000 tonnes of 3% enriched would net from the ore body.
As preparation for the PET scan you were given an injection with a radioactive tracer which decays via positron emission. The PET scanner doesn't generate any radiation, it simply detects the 511 keV gamma rays produced when the positrons in the tracer annihilate with an electron.
There are three objects with higher probability of impact on the list, two of them much larger than Apophis (270 m diameter). Their diameters are 560 m and 780 m.
Agent of Vega or another one of the James Schmitz selections Crown of Slaves - David Weber (Harrington universe) - long Mother of Demons - Eric Flint Mountains of Morning - Lois McMaster Bujold Oath of Swords - David Weber fantasy Pandora's Legion - Christopher Anvil Sleipnir - Linda Evans A Logic Named Joe - Murray Leinster Starliner - David Drake
An industry which could create a few hundred thousand jobs, transmute existing long-lived nuclear waste to short-lived stuff, generate power with minimum CO2, etc. Total R&D cost, including prototype at full commercial scale, under $10B. A proton accelerator with ten times the power and same energy as the Spallation Neutron Source in Oak Ridge can be used to drive a sub-critical nuclear power system or to transmute existing nuclear waste or both. There is basic R&D and a lot of engineering needed. R&D and prototype cost would be less than ITER, the International Tokamak Experimental Reactor (fusion). Lots of messy politics because of concern about nuclear weapons proliferation, however. And NIMBY. No chance of an uncontrolled reaction, since turning off the proton beam stops the reaction in under a microsecond (speed of light from source to target).
Charles D. Bowman The ADNA Corporation, Accelerator-Driven Neutron Applications, Los Alamos, New Mexico 87544; e-mail: cbowman@roadrunner.com
Abstract The renewed interest since 1990 in accelerator-driven subcritical systems for transmutation of commercial nuclear waste has evolved to focus on the issue of whether fast- or thermal-spectrum systems offer greater promise. This review addresses the issue by comparing the performance of the more completely developed thermal- and fast-spectrum designs. Substantial design information is included to allow an assessment of the viability of the systems compared. The performance criteria considered most important are (a) the rapidity of reduction of the current inventory of plutonium and minor actinide from commercial spent fuel, (b) the cost, and (c) the complexity. The liquid-fueled thermal spectrum appears to offer major advantages over the solid-fueled fast-spectrum system, making waste reduction possible with about half the capital requirement on a substantially shorter time scale and with smaller separations requirements.
There are ~14000 employees at LANL. I'd guess 20,000 laptop and desktop machines. 0.1% loss per year isn't bad. There's nothing in the article to say when the other 67 might have fallen off the radar.
In deep water submersibles the occupied portion is a sphere to best resist pressure. The rest of the craft is filled with water at ambient pressure. The drawing in the article shows this one to follow that pattern. Your first comment is refuted.
The Trieste was a tethered bathyscape. It went down on a cable and back up again. No ability to survey an area. I'd like to survey deep trenches as possible nuclear waste sites. Put the stuff in wedge shapped containers and drop it into deep muck at the bottom of such trenches. If it's 20m down in muck under 7-11 km of water it's going to be easier to produce new nuclear material than to retrieve
The land area of the Earth has been the subject of intense exploration for millenia yet we're still learning about it. Satellites, a 50 year old vehicle for exploration, have helped immensely. Why do you think a new undersea vehicle will not have a similar effect on ocean exploration?
I ran a magnetic finite element job using a commercial code on Windows XP (company required for this code) which used 15.5 GB of RAM (16 available) and 11 GB of swap. It took five days to run and I couldn't do anything else with the PC, but that's OK - I have an RHEL 5 box next to it.
We had a 20 year old, 5MW transformer go a month ago. Internal bolted connections had loosened in the years since we had last drained the oil to inspect them. There was internal arcing which damaged the connections so badly they had to be replaced. The transformer was drained of oil and shipped off for repair. It was re-installed this week.
We have a vendor sample the oil annually to check for compounds formed during arcing. The oil check picked up the nascent problem about five months ago. We didn't repair it then because the accelerator was operating. When the accelerator was shut down for the summer (electricity price hike) the oil was drained and the problem found to require offsite repair.
We don't have the money to stock spare transformers. CERN seems to. Or at least they have the cash to buy a spare fast and repair the broken one at leisure.
If Fermilab had handled the public relations better before the SSC site decision, the locals might not have opposed it, sending it to Texas. Had the Tevatron been used as the injector for the SSC, as the CERN complex does for the LHC, the cost would have been much less. The SSC might have been running for a decade in this scenario.
Fermilab set up a local committee to discuss the possible siting of the International Linear Collider, a proposed follow-on to LHC which will cost about the same. The lab learned from the SSC mistake. The ILC would be 30-50 miles long but the most complicated stuff, including the detectors, would fit on the Fermilab site of ~6400 acres. The rest goes in a couple of long, deep tunnels.
The magnets use NbTi (niobium titanium) alloy superconductor which has a critical temperature of ~9K. Current capability of a superconductor is a function of the local magnetic field and the temperature. The greater the ratio of critical temperature (9K) to operating temperature, the greater the current that can be carried. 9/4.5=2 while 9/2 =4.5. It's not linear, but one can get to higher fields at the lower temperature, and therefore greater beam energies in the same tunnel. The Tevatron operates at 4.5K, BTW.
The DOE Office of Science has multiples sub-offices, including Fusion, Basic Energy Sciences, High Energy Physics and Nuclear Physics.
Fusion: The 2008 Omnibus spending bill cut all US funding for ITER, the International Tokamak Experimental Reactor.
Basic Energy Sciences: mostly funds small university groups and the accelerator "light sources" and particle sources those groups use. It didn't suffer too badly. Most of SLAC's funding now comes from BES. There are still some groups at SLAC working on high energy physics in connection with Fermilab and CERN (LHC).
High Energy Physics - Fermilab is the only high energy physics lab left in the US. As was mentioned above, the last high energy experiment at SLAC was shut down prematurely as a result of the 2008 budget. The Tevatron at Fermilab will be shut down at the end of either FY09 or FY10, depending on budgets and the progress of LHC.
Nuclear Physics - Funds the CEBAF accelerator at Jefferson Lab, the RHIC accelerator at Brookhaven, and the university groups which do research at either. These people look at nuclei - how they hang together, how the particles within each proton or neutron behave in a nucleus rather than when they're all "alone" as in a high energy experiment, etc.
If I had $20K for a really big workstation
on
DDR3 RAM Explained
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· Score: 1
I run large electromagnetic finite element problems on a machine with 16GB of DDR2 with two Xeon Dual Cores at 2.66 GHz on XP64. One job takes about four days. I can run two in parallel before memory gives out. If my firm had $20K available I'd get a machine with 64GB of DDR3 at "1600 MHz" and dual quad-core at 3.2GHz. I could run larger jobs or more in parallel and they might take only three days - two iterations per week.
The first day will likely be spent in paperwork and safety briefings. One of the key things you should be told is "bio-safety level". Depending on location and age (over 18 or not) you may be restricted as to the level of organisms you can deal with.
-----
Most important trait: Ask questions. Ask dumb questions. Ask questions even if you feel embarrassed not knowing the answer. You don't want to hurt yourself or a colleague by guessing. Nor does your employer want you to screw up an experiment by guessing, but that's secondary to safety.
Getting a first draft, however bad, out for review is critical. There are few people comfortable writing first drafts of procedures. Everyone literate is willing to comment and suggest improvements. I like http://www.atlassian.com/software/jira/ as a vehicle for organizing input, if you have the money. twiki.org is also used here.
pulse length is ~10 fs or 3 microns at the speed of light. Since most of the stuff one looks at is at thermal velocities, this is certainly a macroscopic freeze frame. To look at steps of chemical reactions, sub-femtosecond pulses are desirable. Google "energy recovery linac" (ERL) for information on a mechanism for getting such short pulses. UK was hoping to build an ERL-based light source at Daresbury but the budget news out today http://physicsworld.com/cws/article/news/32163 suggests this won't go ahead for a while.
There are about 700 million air trips per year. I estimate that the unnecessarily increased screening is 1 hour each versus pre-9/11. 8760 hours/year, so 79,909 years. At 80 years/life, about 1000 lives. If you assume the average passenger has lived half his/her life, 2000 lives per year.
Why "unnecessarily increased"? Increased screening for weapons is not needed due to strengthened crew doors. Shoe removal for everyone is not justified by one idiot who couldn't get the fuse to light - the ban on matches and cigarette lighters suffices. Ditto ban on liquids due to the incident in Britain in which their authorities later admitted the stuff couldn't have been mixed into an explosive in the air.
Explosives in checked and carry-on luggage like Lockerbie, a real concern, still aren't covered by sniffers at many airports.
What wouldn't be theatre? Carry-on and checked luggage through x-ray and explosives sniffer. Person through metal detector and explosives sniffer. No random checks. No shoe removal.
If the US lost four or fewer planes a year to in-sky explosions without significant ground damage the rest of us would come out ahead.
It seems strange that they didn't aim for the retro-reflector placed by one of the Apollo missions which has been used for 30+ years for laser ranging experiments. It's location is well known. That would give them a real 800,000 km beam path, roughly half of what they claimed.
Slashdot Mirror
The International Committee on Future Accelerators periodically publishes "newsletters" with a theme. The most recent newsletter is on the subject given above. It may be obtained at
http://www-bd.fnal.gov/icfabd/
The theme is "Accelerator Driven Sub-Critical Assemblies (ADS) and its challenge to accelerators." This is a topic that could have a deep impact on the future of our society. As we all know, developing clean energy and protecting the environment are two top priorities in countries around the world. ADS is an accelerator-based technology that may provide a viable solution to these major problems. Jiuqing collected 6 excellent articles in the theme section. They give a comprehensive review of this important accelerator field, including valuable lessons learned from the past.
Virginia land hides huge uranium deposit
First URL is UPI story. Second is abstract of a scholarly paper from Virginia Tech.
http://www.upi.com/Top_News/2008/01/02/Virginia-land-hides-huge-uranium-deposit/UPI-69751199296526/
http://www.geoinformatics.vt.edu/server/docs/jjerden/NA99l.htm
Estimated content 55,000 tons uranium per UPI. The second suggests ~40,000 tonnes of uranium, ~40 million tonnes of 0.1% ore. If the 0.1% ore is itself the usual 0.7% U235, then ~10,000 tonnes of 3% enriched would net from the ore body.
As preparation for the PET scan you were given an injection with a radioactive tracer which decays via positron emission. The PET scanner doesn't generate any radiation, it simply detects the 511 keV gamma rays produced when the positrons in the tracer annihilate with an electron.
There are three objects with higher probability of impact on the list, two of them much larger than Apophis (270 m diameter). Their diameters are 560 m and 780 m.
http://neo.jpl.nasa.gov/risk/
Scroll down to "Objects not recently observed"
http://www.baen.com/library/defaultTitles.htm/ to save the students money
Agent of Vega or another one of the James Schmitz selections
Crown of Slaves - David Weber (Harrington universe) - long
Mother of Demons - Eric Flint
Mountains of Morning - Lois McMaster Bujold
Oath of Swords - David Weber fantasy
Pandora's Legion - Christopher Anvil
Sleipnir - Linda Evans
A Logic Named Joe - Murray Leinster
Starliner - David Drake
and many others
An industry which could create a few hundred thousand jobs, transmute existing long-lived nuclear waste to short-lived stuff, generate power with minimum CO2, etc. Total R&D cost, including prototype at full commercial scale, under $10B. A proton accelerator with ten times the power and same energy as the Spallation Neutron Source in Oak Ridge can be used to drive a sub-critical nuclear power system or to transmute existing nuclear waste or both. There is basic R&D and a lot of engineering needed. R&D and prototype cost would be less than ITER, the International Tokamak Experimental Reactor (fusion). Lots of messy politics because of concern about nuclear weapons proliferation, however. And NIMBY. No chance of an uncontrolled reaction, since turning off the proton beam stops the reaction in under a microsecond (speed of light from source to target).
http://scholar.google.com/scholar?hl=en&q=rubbia+accelerator+transmutation+nuclear+waste&btnG=Search/
Carlo Rubbia proposed this around 1990, six years after his Nobel prize. http://en.wikipedia.org/wiki/Carlo_Rubbia/
https://accelconf.web.cern.ch/accelconf/e94/PDF/EPAC1994_0270.PDF/
A High Intensity Accelerator for driving the energy applifier for nuclear energy production. C. Rubbia et al.
Another citation: http://arjournals.annualreviews.org/doi/abs/10.1146%2Fannurev.nucl.48.1.505/
ACCELERATOR-DRIVEN SYSTEMS FOR NUCLEAR WASTE TRANSMUTATION (1998 review)
Charles D. Bowman
The ADNA Corporation, Accelerator-Driven Neutron Applications, Los Alamos, New Mexico 87544; e-mail: cbowman@roadrunner.com
Abstract The renewed interest since 1990 in accelerator-driven subcritical systems for transmutation of commercial nuclear waste has evolved to focus on the issue of whether fast- or thermal-spectrum systems offer greater promise. This review addresses the issue by comparing the performance of the more completely developed thermal- and fast-spectrum designs. Substantial design information is included to allow an assessment of the viability of the systems compared. The performance criteria considered most important are (a) the rapidity of reduction of the current inventory of plutonium and minor actinide from commercial spent fuel, (b) the cost, and (c) the complexity. The liquid-fueled thermal spectrum appears to offer major advantages over the solid-fueled fast-spectrum system, making waste reduction possible with about half the capital requirement on a substantially shorter time scale and with smaller separations requirements.
There are ~14000 employees at LANL. I'd guess 20,000 laptop and desktop machines. 0.1% loss per year isn't bad. There's nothing in the article to say when the other 67 might have fallen off the radar.
In deep water submersibles the occupied portion is a sphere to best resist pressure. The rest of the craft is filled with water at ambient pressure. The drawing in the article shows this one to follow that pattern. Your first comment is refuted.
The Trieste was a tethered bathyscape. It went down on a cable and back up again. No ability to survey an area. I'd like to survey deep trenches as possible nuclear waste sites. Put the stuff in wedge shapped containers and drop it into deep muck at the bottom of such trenches. If it's 20m down in muck under 7-11 km of water it's going to be easier to produce new nuclear material than to retrieve
An untethered deep submersible with ability to survey an area could find many useful things on the sea floor. Like how to harvest methane:
http://www.independent.co.uk/news/science/exclusive-the-methane-time-bomb-938932.html
The land area of the Earth has been the subject of intense exploration for millenia yet we're still learning about it. Satellites, a 50 year old vehicle for exploration, have helped immensely. Why do you think a new undersea vehicle will not have a similar effect on ocean exploration?
I ran a magnetic finite element job using a commercial code on Windows XP (company required for this code) which used 15.5 GB of RAM (16 available) and 11 GB of swap. It took five days to run and I couldn't do anything else with the PC, but that's OK - I have an RHEL 5 box next to it.
We had a 20 year old, 5MW transformer go a month ago. Internal bolted connections had loosened in the years since we had last drained the oil to inspect them. There was internal arcing which damaged the connections so badly they had to be replaced. The transformer was drained of oil and shipped off for repair. It was re-installed this week.
We have a vendor sample the oil annually to check for compounds formed during arcing. The oil check picked up the nascent problem about five months ago. We didn't repair it then because the accelerator was operating. When the accelerator was shut down for the summer (electricity price hike) the oil was drained and the problem found to require offsite repair.
We don't have the money to stock spare transformers. CERN seems to. Or at least they have the cash to buy a spare fast and repair the broken one at leisure.
If Fermilab had handled the public relations better before the SSC site decision, the locals might not have opposed it, sending it to Texas. Had the Tevatron been used as the injector for the SSC, as the CERN complex does for the LHC, the cost would have been much less. The SSC might have been running for a decade in this scenario.
Fermilab set up a local committee to discuss the possible siting of the International Linear Collider, a proposed follow-on to LHC which will cost about the same. The lab learned from the SSC mistake. The ILC would be 30-50 miles long but the most complicated stuff, including the detectors, would fit on the Fermilab site of ~6400 acres. The rest goes in a couple of long, deep tunnels.
The magnets use NbTi (niobium titanium) alloy superconductor which has a critical temperature of ~9K. Current capability of a superconductor is a function of the local magnetic field and the temperature. The greater the ratio of critical temperature (9K) to operating temperature, the greater the current that can be carried. 9/4.5=2 while 9/2 =4.5. It's not linear, but one can get to higher fields at the lower temperature, and therefore greater beam energies in the same tunnel. The Tevatron operates at 4.5K, BTW.
I would add the two plasma physics books in print by Lyman Spitzer. There's a reason they named an observatory after him.
I concur with the recommendations of Feynmann and Landau & Lifshitz.
It's been some 37 years since I made the switch from math to plasma physics, then applied superconductivity and now accelerator physics.
The DOE Office of Science has multiples sub-offices, including Fusion, Basic Energy Sciences, High Energy Physics and Nuclear Physics. Fusion: The 2008 Omnibus spending bill cut all US funding for ITER, the International Tokamak Experimental Reactor. Basic Energy Sciences: mostly funds small university groups and the accelerator "light sources" and particle sources those groups use. It didn't suffer too badly. Most of SLAC's funding now comes from BES. There are still some groups at SLAC working on high energy physics in connection with Fermilab and CERN (LHC). High Energy Physics - Fermilab is the only high energy physics lab left in the US. As was mentioned above, the last high energy experiment at SLAC was shut down prematurely as a result of the 2008 budget. The Tevatron at Fermilab will be shut down at the end of either FY09 or FY10, depending on budgets and the progress of LHC. Nuclear Physics - Funds the CEBAF accelerator at Jefferson Lab, the RHIC accelerator at Brookhaven, and the university groups which do research at either. These people look at nuclei - how they hang together, how the particles within each proton or neutron behave in a nucleus rather than when they're all "alone" as in a high energy experiment, etc.
I run large electromagnetic finite element problems on a machine with 16GB of DDR2 with two Xeon Dual Cores at 2.66 GHz on XP64. One job takes about four days. I can run two in parallel before memory gives out. If my firm had $20K available I'd get a machine with 64GB of DDR3 at "1600 MHz" and dual quad-core at 3.2GHz. I could run larger jobs or more in parallel and they might take only three days - two iterations per week.
The first day will likely be spent in paperwork and safety briefings. One of the key things you should be told is "bio-safety level". Depending on location and age (over 18 or not) you may be restricted as to the level of organisms you can deal with. ----- Most important trait: Ask questions. Ask dumb questions. Ask questions even if you feel embarrassed not knowing the answer. You don't want to hurt yourself or a colleague by guessing. Nor does your employer want you to screw up an experiment by guessing, but that's secondary to safety.
Getting a first draft, however bad, out for review is critical. There are few people comfortable writing first drafts of procedures. Everyone literate is willing to comment and suggest improvements. I like http://www.atlassian.com/software/jira/ as a vehicle for organizing input, if you have the money. twiki.org is also used here.
pulse length is ~10 fs or 3 microns at the speed of light. Since most of the stuff one looks at is at thermal velocities, this is certainly a macroscopic freeze frame. To look at steps of chemical reactions, sub-femtosecond pulses are desirable. Google "energy recovery linac" (ERL) for information on a mechanism for getting such short pulses. UK was hoping to build an ERL-based light source at Daresbury but the budget news out today http://physicsworld.com/cws/article/news/32163 suggests this won't go ahead for a while.
There are about 700 million air trips per year. I estimate that the unnecessarily increased screening is 1 hour each versus pre-9/11. 8760 hours/year, so 79,909 years. At 80 years/life, about 1000 lives. If you assume the average passenger has lived half his/her life, 2000 lives per year.
Why "unnecessarily increased"? Increased screening for weapons is not needed due to strengthened crew doors. Shoe removal for everyone is not justified by one idiot who couldn't get the fuse to light - the ban on matches and cigarette lighters suffices. Ditto ban on liquids due to the incident in Britain in which their authorities later admitted the stuff couldn't have been mixed into an explosive in the air.
Explosives in checked and carry-on luggage like Lockerbie, a real concern, still aren't covered by sniffers at many airports.
What wouldn't be theatre? Carry-on and checked luggage through x-ray and explosives sniffer. Person through metal detector and explosives sniffer. No random checks. No shoe removal.
If the US lost four or fewer planes a year to in-sky explosions without significant ground damage the rest of us would come out ahead.
It seems strange that they didn't aim for the retro-reflector placed by one of the Apollo missions which has been used for 30+ years for laser ranging experiments. It's location is well known. That would give them a real 800,000 km beam path, roughly half of what they claimed.