Navigation Links
Spallation Neutron Source sees first target replacement
Date:7/27/2009

OAK RIDGE, July 27, 2009 -- Having outlasted all expectations of its service life, the original mercury target of the Spallation Neutron Source (SNS), the Department of Energy (DOE) Office of Science's record-setting neutron science facility at Oak Ridge National Laboratory, is being replaced for the first time.

SNS operators are taking advantage of a planned maintenance outage to replace the old target, which has been in service since the SNS's startup on April 28, 2006.

"We were anticipating this operation as far back as the summer of 2008, and the fact is that the target received nearly twice the cumulative beam as its projected lifetime limit. In the meantime, neutron scientists have been reveling in the beam intensities the SNS is already providing," said ORNL Director Thom Mason, who directed the SNS before becoming laboratory director.

The mercury target is the first of its kind. A proton beam generated by the SNS's linear accelerator strikes the target 60 times per second with a force comparable to bursts from a large-caliber machine gun, "spalling" neutrons from the circulating mercury inside.

Eventually, the wear and tear of those forces were expected over time to damage the stainless steel of the target and render it unusable. The target is modular: It can be changed out whenever necessary. Some researchers estimated the first change would become necessary a year ago.

One reason for the target's longer than expected life could be the decision to run the SNS at lower power--and step up the SNS's power more slowly--to give experiments that are already being conducted more stable beam time. Replacing the target during the maintenance outage avoids interruptions of experiments.

With a maximum design beam power of 1.4 megawatts, the SNS has been routinely operating at just under 500 kilowatts. Already the world's most powerful neutron source, every time power is stepped up, a new record is established.

"Even at these power levels, our scientific users have been ecstatic with the results they are getting from their experiments," said SNS Director Ian Anderson.

The SNS team has already operated the facility at close to megawatt levels. Recent tests verified that the linear accelerator and accumulator ring--two vital components that supply the proton beam pulses--are meeting and exceeding the 1.4 megawatt design criteria.

The replacement operation entails decoupling the target module and retracting it from the beam line area after draining the mercury--approximately 20 tons of it--from the vessel. Then the new module is put into place, returned to the target station and then refilled with the mercury. The entire process is performed with remote manipulators by operators working in a control room adjoining the target bay--a procedure that will be repeated each time the target is changed, which ultimately at full power could occur several times a year.

The old target will be studied to gauge how three years of proton bombardment have affected its materials.


'/>"/>

Contact: Bill Cabage
cabagewh@ornl.gov
865-574-4399
DOE/Oak Ridge National Laboratory
Source:Eurekalert

Related biology news :

1. Interacting protein theory awaits test from new neutron analysis tools
2. Pittsburgh scientists identify human source of stem cells with potential to repair muscle
3. UNH becomes first university in nation to use landfill gas as primary energy source
4. New partnership offers outsourced R&D in membrane biology
5. HortTalks, a valuable scientific resource
6. Reversing cognitive deficits: Injectable antibody may attack source of problem
7. The race for biofuels driving alternative sources of biomass
8. Space technology put into service for global water resources observations
9. Local sources major cause of US near-ground aerosol pollution
10. The power of multiples: Connecting wind farms can make a more reliable - and cheaper - power source
11. GBIF making the search for biodiversity research resources easier
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:4/17/2017)... , April 17, 2017 NXT-ID, Inc. (NASDAQ: ... announces the filing of its 2016 Annual Report on Form 10-K ... Commission. ... 10-K is available in the Investor Relations section of the Company,s ... the SEC,s website at http://www.sec.gov . 2016 Year ...
(Date:4/13/2017)... India , April 13, 2017 According to ... Proofing, Identity Authentication, Identity Analytics, Identity Administration, and Authorization), Service, Authentication Type, ... MarketsandMarkets™, the IAM Market is expected to grow from USD 14.30 Billion ... Growth Rate (CAGR) of 17.3%. ... MarketsandMarkets ...
(Date:4/11/2017)... Research and Markets has announced the addition of the "Global ... ... at a CAGR of 30.37% during the period 2017-2021. ... based on an in-depth market analysis with inputs from industry experts. ... the coming years. The report also includes a discussion of the ...
Breaking Biology News(10 mins):
(Date:4/20/2017)... , April 20, 2017 Dutch philosopher Koert van Mensvoort ... Nature, at the University of Technology in Eindhoven - has written a ... letter, he calls on humanity to avoid becoming a slave and victim to ... ... Dutch philosopher Koert van Mensvoort – founder of the Next ...
(Date:4/19/2017)... (PRWEB) , ... April 18, 2017 , ... Alisa Wright, ... Distinguished Alumni Awards from the Purdue College of Pharmacy in Lafayette, Indiana. , ... Pharmacy Program for achievements in their careers and other scientific endeavors. , Wright ...
(Date:4/19/2017)... Yorba Linda, Ca (PRWEB) , ... April 19, ... ... Virtual University Virtual Event, which makes educational webinars accessible to novices as ... and impact of preanalytical variables of commonly performed coagulation screening tests. , ...
(Date:4/19/2017)... Mass. , April 19, 2017   ... results from the multi-center Procalcitonin MOnitoring SEpsis (MOSES) ... print issue of Critical Care Medicine . ... Mortality in Severe Sepsis Patients: Results From the ... use of the B·R·A·H·M·S PCT (procalcitonin) assay to ...
Breaking Biology Technology: