Keeping up with the neutron crowd
Control room at the Spallation Neutron Source.
In today's column, I mentioned that a delegation from Sweden was at ORNL last week to learn a bit more about SNS and its impacts, etc. Well, a delegation from Denmark apparently was in before them, for much the same. The Scandinavian folks are teaming in hopes of acquiring a European version of the SNS known as ESS (European Spallation Source).
Earlier this week, I talked on the phone with Ian Anderson, ORNL's neutron sciences chief, to try to catch up on a few things, including the European activity and the latest with SNS. The other competitors for the ESS, by the way, are Spain and Hungary.
Anderson said the goings-on in Europe won't negatively affect the Oak Ridge science center. It seems there's plenty of demand for neutrons to do experiments.
One of the critical issues for any of these neutron sources is what's to be used as the target, and it a decision that faced Anderson directly when he joined the Spallation Neutron Souce team back in March 2002. As most folks know -- at least those who care -- the SNS folks decided on a liquid metal target (mercury), which has certain advantages and disadvantages.
What I didn't realize until I was talking with Anderson is that the Oak Ridge-based SNS is considering a different target for its second Target Building, which is in an early stage of development known as 'mission need' or Critical Decision-0.
Although the baseline calls for Target 2 to have a mercury target, the SNS folks and various review teams are evaluating the possibility of a rotating solid target of tungsten, Anderson said. The rotating part would keep the beam from battering the solid target in the same place all the time, which can creates all sorts of negative issues.
Anderson said would positive about a solid target is that it would avoid the cavitation issue associated with the liquid mercury target. As the mercury is hit many times a second by a high-powered proton beam, it creates bubbles that collapse and release energy against the walls of the target container.
Anyway, nothing is settled at this point on Target 2, but it's all real interesting.
The second Target Building at SNS has not been funded, of course, and that won't be the easiest thing in the world. According to Anderson, it could cost in the range of $700 million to $900 million with funding charted for 2012 and beyond. If that sounds a bit much, remember that the investment could potentially double the number of instruments available to researchers and, well, pretty much double the amount of science produced there.
The second Target at SNS apparently would create what's called a long-pulse station as opposed to the short-burst variety currently doing the deal at Oak Ridge. Anderson said a slower, longer pulse at lower frequency is highly favorable for certain types of experiments, and I guess I'll take his word for that.
More on this later.
Frank Munger will be covering the Dept. of Energy's Oak Ridge facilities and other things nuclear. The blog will include random thoughts and opinions, behind-the-scenes tidbits, and expanded coverage and analysis of Oak Ridge news. 