Despite its size, ATLAS is not a completely stationary detector. It has a stationary infrastructure but it does have some parts that can move around, allowing for access to the internal elements of the detector. (By contrast CMS is very mobile–it is like a gigantic Yule log where each section can be separated from each other.) On each side of ATLAS, there are three big moveable parts as seen in this picture. The muon wheels shown by the turquoise arrow can be moved back. This allows for the end-cap magnets indicated by the red arrow to be pulled out. Once the end-cap is moved, we can gain access to the extended barrel calorimeters (such as TileCal). The extended barrels shown by the blue arrow can also move forward, allowing for access to the calorimeter barrel as well as the inner detector. But space is limited so it is not possible to access all places at once. And so in typical ATLAS fashion, there are committees in place to organize who gets access when.
But the end of April is ‘the closing’. Or perhaps I should say THE CLOSING. Or maybe even, THE CLOSING.
Where all the moveable parts are put into their final location. And the installation of the beam pipe and the beam pipe shielding begins.
The bad news is that we will lose access to the detector. The good news is that it means the beam is coming.
The closing is one of those things that can simultaneously fill you with ecstatic excitement and absolute panic. And it really is a simultaneous feeling. On one hand it is like sitting in a Ferrari waiting for the keys. Feeling the pressure of the seat against your back, the feel of the wheel under your hands, anticipating the roar of the engine when you hit the gas and thinking, ‘Alright. Show me what 0 to 60 really means.’ And yet at absolutely the same moment, it is like the night before your last final exam. Staring intently at a pile of books, willing the information to leap out of the pages and into your brain, lamenting, ‘why didn’t I get to this sooner’, but knowing that it was impossible in any case because you had other exams which took precedent.
But heedless of anyone’s feelings on the subject, the closing approaches. And I will bet that as it continues to approach the two most common phrases in the halls will be either ‘We are closing soon, the beam will be here!’ or ‘We are closing soon, and it is the end of January already. How did it get to be the end of January already?!’.
The end of April, it is so far and yet so close.
Tags: ATLAS
Monica,
At last a term I am used to! You might be interested to learn that “the closing” is well-known to corporate accountants and also creates a significant amount of anxiety. Every one, bar the lunatics and masochists, hates closing. Closing of the accounts is generally performed every month, although “harder” closings are being effected quarterly, culminating into the year-end (full financial year) closing. In a nutshell, it consists of stopping the count of the various on-going company transactions and to correct the picture with “accruals” (in order to reflect any timing difference between – to simplify- revenue and the underlying costs) as well as with “provisions” (accounting for any identifiable risk) with the aim of presenting the “truest” and “fairest” view about the company’s profitability and net wealth. You do not wish to have to explain why the comfortable profits you had measured for ,say the January to May period suddenly transmuted into a loss at the end of June. You, physicists, may be delighted to evidence a missing mass following an event and to speculate as to what the balance is made up of, but shareholders generally have a more limited sense of humour, as is being illustrated by the plumetting of the Société Générale share price following their recent announcement of an unexpected $7billion loss.
Fortunately I stopped playing this dangerous game several years ago. Wishing you the best for your own closing!
Monica,
Best wishes for complete success in ‘the closing’ of ATLAS! I would hope that this remarkable milestone might also provide an opportunity for all to make observations and offer suggestions in support of future endeavors of this type in our field.
And to that end, I must confess that I cannot help but notice that such closings and inevitable reopenings would probably be improved with the Radial Wedge Flange Clamp. This is a compact, remotely accessible, quick-connect and disconnect device that can be aplied to virtually any type of metal to metal flange and sealant.
This problem solver was developed and proven at the Thomas Jefferson National Accelerator Facility. U.S. Patent 6,499,774 B1 was granted for the invention on 31 DEC 02, and some progress has been made toward commercialization.
Aside from ease of installation and efficient use of increasingly costly space (that gets tighter with every upgrade), this innovation can also significantly reduce the dose of residual radiation received by workers when installing and removing accelerator vacuum components.
Perhaps others will find this new technology helpful, and regardless of whether or not you and your colleagues are among them, best wishes again for THE CLOSING! And stay safe!!
Karl