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In this issue:
Winter Break Phone Shutdown: Does Your ALD Know Where You'll Be?
ATLAS' Countdown to Collisions

SLAC Today

Tuesday - December 8, 2009

Winter Break Phone Shutdown:
Does Your ALD Know Where You'll Be?

Calling all SLACers: Access to the SLAC site will be limited during the winter shutdown, December 19 through January 3, due to scheduled maintenance projects including needed upgrades to the lab's central phone system on December 26 and 27. If you plan to do any work on-site during the break, please double-check that your manager (and through him or her, your associate laboratory director or other division head) knows about it, today.

Over the break, work classified as "red" or "yellow" in SLAC's Work Planning and Control system will be allowed only for pre-approved projects. Staff who must do "green" work, such as office work, will be allowed on site and in their offices without preapproval—with two exceptions. First, several buildings will have major utility interruptions (e.g., no power) during parts of the shutdown, and access to those buildings will be limited. (Details to come later this week.) Second, on Saturday and Sunday, December 26 and 27, the phone system will be offline. On those days, only personnel on pre-approved list will be allowed to enter SLAC, regardless of whether the planned work is "red," "yellow" or "green." Staff coming on site will be required to follow a pre-approved emergency communication protocol, provided by SLAC's emergency management team, as SLAC phones (650-926-xxxx) will be down and unable to make 911 calls.

SLAC operations, computing and safety staff have gathered a list of projects scheduled for winter break, through weekly "Plan of the Week" meetings, where representatives of each directorate present upcoming work plans. Today is the deadline for any final additions, changes or designations of "red" or "yellow" work. The submitted projects will be reviewed this week, and a list of approved work will be returned to each ALD on Monday, December 14.

Please help by making sure your management knows all work planned for the break, so that your ALD can communicate any updates to your Plan of the Week representative today. Please contact Janice Dabney with any questions.

Watch SLAC Today for additional information about the winter shutdown, including which buildings will be affected by utility shutdowns and the telephone system project, in the coming days.

ATLAS' Countdown to Collisions

(Image - ATLAS detector diagram and candidate collision event)
First 900 GeV candidate collision events in the ATLAS detector, November 23, 2009.

ATLAS, at 148 feet long, 82 feet high and 82 feet wide, has the largest volume of any particle detector ever built and is designed to study the products of high-energy proton-proton collisions. Over the past year, ATLAS has been upgrading, repairing, and preparing for Large Hadron Collider collisions, which began on Monday, November 23. In the four months preceding the first collisions, the ATLAS collaboration's focus shifted from repair and installation to getting all pieces of the complex ATLAS detector operating as one. Here's a look at how ATLAS prepared for collisions.

First, a checkup—4 months until collisions
When the ATLAS detector is closed up and ready for beam, the innermost portions are inaccessible. Therefore, much attention is paid to infrastructure maintenance when the commissioning process begins. ATLAS' Luca Fiorini explained, "The detector is built like a Russian doll. There are things that we cannot repair once the cavern is closed and the magnets are on, though there are still outer levels that we can work on."

Several weeks over the summer were devoted to maintenance work on ATLAS’ 12 sub-detector units and their internal components. Infrastructure maintenance occurred on all three levels of ATLAS: the inner detector, calorimeters, and muon chambers, to be sure that no wires were crossed and all detector channels were calibrated to work together.

Read more in Symmetry Breaking...


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