Update on LHC Inner Triplets

To strengthen the support structure of the magnets in the "inner triplet," cartridges will be attached to one of the ends of the Q1 magnet and to one of the ends of the Q3 magnet.

A team of experts from CERN, from CEA-Saclay (a French national laboratory), and from Brookhaven National Laboratory met at CERN on April 24 and 25 to review proposed solutions to the problems that caused the failure of a Fermilab-built "inner triplet" of superconducting magnets during a routine pressure test on March 27. Physicists and engineers from Fermilab and Lawrence Berkeley National Laboratory participated in the review.

Each triplet contains three superconducting magnet assemblies, a cryogenic and power distribution box for the magnets, and associated structures. The triplets will focus particle beams prior to particle collisions in the Large Hadron Collider, now under construction at CERN. The pressure test took place in the accelerator tunnel.

The CERN review team examined the mechanical design of the inner triplet to make sure that there are no further hidden defects and conducted a review of the proposed in-situ repairs.

The reviewers examined the proposed repair method to hold the magnet's cold mass in place inside its cryostat, or outer metal jacket, to keep the magnet from moving when it experiences an asymmetric longitudinal force. During the pressure test, the existing magnet support structure broke in response to such a force.

The solution presented to the review panel will use four long metal cartridges installed parallel to the magnets long axis. The cartridges will be welded to the magnet's cold mass and to a bracket attached to the cryostat. The review panel made detailed recommendations for verifying the cartridges' ability to hold the magnet in place under a wide variety of possible conditions during accelerator operations.

Pine Street entrance closing extended:
Use Wilson Street entrance
Due to repaving operations, both the inbound and outbound lanes of Fermilab's Pine Street entrance will continue to be closed through Tuesday, May 1. Each day the Pine Street entrance will be closed at 6 a.m. and will reopen by 6 p.m. The Wilson Street entrance will be open between 6 a.m. and 6 p.m. Motorists on outbound Pine street should be cautious of rough uneven surfaces, bumps, water on road and the lack of pavement markings. The schedule is dependent on the weather. Fermilab Today will provide updates.

Lira Ensemble: A Musical Celebration of Poland
The Lira Singers and Dancers will present "A Polish Musical Celebration" at the Fermilab Arts Series, featuring the music and dance of Poland on Saturday, May 5th at 8:00 p.m. Additional information is available here.

Village pool passes on sale May 1
Season pool passes go on sale in the recreation office beginning May 1. The village pool opens May 26 over Memorial Day weekend. A family pass (2-4 members) is $95.00 and $9.00 for each additional family member. A single pass is $55.00. Season passes are available to Fermilab employees, visitors, on-site contractors, their immediate families and retirees. More information and registration forms can be found in the recreation office or on the recreation office website.

Village water system flushing
Flushing of the Village domestic water system is scheduled for Saturday, April 28, between 6:30 a.m. and 4:00 p.m. There may be some discoloration of tap water and possibly brief loss of water pressure during the flushing procedure. Residents are encouraged to avoid using washing machines to prevent laundry discoloration from rust.

Coed softball league: Call for teams and players
The Coed softball league is looking for players and teams. Softball season starts May 9. Games are held on Wednesday evenings at 5:15 and 6:30 p.m. at the Fermilab softball field. Interested persons should email Dave Hockin.

Upcoming Activities