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In this issue:
New AT&T Cell Tower Online
Have CMS and ATLAS Reached the Top?
Trusty Old Fire Alarms Give Way to New Technology

SLAC Today

Monday - July 26, 2010

New AT&T Cell Tower Online

(Photo - new AT&T cell tower)
 (Photo by Yee-Ting Li.)

AT&T customers should have noticed an improvement in their cell phone signal at SLAC beginning late last week. A temporary cell tower, which went up behind Building 50 late last month, now provides service to the SLAC campus and immediate surrounding areas. A permanent tower will be installed on the roof of Building 50 after a seismic retrofit of the building is completed, within the next year.

The permanent tower will improve coverage even more; the temporary tower will not have the full coverage on the north side of the SLAC campus that is expected from the permanent one, which will have a better vantage point from its planned location on the roof of Building 50.

Earlier in July, the California Highway Patrol submitted their approval of the tower after "E911" emergency services locator testing and surveys of the coverage were completed. After minor delays in connecting the base station at SLAC and the Mobile Telephone Switching Office for the area, the tower went live Thursday.


Have CMS and ATLAS Reached the Top?

The top at ATLAS? (Image: ATLAS.)

It might be a long way to the top, but experiments at the the Large Hadron Collider are already half-way there. Friday at the International Conference on High Energy Physics in Paris, the CMS and ATLAS experiments presented their first top quark candidates. These candidates are collisions that have all the hallmarks of having produced top quarks, but the experiments don't yet have enough data to be 100 percent sure that the events created top quarks that decayed into other particles, rather than another type of event.

"The signal is starting to rise from the background," noted Tim Christiansen from CMS.

Read more in Symmetry Breaking.

Trusty Old Fire Alarms Give Way to New Technology

These old telegraphic fire alarm boxes have become collector's items. (Photo by Ralph Kerwin.)

The iconic red fire alarm boxes that have adorned SLAC since its opening day will soon disappear, victims of technological obsolescence. These Gamewell master boxes are part of a telegraphic fire alarm system that has been reporting SLAC fire alarms to emergency responders since 1968.

The technology is old but reliable. When the alarm box is triggered, a spring-loaded, toothed wheel spins and taps out the coded, four-digit box number. The first such system was installed in Boston in 1845. SLAC's version of the technology—known as a McCulloh loop—works so well that the underlying arrangement has remained largely unchanged since it was patented in 1882. It was the predominant institutional fire alarm reporting technology nation-wide well into the 1970s. Due to their ruggedness and reliability, Gamewell systems remain in use in several major U.S. cities, including San Francisco, as the ultimate post-disaster municipal alarm system.



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