Minutes: SBS Meeting March 6, 2013 
Attendees: Bogdan Wojtsekhowski, John LeRose, Sergey Abrahamyan, Charles Perdrisat, Evaristo 
Cisbani, Carlos Ayerbe Gayoso, Doug Higinbotham, Seamus Riordan, Vahe Mamyan, Kondo Gnanvo, 
Alexandre Camsonne, Nilanga Liyanage, Mitra Hashemi Shabestari, Brian Quinn
A somewhat unusual meeting, a snowstorm in Charlottesville with a consequent power failure limits 
UVa people. 
1)	Nilanga Liyanage gives status report on GEM developments at UVa
a)	All needed parts arrived early last week. Now have all components needed to construct two 
GEM chambers.
b)	Started construction a few days ago
i)	Gives details of activities
(1)	Checking various components
(2)	Bogdan is worried about leakage current on frames
(3)	Bogdan is also worried about the maximum current from the power supply during ramp 
up. Do you trust the power supply to stop at a few micro-Amps? Recommends testing 
the power supply before risking a GEM. All agree.
(4)	Clean room protocols discussed. In particular vacuuming was discussed. Recommended 
that one vent the vacuum outside the clean room. (Put the vacuum machine outside 
and run an extension hose into the clean room would work too.)
ii)	Stretcher is ready
iii)	Expect to finish the 1st chamber in the next couple of weeks and have both chambers by 
sometime in April.
c)	Showed two plots (linkx linky)
i)	Used two small chambers sandwiching a large chamber.
ii)	Plots show residuals between the small chambers and the large chamber
iii)	Just proof that the system works. Will work to improve and study systematics.
d)	Electronics:
i)	Put in an order for INFN designed electronics for testing
ii)	Also plan to expand SRS (from CERN) electronics setup
iii)	Electronics costs are low compared to expectations.
2)	Bogdan proposes a collaboration meeting in the May timeframe. Will work on finding an optimum 
time. 

-JJL