Download DetectorActivities

“Detector activities” after the
IB upgrade
Michele Punturo
What we must do
• 0 priority:
– commissioning
• 1 priority:
– Items to be implemented
•
•
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Acoustic shielding in the laser lab
Improvement of the cleanliness procedure in the towers
New coil drivers
… (MC LC windows?) …
– Items to be investigated:
• MC end mirror
– Better substrate
– Heavier payload
• BS mirror
– Larger mirror
» Reduce scattered light
•
•
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Eddy current dissipation
New electronics
Thermal compensation & Phase camera
New quadrant centering devices (galvanometers)
…
Virgo+ Activities
• New high power laser
– N. Mann
• FS monolithic suspension activities
– M.Punturo
Acoustic Shielding in the LL
• Reduce the cross talk between the acoustic channel and
the dark fringe
• All the racks with fans displaced during the shutdown
• A coverage of the laser table and of the external injection
bench is under design
– Two offers received:
• 30 k€
• 16 k€
– A third company contacted
• Offer in few days
– Implementation:
• End of winter, beginning of spring
• As soon as an executive design will be available it will be shown in
a detector meeting
Cleanliness improvement in the tower
• Wednesday, past week:
• When the NI problem occurred I prepared (16/04/2003) this list of rules:
– Keep the mirror clean
– Remove the dust particles through an ionized air jet after the
integration and tuning procedures
– Inject, during the venting only dray air
– Warm up the mirror, to reduce the probability of condensation on it
• Some of them haven’t been respected
– Need to patch the problem now (cleaning intervention)
– Need to solve the problem in the future
• Control of the moisture
• Ionized warm air flux (need of infrastructure upgrade, already indicated in
the urgent purchases in the October 2005 Detector Meeting in Naples)
G.Losurdo
Actuation Noise
New coil drivers
• New coil drivers have been designed by INFN Pisa + EGO
support to solve the actuation noise problem
– Two different sections
• High power section for lock acquisition
• Low noise section for linear regime
– The two sections are driven by two independent DACs
• Full production of new coil drivers
in one year
– Prototypes already installed in
the end towers (EM
contamination)
– Simplified solution in the input
towers (switch+resistor)
– Simplified solution in the BS
tower
Transconductance Amplifier
DAC 1
Coil Driver
Ref. Mass Coil
DAC 2
+
RCo i l
10
RN
O UT
5 00
-
1
L Co i l
3 mH
R2
R
R1
R
2
NEW end MC mirror
• The losses in the MC are 846 ppm (F.Bondu)
instead of 115 ppm
• Defects and contamination in the curved MC mirror
• This mirror must be replaced
Small or large MC mirror?
• Two new small substrates have been sent to GS
Lumonics (Raffaele, could you confirm?)
• The possibility to use a large substrate must be
investigated
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–
–
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Better control of the payload
“almost” standard geometry
Herasil substrate available
Movement mechanics complicated
Optics + Mechanics studies must be started now
New BS?
• Stray light is evident in the BS
WA
IB
NI
wedge
• With the higher injected power the problem should be enhanced
– Larger BS needed
• New substrate (wedge) to be realized
Eddy current FUTURE problem
• Virgo design
• Current design
– M=0.017 A m2
– Stainless Steel RM
– M=0.05 A m2
– Aluminum RM
• sRM=1.4×106W-1m-1
• sRM=3.2×107W-1m-1
– Qeddy=1.8×108
– Qeddy=9.4×105
h (f)
[1 /s q rt(H z )]
Experimental test: (VIR-NOT-PER-1390-27 (1996),
VIR-NOT-PER-1390-80 (1997), Rev.Sci.Instr. 69,
1 0
2777 (1998))
-1 8
1 0
-1 9
1 0
-2 0
1 0
-2 1
1 0
-2 2
1 0
-2 3
(a
(b
(c
(d
1
1 0
)
)
)
)
N
C
N
M
o m in a l V ir g o
u rre n t m a g n e ts M = 0 .0 5 , A l R M
o m in a l m a g n e ts M = 0 .0 1 7 , A l R M
a g n e ts M = 0 .0 0 5 , A l R M
1 0 0
F re q u e n c y [H z ]
1 0 0 0
coil
magnet
post
mirror
Aluminum RM
steel support
Macor support
Magnetic Field Now
With Iron Hat
Test in Clean Room
Bmeas
Model
Model (top larger)
1.0
B/B 0
0.8
0.6
0.4
0.2
0
1
2
layers of 0.6mm
3
Conclusions
• In parallel to the commissioning activities
many “detector activities” are foreseen
(and many more are needed)
• Man power is an issue:
– Many persons are involved in both
commissioning and “detector”