Detector activities after the IB upgrade

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Detector activities after the IB upgrade

• Michele Punturo

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What we must do

• 0 priority
• commissioning
• 1 priority
• Items to be implemented
• 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
• Eddy current dissipation
• New electronics
• Thermal compensation Phase camera
• New quadrant centering devices (galvanometers)

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Virgo Activities

• New high power laser
• N. Mann
• FS monolithic suspension activities
• M.Punturo

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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

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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 havent 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)

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Actuation Noise
G.Losurdo
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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
  (switchresistor)
• Simplified solution in the BS tower

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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

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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
• Better control of the payload
• almost standard geometry
• Herasil substrate available
• Movement mechanics complicated
• Optics Mechanics studies must be started now

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New BS?

• Stray light is evident in the BS

• With the higher injected power the problem should
  be enhanced
• Larger BS needed
• New substrate (wedge) to be realized

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Eddy current FUTURE problem

• Virgo design
• M0.017 A m2
• Stainless Steel RM
• sRM1.4106W-1m-1
• Qeddy1.8108

• Current design
• M0.05 A m2
• Aluminum RM
• sRM3.2107W-1m-1
• Qeddy9.4105

Experimental test (VIR-NOT-PER-1390-27 (1996),
VIR-NOT-PER-1390-80 (1997), Rev.Sci.Instr. 69,
2777 (1998))
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Magnetic Field Now
steel support
Aluminum RM
Macor support
coil
magnet
post
mirror
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With Iron Hat
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Test in Clean Room
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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