Matthew Moulson (Frascati) for the LAV Working Group NA62 Photon-Veto Working Group Meeting CERN, 17 July 2012 LAV construction & installation status

LAV construction status – M. Moulson (Frascati) – Photon Veto WG – CERN – 17 July 2012 A11 construction status 2 Completed and tested 6/7 Rotation and vacuum testing week of 9/7 Full survey with laser tracker 17/7 and 18/7 Shipment scheduled for 24/7 (delivery 25/7) Leak test: < 2×10 −9 mbar∙ℓ/s

LAV construction status – M. Moulson (Frascati) – Photon Veto WG – CERN – 17 July 2012 A11 transport plans 3 Shipment with Fasoli scheduled for 24/07 – Delivery to CERN 25/07 A8 transport 10 May Shipping container modified Outer diameter ~ 3 m Container width ~ 3.5 m Width > 3 m = Wide Load Need police escort! Mount Blanc Tunnel shut down both directions (Approval requested)

LAV construction status – M. Moulson (Frascati) – Photon Veto WG – CERN – 17 July 2012 Status of A9, A10 vessels 4 Start-up meeting INFN-Fantini on 9 May at Fantini (Anagni) Can stainless steel with μ/μ 0 = 1.01 be obtained? Generally suppliers will make no guarantees about μ/μ 0 Fantini-INFN tour of proposed suppliers of stainless steel to take measurements of 304L plate stock (plus comparisons 304LN, 316L, etc.) INFN will investigate if criterion for μ/μ 0 can be relaxed Measurement of μ/μ 0 for existing stainless steel segments of blue tube Average μ/μ 0 for 304L plate stock (before working): – 1.020

LAV construction status – M. Moulson (Frascati) – Photon Veto WG – CERN – 17 July 2012 Measurements of μ/μ 0 for existing tubes 5

LAV construction status – M. Moulson (Frascati) – Photon Veto WG – CERN – 17 July 2012 Conclusions: μ/μ 0 for existing tubes 6 Typical μ/μ 0 measurements for tube inside magnet gap (#25) Flanges1,05-1,10 Tube wall1,01-1,04 Supports 1,04-1,10 Welds 1,60-1,90* *Also verified that there are no peaks of μ/μ 0 on flanges that could suggest the presence of welds Typical μ/μ 0 measurements for adjacent tubes (#24, #27) Flanges1,05-1,10 Tube wall1,01-1,30* *These tubes are made from individual plates welded together. The value of μ/μ 0 varies significantly from plate to plate.

LAV construction status – M. Moulson (Frascati) – Photon Veto WG – CERN – 17 July 2012 Status of A9, A10 vessels 7 Plate steel for A9 cylinder: Ordered from Outokumpu (CR) 2 plates, 9 m long, 40 mm thick, 304LN (stabilized in nitrogen) Characteristically low permeability Usually very expensive (€17/kg ~ 4× cost of 304L), but highly discounted Flanges: Ordered from a foundry near Varese Forged 304L, to be solubilized after forging to obtain low μ/μ 0 Production will be monitored 200-mm nozzles: Cut from whole steel on cannon mill, can be solubilized if needed All material should be delivered by end of Sep 2012 A9 vessel delivery: late Jan/early Feb 2013 A10 vessel delivery: late Jun 2013