Status in SR8

1. Status in SR8 Martyn Davenport 22.05.06 PATRAS Collaboration meeting

2. Status in SR8 • SR8 last 2 months • End of shutdown • Start of data-taking (details Jaime) • Comments on data-taking • Shutdown for PATRAS • Comments on CAST PC network • LHC 8 cryogenic tests (quenches) soon • Validity of CAST data ? (Zaragoza) • TAO • Coherence • Windows • Roadmap for 3He system • Updated roadmap • 3He cold windows • Schedule • MM line installation • 3He system • 50mbar end 2007? • Timetable for request for extension • Conclusions PATRAS Collaboration meeting

3. Mini-grid points magnet moving as in sun tracking SR8 last 2 months • End of shutdown • Change magnet movement drive cables • TPC much less noise • MM more noise ??? (need experts to debug) • Bake-out RT vacuum line MFB-MRB • Reduce long-term outgassing of H2O onto windows • Cool-down magnet • OK, no leaks found on cryostat/new VT3 • Sun filming • Julia to report • Check of mis-alignment V1 V2 vacuum lines (inside MFB) with vacuum in cryostat • OK • Mini-GRID • OK (I believe) very similar to previous ones • However - should we realign the magnet ? • GRID & sun tracking do not agree (Julia?). • Hence do we understand measurements well enough to move ? • We need a meeting of experts to decide (video +Juan?) • TAO tests by Nuno with new cold bore pressure probe • Power up magnet • 1 training quench 1 arc min radius PATRAS Collaboration meeting

4. SR8 last 2 months • Startup eventful • MM test of MM line elements compatibility with CCD-Telescope • Problems – modifications needed • Problems with MM V4/V3  V5 • CCD turbo, late service Eco-dry primary • Unstable vacuum in CCD (H2 bubbles rising from newly-maintained eco-dry) • Bojon solved in 1 hr in between other jobs – brilliant. No replacement yet. • Start of data-taking (details Jaime) • MM Misalignment (see next slide) • TPC source calibrator arm • Quench on last shift – CERN-wide power cuts. • New mechanical support technician – Yves (paid by CAST CERN ‘in kind contribution’) • Comments on data-taking (see Jaime’s report) • Jaime doing a great job as run coordinator (+ TPC expert+ default shifter) • Number people at CERN inadequate since restart • Heavy load on personnel at CERN ( MM not fully covered, …….) • Several breakdowns – difficult decisions change or not pressure • Strategic spares essential, systems already running for 3 years. • Already broken ad hoc rules concerning changing gas pressure • Feedback from detectors MM & CCD (computer Munich) sometimes slow PATRAS Collaboration meeting

5. Micromegas alignment after intervention Was 5 mm Need response from MM in next days – another adjustment of alignment ? Was -11 mm When CCD telescope + MM line which beam line to align ? PATRAS Collaboration meeting

6. SR8 last 2 months • Start of data-taking (details Jaime) • MM Misalignment (see next slide) • TPC source calibrator arm • Quench on last shift – CERN-wide power cuts. • New mechanical support technician – Yves (paid by CAST CERN ‘in kind contribution’) • Comments on data-taking (see Jaime’s report) • Jaime doing a great job as run coordinator (+ TPC expert+ default shifter) • Number people at CERN inadequate since restart • Heavy load on personnel at CERN ( MM not fully covered, …….) • Several breakdowns – difficult decisions change or not pressure • Strategic spares essential, systems already running for 3 years. • Already broken ad hoc rules concerning changing gas pressure • Existing = (sunrise) >90% telescope (sunset) >50% • Feedback from detectors MM & CCD (computer Munich) sometimes slow PATRAS Collaboration meeting

7. SR8 last 2 months • Shutdown for PATRAS • Agreed at Zaragoza • Trying to exploit time • Laura – maintenance of failing compressor + cryogenic quench recovery procedure • Nuno – tests with / without window heaters • Must fix schedule today and send to Tapio instructions (see next slide) • Program for Nuno • MM realignment ? • Some outstanding jobs • Install Drytel # 2 on MRB (see slide) • Leak test (Bojon) • Test functionality of interlocks • Complete installation horizontal and vertical magnet position reference systems • CAST PC network • Discussions with CERN network experts • Must either follow CERN standards or go alone and take consequences • No CAST expert available to make decision and take responsibility • Main problem is Juan’s PC. Taking steps to clone it with new equipment for eventual replacement PATRAS Collaboration meeting

8. PATRAS Collaboration meeting

9. Nuno -Should we do V=+/- 8 for completeness ? Ioannis – should we realign the MM? PATRAS Collaboration meeting

10. SR8 last 2 months • Some outstanding jobs • Install Drytel # 2 on MRB (see slide) • Leak test (Bojon) • Test functionality of interlocks • Complete installation horizontal and vertical magnet position reference systems • CAST PC network • MD doesn’t understand enough to make decision • Discussions with CERN network experts (+ Thomas & Silvia & Markus) • Must either follow CERN standards or go alone and take consequences • No CAST expert available to make decision and take responsibility • Main problem is Juan’s PC. • Taking steps to clone it with new equipment for eventual replacement • LHC 8 cryogenic tests (quenches) soon – could affect CAST strongly • Requested study into decoupling CAST from LHC 8 (will cost significant money) • No reply from TS-EL group –overloaded by LHC work) • now have to go up TS hierarchy PATRAS Collaboration meeting

11. Validity of CAST data • Zaragoza worries • TAO/Window spots/Coherence • TAO • See Nuno for details • No longer my main worry. • Coherence • CAST in unchartered territory • Cold windows/helium filling cold bore/heaters on cold window flanges • Thermal gradients/density gradients along magnet • Yannis Semertzidis & Markus supervising a simulation • Yannis concludes coherence loss from spatial separation axion/photon not a worry GOOD • End effects due to cold window region being at higher temperature (with/without heaters) • Nuno making good progress modeling • How to distinguish between end effects outside cold bore & magnet –long gradients? • Tests on CAST with laser • When install MM need system ready • Program of measurements/ definition and preparation of hardware • University institutes have specialists to advise? • Ideally Need system similar to time-domain reflectometry in cables PATRAS Collaboration meeting

12. How about spatial coherence? axions  x-rays r n’ x-ray refraction: • The x-rays/axions do not overlap • The x-rays travel longer paths than axions n i The coherence is lost… The important parameter here is pressure uniformity in cross section… PATRAS Collaboration meetingYannis Semertzidis, BNL

13. A numerical example For a 10m long magnet the axion/photon missing each other by 1/2 wavelength when PATRAS Collaboration meetingYannis Semertzidis, BNL

14. Example with 4He gas Generalized for any ma PATRAS Collaboration meetingYannis Semertzidis, BNL

15. Checking the temperature uniformity • Can use a laser light to probe the uniformity, e.g. 5mK temperature gradient in the cross section, along the whole length of the magnet can produce up to 4mmshift on a red laser light…(effect goes as (1/2)2= 20002=4106). PATRAS Collaboration meetingYannis Semertzidis, BNL

16. Validity of CAST data • Windows • Window heaters - history • Spots on windows discovered just before data-taking • No way to monitor with all detectors installed on beam pipes • ‘Wet’ TPC recently – outgassing from plexiglass • H2O, Ar, CH4 • Limit opening times VT1&2 to tracking time • Motivated move to make true differential pumping (order DRYTEL #2) • Window heating should we turn it off? • End effects penetrating into cold bore (Nuno looking into this) • Will get more significant as gas density increases? • Do all tests possible to provide data • Starting this week (heaters on/off + tilting magnet) • Turn off heating  more frozen material accumulating on windows • Estimate ~ 5microns H2O = 15 microns PP window • As gas pressure increases self absorption in gas makes window contamination problem less significant • WHEN TO MAKE DECISION ? Now? 6 mbar (1month)? • Systems to monitor window coatings/transmission • Provision in CF for some developments in this line • In meantime must make protocol for when to bake out the windows • Mr Bojon and Tapio to help in calculation. PATRAS Collaboration meeting

17. Effect of 1 µm ice on window PATRAS Collaboration meeting

18. Roadmap for 3He system • End May • Complete the design report • Submit to CERN cryo-safety committee • Submit to an external referee(s) (MD hasn’t contacted them yet) • Launch any outstanding calls for tender • Conceptual design study of integration of components inside cryostat • First discussion with Central workshop the intervention at end of 2006 • Final cost estimates • June • Complete MOU to allow spending • End June • Technical design review • Green light to start ordering system • Start execution drawings for integration of components inside cryostat • July • Start ordering • November • Must be ready to start intervention work • February 2007 • 3He cold windows must be ready for installation Tapio and Nuno will organize necessary meetings and prepare the technical design report. PATRAS Collaboration meeting

19. 3He cold windows • No work so far done • My priority after CERN-Workpackages & MOU • Provisional plan to start July 2006 (6 months available) • Order more PP15,12,13 • Make 4 good spares for CAST 4He • Make several windows flanges + strongback • CERN + FREIBURG • Make metrology to measure planarity • Glue windows • Progressive pressure tests • Check deformation of strong-back (metrology) • Modify strong-back parameters if necessary • Check deformation of strong-back (metrology) • Cryotests and combined cryo-pressurisation tests • Some modifications to cryolab test system needed • Make and test new windows • Cryolab + Panter PATRAS Collaboration meeting

20. Schedule • When will MM-Line be calibrated and ready for installation? • Can the 3He roadmap be maintained • Should we disrupt data-taking to install MM line before November? • Yes, better to see 1 month data in 2006 • Then know if there are any modifications to do during shutdown • Can synchronizes with changeover to 2-step pressure settings • Will push stoppage for 3He transition later • Will need all time we can to be ready • Make provisional schedule assuming MM-Line ready start September PATRAS Collaboration meeting

21. Provisional CAST Schedule 2006 PATRAS Collaboration meeting

22. Provisional CAST Schedule end 2006-end 2007 PATRAS Collaboration meeting

23. NA48/3 TP; R&D required NA60 LoI for cont. HIE ISOLDE Planned Scientific Programme (MTP June 2005) New tgt; add. beamline Rec. Expts. ILC Expts. PATRAS Collaboration meeting

24. 2 mbar 14 mbar All= TPC and MM & CCD measure all pressure steps Half =TPC measures half steps and CCD/MM the other half All= TPC and MM & CCD measure all pressure steps 1.5 hr per step PATRAS Collaboration meeting

25. Conclusions • See Zaragoza conclusions still relevant (next slide) • Lot of work to be done to be ready for 3He • Significant time recently spent of helping out detector groups • Cannot continue • Nuno (& MD) need to concentrate on 3He preparations not day-day • Need good team in SR8 to cover day-day requirements of data taking • Looking out for potential problems • Need detector representative at CERN • Too minimize intervention times • Ensure good relation with experts in institutes PATRAS Collaboration meeting

26. Comments on data taking in 2006 • Experience of first short data run • Loss of data taking efficiency • Disruption in run planning/pressure changing • Breakdown in hardware • Non- availability of experts • Need essential spares for key equipment • Detector pumps • Beam line vacuum pumps • Computers • Need strategy for computer systems at SR8 • Hardware problems • Some standardisation would be useful (TPC & MM) • Protection against infiltration • Juan PC is a continuing headache as it is cut off from network • Define criterion for acceptable data at a given pressure setting • Existing = (sunrise) >90% telescope (sunset) >50% • Fast feedback from detector fast analysis • Need a team who know the general CAST system (vacuum, He gas) • First line of response if problems • But also to routinely follow tendencies and anticipate problems • A comprehensive shift plan with run coordinators & shifters & general CAST team coverage • Welcome a discussion on these points • A data taking czar appointed to coordinate these issues ? PATRAS Collaboration meeting

27. Conclusions • See Zaragoza conclusions still relevant (next slide) • Lot of work to be done to be ready for 3He • Significant time recently spent of helping out detector groups • Cannot continue • Nuno (& MD) need to concentrate on 3He preparations not day-day • Need good team in SR8 to cover day-day requirements of data taking • Looking out for potential problems • Need experienced person to be data-taking czar • Little decoupled from day-day running • Need detector representative at CERN • Too minimize intervention times • Ensure good relations and contact with experts in institutes PATRAS Collaboration meeting

28. PATRAS Collaboration meeting