1. Napoli, 17 Settembre 2012 Salvatore Buontempo INFN Napoli on behalf of the FOS4CMS Group CNR Napoli Uni Sannio Benevento Uni Federico II Napoli ATOMKI Debrecen (Ungheria) NIKIET Mosca (Russia) OptoSmart Napoli CERN Ginevra (Svizzera)

2. Napoli, 17 Settembre 2012 2 Fiber Optic Sensor Community (academic and industrial partners) SIF XCVIII Congresso Nazionale CMS Collaboration @ CERN FOS4CMS Group FOS4HEP Project

3. Napoli, 17 Settembre 2012 3 FBG concept Overview of FOS sensors in CMS FOS Infrastructure in CMS Temperature measurements in CMS with FOS  Silicon Tracker Bulkheads  CMS Underground cavern (UXCsite)  Cathod Strip Chamber (CSC-ME4/1)  Pixel Luminosity Telescope (PLT) Strain measurements in CMS with FOS Hadron Forward Calorimeter support Additional CMS T and strain FOS installations planned in 2013 LS1 T on RPC Forward Strain on YE4 disk T and Strain on new central Beam Pipe Development of new sensors for HEP based on FBG technique(FOS4HEP) Relative Humidity T and Strain Measurement in Cryogenic environment SIF XCVIII Congresso Nazionale

4. Napoli, 17 Settembre 2012 4 Where: n eff is the effective refractive index of the fiber, Λ is the grating pitch and λ B is the reflected Bragg wavelength. TEMPERATURE CHANGE Thermal expansion for Termo-optic effect for STRESS Elasto-optic effect for Direct Strain for SIF XCVIII Congresso Nazionale

5. Napoli, 17 Settembre 2012 5 Temperature Sensitivity ≈10pm/°K @ λ B =1550nm T STRAIN AND TEMPERATURE Sensitivity : FBG Spectral Response (Temperature) FBG SPECTRAL RESPONSE: Temperature Shift SIF XCVIII Congresso Nazionale

6. Napoli, 17 Settembre 2012 6 STRAIN AND TEMPERATURE Sensitivity: FBG Spectral Response (Axial Strain) FBG SPECTRAL RESPONSE: Axial Strain Shift Strain Sensitivity ≈1pm/με @ λ B =1550nm ε SIF XCVIII Congresso Nazionale

7. Napoli, 17 Settembre 2012 The Compact Muon Solenoid (CMS) experiment in CERN P5 site (Cessy - France)

8. Napoli, 17 Settembre 2012 Sensors placed to the following areas in CMS (133 sensors): –HF region negative side (Raiser and Castor table 10 + 6 sensors) –Tracker bulkhead on both side (10 +10 sensor) –Experimental Cavern (60 sensors) in January 2011 –PLT T-sensors (13 sensors) 2012 –T/RH tests in the cavern/cooling plants, (12+12 sensors) 2012 in 2009 Aim: demonstrate feasibility in very hostile environment monitor mechanical deformations induced by field (HF-) monitor T in detector and in the environment 8 SIF XCVIII Congresso Nazionale

9. Napoli, 17 Settembre 2012 9 A backbone of 72 fibers was installed between X1 near and S2C18 New patchpanel is added to S2C18 New 1U 16 channel interrogator in the system SIF XCVIII Congresso Nazionale Service Cavern (USC) 70 m underground Detector Cavern (UXC) 100 m underground 120 m fiber lenght distance Second interrogator for additional 16ch being installed in these days CMS today can read up to 2000 FBGs !

10. Napoli, 17 Settembre 2012 10 Temperature sensors on the Silicon Tracker Bulkheads SIF XCVIII Congresso Nazionale

11. Napoli, 17 Settembre 2012 Positive side: 11 SIF XCVIII Congresso Nazionale Goal: check the T distribution on bulkhead and along the cable tray Compare T distribution before (FOS) and after (electronic sensors) bulkhead

12. Napoli, 17 Settembre 2012 Negative side: 12 SIF XCVIII Congresso Nazionale 20 sensors installed in July 2009. Installation time: 4 hours Additional cables: 1 fiber split in two to reach positive and negative bulkheads

13. Napoli, 17 Settembre 2012 13 SIF XCVIII Congresso Nazionale 20 sensors running without any problem since July 2009 24h, 7/7. Only pause is due to Maintenance Winter shutdown (25 days in January). High radiation dose: no effect of LHC ON/OFF, no aging detected so far High Magnetic Field (3.8T): no effect of B field ON/OFF No interference with other subdetectors and electronics close by

14. Napoli, 17 Settembre 2012 14 SIF XCVIII Congresso Nazionale Trk 512 – pBH 8 Trk 548 – pBH 8 Trk 556 – pBH 5 Trk 556 – pBH 10 Trk 518– pBH 9 Trk 572 – pBH 9 Trk 564 – pBH 8 Right, near Left, far Trk 564 – pBH 7 Tracker temperature data are measured by the Tracker Team (Andromachi Tsirou et al.) Overshooting and ‘not perfect’ correlation between the two datasets are due to the relatively large deadbands defined for the Tracker temperature data. Trk 512 – pBH 8 Trk 548 – pBH 8 Trk 556 – pBH 5 Trk 556 – pBH 10 Trk 518– pBH 9 Trk 572 – pBH 9 Trk 564 – pBH 8 Right, near Left, far Trk 564 – pBH 7 Tracker temperature data are measured by the Tracker Team (Andromachi Tsirou et al.) Overshooting and ‘not perfect’ correlation between the two datasets are due to the relatively large deadbands defined for the Tracker temperature data.

15. Napoli, 17 Settembre 2012 15 Temperature sensors in the UXC cavern SIF XCVIII Congresso Nazionale

16. Napoli, 17 Settembre 2012 16 Additional 60 FBG T sensors were installed in 2011 in UXC, positioning a single fiber (2km long ) in 3 days: - 23 sensors on wall near side - 3 sensors on wall +Z side - 23 sensors on wall far side - 8 sensors on shaft far side - 3 sensors on wall -Z side FOS operation in CMS

17. Napoli, 17 Settembre 2012 17 16.4 16.6 16.9 16.8 17.1 17.5 18.6 All values in °C SIF XCVIII Congresso Nazionale

18. Napoli, 17 Settembre 2012 18 SIF XCVIII Congresso Nazionale

19. Napoli, 17 Settembre 2012 19 YB0YB Gap-3 YB Gap+3 Shaft X0 Far Side on Balcony  Near Side on Balcony  HF+HF- Top of shaft feels the summer… -END +END SIF XCVIII Congresso Nazionale

20. Napoli, 17 Settembre 2012 20 Shaft SIF XCVIII Congresso Nazionale Shalf open zoom Happens at the same time (every day a bit later than before): Direct sunlight effect on top shaft sensor S7 ! S7 S8 S6 S5 S4 S3 S2 S1

21. Napoli, 17 Settembre 2012 21 Temperature sensors on Cathod Strip Chamber (ME+4/1) SIF XCVIII Congresso Nazionale

22. Napoli, 17 Settembre 2012 22 Goal: measure T on electronic frame (not cooled and cooled areas) vs the beam collision rate SIF XCVIII Congresso Nazionale Very fast Installation : 1h to install a Y splitter one of existing fiber and put 2 new T sensors on the new fiber

23. Napoli, 17 Settembre 2012 23 Result : No T effect on CSC electronics induced by beam on/off nor by beam interaction rate SIF XCVIII Congresso Nazionale

24. Napoli, 17 Settembre 2012 24 PLT (Pixel Luminosity Telescope) Temperature measurements SIF XCVIII Congresso Nazionale

25. Napoli, 17 Settembre 2012 25 ~ 10 cm SIF XCVIII Congresso Nazionale Goal: Monitor T on PLT electronic card vs beam collision intensity in an independent mode. LHC pipe FBG installation VERY close to LHC beam pipe, in a very forward region (very high radiation dose mostly due to non ionising particles)

26. Napoli, 17 Settembre 2012 26 No additional FOS clear fibers were installed in the PLT Zone Instead of installing a new monomode clear fiber dedicated for FOS, we tried to use a spare PLT DAQ existing optical link PLT link goes directly to USC, therefore only a short patch cable had to be installed in USC between the PLT and FOS racks In addition FC/APC connectors had to be changed to MU (only MPO-MU fanouts are accessible) SIF XCVIII Congresso Nazionale

27. Napoli, 17 Settembre 2012 27 Near Side (Array1) Array could be installed without any problem. SIF XCVIII Congresso Nazionale Spectrum is as clear as it was read out close by interrogator PLT monitor in CMS control room

28. Napoli, 17 Settembre 2012 28 SIF XCVIII Congresso Nazionale

29. Napoli, 17 Settembre 2012 29 ~2 degC T drift since march (beam ON) On/off status has no effect on T drift Cavern T looks quite stable PLT warms up? Any other effect?... Still under evaluation SIF XCVIII Congresso Nazionale

30. Napoli, 17 Settembre 2012 30 Strain measurements on Forward Hadronic Calorimeter SIF XCVIII Congresso Nazionale

31. Napoli, 17 Settembre 2012 31 SIF XCVIII Congresso Nazionale Castor detector dismounted in Dec 2011 Monitor the mechanical effect

32. Napoli, 17 Settembre 2012 32 SIF XCVIII Congresso Nazionale IP side (positive) Not IP side (negative)

33. Napoli, 17 Settembre 2012 Last ramp down in 2011 First ramp up in March 33 SIF XCVIII Congresso Nazionale

34. Napoli, 17 Settembre 2012 Last ramp down in 2011First ramp up in March Lower and upper sensors behave different with (2011) and without (2012) Castor Detector 34 SIF XCVIII Congresso Nazionale

35. Napoli, 17 Settembre 2012 Near sideFar side (grey lines: last two rampups in 2011) SIF XCVIII Congresso Nazionale B field result: simmetric Extension effect on both sides Very visible effect of CASTOR removal

36. Napoli, 17 Settembre 2012 Near side Far side Very visible effect of CASTOR removal (grey lines: last two rampups in 2011) 36 SIF XCVIII Congresso Nazionale B field result: simmetric Compression effect on both sides

37. Napoli, 17 Settembre 2012 Near sideFar side (grey lines: last two rampups in 2011) 37 SIF XCVIII Congresso Nazionale Very visible effect of CASTOR removal on UP sensors

38. Napoli, 17 Settembre 2012 Near sideFar side (grey lines: last three rampdowns in 2011) 38 SIF XCVIII Congresso Nazionale Visible effect of CASTOR removal

39. Napoli, 17 Settembre 2012 Near side Far side Visible effect of CASTOR removal (grey lines: last three rampdowns in 2011) Fast dump (green line) did not diverge from the slow dump behavior 39 SIF XCVIII Congresso Nazionale

40. Napoli, 17 Settembre 2012 Near sideFar side (grey lines: last three rampdowns in 2011) 40 SIF XCVIII Congresso Nazionale Very visible effect of CASTOR removal on UP sensors

41. Napoli, 17 Settembre 2012 0mm compression extension displacement Strain ε~80 µm/m Strain ε~ -50 µm/m 0mm 13 (10) mm Rear of CASTOR BP Support 13,36m 0.5÷1.5mm 5mm (4.5mm) 13mm @ 3.8T 1.5mm

42. Napoli, 17 Settembre 2012 S

43. In the conditions without B field the calculations done using FOS data correspond to those done with Previous ANSYS analysis. In B field conditions FOS data are the only source of info about real force induced by B field. B field simulations are available but it is very difficult to include all the effects of present metallic structure.

44. Napoli, 17 Settembre 2012 Conclusion: the Collar Platform and the Table are strong enough; all displacement of Forward Zone depends on raiser tower deformation only. Fibers on the Collar Platform and on the Table S5;S6;S7;S8 T3 S2 S1;S2;S3;S4 T1;T2 S1 S3 S4 Strain ε~50 µm/m

45. Napoli, 17 Settembre 2012 CMS survey report confirmed the displacements @ 3.8T 1.9mm 1.3mm -1.4mm 4.4mm Data by Joao Antunes

46. Napoli, 17 Settembre 2012 46 Additional CMS T and strain FOS installations planned in 2013 LS1 SIF XCVIII Congresso Nazionale

47. Napoli, 17 Settembre 2012 47 Temperature sensors on RE4 SIF XCVIII Congresso Nazionale

48. Napoli, 17 Settembre 2012 1.4m 1.0m 2.0m 48 SIF XCVIII Congresso Nazionale Goal: monitor T on RPC strips for each of 72 detector chambers in a disk endcap

49. Napoli, 17 Settembre 2012 2 independent arrays: Array R2: 36 FOS 1.4m distant each, tails 8m each with connectors on both ends Array R3: 36 FOS 1.8m distance each, tails 6m each with connectors on both ends Lambda distribution in each array should allow to have 72 picks (36 R2 + 36 R3) uniformly distributed in 80 nm bandwidth (to be checked) On each array : Max attenuation on sensor n.36 (last) is 10 dB On arrayR2+array R3 in serial mode: Max attenuation on sensor n.72 (last) is 20 dB No magnetic element in FOS packaging and splicing. 49 SIF XCVIII Congresso Nazionale

50. Napoli, 17 Settembre 2012 Two arrays installed on each disk with both connectors on the near side rack panel (4 connectors on each disk) 4 clear fibers + 2 spare to be positioned from each disk up to disk 1 rack panel = 18 fibers for each endcap (all in near side passing in mini cable chain) 18 + 18 = 36 clear fibers to be positioned from disk 1 up to CMS FOS patch panel in X1. Path being discussed with Integration Office. CMS FOS Rack Disk 1 RE2 RE3 RE4 50 SIF XCVIII Congresso Nazionale In total: additional 72x6= 432 T sensors to be installed and read out

51. Napoli, 17 Settembre 2012 51 Strain on YE4 disk SIF XCVIII Congresso Nazionale

52. Napoli, 17 Settembre 2012 52 YE4 shielding disk Strain sensors on the YE4 disk (2x18 sensors) to monitor deformations induced by B field SIF XCVIII Congresso Nazionale

53. Napoli, 17 Settembre 2012 53 Strain and T on new CMS central beam pipe SIF XCVIII Congresso Nazionale

54. Napoli, 17 Settembre 2012 54 Strain and Temperature sensors along the new beampipe (4x10 sensors) We intend to monitor the sag with strain sensors on top and bottom of pipe We will monitor the T distribution along the beam pipe Very high radiation dose SIF XCVIII Congresso Nazionale

55. Napoli, 17 Settembre 2012 55 Development of New Sensors for HEP based on FBG technique (FOS4HEP) SIF XCVIII Congresso Nazionale

56. Napoli, 17 Settembre 2012 CladdingCore Bragg Grating Buffer FBG sensor

57. Napoli, 17 Settembre 2012 Coating Material

58. Napoli, 17 Settembre 2012 By using a functionalized coating material, i.e. mechanically sensible to the variations of the parameter to monitor

59. Napoli, 17 Settembre 2012 59 Relative Humidity sensors for CMS Tracker SIF XCVIII Congresso Nazionale

60. Napoli, 17 Settembre 2012 NEEDS AND REQUIREMENTS FROM CERN FOR RELATIVE HUMIDITY SENSORS Low mass Small dimensions Insensitivity to magnetic field Operation at temperature down to -40˚C Response to the full range [0, 100]% RH Reduced number of wires needed Reliable reading across long distances High long term stability and/or possibility of an easy remote recalibration Radiation resistance to dose up to 1 Mgy Capacitive Small Size Inexpensive 3 wires for each RH measuring point Accuracy of 3,5%RH Response time 15s Minimum operation temperature -40°C NOT Radiation hard HIH 4000 series by Honeywell Miniaturized humidity sensors used at CERN Precon HS2000Hygrometrix HMX Capacitive Small Size Easy in use Direct reading of Dew Point NOT radiation hard Sensitive to B fields Resistive Small size Tolerant to radiations Extremely low response Complex chain of read-out over long distances Highly not linear signal NOT AVAILABLE on the market any more OUR SOLUTION: Fiber Optic Sensors based on FBG technology Multiplexing capability (Reduction of cabling complexity) Radiation hardness capability 60 SIF XCVIII Congresso Nazionale

61. Napoli, 17 Settembre 2012..Use of FBG as RH sensor is not new in literature.. Absorbtion of moisture by the polymeric coating Expansion of the coating (“swelling”) Strain induced on the FBG Bragg wavelength shift Realization of humidity sensor by coating the gratings with a polyimide film Bare FBG is insensitive to humidity. Use of sensitive material as coating of the FBG to induce a mechanical effect Sensing principle POLYIMIDE COATING FBG2 coated RH SENSOR FBG1 uncoated T- SENSOR Temperature compensation is needed RH SENSOR COUPLED TO T SENSOR Lambda variation only due to RH variations 61

62. Napoli, 17 Settembre 2012 RH-FOS’s readings very compatible to SHT15_RH!! Calibration based on the data provided by the analogic reference sensors (SHT15_RH) 1)RH tests in climatic chambers (controlled in temperature) 2)Installation of 3 boxes with RH FOS in CMS site (cooling plant) We are presently working on the calibrations of 80 RH FOS sensors RH FOS are providing VERY good results in first real environment application in CMS UXC site If correctly calibrated they are reproducing quite well data from reference sensors, but they are radiation hard !! E.g. Calibration of Array F6-RH-1_4 in BOX A 62 SIF XCVIII Congresso Nazionale

63. Napoli, 17 Settembre 2012 63 Additional CERN FOS projects triggered by FOS4CMS group (for more detail see also Prof. L. Rossi talk tomorrow) SIF XCVIII Congresso Nazionale

64. Napoli, 17 Settembre 2012 a base material with a large thermal expansion coefficient at cryogenic temperature needs to be selected FBG sensitivity 8 - 12 pm/K @ room T < 0.1 pm/K below 40 K Potential use of FOS for temperature monitoring in very extreme value ranges (max. 700 °C and min 1.9 K) with high precision and fast response (aim to locate rapidly possible hot spot) over long distances: Superconducting links (power transmission cables to be cooled with Helium gas up to 20 K between the LHC tunnel and the surface) Reduction of instrumentation and improvement of workplace safety in the upgraded tunnel Polymers are the best candidates 64

65. Napoli, 17 Settembre 2012 To monitor the strain and the strain distribution of the coils and of the magnet structure during assembly, cool down, powering and warm up To monitor the strain variation during assembly, cool down powering and warm up To detect quenches Low heat in-leak into the bath and less wires needed in comparison with the standard strain gauges Temperature and stress profile from winding to operation for new generation SC magnets: challenge for Nb3Sn materials that is STRAIN SENSITIVE FBG sensors and strain gauges glued on the Aluminum shell of the magnet Quench monitoring Potential use of FOS for strain 65

66. Napoli, 17 Settembre 2012 66 We have a clear expression of interest from CMS Collaboration for additional application of fiber sensors for: Magnetic field measurement Gas detection Vibration monitoring Radiation monitoring / Dosimetry SIF XCVIII Congresso Nazionale

67. Napoli, 17 Settembre 2012 67 FOS4CMS project started in 2009 and is rapidly expanding year by year At present we have about 150 sensor running without ANY problem since 3 years 24h, 7/7, T and strain monitoring in hostile environment without any problem We have installed a facility ready to handle 32 fibers (about 2000 sensors) fully compatible with CERN software standard We have already received requests for additional 700 sensors to be installed in next year of maintenance/upgrade (RPC, YE4, new beam pipe, tracker) R&D on new fields of application of FBG technique with custom coating are giving very positive and interesting results Relative Humidity sensors for low range and high precision have been produced in mass scale (100 pieces). Reliability is impressive. Calibration on goin. Intallation in March 2013 in CMS Tracker. First prototypes for Cryo T and Cryo Strain are both giving very positive results (see Prof. L. Rossi talk tomorrow onLHC upgrade) Additional requests from CMS and HEP for new fields of application of FOS technique SIF XCVIII Congresso Nazionale

68. Napoli, 17 Settembre 2012 68 Optical Fiber Sensor Technology is becoming a new reference standard in CMS and in HEP Great example of interdisciplinary collaboration between academic and industrial partners FOS validation and impressive stable/reliable results in very hostile environment (high radiation and high electromagnetic field) will open more field of application for technology transfer SIF XCVIII Congresso Nazionale