Salvatore Buontempo INFN Napoli on behalf of the FOS4CMS Group CERN Ginevra (Svizzera) CNR Napoli Uni Sannio Benevento Uni Federico II Napoli ATOMKI Debrecen (Ungheria) NIKIET Mosca (Russia) OptoSmart Napoli Napoli, 17 Settembre 2012
Fiber Optic Sensor Community (academic and industrial partners) FOS4CMS Group CMS Collaboration @ CERN FOS4HEP Project 2
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 3
TEMPERATURE CHANGE B 2 n eff Thermal expansion for Termo-optic effect for n eff Where: n eff is the effective refractive index of the fiber, Λ is the grating pitch and λ B is the reflected Bragg wavelength. STRESS Elasto-optic effect for Direct Strain for n eff 4
STRAIN AND TEMPERATURE Sensitivity : FBG Spectral Response (Temperature) FBG SPECTRAL RESPONSE: Temperature Shift Temperature Sensitivity 10pm/ K @ λ B =1550nm T 5
STRAIN AND TEMPERATURE Sensitivity: FBG Spectral Response (Axial Strain) FBG SPECTRAL RESPONSE: Axial Strain Shift Strain Sensitivity 1pm/με @ λ B =1550nm ε 6
The Compact Muon Solenoid (CMS) experiment in CERN P5 site (Cessy - France) 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 Napoli, 17 Settembre 2012 SIF XCVIII Congresso Nazionale 8
Second interrogator for additional 16ch being installed in these days CMS today can read up to 2000 FBGs! 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 Detector Cavern (UXC) 100 m underground 120 m fiber lenght distance Service Cavern (USC) 70 m underground 9
Temperature sensors on the Silicon Tracker Bulkheads 10
Positive side: Goal: check the T distribution on bulkhead and along the cable tray Compare T distribution before (FOS) and after (electronic sensors) bulkhead Napoli, 17 Settembre 2012 SIF XCVIII Congresso Nazionale 11
Negative side: 20 sensors installed in July 2009. Installation time: 4 hours Additional cables: 1 fiber split in two to reach positive and negative bulkheads Napoli, 17 Settembre 2012 SIF XCVIII Congresso Nazionale 12
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 13
14
Temperature sensors in the UXC cavern 15
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 Napoli, 17 Settembre 2012 FOS operation in CMS 16
16.4 16.6 16.4 16.9 16.8 17.1 17.5 All values in C 18.6 17
18
Top of shaft feels the summer Shaft Far Side on Balcony HF+ YB Gap+3 YB0 YB Gap-3 HF- Near Side on Balcony -END X0 +END 19
zoom zoom Shaft Shalf open S7 S6 S5 S4 S3 S8 zoom Happens at the same time (every day a bit later than before): Direct sunlight effect on top shaft sensor S7! S2 S1 20
Temperature sensors on Cathod Strip Chamber (ME+4/1) 21
Goal: measure T on electronic frame (not cooled and cooled areas) vs the beam collision rate Very fast Installation : 1h to install a Y splitter one of existing fiber and put 2 new T sensors on the new fiber 22
Result : No T effect on CSC electronics induced by beam on/off nor by beam interaction rate 23
PLT (Pixel Luminosity Telescope) Temperature measurements 24
~ 10 cm LHC pipe Goal: Monitor T on PLT electronic card vs beam collision intensity in an independent mode. FBG installation VERY close to LHC beam pipe, in a very forward region (very high radiation dose mostly due to non ionising particles) 25
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) 26
Near Side (Array1) Array could be installed without any problem. Spectrum is as clear as it was read out close by interrogator PLT monitor in CMS control room 27
28
~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 29
Strain measurements on Forward Hadronic Calorimeter 30
Castor detector dismounted in Dec 2011 Monitor the mechanical effect 31
IP side (positive) Not IP side (negative) 32
Last ramp down in 2011 First ramp up in March Last ramp down in 2011 First ramp up in March Napoli, 17 Settembre 2012 SIF XCVIII Congresso Nazionale 33
Last ramp down in 2011 First ramp up in March Lower and upper sensors behave different with (2011) and without (2012) Castor Detector Napoli, 17 Settembre 2012 SIF XCVIII Congresso Nazionale 34
Very visible effect of CASTOR removal B field result: simmetric Extension effect on both sides Napoli, 17 Settembre 2012 Near side SIF XCVIII Congresso Nazionale Far side (grey lines: last two rampups in 2011)
Very visible effect of CASTOR removal B field result: simmetric Compression effect on both sides (grey lines: last two rampups in 2011) Near side Far side Napoli, 17 Settembre 2012 SIF XCVIII Congresso Nazionale (grey lines: last two rampups in 2011) 36
Very visible effect of CASTOR removal on UP sensors Near side Far side Napoli, 17 Settembre 2012 SIF XCVIII Congresso Nazionale (grey lines: last two rampups in 2011) 37
Visible effect of CASTOR removal Near side Far side Napoli, 17 Settembre 2012 SIF XCVIII Congresso Nazionale (grey lines: last three rampdowns in 2011) 38
Visible effect of CASTOR removal Fast dump (green line) did not diverge from the slow dump behavior Near side Far side Napoli, 17 Settembre 2012 SIF XCVIII Congresso Nazionale (grey lines: last three rampdowns in 2011) 39
Very visible effect of CASTOR removal on UP sensors Near side Far side Napoli, 17 Settembre 2012 SIF XCVIII Congresso Nazionale (grey lines: last three rampdowns in 2011) 40
@ 3.8T displacement 13 (10) mm 5mm (4.5mm) Rear of CASTOR 0.5 1.5mm 13mm 1.5mm BP Support 13,36m extension Strain ε~80 µm/m Strain ε~ -50 µm/m compression Napoli, 17 Settembre 2012 0mm 0mm
Napoli, 17 Settembre 2012 S
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. Napoli, 17 Settembre 2012
Fibers on the Collar Platform and on the Table S4 S3 S2 S1 S1;S2;S3;S4 T1;T2 Strain ε~50 µm/m Conclusion: the Collar Platform and the Table are strong enough; all displacement of Forward Zone depends on raiser tower deformation only. Napoli, 17 Settembre 2012 S5;S6;S7;S8 T3
CMS survey report confirmed the displacements 4.4mm 1.9mm 1.3mm -1.4mm @ 3.8T Napoli, 17 Settembre 2012 Data by Joao Antunes
Additional CMS T and strain FOS installations planned in 2013 LS1 46
Temperature sensors on RE4 47
2.0m 1.4m 1.0m Goal: monitor T on RPC strips for each of 72 detector chambers in a disk endcap Napoli, 17 Settembre 2012 SIF XCVIII Congresso Nazionale 48
2 independent arrays: Array R2: 36 FOS 1.4m distant each, tails 8m each with connectors on both ends 2.0m Array R2 1.4m 1.0m 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) Array R3 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 Napoli, 17 Settembre 2012 No magnetic element in FOS packaging and splicing. SIF XCVIII Congresso Nazionale 49
RE4 RE3 RE2 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. Disk 1 CMS FOS Rack In total: additional 72x6= 432 T sensors to be installed and read out Napoli, 17 Settembre 2012 SIF XCVIII Congresso Nazionale 50
Strain on YE4 disk 51
YE4 shielding disk Strain sensors on the YE4 disk (2x18 sensors) to monitor deformations induced by B field 52
Strain and T on new CMS central beam pipe 53
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 54
Development of New Sensors for HEP based on FBG technique (FOS4HEP) 55
FBG sensor Buffer Cladding Core Bragg Grating Napoli, 17 Settembre 2012
Napoli, 17 Settembre 2012 Coating Material
By using a functionalized coating material, i.e. mechanically sensible to the variations of the parameter to monitor Napoli, 17 Settembre 2012
Relative Humidity sensors for CMS Tracker 59
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 Miniaturized humidity sensors used at CERN HIH 4000 series by Honeywell 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 Precon HS2000 Capacitive Small Size Easy in use Direct reading of Dew Point NOT radiation hard Sensitive to B fields Hygrometrix HMX 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) Napoli, 17 Settembre 2012 Radiation hardness capability SIF XCVIII Congresso Nazionale 60
..Use of FBG as RH sensor is not new in literature.. Bare FBG is insensitive to humidity. Use of sensitive material as coating of the FBG to induce a mechanical effect Sensing principle Realization of humidity sensor by coating the gratings with a polyimide film Absorbtion of moisture by the polymeric coating Expansion of the coating ( swelling ) Strain induced on the FBG Bragg wavelength shift _ measured f ( T, RH %) B S T T S RH RH Temperature compensation is needed RH SENSOR COUPLED TO T SENSOR B _ RH Napoli, 17 Settembre 2012 B_ measured B_ T POLYIMIDE COATING FBG1 uncoated T- SENSOR FBG2 coated RH SENSOR Lambda variation only due to RH variations 61
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!! 70 65 60 55 F6_RH_1 cal based on SHT15 F6_RH_2 cal based on SHT15 F6_RH_3 cal based on SHT15 F6_RH_4 cal based on SHT15 SHT15 E.g. Calibration of Array F6-RH-1_4 in BOX A 50 45 40 35 30 25 20 15 0 500000 1000000 1500000 2000000 2500000 3000000 3500000 4000000 Napoli, 17 Settembre 2012 t(sec) SIF XCVIII Congresso Nazionale Calibration based on the data provided by the analogic reference sensors (SHT15_RH) RH-FOS s readings very compatible to SHT15_RH!! 62
Additional CERN FOS projects triggered by FOS4CMS group (for more detail see also Prof. L. Rossi talk tomorrow) 63
Wavelength shift [nm] 0 FBG sensitivity 8-12 pm/k @ room T < 0.1 pm/k below 40 K a base material with a large thermal expansion coefficient at cryogenic temperature needs to be selected Potential use of FOS for temperature monitoring in very extreme value ranges (max. 700 C and min 1.9 K) -5-10 -15-20 Polymers are the best candidates warm up Teflon warm up PMMA2 warm up PMMA1-25 0 50 100 150 200 250 300 Temperature [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) Napoli, 17 Settembre 2012 Reduction of instrumentation and improvement of workplace safety in the upgraded tunnel 64
Temperature and stress profile from winding to operation for new generation SC magnets: challenge for Nb3Sn materials that is STRAIN SENSITIVE Potential use of FOS for strain 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 FBG sensors and strain gauges glued on the Aluminum shell of the magnet Low heat in-leak into the bath and less wires needed in comparison with the standard strain gauges Napoli, 17 Settembre 2012 Quench monitoring 65
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 66
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 67
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 68