S.Burger BE-BI-PM HiRadMat Scientific Board 29th June 2017 HiRadMat New BTV S.Burger BE-BI-PM HiRadMat Scientific Board 29th June 2017 Thanks to the colleagues: M.Bergamaschi (BE-BI), Aymeric Bouvard (EN-EA), E.Bravin (BE-BI), V.Clerc (EN-EA), A.Fabich (EN-EA), A.Goldblatt (BE-BI), A.Guerrerro (BE-BI), JJ.Gras (BE-BI), F.Harden (EN-EA), L.Jensen (BE-BI), K.Kessi (BE-BI), S.Mazzoni (BE-BI), C.Rinaldi (BE-BI), F.Roncarolo (BE-BI), A.Sounas (BE-BI), T.Lefevre (BE-BI), G.Trad (BE-BI), etc... & OP-SPS team !!

Content BTV description New BTV development Specifications Layout Design/Installation Measurements Conclusion

BTV description Insertion device Radiator Lights Camera Holding an in-vacuum radiator Radiator Can be scintillating (Al2O3, ZrO2 etc…) or reflecting material (C, Ti, etc…) depending on the application and type of beam Beam direction Vacuum pipe Lights Mainly used for system calibration and beam steering Glass window Camera Can be standard CCD or special Rad hard (CMOS, CID, Vidicon tube) Optical density filters Can be added in front of the camera to increase the dynamics of the system

New BTV development: Specifications Give beam position and size for all HRM extractions 440 GeV beam 1-288 bunches / 5e9 to 1.7e11p per bunch ( 4.9e13p max) 0.1 < σ < 1.5 mm Max density on screen > 1e15p/mm2 (material choice) Experience gained with: BTV/BPKG instrument Screen test HRM32 experiment in 2016 BTV/BPKG instrument  Robust material for screen  Sigradur G (Glassy Carbon)  In vacuum to avoid parasitic light Energy threshold for Cherenkov emission in air: 37.4GeV  Vacuum < 7.07mbar  Need to cut the forward OTR generated by the vacuum entrance window  give ~30% larger beam size.  Protect camera from backscattering particles  relocate camera in a safe area (optical line) HRM32 experiment

New BTV development: Layout Installation of camera in TT61 to move away from the irradiated zone  Optical line up to TT61, behind shielding Location for camera TT61 TNC New BTV

CATIA 3D drawing of the new BTV for HRM New BTV development: Design/Installation Image from V.Clerc Beam p BEAM Photons Photons Installation of the new BTV HRM from 2017. Located end of experimental table A CATIA 3D drawing of the new BTV for HRM

New BTV development: Design/Installation Photons Camera WATEC 902H3 2 filter wheels for high dynamics (up to OD7) A single lens (Focal length 1m). Magnification of ~0.2 Reference image for calibration Resolution [um/px] Horizontal 72 Vertical 79 Achromatic Lens Focal 1m Diam: 80mm Screen position IN Beam Mirror Diameter 4” Camera lens Focal 75mm + 40mm ring Camera WATEC ULT902H3 ~5m ~0.9m ~0.3m

New BTV development: Design/Installation C foil (fixed) 75um Beam Screens IN New screen setup SiC 0.5mm Ti 0.1mm Chromox 0.5mm Sigradur G Glassy C 0.5mm New screen setup

New BTV development: Measurements Example of beam measurements with the new BTV HRM showing All range of beams can be observed: Up to 48 bunches with scintillation screens Thickness of the screen plays a role on the measurements (as σ ~ thickness) Measurements always larger than OTR Up to 288 bunches with OTR screens (only single bunch (<E11p) with large sigma (>1.5mm) are difficult to observe with OTR) ‘Best results’ obtained so far with SiC screen (matching the theoretical HRM optics) Unfortunately it does not sustain the full beam intensity (breaks the 3rd shots of 288 bunches/σ = 0.3mm)

New BTV development: Measurements Beam: Single bunch ~1e11p FP_0.3mm BTV setup Fixed red filter in front of the camera No OD filter needed for single bunch here SiC (>50 measurements) σH = 0.26mm σV = 0.28mm GlassyC - Sigradur G (>50 measurements) σH = 0.30mm σV = 0.36mm Ti (a few measurments) σH = 0.28mm σV = 0.23mm Measurements very reproductible / systematic OTR measurements difference depending on material (SiC/GlassyC and Ti)  Need some study to better understand (optical aberrations, artefacts, etc ?)

Conclusion Challenging design (small beam + high intensity !) Beam size measurements: we passed from unrealistic results (in air, in radiation area) to realistic ones (in vacuum, camera in a safe location) and we are now close to real ones (with ‘blocking foil’) ! Still some studies to better understand the OTR measurement discrepancy  Need some accesses and beam time ! Thank you !

BACKUP SLIDES

Strips of the BPKG and BTV screen at the back Combined instrumentation: BTV/BPKG: Design BPKG gives a permanent non invasive beam position measurement for each extraction to be correlated with the HiRadMat experiment. Dedicated BTV is used to define BPKG offsets (+ first tests for profile measurement) Position resolution <0.1mm Transvers and Strips of the BPKG and BTV screen at the back Al2O3:CrO2, SiC and Al2O3 (target) screens

BTV/BPKG performance (2) Zoom  Use of scintillating screens: to delay the acquisition on the decay time of the scintillation above a few E12p/mm2  non linearity for low intensity beam above 1E13p/mm2  damage Single bunch (1E11p) Al2O3 screen 12 bunches (1.2E12p) Al2O3 screen T 0.1% Delay 60ms  Use of OTR screens is limited as acquisition must be synchronized with beam (backscattering particles gives high background on camera !) Zoom Can not be used above 12 bunches (not made for anyway) Works fine for BPKG offset setup up 24 bunches (2.4E12p) Al2O3 screen T 100% Delay 280ms 12 bunches (1.2E12p) SiC screen T 0.001% S.Burger BE-BI-PM 29th June 2017 BI Day - Best Western/Chavannes de Bogis (CH)

During experiment with R4550 jaw target ! Beam measurements (without blocking foil) Screen: Alumina 1mm Filter NO Screen: Chromox 0.5mm Filter OD4 Screen: Ti 0.1mm Filter OD1 Screen: SiC 0.5mm Filter OD3 Single bunch (~1E11p) FP2_0.5mm 12bunch (~1.2E12p) FP2_0.5mm 72bunch (~7.2E12p) FP2_0.5mm 216bunch (~2.4E13p) FP2_0.25mm Screen: SiC 0.5mm Filter OD4 During experiment with R4550 jaw target ! 288bunch (~3.2E13p) FP2_0.25mm Screen to use VS beam type (intensity + optics) BE-BI MSWG 2017_07_07

Beam measurements (without blocking foil) Doubt on the beam sigma measured Always ~30% larger than the model (!?) σH,V<0.3mm Satellites Tails Measurements until Tuesday June 13th 18H27  give tails From Tuesday June 13th 18H43  give satellites If tails and satellites are not beam but ‘reflections’ or forward OTR from entrance vacuum window (expected negligible from Zemax simulations): work ongoing to define the source (mask, color filters, etc…) Some post processing to derive the real beam size (optics used 0.25 & 0.3) Plot from A.Fabich Plot from A.Fabich Satellites Error on beam size could be >11% Tails Error on beam size could be >35% [mm] [mm] BE-BI MSWG 2017_07_07

Viewport Vacuum window Air Vacuum Backward OTR from screen Reflection of forward OTR from vacuum entrance window  Contributes to enlarge the measurement Vacuum window Air Vacuum

Viewport Vacuum window Air Vacuum Backward OTR from screen Reflection of forward OTR from vacuum entrance window Reflection of forward OTR from ‘blocking’ foil ‘Superposed’ contribution Air Vacuum

Screens IN C foil (fixed) 75um Screen change in HRM BTV 2017_08_03 Beam Screens IN 2017_08_03 Screen change in HRM BTV Al2O3 replaced by new Glassy C Sigradur G Keep amorphous SiC even if broken to compare quality/sensitivity 288 bunches 0.25mm sigma traces on the C foil. Not holes yet but not far… SiC broken…

To do Need access to: check the ‘blocking’ foil Put a second camera (digital) with a beam splitter Get rid of the red filter Check focus Need beam time to: Measure with white light Scan measurement with OD filter (camera artefact with different S/N?) Scan the beam position on the screen (damage?)