LHC BIF test setup - update S. Mazzoni, 3/9/2018

BIF camera installation Camera installed in the LHC during 1st Technical Stop (18-21 June 2018) Optical setup (picture from final lab test) Pair of f = 300 mm achromatic doublets, 2in diameter Image intensifier Object plane Filter wheel (585, 340 nm) 11/2/2019

Target + 5 mm wrt reference BIF lab setup Overall magnification: 0.3 (0.6 at I.I. plane, then 0.5x relay lend to CMOS camera ). Equivalent pixel: approx. 20 um. => 15 pixel /sigma Images recorded with 585 nm filter at reference +/- 5 mm with 1 mm step for evaluating out-of-focus response Reference plane Target + 5 mm wrt reference 11/2/2019

THANKS TO THE BI-ML TEAM! LHC installation THANKS TO THE BI-ML TEAM! 11/2/2019

LHC installation 11/2/2019

Hot filament grid (BPC+40 mm) Alignment in the LHC Method: found image plane using the grid in front of the hot filament gauge. Then whole system move downwards of 40 mm (position of beampipe centre) End magnification: 0.34 Hot filament grid (BPC+40 mm) Beam pipe centre 11/2/2019

NO FLUORESCENCE SIGNAL VISIBLE Status Camera setup installed during TS1 (18-22 June) 3 data set acquired: 27/6: 1200b 6/7: 1500b 10/7: 2500b So far: NO FLUORESCENCE SIGNAL VISIBLE On 11/7 intensifier power supply malfunction. Access on 18/7, part removed from tunnel 11/2/2019

Data acquisition 27/6 Conditions: Fill 6854, 1227 bunches 6500 GeV 585 nm filter Gas pressure: “160” corresponding to roughly 3x10-8 mbar 450 images at 1s exp time, “640” int. gain 450 images at 6 ms exp time, “990” (max) int. gain No background images 11/2/2019

Dataset 27/6 Reference: hot filament gauge BG Red square: beam position Sum of 450 images, 1s exp time. Low int gain, no BG V profile on the side 11/2/2019

Dataset 27/6 Reference: hot filament gauge BG Red square: beam position Sum of 450 images, 6ms exp time. Max int gain, no BG V profile on the side 11/2/2019

Data acquisition 7/6 Conditions: Fill 6891, 1452 bunches 6500 GeV 585 nm filter Gas pressure: “170” corresponding to roughly 4-5x10-8 mbar 500 images at 1s exp time, “640” int. gain, BG (no gas) 500 images at 6ms exp time, “990” (max) int. gain, BG (no gas) 500 images at 6 ms exp time, “990” (max) int. gain Acquisition during injection 11/2/2019

Dataset 6/7 Reference: hot filament gauge BG Red square: beam position Sum of 500 images, 6ms exp time. Max int gain, BG subtracted V profile on the side Simulated BIF signal with equivalent conditions. Cross section: 4.7x10-22 cm2 TO BE CHECKED!!! 11/2/2019 BGC regular meeting

Data acquisition 10/7 Conditions: Fill 6909, 2556 bunches 6500 GeV 585 nm and 340 nm filter Gas pressure: “160” corresponding to roughly 3x10-8 mbar 500 images at 10 ms exp time, “990” (max) int. gain, BG (no gas), 585 nm 500 images at 10 ms exp time, “990” (max) int. gain, 585 nm 500 images at 10 ms exp time, “990” (max) int. gain, 340 nm Acquisition during injection 11/2/2019

Dataset 10/7 Reference: hot filament gauge BG Red square: beam position Sum of 500 images, 10ms exp time. Max int gain, BG subtracted V profile on the side 11/2/2019

Dataset 10/7 Reference: hot filament gauge BG Red square: beam position Sum of 500 images, 10ms exp time, 340 nm. Max int gain, no BG V profile on the side 11/2/2019

Intensifier camera malfunction On 11/7: intensified camera stopped working. Possible damage to the HV power supply. Part removed from LHC on 18/7 Not clear if malfunction must be linked to radiation damage. Same product installed in SPS since more than one year without issues (next slide) Intensifier is non radioactive, Will be shipped to Hamamatsu for repair Existing damaged (photocathode spot damaged by excessive illumination) spare from BSRT will be installed at next possible access (worst case: TS2, 27-31 August). Different photocathode (multialkali) 11/2/2019

SEU counts during injection Approx. 50 SEU during gas injection (approx. 2 hours) 11/2/2019

Summary No signal found so far. Discrepancy with simulations still under investigation Intensified camera will be re-installed by TS2. Radiation damage to electronics under investigation. A Radiation Monitor (TID, HEH) will be installed at on / next to the camera during TS2 11/2/2019

Alignment in the LHC All functional tests performed before TS end: Optical fibre link to CMOS camera Image Intensifier remote control Filter wheel motor control However, control PC not reachable today (to be investigated) 22/6/2018 BGC regular meeting