Intrumentation HEL powering interlocks HEL main parameters today

Intrumentation, HEL powering, interlocks

HEL main parameters today Parameter Proton beam optics at HEL, Length of interaction, Value or range b [m] 280 L [m] 3 Desired transverse scraping (3 to 6 beam s), r [mm] 1. 1 – 2. 2 @ 7 Te. V 4. 3 – 8. 6 @ 450 Ge. V (note that here geometric emittance = 3. 5 umrad) Electron beam current, I [A] 5 Cathode diameter [mm] 8 to 16 Gun extraction and modulation voltage [k. V] 10 Cathode-ground voltage [k. V] 15 Collector voltage [k. V] in study Modulator rise time [ns] 200 Modulator repetition rate [k. Hz] 35 Magnetic field at gun [T] 0. 35 @ 7 Te. V to 4 @ 450 Ge. V Magnetic field at bend [T] 3. 5 Magnetic field at main [T] 3 @ 450 Ge. V to 5 @ 7 Te. V A. Rossi, International Review of the HL-LHC Collimation System, CERN, 11 -12 February 2019 2

The system configuration ward ected dir orce F s line x u l f netic lly in radia g ory aject e e tr in -r Mag HL-L HC E-gun solenoid ons prot 00 ~ 40 mm BPMs integrated in vacuum chamber Main solenoids Collector Checking for diagnostics at collector room for BGC monitor Electrons are produced by the cathode of an e-gun. A system of superconducting solenoids cooled at 4. 5 K generates the magnetic field to tune de size and steer the trajectory of the electron ring. D. Perini, 8 th HL-LHC Collaboration Meeting, CERN, 15 -18 October 2018 3

Beam Gas Curtain Monitor § Beam-Gas Fluorescence on target gas curtain § Looking at Ne and Ar as gas § Prototype to be installed in LHC Nitrogen gas jet test Moveable gauge measurement of the gas jet. This will be smaller in the interaction chamber. Courtesy of R. Veness, T. Dodington, H. Zhang, S. Udrea and BGC collaboration 8 th HL-LHC Collaboration meeting, 15 -16 October 2018 IBIC 2017 § Scaled version to be designed A. Rossi, International Review of the HL-LHC Collimation System, CERN, 11 -12 February 2019 4

BPMs § BPMs integrated in the vacuum chamber at the beginning of the first mail solenoid and at the end of the second. § First draft design to fit in space available § E-beam measurement: § for the moment we assume that it will work on the ramp-up or rampdown of the e-beam = 200 ns ramp during p-beam gaps § Circulating (p or ion) beam measurement: as in LHC § Questions still open: § Accuracy of relative positions considering that electronics will be different for 2 measurements. § Required 70 um (sigma at 7 Te. V = 0. 36 mm) 5

HEL schematics Electron gun (A) (8 -16 mm cathode) Modulator (35 KHz) Instrumentation BPMs Collector Overlap/transverse profile monitors BGC Gun solenoid (0. 3 to 4 T) Bending SC solenoids ~3. 5 T Main SC solenoids 3 to 5 T 6

Collector Electron gun 5 Ax 15 -20 k. V VCA Cathode Heater 10 Ax 40 V cathode grid anode + Control electrode -2 +2 k. V x 40 m. A – + + Anode modulator – VCA≤ 20 k. V, Ianode 35 k. Hz, 200 ns rise time – – Cathode PC + Anode modulator -3 KV VCO Anode/grid modulator 40 MHz High voltage (15 -20 k. V) low current (losses) VCA, Itube – Cathode – Collector PC -15 k. V repeller + High voltage (~15 k. V) High current VCA-VCO, Ibeam=5 A 0 -10 k. V 7

Location of new HEL in LHC Ring (P 4) HEL(B 2 e) HEL(B 1 i) ST 0676534_01 B 2 B 1 RB 44 RA 43 D 3 L 4 HEL(B 1 i) ACS ADT UJ 44 UA 43 19/10/2017 UL 44 US 45 1764989 v. 3 8 M. Gonzalez de la Aleja, Paolo Fessia A. Rossi, International Review of the HL-LHC Collimation System, CERN, 11 -12 February 2019 8

HEL integration in LHC M. Gonzalez de la Aleja, Paolo Fessia ST 0676534_01 . The beam to beam distance is 420 mm. The longitudinal available space is limited. Compact design 6