RD42 Meeting, CERN W. de Boer, Univ. of Karlsruhe 1 CVD diamonds as beam monitors CVD diamond used for: heavy ion beam monitor beam exit window for primary beams (heat spreader material?) Beam Loss Monitor for CMS

RD42 Meeting, CERN W. de Boer, Univ. of Karlsruhe 2 Pb 67+ up to 2,5*10 9 Ions pro bunch. Here bunch split into 4 sub-bunches Diamond as beam monitor

RD42 Meeting, CERN W. de Boer, Univ. of Karlsruhe 3 Diamond signal [V] Beam transformer [mV] Bunch of 2*10 8 Oxygen ions with beam transformer and diamond strip detector 500ns Time resolution in sub ns range

RD42 Meeting, CERN W. de Boer, Univ. of Karlsruhe 4 Beampipe (Vacuum) Target (Xenon, 14 bar) Diamond (300um) Flange Diffusion Bonding Diffusion Bonding: Metallization GND HV+Signal Diamond can be bonded to metal Beam Contact

RD42 Meeting, CERN W. de Boer, Univ. of Karlsruhe 5 Simple sensor design proven in beam Diamond diffusion bonded in metal vacuum flange Advantages: no hybrid needed radiation hard mechanically robust Al-metallization done without masks Guard ring = diffusion bond [ns] Left: signals from cyclotron showing the 26 MHz bunches. Each bunch has about 10 6 protons, so the signal can be directly displayed on the scope without amplifier, even with 10m cable. Width given by spread in bunches diamond signal Vacuumwindow Solderpin for cable 1 cm 40 ns [V]

RD42 Meeting, CERN W. de Boer, Univ. of Karlsruhe 6 IP BCM1 BCM2 “heat spreader” CVD diamond radhard tunnelcard LHC ionization chambers for beam loss monitoring Beam loss at KA cyclotron LHC beam loss and background Monitoring at CMS

RD42 Meeting, CERN W. de Boer, Univ. of Karlsruhe 7 Beam test with BCM electronics for LHC (developed in Bernd Dehning’s group at CERN) 8 channel tunnel cards with optical fiber output 40 us sampling time 16 channel VME readout cards

RD42 Meeting, CERN W. de Boer, Univ. of Karlsruhe 8 CFC Card – working principle Principle: after reset: C is discharged with detector current. To continuously check the card an additional current source of 10 pA discharges as well, so at least every 20s a trigger will be given to a counter indicating that C was discharged below the threshold. Every 40 us the counter on the board is readout telling how many times the capacitor was discharged, which is a measure of the sensor current. Additionally an ADC converts the integrator voltages into digital values which can be used to calculate the slope of the discharge and therefore the current, this is important for low detector currents. ADC values

RD42 Meeting, CERN W. de Boer, Univ. of Karlsruhe 9 CFC-Card USB readout electronics diamond KAZ Karlsruher cyclotron 26MeV protons current to frequency converter range: 10pA – 1mA low-noise readout radiation hard design Test at KA cyclotron sensor signal versus time

RD42 Meeting, CERN W. de Boer, Univ. of Karlsruhe 10 5=5scans 36cm 4=4scans 29cm 3=3scans 31cm 2=2scans 38cm 1scan System Test at cyclotron in Karlsruhe

RD42 Meeting, CERN W. de Boer, Univ. of Karlsruhe 11 Beam Condition Monitoring at LHC BCM at LHC is done by roundabout 3700 gas ionization chambers which are placed round the ring if their signal gets too large a beam dump is requested to prevent a quenching of the superconducting magnets or damage on the machinery there is no space inside the 4 caverns for this chambers, so another solution was needed to monitor the beam without interruption For CMS this is the BeamRadiationMonitoring System consisting of 6 subsystems of which 3 are diamond based and places inside the CMS detector BCM2 consists of 16 (opt 32) pCVD diamonds, which are placed near the beam pipe the readout of BCM2 is solely based on the same electronics as the gas ionization chambers, so the data is immediately available via the LHC software

RD42 Meeting, CERN W. de Boer, Univ. of Karlsruhe 12 Tunnel card with CFC from LHC Beam Monitoring Group (Dehning, Effinger) Layout CMS Beam Loss Monitoring

RD42 Meeting, CERN W. de Boer, Univ. of Karlsruhe 13 BCM2 sensor pCVD 350µm 10x10mm mounted in a box of aluminum for shielding metalization visible from both sides contact with bond wires and silver epoxy glue CMS sensor from Bob Stone, Rutgers metalization: Tungsten-Titanium measured CCD: 250µm HVSignal

RD42 Meeting, CERN W. de Boer, Univ. of Karlsruhe 14 Decrease of CCD vs fluence with 26 MeV protons

RD42 Meeting, CERN W. de Boer, Univ. of Karlsruhe 15 ZIons NIEL Total GeV protons ZIon NIEL Total Radiation damage in Diamond n p Si elastic Si inelastic Si total C total C elastic C inelastic Si C 200 MeV

RD42 Meeting, CERN W. de Boer, Univ. of Karlsruhe 16 BCM2 Z=± 14.4m, r=29cm BCM1 Z=± 1.9m, r=4.3cm BSC Z=± 1.9m, r=4.3cm Fibre Based Radiation Monitors Cherenkov Fibres Radiation monitoring components

RD42 Meeting, CERN W. de Boer, Univ. of Karlsruhe 17 Charged particle flux at BCM1 ~ 1x10 7 cm -2 s cm -2 per BX Neutron flux at BCM1 ~ 1x10 7 cm -2 s cm -2 per BX High neutron flux for BCM2 CMS Flux Maps

RD42 Meeting, CERN W. de Boer, Univ. of Karlsruhe 18 TOTEM T2 IP TOTEM T1 HF Plug BCM Sensor Carriage+ BCM1 BSC Scintillators (On front of HF) BCM2 Sensors Fibre loop Fibre Coils CMS Rad mon RADMON BCM1 and BCM2

RD42 Meeting, CERN W. de Boer, Univ. of Karlsruhe 19 Tracker Bulkhead BCM1 Carriage Pixel Rail System Beampipe BCM1 BCM1: Mechanical Structure

RD42 Meeting, CERN W. de Boer, Univ. of Karlsruhe 20 Beam Energy Tracking Beam Dumping System DCCT Dipole Current 1 DCCT Dipole Current 2 RF turn clock LHC Beam Interlock System Access Safety System Beam Dump Trigger SPS Extraction Interlocks Injection Kickers essential circuits auxiliary circuits Safe LHC Parameters Beam Current Monitors Current Energy SafeBeam Flag Energy TL collimators Timing PM Trigger BLMs aperture BPMs for Beam Dump LHC Experiments Collimators / Absorbers NC Magnet Interlocks Vacuum System RF + Damper dI/dt beam current BLMs arc BPMs for dx/dt + dy/dt dI/dt magnet current Operators Software Interlocks Screens Powering Interlock System Quench Protection Power Converters Discharge Switches AUG UPS Cryogenics Machine Protection Systems and Interfaces