diamond beam conditions monitor for atlas (h. pernegger, cern)

H. Pernegger, CERN, RD42 coll. Meeting May 2004

Diamond Beam Conditions Monitor for ATLAS

(H. Pernegger, CERN)

H. Pernegger, CERN, RD42 coll. Meeting May 2004

People involved sofar from ATLAS Inner Detector

JSI, Ljubljana G. Kramberger, I. Mandić, M. Zavrtanik, V. Cindro, M. Mikuz

CERN H. Pernegger

Fotec, Wiener Neustadt E. Griesmayer, H. Frais-Kölbl

H. Pernegger, CERN, RD42 coll. Meeting May 2004

Part of the ATLAS Radiation Monitoring System

Instantaneous Beam Condition Monitor – BCM

Draft EDMS document ATL-IC-ES-0012

Integrating – on-line Total Ionization Dose - TID Non-Ionizing Energy Loss – NIEL Thermal Neutrons

EDMS document in preparation

Integrating – off-line TLD – not discussed today

H. Pernegger, CERN, RD42 coll. Meeting May 2004

ATLAS BCM goal

Goal of the BCM detector system inside the ATLAS Inner Detector

Monitor normal operation conditions Measure rate of collision Measure background rate close to vertex

Protection Detect early signs of beam instabilities Issue warning and alarm signals for equipment protect Input to ATLAS Detector Safety system and LHC beam abort

H. Pernegger, CERN, RD42 coll. Meeting May 2004

ATLAS BCM - beam loss scenarios

Simulations of beam orbits with wrong magnet settings (D. Bogdan) exhibit scenarios with beam scrapping TAS

Time constants of D1 & D2 dipoles large Can abort beam if detected early

H. Pernegger, CERN, RD42 coll. Meeting May 2004

ATLAS BCM during normal running

Time-Of-Flight measurement to distinguish collisions from back ground

Time difference

12ns

Need to measure single MIPs fast!

H. Pernegger, CERN, RD42 coll. Meeting May 2004

Timing of Hits on Collimators

2x4 detector stations, symmetric in zTAS events: Δt = 2z/cInteractions: Δt = 0, 25, … ns

H. Pernegger, CERN, RD42 coll. Meeting May 2004

CMS simulations of 7 TeV p on TAS

From M. Huhtinen

~ MIPs/cm2 per proton(ATLAS simulations by M Schupe in progress)

Zoom on ID

H. Pernegger, CERN, RD42 coll. Meeting May 2004

ATLAS BCM requirements

Distinguish TAS events from interaction events Installation at t = 12.5 ns -› z = 3.75 m Rise-time < 1 ns Pulse-width < 3 ns Base-line restoration < 10 ns

Single MIP sensitivity S/N for MIP’s 10:1 before irradiation

H. Pernegger, CERN, RD42 coll. Meeting May 2004

BCM installation in ATLAS Pixel Support

BCM mounting points

Pixel support tube: mid crucifix at z = 1838 mm, r > 100 mmDetectors to be mounted at 45 degrees

Cables: 4 mm coax up to PP1, 8 mm to USA15 HV, LV: custom Kapton insulated shielded TP Routing through single pixel phi sector/side

H. Pernegger, CERN, RD42 coll. Meeting May 2004

Detector 90Sr source test at CERN

90Sr sourcePb collimator

Diamond on support

Scintillator

Diamond detector w =470 µm, CCD ~ 200 µmHV Bias 1000 V

Different versions of FE electronics from Fotec 500Mhz (40 dB) (2 stages) 1 Ghz (60 dB) (3 stages)

LeCroy 1 GHz scope

H. Pernegger, CERN, RD42 coll. Meeting May 2004

Readout for characterization with fast current amplifier

Based on LabView

H. Pernegger, CERN, RD42 coll. Meeting May 2004

Diamond + electronics Tests in Testbeam MIP signal (testbeam & Sr90 source)

after 16m of cable perpendicular to beam, double diamond assembly Rise time 900ps, FWHM = 2.1ns

SNR = 7.3:1

H. Pernegger, CERN, RD42 coll. Meeting May 2004

Preliminary Detector & Electronics Tests: Sr90

MIP signal in CDS 113 Perpendicular Tested with

source in Lab Results: “ENC” = 1400 e- SNR = 5.4:1

H. Pernegger, CERN, RD42 coll. Meeting May 2004

Amplifier radiation test in Ljubljana

Tested 1 stage of 1 GHz amplifier (20dB)( test of 500MHz just started)

Bi-polar InGaP transistorIrradiated to Φeq = 1, 5, 10 x 1014 n/cm2 in reactor

Verdict:Amplifier still usableafter 1015 n/cm2

H. Pernegger, CERN, RD42 coll. Meeting May 2004

BCM Logic SchemeADC-> Intensity

TDC->TOFWarning/Alarms

H. Pernegger, CERN, RD42 coll. Meeting May 2004

Finalizing design of FE-end part Continue with diamonds back-to-back assembly & amplifier

irradiation Finalize required diamond material parameters Optimize amplifier design (S/N 10:1)

Started to look at Integration aspects Mounting of detector + FE electronics Design of readout logic

ATLAS BCM Next steps