Lecture 11 Complex Detector Systems 1
Dates 14.10. Vorlesung 1 T.Stockmanns 1.10. Vorlesung J.Ritman 8.10. Vorlesung 3 J.Ritman 04.11. Vorlesung 4 J.Ritman 11.11. Vorlesung 5 J.Ritman 18.11. Vorlesung 6 J. Ritman (Akad. Feier?) 5.11. Vorlesung 7 M.Mertens 0.1. Vorlesung 8 M.Mertens 09.1 Vorlesung 9 T.Stockmanns 16.1. fällt aus 3.1. Vorlesung 10 J.Ritman 13.01. Vorlesung 11 T.Stockmanns 0.01. Vorlesung 1 T.Stockmanns 7.01. Vorlesung 13 J.Ritman 03.0 Vorlesung 14 M.Mertens Besuch von COSY: 19. 3.1.
Content Semiconductor detectors Semiconductor basics Sensor concepts Readout electronics Scintillation detectors General characteristics Organic materials Inorganic materials Light output response Calorimeters Velocity Determination Cerenkov detectors Cerenkov radiation Cerenkov detectors Transition Radiation detectors Phenomenology of Transition Radiation Detection of Transition Radiation Time-Of-Flight Complex Detector Systems 3
Review of Lecture 10 Cherenkow Effect Transition Radiation 4
Review cos C 1 n with n n( ) 1 5
Review 6
Start of Lecture 11 7
Time-Of-Flight (TOF) 8
Time-Of-Flight l t c l p m t v l m p Time to Digital Converter TDC l l t t p p m m 9
Time-Of-Flight For l 1 m t 150 ps p/p 1 % 10
Time Difference particles (m 1, m ), momentum p length L p distance D relativistic particles E >> mc : E pc and development of square root non relativistic particles: 11
Time Difference time difference after 1 m time resolution 300 ps Kaon-pion separation up to 1 GeV/c for L = 3 m TOF limited for particles with p < GeV/c 1
TOF particle identification NA 49 particle multiplicity Belle mass from TOF measurement 13
ALICE (TOF) TOF with large multiplicity radius 3.6 m 150 m! scintillators too expensive gas detectors Multigap Resistive Plate Chamber (MGRPC) small gap good time resolution many gaps high efficiency Signal electrode Cathode -10 kv (-8 kv) (-6 kv) (-4 kv) (- kv) Anode 0 V Signal electrode resolution 50 ps 14
ALICE (TOF) 130 mm active area 70 mm Flat cable connector Differential signal sent from strip to interface card M5 nylon screw to hold fishing-line spacer connection to bring cathode signal to central read-out PCB honeycomb panel (10 mm thick) PCB with cathode pickup pads external glass plates 0.55 mm thick Honeycomb panel (10 mm thick) internal glass plates (0.4 mm thick) PCB with anode pickup pads 5 gas gaps of 50 micron PCB with cathode pickup pads Silicon sealing compound Mylar film (50 micron thick) 15
Combined Methods NA49 Particle identification by simultaneous de/dx and TOF measurement in the momentum range 5 to 6 GeV/c for central Pb+Pb collision m p l c 16 t l
Lifetime measurement - Tagging secondary vertex Identification of particles by their lifetime: e.g.: p 0.1 mm p D D 0 = 1040 10-15 s c = 31 µm = 410 10-15 s c = 13 µm Primary vertex Beam pipe B B 0 = 1671 10-15 s c = 501 µm = 1536 10-15 s c = 460 µm excellent vertex resolution needed! 17
Summary of PID techniques A number of powerful methods are available to identify particles over a large momentum range. Depending on the available space and the environment, the identification power can vary significantly. A very coarse plot. TR TOF de/dx RICH e ± identification Pion-Kaon separation for different PID methods. p/k separation The length of the detectors needed for 3s separation. 10-1 10 0 10 1 10 10 3 10 4 p [GeV/c] 18
Detector Systems 19
Detector Systems Detector Systems Remember: we want to have info on... number of particles event topology momentum / energy particle identity Can t be achieved with a single detector! integrate detectors to detector systems 0
Detector Systems Geometrical concepts Fix target geometry Magnet spectrometer Collider Geometry 4p Multi purpose detector target tracking muon filter N S beam magnet (dipole) calorimeter barrel endcap endcap Limited solid angle dw coverage rel. easy access (cables, maintenance) full dw coverage very restricted access 1
Detector Concepts Magnetic field configurations: solenoid B B toroid I magnet coil + Large homogenous field inside coil - weak opposite field in return yoke - Size limited (cost) - rel. high material budget Examples: DELPHI (SC, 1.T) L3 (NC, 0.5T) CMS (SC, 4T) I magnet + Rel. large fields over large volume + Rel. low material budget - non-uniform field - complex structure Example: ATLAS (Barrel air toroid, SC, 0.6T)
Detector Concepts Typical arrangement of subdetectors m + e - vertex location (Si detectors) p main tracking (gas or Si detectors) particle identification e.m. calorimetry magnet coil hadron calorimetry / return yoke muon identification / tracking 3
PANDA Spectrometer Detector requirements: 4p coverage (partial-wave-analysis) high rates (10 7 annihilations/s) good PID (, e, m, p, K, p) momentum res. (~1%) vertexing für D, K 0 S, L (c = 13 mm for D 0, p/m ) efficient trigger (e, m, K, D, L) event filtering (no hardware trigger) (raw data rate ~TB/s) 4
PANDA Spectrometer Interaction point Antiproton beam 1 m 5
PANDA Spectrometer Tracker MVD + STT + GEM 1 m 6
PANDA Spectrometer PID TOF + DIRC + RICH 13 m 7
PANDA Spectrometer Calorimetry EMC 13 m 8
PANDA Spectrometer Muon Detection 13 m 9
PANDA Spectrometer 13 m 30
This is the end of the lecture! Thank you for listening.