1. Vertex Detector
Overview
Prototypes
R&D Plans
Summary

2. Radiation Environment
Including effects of walls, vessel
High doses at tips
(1/r2)
Dose after 1yr
1014
station 6
1 MeV equivalent neutrons/cm2
1013 cm

3. Technology Options for LHCb Vertex Detector
pro con
p strip Single sided processing Rapidly falling efficiency
Reduced cost (30%)and ease of handling below partial depletion
Minimum pitch 12 m High field region on opposite surface to readout
Thin detectors advantageous for Needs to be thinner for given
multiple scattering operating voltage.(Lower signal)
Handling(cost) of thin detectors.
n strip High efficiency at partial depletion gives Lithographic processing of back
lower operating voltage and lower power (Cost and handling)
High field region (after irradiation) at Minimum pitch 40m.
readout strips.
Operating partially depleted at tip still
allows full depletion (high CCE) elsewhere.
both Material Difficult to handle
Charge Correlation Offset voltages on one side of
detector for electronics.
Thermal contact - sensitive face?
Prototype
1998

4. Prototypes Design n strip (robust) Measured Performance
Immediate Plans

5. Design r-detectors r-measuring -measuring detectors detectors
5 ° “stereo” tilt
Both detectors utilize a double metal layer to readout inner strips whilst keeping electronics outside of fiducial.
-detectors
Detectors Fabricated by Hamamatsu

6. Detectors fabricated on 100mm wafer
inner radius 10mm
readout tracks
spaced 50m
-measuring
detectors
r-measuring
detectors

7. Detector Measurements
-detectors
r-detectors
200 60
Current nA
Current nA 40
100 20
volts
volts
300
500
400
200
Capacitance pF
300
Capacitance pF
200
100
100
volts
volts

8. Detectors with VA2 electronics (8-chips)
noise (2adc)
pedestal
(offset from 1700)

9. Source Test
Ru source
adc counts

10. Test Beam

11. Test Beam

12. VX-Beamtest Setup

13. Test Beam Cooled box fast electronic(CERN) irradiated detectors
Look at degradation
of performance

14. R&D Plans Design pn prototype Design full size protoype
Test beam April 1998
slow electronics
measure resolution,etc.
Irradiation 1998
Test beam September 1998
fast electronics
Test beam 1999
test of irradiated detectors
test of p-strip detectors
Design pn prototype
Design full size protoype
Evaluation of operating conditions
Design of Module
F/E electronics

15. Module Design Single Sided r and  module LHCbUK
Thermal Runaway
W/mm2 -4 -8
Temperature at Tip (°C)
LHCb
thick detectors
Single Sided r and  module
Thermal Model: hold cooling at -10°C

16. p-strip design

17. Modelling

18. Fast Electronics
SCT128a

19. RD39 Joint RD39 / LHCb / DELPHI Project
Charge collection possible from radiation damaged diodes at Liquid Nitrogen Temperatures
LHCb - interest
DELPHI
double sided detectors and MX readout

20. RD39/DELPHI/LHCb Test Beam
Chips work at low temperature
Module Mechanically stable
Irradiated to 4 X 1014 protons/cm2
Several thousand events collected
Temperature and bias voltage scans

21. Software LHCb will use C++ Test Beam Software Designed for future use
BUT Technical Proposal work was in FORTRAN
Test Beam
used to gain experience with new language and Root
All reconstruction software in C++
Cluster Making, Event Display, Track Fit, Alignment, Noise Studies...
Software Designed for future use
both useful code, and class design

22. Future Plans By end of 2000 perform beam test 1/2 Station LHC speed
Radiation Hard Electronics
In Vacuum
Technical Design Report by 2001
Detector Design
On-Detector Electronics Design