1. The LHCb Upgrade Chris Parkes Why Upgrade ? Trigger System
Radiation Hard Vertex Detector
Thanks to my LHCb Collaborators
for advice/results/speculations…
Vertex 2005, November 2005, Nikko
VElo Superior Performance Apparatus

2. Dedicated B System CP violation Experiment
Full spectrum of B hadrons:
Bs system,All angles, sides of both CKM s
Lots of events ! p
250 mrad
10 mrad
Vertex Locator
Dipole magnet
Tracking system
Calorimeters
Muon system
RICH detectors

3. R / Phi measuring sensors
Velo Rôles
Primary / b decay Vertex reconstruction
Stand alone Tracking
A principle tracking device for the experiment
Second Level Trigger
Fast tracking 1m
R / Phi measuring sensors
In vacuum
Retract each fill
Align each fill
One set of half disks

4. Yet another B-Factory ?
LHCb - Dedicated B physics experiment at LHC designed for precision study of CP violation and rare decays
BTeV Cancelled
BaBar Closure forseen
Super-Belle ?
Likely to be only B-Factory in LHC era
LHCb  now 47 institutes in 16 countries > 600 authors
But what is left to do after the B-factories?

5. What Did the 1st Generation
B-Factories Do For Us ?
Spectacular progress from the B-factories: Baseline measurement ACP (J/y KS) Agreement with Standard Model CKM
Impressive range of additional measurements
Significant
constraints
on 
95% CL

6. Some Puzzles left by the B factories…..
New physics in b s ?
sin 2bb  s = sin 2bb  c?
see in Bs  f f ?
increased BR for Bs  m+m- ?
Higher frequency Dms ?
Larger CP violation in Bs  J/y f
Bs–Bs oscillation
Dms as Standard Model
CDF or D0 measure ?
If beyond SM…
LHCb VELO / trigger required
dms > 14.5 ps-1    xs > 21.1 (95% CL)

7. After 3 Years of LHCb….. 3 Years of LHCb data taking
Bs mix
3 Years of LHCb data taking
1 day at LHCb = 100d at B Factory !
In event rate but hadronic environment….
Bs Oscillations measured
SM <25 ps-1, CDF
LHCb ms reach 68 ps-1
 measured
Theory error ~1% will be matched by LHCb ~ 5yrs
 measured J/ K0
theory error < 1%, 1 yr statistical error sin(2) 0.02
LHCb: st = 43 fs

8. Limited by Statistics. B Physics after 2010
(What will NOT be known after 3 years of LHCb running ?)
Precision Gamma (< 5 degrees)
Theoretically very clean, error only ~ 0.1% !
etc.
“Tree” only
New Physics in D mixing?
Improved vertex
Resolution equiv.
to more stats
Limited by Statistics.
Rare B-decays
The other Triangle….
BsJ/
SM BR at most 3.5x10-9 !
5 events per 2 fb-1 (S/N 3:1)
Weak mixing phase 
Proper-time resolution important
8 independent parameters to determine
SM BR at most 1.5x10-10 !!
Requires upgrade

9. But NOT Limited by LHC Pile-up at high luminosity Defocus LHC beams
Limited by Statistics.
Number of pp interactions/ beam crossing
Pile-up at high luminosity
B mesons identified by
separation of primary interaction
vertex and decay vertex
(few mm)
Displaced Vertex trigger
2nd level of triggering
Multiple Interactions
Limit Event reconstruction
Defocus LHC beams
ATLAS/CMS 1034 cm-2s-1 but LHCb 2x1032 cm-2s-1
 most events have single interactions
Could LHCb cope with higher Luminosity ? 1033 cm-2s-1
Extreme Radiation Environment in VELO

10. Increase Luminosity – Trigger System
LHCb would have to cope with multiple interactions
Existing 1st Level Trigger
Veto on multiple
interactions !
Trigger based on:
High pT Muons
& calorimeter clusters
Trigger on BsJ/KK
5 X Yield
Number of
Triggered
Events
4 X Yield
1st Level Trigger Rate (MHz)
3 X Yield
2 X Yield
Std. Yield
4 of 10 benchmark LHCb
channels have +- in final state
Luminosity (x1032)
Enhanced Rare B-decay Programme WITHOUT Trigger upgrade
Radiation Damage, Occupancy

11. Hadron Channel Trigger
Trigger on BsJ/KK
1.8 X Yield
Hadron Channel Trigger
High ET Trigger not sufficient
Std. Yield
1st Level Trigger Rate (MHz)
Number of
Triggered
Events
1st Level Displaced Track Trigger
Latency 4s, 2s for data processing
Luminosity (x1032)
Massive use of FPGAs can allow us to make a Vertex trigger in ~2010
BTeV assumed they could do this in 2009
(though 132 ns not 25 ns)
Need pt information ?
Magnetic Field in VELO or include other silicon stations

12. Pile-Up Veto System Two planes of R-measuring sensors
Identical to VELO sensors
Placed up-stream from interaction point
Strips ORed in groups of 4
Mbit/s links per hybrid
Optical links to rad-free barracks
FPGA processing performed

13. Pile-Up Veto: Principle
Tracks from same ZPV have the same ratio k
RA ZPV - ZA
RB ZPV - ZB
k  = RA
ZPV’ k’ ZB ZA RB
ZPV
B A k
Silicon Sensors (backward!)
Histogram combinations
Find peaks
(Zvtx)  2.8 mm
(beam)  53 mm
Primary Vertex 1
Primary Vertex 2

14. Displaced Vertex Trigger
Current 2nd Level Trigger algorithm performed in CPU Farm
2D Tracking
2D rz VELO tracking
Tracks from beam line form straight lines in rz
Primary Vertex search
2D track selection
3D Tracking
3D rfz VELO tracking
Add info. From Phi measuring Sensors
Only for displaced track candidates
3D confirm
L0 m match
3D IP
VELO-TT matching
Add PT Information
Use silicon stations after magnet
p, pT estimation
L1 decision
Total: 1ms not 2s !

15. System Configuration Outline R projection only
Tasks 8
Clustering &
Triplet finding &
merging
Track
Identification &
filtering
In Radiation Free zone
4 sectors per half
Track merging
Two halfs
Vertex identification
Impact parameter calculation
Final vertex trigger decision
35 processing modules
2 crates
2200 optical links
36 multi ribbon cables (8x8)

16. Extreme Radiation Environment
LHCb VELO will be HOT!
Maximum Fluence
1.3x NIEL 1 MeV neq/cm2/year at 8mm
3.3x NIEL 1 MeV neq/cm2/year at 5mm
6.6x NIEL 1MeV neq/cm2/year at 8mm at 1033
Strongly non-uniform
dependence on 1/r2 and station (z)
Middle station
Far station
VESPA needs
1015 neq/cm2 charged
particle tolerance

17. Radiation Damage: When replace VELO?
Testbeam results, Simulations
System components
specified to 500V
Confident to run to 300V
Maintain a reasonable
S/N performance
6fb-1 (3-4 years) at 300V

18. Radiation Hard Technologies
Cz, n-on-p, 3D, or pixel technologies –
Active R&D, with RD50
Czochralski
n-on-p 3D
Extreme rad. hard
For 4.5 x GeV p/cm2
Depletion voltage = 19V !!!

19. Strips or Pixels? Both potentially rad. hard
3D, Cz, n-on-p or hybrid pixel detectors
Pixels better pattern recognition properties
Not major problem (Velo trk eff 97.3%, ghosts 2.3%)
But could be trigger advanatge
Require approx. 50 m2 pixels
Achieve same resolution as Velo
Strip geometry more `natural’
Tesselate, strixels
But if you can read-out the pixels who cares ?
Material
Less pixel layers (not R/Phi)
Detector, Chip and services (cooling)
X0 per layer 1.2% (BTeV), 1.7% (CMS), 1.8% (ATLAS)
Thin electronics, typically 500m, achieve 200m
BTeV

20. 5mm limit from Accelerator
Move Closer
5mm limit from Accelerator
Current safe guard ring design 1mm
Edgeless technology exits
Dope edges
etch, laser cut
Sensor Design
with 5mm active
radius
Baseline first strip 8mm
7.1mm 10% improvement in IP
Impact Parameter
Simulation
RF foil removed
VELO Inner radius 5 mm
36% improvement !
Resolution (microns)
8mm VELO
5mm VELO

21. Material Budget: RF-foil
Total: 19%Xo
VELO RF-foil 250m
BTeV
BTev - 150m thick wires/foil, 6mm from beam
In primary vacuum
Cryo panels for absorb outgassing
TOTEM
1mm from beam (v. diff optics)
150m foil

22. Prototype in LHC ! Four free station slots available
Equipped with cooling tubes
Can Prototype in the LHC !
Add extra tracking points, and small amount of extra material

23. Conclusions Rich Physics Programme for LHCb after 2010
1 st Upgrade at LHC, Increased lumi.
Necessitated by radiation environment
FPGA based Displaced Vertex Trigger
at 1 st Level of Triggering
VElo Superior Performance Apparatus
Radiation tolerant Si technologies
RF foil redesign
Reduce material, Move closer to beam
Thus the Vespa came to be linked in my eyes with transgression, sin, and even temptation…. And it entered into my imagination not as an object of desire, but as a symbol of an unfulfilled desire." - Umberto Eco