Stato del progetto RICH di LHCb

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Transcript Stato del progetto RICH di LHCb

Stato del progetto RICH di
LHCb
CSN1
Lecce, 24 settembre 2003
C.Matteuzzi
CSN1, Lecce 24/9/2003
LHCb RICH detectors
Particle ID over 1 – 100 GeV/c
provided by 2 RICH detectors
RICH2: No major changes
PRR in february 2003
Superstructure ordered
The first 10 mirrors accepted
Exit window being assembled
since RICH TDR
RICH1:
major design changes
included in new TDR
C.Matteuzzi
Motivated by :
the requirements for improved
L1 trigger
(0.15 Tm in tracking region)
Reduce material in the
spectrometer acceptance
CSN1, Lecce 24/9/2003
Rich-2 exit window
C.Matteuzzi
CSN1, Lecce 24/9/2003
Rich-2 exit window
C.Matteuzzi
CSN1, Lecce 24/9/2003
Impegni italiani nel RICH-2
Genova :
supporti
Milano:
schermo magnetico
consegna al CERN ottobre 2004
fotorivelatori
ottica (test, allineamento)
C.Matteuzzi
CSN1, Lecce 24/9/2003
RICH-1 Reoptimization
Reduced material within spectrometer acceptance:
– Light spherical mirrors
– Mirror supports outside acceptance
– RICH-1 entrance window removed, sealed
directly to the VELO tank
14% radiation length in TDR design
< 8%
B field for L1:
– Shielding of photon
detectors 600  25 G
C.Matteuzzi
CSN1, Lecce 24/9/2003
RICH-1: Material Budget
Item
% X 0 % lI
Entrance window
Aerogel
C4F10
Spherical mirror
Exit window
0.0
3.3
2.6
0.8
0.6
Total
7.3%
0.0
0.7
1.6
0.7
0.3
14% in TDR design
3.3%
C.Matteuzzi
CSN1, Lecce 24/9/2003
5% in TDR design
The vertical RICH-1
C.Matteuzzi
CSN1, Lecce 24/9/2003
The vertical RICH-1
The optics
C.Matteuzzi
CSN1, Lecce 24/9/2003
The radiators of RICH-1
1. Gas system (85 cm)
C4F10 no more available commercially
mix C3F8 and C5F12
(increase cost)
2. Aerogel (5 cm)
milestone LHCC in september 2003
C.Matteuzzi
CSN1, Lecce 24/9/2003
Aerogel radiator : the
final detector
A LHCC milestone (september 2003)
Parameters
n=1.030 (± 0.0002)
thickness 5 cm (tolerance 4 mm)
in 1 layer or 2.5+2.5 cm
clarity C< 0.0065 mm-4 (<0.0050)
transversal dimensions : 80x60 cm
Container
very light box (carbon fiber entrance + 0.1 mm D263 exit window)
2 parts splitting vertically
0.2 + 3.3 + 0.08 about 3.5 % X0
total weight ~ 4 Kg
Integration in RICH1 structure
to be finalized (supported by the superstructure) within the
drawings of Imperial College
C.Matteuzzi
CSN1, Lecce 24/9/2003
Aerogel radiator : the
final detector
A LHCC milestone (september 2003)
The tiles will be produced in Novosibirsk
(from June to December 2004)
tested (in parallel) and mounted
in 2004-2005 in Milano
detector ready as sealed boxes in June 2005
C.Matteuzzi
CSN1, Lecce 24/9/2003
RICH-1 Mirrors
•
Spherical mirrors
– 82 cm x 60 cm, R=240 cm: 1 per quadrant
– 2 technologies under study (decision by end 2003)
1. Carbon fibre: 2 mm thick
•
•
¼-scale prototype satisfies optical quality
Stability in fluorocarbon gas undergoing tests
2. Beryllium: 3 mm thick, with 0.3 mm glass coating
•
•
•
•
¼-scale prototpye satisfies optical quality
Compatible with flurocarbon gas
Higher cost than carbon fibre
Secondary plane mirrors (outside acceptance)
– 37 cm x 39 cm: 4 per quadrant
– Glass: 6 mm thick
C.Matteuzzi
CSN1, Lecce 24/9/2003
RICH-1: Performance
Number of photoelectron hits per ring
Cherenkov angle precision
Number of photon hits per trigger
In BB event
Contributions to Cherenkov angle precision
C.Matteuzzi
CSN1, Lecce 24/9/2003
Photodetector Technology choice
2 technologies considered:
Pixel HPD: LHCb development (+DEP,VTT)
83 mm diameter hybrid photodiode array
Silicon pixel sensor, bump-bonded to 40MHz readout chip
encapsulated in vacuum tube
Effective pixel size: 2.5mm x 2.5 mm
MaPMT: Hamamatsu M64 multianode PMT
Coupled to BEETLE r/o electronics (similar to LHCb Si trackers)
1760 tubes required in RICH-1
Quartz lens on each MaPMT to increase active area (48%)
Less stringent reduction of field (25 gauss instead of < 10 Gauss)
Magnification x 1.5 and effective pixel size is 3mm x 3mm
Switch to MaPMT baseline in June 2003
C.Matteuzzi
CSN1, Lecce 24/9/2003
Final Decision
for october 2003
Status of HPDs
Bump-bonding problem SOLVED
8 new assemblies delivered end of may
tested with Sr90, baked out and re-tested
No bump-bonding degradation
2 assemblies mounted at DEP in two 40 MHz HPDs
tubes and delivered 5/8/03
No bump-bonding degradation,chip operation OK,
tubes operated at 20 kV
NO PROBLEM
C.Matteuzzi
CSN1, Lecce 24/9/2003
Status of HPDs
• VTT informed on 20.5.2003 about the
presence of a crust on the bumps’ top prior
to flip-chip assembly. This most probably
explains why the above assemblies were not
optimal. The crust problem is understood
and solved.
before
C.Matteuzzi
After
CSN1, Lecce 24/9/2003
Status of HPDs
first of the two 40 MHz HPDs tubes
installed in T9 (PS beam) on 19/8/03
Cerenkov rings were recorded the same day
Both tubes successfully tested on the beam
preliminary laboratory tests, ageing
tests also OK
(detection efficiency 87%)
C.Matteuzzi
CSN1, Lecce 24/9/2003
•Cherenkov air
rings
•CO2 counter
@ 2.0bar
C.Matteuzzi
CSN1, Lecce 24/9/2003
Rings diameters
•2D histogram sliced
at weighted center
•Gaussian fits to the y
axis histograms
•Internal ring and
external ring
diameters on sensor
are determined
Int diam= 9.28 mm
Ext diam= 7.52 mm
C.Matteuzzi
CSN1, Lecce 24/9/2003
40MHz HPD: preliminary lab. tests
• LED measurements started (50ns strobe), back-pulse visibility
decreased (larger detector!, ie larger capacitance)
• Detection efficiency (first estimate): ~87%
(includes correction for long (250ns) back-pulse shaping time, LED
tail (4%) and non- working pixels (2%))
C.Matteuzzi
CSN1, Lecce 24/9/2003
Cluster Setup
Status of MaPMT
mounting holes
for
mount to vessel
5x boardBeetle
with Beetle 1.2
grounding points
8-dynode stage
MaPMT
HV point
slits to access
Cambridge
bleeder board rotation of 4 potentiometers
bleeder chains
mounting holes
for lens mount base plate for mounting and grounding
C.Matteuzzi
CSN1, Lecce 24/9/2003
First Spectra with boardBeetle
before CM correction
after CM correction
Beetle 1.2:
800V
=1.02
Beetle
1.2MA0:
800V
=0.55
Beetle 1.2:
800V
=0.77
Beetle
1.2MA0:
800V
=0.51
Beetle 1.2:
900V
=1.06
Beetle
1.2MA0:
900V
=0.55
Beetle 1.2:
900V
=0.78
Beetle
1.2MA0:
900V
=0.53
C.Matteuzzi
Saturation at half the dynamic range:
present before the FED!
CSN1, Lecce 24/9/2003
First Cherenkov Light
• 8 MaPMTs
– no lenses
– HV = 800 V
• Cherenkov Ring
– Air 960 mbar
– 3.6 pixels / event
with 5 sigma cut
– from raw data
C.Matteuzzi
CSN1, Lecce 24/9/2003
Cherenkov Rings
• Cherenkov photons, CF4 800mbar: 8-stage MaPMT, Beetle1.2;
with lenses, -900V
from raw data
with cross-talk cut on left or right
neighbour
10.3 photons/evt beam: -10 GeV  mostly -6.5 photons/evt
C.Matteuzzi
CSN1, Lecce 24/9/2003
Test will go on in october
RICH project costs (kCHF)
C.Matteuzzi
CSN1, Lecce 24/9/2003
Sharing of RICH cost
Before reoptimization
CERN
ITALY
UK
1016
1000
5674
Total cost
7690
C.Matteuzzi
After reoptimization
CSN1, Lecce 24/9/2003
9566
CORE Updated
Vessel and superstr.
220
Magnetic Shielding
Spherical mirror
CF (Be)
82
Plane mirror
Mirror supports
Photon detector supp.
Quartz window
Aerogel
C.Matteuzzi
380
(+160)
150
Quote from AKsteel
130(170) Lightweight mirror(+88)
CMA (Russia)
33 Based on RICH2 plane
mirror quote
55
94 Based on RICH2 plane
mirror supports(+39)
110
110
50
50
134
134
Additional photon
detectors and readout
Total
Comments
651
370
Increased focal length
of spherical mirrors
1491
(+840)
CSN1, Lecce 24/9/2003
Rich1
mechanics and
optics
Rich2
mechanics and
optics
Photon
detectors
Electronics
Services
C.Matteuzzi
Total
CORE Updated
647
1121
Comments
RICH-1 light +
magnetic shield
(+320 +150)
1203
1275
Mirror support
structure(+72)
3763
4104
HPD 
MaPMTs(+340)
1351
2276
730
790
Binary 
Analogue(+920)
Provision for
C3F8/C5F12 mix in
RICH1(+60)
(+1870)
CSN1, Lecce 24/9/2003
7693
9566
Spare slides
C.Matteuzzi
CSN1, Lecce 24/9/2003
The LHCb Detector
Reduced number of layers for M1 (4  2)
Reduced number of tracking stations behind the magnet (4  3)
No tracking chambers in the magnet
No B filed shielding plate
Changes were made for
Full Si station
material reduction and
Reoptimized
RICH-1
design
C.Matteuzzi
CSN1, Lecce 24/9/2003
L1 trigger improvement
Reduced number of VELO stations (25  21)
VELO
• 19 stations needed to cover the LHCb
acceptance ( > 3 stations / track)
+ 2 stations for robustness = 21 stations
Track loss for 2521=
0.1%, 2120 = 0.5%
CSN1, Lecce 24/9/2003
C.Matteuzzi
Prototype work advancing
Al window
C.Matteuzzi
CSN1, Lecce 24/9/2003
EDR planned for June 2004
Cost of the experiment
cf. MoU
VELO
IT
TT
OT
RICH
Calo
Muon detect.
Muon Fe
L0 Trig
DAQ&CPU farm
ECS&TFC
Computing infra.
Experiment infra.
Magnet
4.82
2.47
3.40
6.23
9.57
15.06
6.93
4.00
2.26
5.71
1.58
0.71
4.00
6.00
-0.28
MoU included VETO
+0.72
Now all Si TT*)
-3.86
+1.87
-0.30
-0.52
10  3 stations*)
New RICH1*)&MaPMT analogue cost
+0.06
With VETO
*) due to reoptimization
Increase of RICH1 mechanics from TDR = 492kCHF:
 B field shielding box, Be mirror, superstructure, etc.
C.Matteuzzi
CSN1, Lecce 24/9/2003
Total
cost = 72.74 MCHF
(-2.31 MCHF from the MoU cost)