The
Detector
Francesco Forti,
INFN and University, Pisa
F.Forti - SuperB Detector
1
Detector

Babar and Belle designs have
proven to be very effective for BFactory physics




Follow the same ideas for SuperB
detector
 Try to reuse same components as
much as possible


Main issues
Machine backgrounds – not much
larger than in Babar/Belle
 Beam energy asymmetry – a bit
smaller
 Strong interaction with machine
design



Some areas require moderate R&D
and engineering developments to
improve performance



A SuperB detector is possible with
today’s technology


Baseline is reusing large
(expensive) parts of Babar (or
Belle)
 Quartz bars of the DIRC
 Barrel EMC CsI(Tl) crystal and
mechanical structure
 Superconducting coil and flux
return yoke.


Small beam pipe technology
Thin silicon pixel detector for first
layer
Drift chamber CF mechanical
structure, gas and cell size
Photon detection for DIRC quartz
bars
Forward PID system (TOF or
focusing RICH)
Forward calorimeter crystals (LSO)
Minos-style scintillator for
Instrumented flux return
Electronics and trigger – need to
revise Bfactory “½-track” trigger
style
Computing – large data amount
More details in:


F.Forti - SuperB Detector
www.pi.infn.it/SuperB/node/159 - SuperB
Italy Meeting on detector R&D
indico.lal.in2p3.fr/conferenceDisplay.py?
confId=167 – Paris workshop (May 9-11)
2
Detector Layout – Reuse parts of Babar (or Belle)
BASELINE
OPTION
F.Forti - SuperB Detector
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SuperB Detector R&D

Overall goals of detector R&D organization:
 Advance
the R&D activity as coherently as possible,
without duplication of effort and covering all relevant
issues
 Start creating the infrastructure and doing the work
needed for a Technical Design Report (time scale 1-2
years)
 Create the software infrastructure to perform
simulations and physics studies for the optimization of
the detector design
 Prepare the ground for the formation of a collaboration
(time scale 1 year)
 Provide a structure to prepare funding applications
 Provide and entry point for new groups wishing to join
F.Forti - SuperB Detector
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R&D Organization

Detector R&D Co-conveners

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Subsystems R&D conveners, tentative, open.
Hopefully more than one convener per system

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

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F.Forti, B.N.Ratcliff
MDI – Calderini
SVT – Rizzo +
DCH –
PID – Leith +
EMC – Hitlin +
IFR – Calabrese +
Electronics –
Trigger/DAQ –
Computing – Morandin +
Testbeams coordinator
Software coordinator
F.Forti - SuperB Detector
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Groups interests and activities
System
Italiani
SVT
PI, PV-BG, TO, MI, TS, (BO, PG,
RM3)
DCH
LNF, (LE)
PID
PD
Stranieri
Maryland
Triumph, SLAC
SLAC, Ljubljana, BINP, Orsay?
EMC
PG, RM1
Caltech, UK, Germany?, Canada
IFR
FE, PD, RM1
Ohio?
Trigger/DAQ
BO, NA, TO
SLAC + US
Computing
PD, FE, TO, BO, PI
SLAC + US, UK, Germany ?
Software
RM2, FE?, PI, RM1
F.Forti - SuperB Detector
......
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Backgrounds

Dominated by QED cross section
 Low
currents / high luminosity
Beam-gas are not a problem
 SR fan can be shielded

F.Forti - SuperB Detector
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We have an IR design coping with main BKG source
SuperB Interaction Region
20
Radiative BhaBha
B0H
10
B0L
QF1
QD0H
B00H
B00L
QD0
QD0
QF1
cm
0
3.5
-10
2
3
1.5
1
0.5 1
1.52 3
QD0H 4
2.5 3.5
0.5
4.5
5
6 6.5
2.5
QF1
QF1
-20
-3
5.5
B0H
B0L
-2
-1
0
m
1
2
3
M.Sullivan
M.Sullivan
Nov.
Nov. 13,
13, 2006
2006
SB_IT_ILC_G3_300
SB_IT_ILC_G3_300
Need serious amount of shielding to prevent the produced shower
from reaching the detector.
F.Forti - SuperB Detector
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Asymmetry and beam pipe radius

Lower boost advantegeous for machine design



8 + 3.5 βγ=0.45
we can afford to have a lower boost only if the vertexing
resolution is good:



Babar: 9 + 3.1 βγ=0.56 , Belle:
SuperB: 7 + 4 βγ=0.28
small radius
beam pipe
very little material
in b.p. and first layer
Vertex separation significance
<Dz>/s(Dz) vs bg
A b.p. with r ~1cm
is highly desirable
Present Babar value
F.Forti - SuperB Detector
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Beam pipe
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1.0 cm inner radius
Be inner wall

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8 water cooled channels
(0.3mm thick)

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Power ≈ 1kW
Peek outer wall
Outer radius ≈ 1.2cm
Thermal simulation shows
max T ≈ 55°C
Issues


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≈ 4um inside Au coating
Connection to rest of b.p.
Be corrosion
Outer wall may be required
to be thermally conductive
to cool pixels
F.Forti - SuperB Detector
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SVT
20 cm
Layer0
30 cm

Baseline: use an SVT similar to
the Babar one, complemented
by one or two inner layers.



40 cm
Question on whether it would
possible/economical to add a
layer between SVT and DCH,
or move L5 to larger radius
Cannot reuse because of
radiation damage
Beam pipe radius is paramount


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inner radius: 1.0cm,
layer0 radius: 1.2cm,
thickness: 0.5% X0
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SVT SuperB R&D

Two options for SuperB SVT Layer0
design in CDR:
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Basic MAPS R&D (sensor & electronics) partly included in the SLIM5 project
(GRV-PRIN)
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Striplets option: well established
technology, less robust against
background occupancy.
CMOS MAPS options: more robust
against background occupancy but
extensive R&D needed.
Test of the prototype thin tracker (striplets and MAPS) in a test beam in 2008
Some aspects of Layer0 design from CDR (system/mechanical aspects) are
not covered in SLIM5 (details in next slide)
People involved in the project:


SLIM5 group: PI, PV/BG,TS, T0, (TN), BO
MI (BaBar+Citterio/Alimonti/Coelli) just joined the effort. + RM3
F.Forti - SuperB Detector
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DCH

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Basic technology adequate.
Cannot reuse BaBar DCH
because of aging
Baseline:

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
Same gas, same cell shape
Carbon fiber endplates instead
of Al to reduce thickness
 Need to do complete
background estimate
Attività 2008 a LNF
Options/Issues to be studied:

Miniaturization and relocation
of readout electronics
Critical for backward
calorimetric coverage

Conical endplate
Further optimization of cell
size/gas

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simulare dettagliatamente i fondi
attesi nella camera, e studiare con
Garfield configurazioni di cella e
miscele di gas alternative
Testare le nuove miscele e geometrie
di cella su un piccolo prototipo di
camera a drift
costruire un tracciatore compatto con
risoluzioni spaziali O(50μm)
estrapolate nel prototipo di camera,
da usare anche alla Beam Test
Facility (BTF) dei LNF (e± da 500
MeV/c).
F.Forti - SuperB Detector
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Particle ID

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Barrel PID essential for hadron PID
above ~0.7GeV.
DIRC baseline

Quartz bars are OK and can be
reused
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Almost irreplaceable
PMTs are aging and need to be
replaced
Keep mechanical support
Barrel Options

Readout options motivated by
reduction of background generated
in SOB
 SOB: Faster PMTs using the
standoff box and water coupling
 Smaller SOB: Pixilated MaPMTs
and fused silica coupling
 No SOB: Focusing readout with
pixilated MaPMTs
Already active groups:
SLAC, Ljubljana, BINP
Attività a PD
Test di PMT e SiPM
F.Forti - SuperB Detector
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Forward/Backward PID option

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Extending PID coverage to the forward
and backward considered
Possibly useful, physics case needs to be
established quantitatively
Serious interference with other systems

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
cause displacement of front face of EMC
require miniaturization and displacement
of DCH electronics

2+2cm aerogel
TOF seems the only viable option
Technologies
 Aerogel-based focusing
RICH


4cm aerogel single index
Material in front of the EMC
Needs space


Focusing configuration – data
May 10, 2007
SuperB V
Peter Križan, Ljubljana
Working device
Requires significant space
(>25 cm)
Time of flight

Need about 10ps resolution
to be competitive with
focusing RICH
 15-20ps OK. 10ps seems to
be achievable, although not
easy
F.Forti - SuperB Detector
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EMC

Barrel CsI(Tl) crystals

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Still OK and can be reused (the most expensive detector in
BaBar)
Baseline is to transport barrel as one device

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Forward Endcap EMC
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Various other transportation options
BaBar crystal are damaged by radiation and need to be replaced
Occupancy at low angle makes CsI(Tl) too slow
No doubt we need a forward calorimeter
Backward EMC option

Because of material in front will have a degraded performance
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Maybe just a VETO device for rare channels such as Btn.
Physics impact needs to be quantitatively assessed
DIRC bars are necessarily in the middle
DCH electronics relocation is critical for the perfomance
Active group in CALTECH
(Ren-yuan Zhu)
Attività a PG + RM1
Test di PMT e SiPM
F.Forti - SuperB Detector
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Forward EMC crystals

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Both pure CsI and LSO could be used in
the forward EMC
LSO more expensive, but more light,
more compact, and more radiation hard
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Use LSO as baseline
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Now LSO is available industrially
Cost difference still significant, but not
overwhelming.
Gives better performance
Leaves PID option open
CsI option still open

in case of cost/availability issues
Baskward calorimeter
 Keep as an option
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Could be less performant
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Backward endcap
Barrel extension
Lead – scintillator ?
Benchmark physics gain
F.Forti - SuperB Detector
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IFR and steel
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BaBar configuration has too
little iron for m ID

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> 6.5 lI required; 4-5
available in barrel
Fine segmentation overdid
KL efficiency optimization
Focus on m ID : fewer
layers and more iron
  Is it possible to use the
IFR in KL veto mode ?

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Baseline:

Fill gaps in Babar
IFR with more iron
 Leave 7-8 detection
layers
 Need to verify
structural issues
 Scintillator bars à la MINOS because rates in the
100Hz/cm2 range

Cost effectiveness of steel reuse needs to be fully
assessed
F.Forti - SuperB Detector
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IFR
Cavoto
Attività a FE, PD, RM1

Studi sulle fibre WLS:
 Tipo di fibra: circolari o quadrate ( eff.
Intrappolamento 30% maggiore)
 Vari diametri (0.8, 1.0, 1.2 mm) e
concentrazioni (150, 175, 200 ppm)
 Velocita’ di risposta: Kuraray-T11 (≈10
ns), Saint-Gobain-BCF 92 (≈2.7ns)

Studi sui vari tipi di scintillatore:
 Numero di fibre minimo per la raccolta di
una quantita’ sufficiente di luce
 Forma dello scintillatore: rettangolare con
solchi in superficie o interni (co – estrusi)
Studi e misure sui SiPM/MPPC:
 Verifica di: Guadagno, dark counts rate,
stabilita’ del guadagno vs V and T
 Studi di invecchiamento: curva
caratteristica I0-V, guadagno, dark counts
misurati periodicamente (qualche giorno)
dopo esposizione del dispositivo a luce
verde
 Test di irraggiamento
 Misura della variazione dei vari
parametri per diversi dispositivi

Prime misure su sistemi completi scintillatore
+ fibra + photodetector con raggi cosmici/ test
beam:
 Quantita’ di luce, efficienza di rivelazione,
risoluzione temporale/spaziale
F.Forti - SuperB Detector
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Electronics and Trigger/DAQ

L1 Trigger rate of 100-150KHz

Unless a hardware Bhabha rejector
is developed
 Up from 5KHz current Babar rate

Some electronics could be reusable

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The bulk of the electronics is
obsolete and unmaintainable

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Especially front-end cards, maybe
power supplies
Should be remade with state-of-theart technology
Clearly a major cost driver

Costed using recent experiments
experience (LHC)
Attività a BO + NA
Requirements
Architecture
L1 buffer
FPGA based
Trigger
Control
L1 accept
Detector
FE
Optical links
L1 Trigger
L1
Buffer
F.Forti - SuperB Detector
L3 Trigger
IP Datagram
L3
Trigger
Farm
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Computing

Computing model
extrapolated from Babar

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Scales with luminosity
Requires distributed
computing on the grid
Attività in FE, PD, TO, BO, PI
• valutazione risorse di calcolo e infrastrutture
di un centroTier0 per SuperB
• definizione e supporto di un insieme di
strumenti collaborativi
• supporto alle attività della VO SuperB in Grid
• organizzazione delle risorse di calcolo per il
TDR
F.Forti - SuperB Detector
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The SuperB Process
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International SuperB Study Group on

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International steering committee established, chaired by
M.A.Giorgi. Members from

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Physics case, Machine, Detector
Canada, France, Germany, Italy, Russia, Spain, UK, US
Regular interaction with Japan, although not formalized
Regular workshops
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Five workshop held (2 in Frascati, 1 in SLAC, 1 Villa
Mondragone, 1 Paris)
SuperB Meeting at Daresbury
Accelerator retreat at SLAC in 2006
Accelerator Retreat at SLAC Sep 17-21, 2007

Conceptual Design Report

Ready, printed and distributed.
 Describe Physics case, Accelerator, Detector, including costing
 International review ongoing
More information: www.pi.infn.it/SuperB


http://www.pi.infn.it/SuperB/seminars
F.Forti - SuperB Detector
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CDR Ready !!!!
The CDR of SuperB is
ready!
INFN/AE-07/02,
SLAC-R-856,
LAL 07-15
Available at:
www.pi.infn.it/SuperB
arxiv.org/abs/0709.0451
476 pages
Printed and available
Copies can be requested
from [email protected]
F.Forti - SuperB Detector
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Signatures: some numbers

320 Signatures; 85 institutions
Drop Page Fields Here
Signatures breakdown by country

174 Babar members

65 non Babar exper.
Australia, 1
Canada, 7
Experimentalists
75%
Signatures
Theorists
13%
USA, 70
France, 21
Germany, 11
Israel, 2
Accelerator
physicists
12%
UK, 24
Switzerland, 4
Spain, 12
Slovenia, 5
Italy, 137
Russia, 18
ROC, 3
Norway, 1
Japan, 4
Signatures breakdown by type
Signatures
by country
Dropbreakdown
Series Fields Here
F.Forti - SuperB Detector
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CDR Review

An International Review Committee has been appointed by INFN.

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The review is scheduled for Nov 6-7, 2007.
A first report is expected end 2007
The final report foreseen in spring 2008


After the results of the LNF test of crab waist foreseen in fall 2007
Already presented to ECFA in the summer


John Dainton – UK/Daresbury, chair
Jacques Lefrancois – F/Orsay
Antonio Masiero – I/Padova
Rolf Heuer – D/ Desy
Daniel Schulte – CERN
Abe Seiden – USA/UCSC
Young-Kee Kim – USA/FNAL
Hiroaki Aihara – Japan/Tokyo
Very positive reaction
Presentation to the CERN strategy group foreseen in spring 2008

Coordinates all projects in european HEP for research infrastructure

INFRA-2007-2.2.1.33: Projects in the European strategy for particle physics
(CERN Council)
F.Forti - SuperB Detector
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