Super BABAR Plans & Status David B. MacFarlane UC San Diego & SLAC 2 nd Super B Workshop in Hawaii...
-
date post
20-Dec-2015 -
Category
Documents
-
view
219 -
download
3
Transcript of Super BABAR Plans & Status David B. MacFarlane UC San Diego & SLAC 2 nd Super B Workshop in Hawaii...
Super BABAR Plans & Status
David B. MacFarlaneUC San Diego & SLAC
2nd Super B Workshop in HawaiiApril 20, 2005
April 20, 2005 Super BABAR Status & Plans 2
Latest News from PEP-II & BABAR
First collisions in PEP-II early morning April 15 Began routine data collection with BABAR late
Monday nighto PEP-II delivered up to 4.8x1033 on Monday night; improving
rapidlyo LER and HER trickle injection operationalo Very fast start once collisions achieved; much faster than
previous Run 4 startup
BABAR & PEP-II are very pleased & excited to be back in the gameo Installed upgrades to PEP-II should allow at least 1.3x1034 o Upcoming run will extend through to July 31, 2006, with only
one month interruption in October for PPS certification
April 20, 2005 Super BABAR Status & Plans 3
Outline
Summary of PEP-II/BABAR study of scenarios for Super B Factoryo Try to give you a sense of the thinking behind our push to
very high luminosity
Developments at DOE and SLAC concerning future of PEP-II and Super PEP-II/BABAR opportunityo Substantial change in outlook at SLAC & a potential
opportunity to look at a collaborative effort on a Super B Factory
April 20, 2005 Super BABAR Status & Plans 4
BABAR Roadmap Study: Jan – July 04 Defining physics case for Super B Factory
o Primarily New Physics sensitivity in CP violation & rare decays
o Capability for precision SM measurements as benchmark for New Physics
Requirements of viable project planso Factor in duration of approval and funding processo Collider options and upgrade capabilitieso Detector capabilities & requirements in light of machine
parameters & projected backgroundso Integrated scenarios for collider and detector construction,
with implications for time to first data & competitiveness Projections of physics reach in light of
competition & other opportunitieso Projections of samples & sensitivities; analysis of physics
reach
April 20, 2005 Super BABAR Status & Plans 5
Physics Case for Super B Factory
Lots of work done, but everyone not convinced yeto Super B is not yet part of the US long-range planning for HEP
• National Academy study could change thiso Will compete with other physics opportunities in 2010-2015
• Most notably large-scale neutrino physics Case rests primarily on ability to explore flavor
physics couplings of New Physicso Complementary to hadron b experiments; perhaps natural
successoro Perhaps our data is already hinting at New Physics, which will
motivate further precision studies of flavor physics; perhaps LHC will see direct evidence for New Physics
• Physics case may very well strengthen with time Luminosity goals & physics timeliness a major
factor as well
April 20, 2005 Super BABAR Status & Plans 6
Constructing a Viable Plan
What is the timeline for approval process? What are the machine upgrade options?
o Components development and replacements requiredo Flexibility for further luminosity improvemento Timelines for construction and commissioning
What are the detector system requirements and options?o Limits of existing detector technologies due to backgroundso Modifications to existing technologies or possible alternatives
• Impact on physics performanceo Requirements for fundamental detector R&D
• Uncertainties can impact approval process
Fit together elements into a coherent set of options
April 20, 2005 Super BABAR Status & Plans 7
Parameters for High-Luminosity B Factory
Luminosity (x1034)
0.9 2.4 15 25 70 Units
e+ 3.1 3.1 3.1 3.5 8.0 GeV
e- 9.0 9.0 9.0 8.0 3.5 GeV
I+ 2.45 4.5 8.7 11.0 6.8 A
I- 1.55 2.2 3.0 4.8 15.5 A
(y*) 11 8 3.6 3.0 1.5 mm
(x*) 30 30 30 25 15 cm
Bunch length 10 7.5 4 3.4 1.7 mm
# bunches 1588 1700 1700 3450 6900
Crossing angle 0 0 0 11 15 mrad
Tune shifts (x/y)
4.5/7 8/8 11/11 11/11 11/11 x100
rf frequency 476 476 476 476 952 MHz
Site power 40 40 75 85 100 MWJ.Seeman Jul 04 Jul 07 LERvacuum
+IR +HER vacuum, 952MHz rf
April 20, 2005 Super BABAR Status & Plans 8
PEP-II upgrades schemes
Luminosity (x 1035)
1.5 2.5 7 57
RF frequency (MHz)
476 476 952 476952
Site power (MW)
75 85 100 70100
Crossing angle
No Yes Yes Yes
Crab cavities
No Yes Yes Yes
Replace LER Yes Yes Yes Yes
Replace HER No No Yes Yes
Upgradeable NoYes
(to 952MHz)Yes YesDetector requirements depend on projecting
backgrounds for luminosities that are >20 times larger than at present
Recommended
I II III IV
April 20, 2005 Super BABAR Status & Plans 9
Input from Detector Systems
1. Extrapolation of backgrounds with and without luminosity component; spatial and/or angular distributions if significant;
2. Performance degradation with occupancy and projected limits; likewise radiation damage and projected limits;
3. Any modest upgrades that will increase performance range or radiation tolerance;
4. Speculation about options for 5-10x1035 machines.
What are limits of current technologies?
Long extrapolation from current background studies, which include significant luminosity-
dependent component at PEP-II
April 20, 2005 Super BABAR Status & Plans 10
32.5
2 1.51
0.5
LER Radiative Bhabhas
-7.5 -5 -2.5 0 2.5 5 7.5
0
10
20
30
-10
-20
-30
m
cm
M. SullivanFeb. 8, 2004API88k3_R5_RADBHA_TOT_7_5M
3.1 G
eV
3.1 G
eV
9 GeV
9 GeV
Luminosity Dependent Backgrounds
M.Sullivan
Luminosity term
depends on IR design
April 20, 2005 Super BABAR Status & Plans 11
SVT Backgrounds: Bottom module
SVT Occupancy (Bottom)
0
40
80
120
160
200
240
8 200 700 1000Luminosity (10E33)
Oc
cu
pa
nc
y (
%)
100%
50%
20%
10%
0%
Lumi term
DANGER with 4x granularity increase
B.Petersen, F.FortiAssumes striplets increase granularity 4-fold
April 20, 2005 Super BABAR Status & Plans 12
Monolithic Active Pixels Option for very high luminosity is MAPS =
Monolithic Active Pixels = sensor and electronics on the same substrate.o R&D on MAPS started in several places, including Pisa
Possible approaches:o Integrate electronics on the high resistivity substrate
usually employed for sensors: 4 times thinner total material
• Active components are not of the best quality• The fabrication process is highly non-standard with
large feature size (>1-2mm)o Use the low resistivity substrate of standard CMOS process
as sensor• Can use standard sub-micron process with state-of-the-
art electronicsFar from a proven technology: fundamental R&D required
April 20, 2005 Super BABAR Status & Plans 13
DCH Occupancy Based on 2004 Studies
Based on 2004 Fits
0
20
40
60
80
100
120
7 33 200 700 1000
Lumi
HER
LER
Based on 2004 Fits
0
5
10
15
20
25
30
35
7 33 200 700 1000
20% Lumi
HER
LER
N_LER [%]
N_HER [%]
N_BEAM [%]
N_LUMI [%]
20% L [%]
N_DCH [%]
N_DCH [%] 20%L
0.7 1 6 7 3 1 10 73.3 2 9 11 15 3 26 1420 1 5 6 23 5 28 1070 2 7 8 79 16 87 24
100 2 10 12 90 18 102 30
4 x cells 4 x cells
M.Cristinziani
100% Lumi term
20% Lumi term
April 20, 2005 Super BABAR Status & Plans 14
Options for Beyond 2x1035
Basic configuration iso Leave SVT geometry unchanged; replace DCH with 4-layer
silicon tracker with lampshade modules. Remove support tube
o Radii of barrel part of SVT modules: 3.3, 4.0, 5.9, 12.2, 14.0 cm
o Radii of barrel part of CST modules: 25,35,45,60 cm
Current detector
60 cm
All silicon tracker
F.Forti
April 20, 2005 Super BABAR Status & Plans 15
Momentum Resolution
Central Silicon Tracker Performance
0.001
0.01
0.1
0 1 2 3 4 5 6
Ptot(GeV)
Sig
mak
(Gev
-1)
CST-100.300
CST050-nosupp
CST100-nosupp
CST100
CST200
CST300
CST300-small
S-DCH Present detecto
r
Future?
F.Forti
April 20, 2005 Super BABAR Status & Plans 16
EMC Background Projections
Integrated Luminosity
(2008) 1 ab-1
(2x1035) 10 ab-1
(1036) 100 ab-1
BackwardBarrel
0.88 0.78 X
ForwardBarrel
0.82 0.61 X
Endcap Small rings
0.82 0.69 X
Endcap Large rings
0.71 0.53 X
Degradation of light output with luminosity
Is this a functional
EMC?
Radiation Damage Projections
2x10
35
7x10
35
10
36
Versus ~8 physics clusters
Occupancy Projections
EMC lifetime limit: about 20 ab-1
April 20, 2005 Super BABAR Status & Plans 17
Radiation-Hard Calorimeter Options
Lutetium (+Yttrium) OxyOrthosilicate [LSO or LYSO]o Fast light output in 40ns; solves occupancy problem.o Smaller radiation length 1.15cm (CsI 1.86cm) and Moliere
radius 2.3 cm (CsI 3.8cm)o Believed to be radiation hard to 100MRad!o Currently cost is ~$40/cc; pushes radius towards 700mm
Liquid Xenono Fast light output again, within ~20ns. o Radiation length is 2.9cm: need all of radial space
between 700 and 1350mm for cryostat, liquid Xenon and readout.
o Moliere radius 5.7cm: long. sampling to separate overlaps. o Cost of Liquid Xenon is $2.5/ccBoth Rad Hard crystal and Liquid Xenon options require EMC inner radius reduction to about 70cm: need to replace DRC
bars as well
April 20, 2005 Super BABAR Status & Plans 18
Summary of Upgrade Options
LER replacement
1.5 2.5 5.0 7.0 x 1035
+ HER replacement
+ 952 MHz rf
SVT striplets
Thin pixels
CsI EMC
Rad Hard EMC+DRC bars
DRC SOB replacement
Wire chamber
Silicon outer tracker
[No x 2 for crabbing]
April 20, 2005 Super BABAR Status & Plans 19
Scenario 1: Detector Upgrades
Replace inner layers of present SVT with radiation hard upgrade
Replace DCH with small-cell version and faster gas
Replace DRC SOB Replace forward EMC Replace IFR forward endcap
April 20, 2005 Super BABAR Status & Plans 20
Scenario I
LER replacement
1.5 x 1035
SVT striplets
Wire chamber
CsI EMC
DRC SOB replacement
[No x 2 for crabbing]
April 20, 2005 Super BABAR Status & Plans 21
Scenario 2: Detector Upgrades
Replace inner layers of present SVT with radiation hard upgradeo Not much headroom with conventional strips
Replace DCH with small-cell version and faster gaso Drift chamber may not work at this luminosity and has no
headroomo More likely we would have to go to an all silicon tracker
Replace DRC SOB Replace forward EMC
o Barrel EMC has limited lifetime of a few years
Replace IFR forward endcap
April 20, 2005 Super BABAR Status & Plans 22
Scenario 2: Unlikely Solution
LER replacement
SVT striplets
Wire chamber
CsI EMC
DRC SOB replacement
2.5 x 1035[No x 2 for crabbing]
April 20, 2005 Super BABAR Status & Plans 23
Scenario 2: More Viable Solution
LER replacement
2.5 x 1035
SVT striplets
Silicon outer tracker
Rad Hard EMC
DRC replacement
[No x 2 for crabbing]
April 20, 2005 Super BABAR Status & Plans 24
Scenario 3: Detector Upgrades
Replace inner layers of present SVT with thin pixels
Replace DCH with all silicon tracker Replace DRC SOB and bar boxes due to
smaller radius for EMCo Not at all clear that DRC will work at these luminosities
Replace EMC with either radiation hard crystals or liquid xenon
Replace IFR forward endcapFundamental R&D for thin pixels drives approval schedule and overall timeline
Impossible to predict timeline for successful development
April 20, 2005 Super BABAR Status & Plans 25
Scenario 3
LER replacement
7.0 x 1035
+ HER replacement
+ 952 MHz rf
Thin pixels
Silicon outer tracker
Rad Hard EMC
DRC replacement
[No x 2 for crabbing]
April 20, 2005 Super BABAR Status & Plans 26
Scenario 4: Detector Upgrades
Replace inner layers of present SVT with segmented stripso Should be viable to about 5 x 1035
o Develop thin pixels and replace inner SVT at an appropriate time to go higher in luminosity
Replace DCH with all silicon tracker Replace DRC SOB and bar boxes due to
smaller radius for EMCo Not at all clear that DRC will work at these luminosities
Replace EMC with either radiation hard crystals or liquid xenon
Replace IFR forward endcap
April 20, 2005 Super BABAR Status & Plans 27
Upgrade Plan: Initial 5x1035
ProjectLER replacement
5.0 7.0 x 1035
+ HER replacement
SVT striplets
+ 952 MHz rf
Silicon outer tracker
Rad Hard EMC
DRC replacement
2.5
Performance limit
[No x 2 for crabbing]
April 20, 2005 Super BABAR Status & Plans 28
Upgrade Plan: Ultimate Reach
LER replacement
5.0 7.0 x 1035
+ HER replacement
SVT striplets
+ 952 MHz rf
Thin pixels
Silicon outer tracker
Rad Hard EMC
DRC replacement
2.5[No x 2 for crabbing]
April 20, 2005 Super BABAR Status & Plans 29
Important Factors in Upgrade Direction Project is “tunable”
o Can react to physics developmentso Can react to changing geopolitical situation
• Size of interested community, depth of financial support• Will emerge from BABAR and Belle, but could be attractive
to wider community in context of other opportunitieso As we learn more about machine and detector requirements
and design, can fine tune goals and plans within this framework
Project has headroomo Major upgrades to detector and machine, but none contingent
upon completing fundamental R&Do Headroom for detector up to 5 x 1035; with thin pixels beyondo Headroom for machine up to 8.5 x 1035; requires additional rf,
which can be staged into machine over time
April 20, 2005 Super BABAR Status & Plans 30
Possible Timeline for Super B Program
LOI
Construction of upgrades to L = 5-7x1035
-1~10 ab / yrLdt
Super-B Program
CDR Installation
R&D, Design, Proposals and
Approvals
P5
Construction
2001 2003 2010200820062005
Planned PEP-II Program
-1140 f bLdt -1500 f bLdt -1~1 2 abLdt
(June 30, 2003) (End 2006) (PEP-II ultimate)
Commission
2012
Super B Operation
2011
April 20, 2005 Super BABAR Status & Plans 31
0.00
0.02
0.04
0.06
0.08
0.10
0.12
0.14
0.16
0.18
0.20Ja
n-03
Jan-
04
Jan-
05
Jan-
06
Jan-
07
Jan-
08
Jan-
09
Jan-
10
Jan-
11
Jan-
12
Jan-
13
Jan-
14
Jan-
15
Jan-
16
Err
or
on
sin
e am
pli
tud
eProjections for Super B Factory
f0KS
KS0
KS
’KS
KKKS
K*
5 discovery region if non-SM physics is effect of 0.15
Super B Factory 5-7x1035 cm-2s-1
Projections are statistical errors only; but systematic errors at few percent
level
Luminosity expectation
s:
20122004
( ) 0.15S
Scale chang
e!
April 20, 2005 Super BABAR Status & Plans 32
0.00E+00
1.00E+03
2.00E+03
3.00E+03
4.00E+03
5.00E+03
6.00E+03
7.00E+03
8.00E+03
9.00E+03
1.00E+04
Jan-
03
Jul-0
3
Jan-
04
Jul-0
4
Jan-
05
Jul-0
5
Jan-
06
Jul-0
6
Jan-
07
Jul-0
7
Jan-
08
Jul-0
8
Jan-
09
Jul-0
9
Jan-
10
Jul-1
0
Jan-
11
Jul-1
1
Jan-
12
Jul-1
2
Jan-
13
Jul-1
3
Jan-
14
Jul-1
4
Jan-
15
Jul-1
5
Jan-
16
0.00
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
0.09
0.10
0.11
0.12
0.13
0.14
0.15
0.16
0.17
0.18
0.19
0.20
Comparisons: Projections for +-
(S) Lint
Eff
ecti
ve n
um
ber
of
tag
ged
even
ts
Err
or
on
sin
e a
mp
litu
de
SuperBLHCbBTEV
PEP-II, KEKB Super B-Factory 10/2011
April 20, 2005 Super BABAR Status & Plans 33
0.00E+00
5.00E+02
1.00E+03
1.50E+03
2.00E+03
2.50E+03
3.00E+03
3.50E+03
Jan-
03
Jul-0
3
Jan-
04
Jul-0
4
Jan-
05
Jul-0
5
Jan-
06
Jul-0
6
Jan-
07
Jul-0
7
Jan-
08
Jul-0
8
Jan-
09
Jul-0
9
Jan-
10
Jul-1
0
Jan-
11
Jul-1
1
Jan-
12
Jul-1
2
Jan-
13
Jul-1
3
Jan-
14
Jul-1
4
Jan-
15
Jul-1
5
Jan-
16
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
Projections for 2-Body Isospin Analysis
() Lint
Eff
ecti
ve n
um
ber
of
tag
ged
even
ts
Err
or
on
delt
a [
deg
rees]
SuperB
[Estimate: Summary of a range of errors depending on BFs,
asymmetries]
April 20, 2005 Super BABAR Status & Plans 34
0.00E+00
1.00E+03
2.00E+03
3.00E+03
4.00E+03
5.00E+03
6.00E+03
7.00E+03
8.00E+03
9.00E+03
1.00E+04
Jan-
03
Jul-0
3
Jan-
04
Jul-0
4
Jan-
05
Jul-0
5
Jan-
06
Jul-0
6
Jan-
07
Jul-0
7
Jan-
08
Jul-0
8
Jan-
09
Jul-0
9
Jan-
10
Jul-1
0
Jan-
11
Jul-1
1
Jan-
12
Jul-1
2
Jan-
13
Jul-1
3
Jan-
14
Jul-1
4
Jan-
15
Jul-1
5
Jan-
16
0.00
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
0.09
0.10
0.11
0.12
0.13
0.14
0.15
0.16
0.17
0.18
0.19
0.20
Projections for K*Eff
ecti
ve n
um
ber
of
tag
ged
even
ts
Err
or
on
sin
e a
mp
litu
de
PEP-II, KEKB Super B-Factory 10/2011
SuperB
April 20, 2005 Super BABAR Status & Plans 35
Developments at DOE Budgetary backdrop in US
o US domestic discretionary budget is under enormous pressure for the next few years at least: 5-year projections are for 3.7% decrease through to FY2010 in then year dollars
Priorities for US programo Highest priorities at present are full exploitation of Tevatron,
PEP-II, and LHC preparationso Intention is to make room for a new suite of mid-scale
experiments to be launched in 2007-2010 time frame, following ramp-down of PEP-II (2008) and Tevatron operations (2009)
• Focus is on accelerator and non-accelerator based neutrino, dark matter, & dark energy experiments
• Coherent plan for Fermilab as the national HEP laboratoryo ILC is the long-term highest priority for future major facility,
with US site the intended goal assuming international support
April 20, 2005 Super BABAR Status & Plans 36
Institutional Future of SLAC
Shift in institutional funding & focus 2006-2009o Major new $380M light source “LCLS” under construction
2005-2008: x-ray laser based on downstream 1/3rd of Linac• Additional beam lines later & use of full Linac (Stage 2)
o SLAC will become dual purpose laboratory• Roughly 2/3rd light science funded by DOE/Basic Energy
Sciences (BES), including entire Linac operation• Roughly 1/3rd HEP & particle-astrophysics funded by
DOE/HEP Consequences for future of PEP-II program
o FY2006 budget request by DOE foresees PEP-II operation only through to end of FY2008
o When PEP-II shuts down, there will be no longer be any machine operating for HEP on the SLAC site
• Major New Physics discovery might change this end date
April 20, 2005 Super BABAR Status & Plans 37
SLAC Planning for HEP
Plan presented by Jonathan to National Academy Long-Range Planning Committee in Januaryo Long-term priority is to play a leading role in the ILC,
independent of site• Follows guidance from SLAC scenarios studies• Follows strengths & technical expertise of lab• Follows SLAC’s long-term history of leading the push for
linear colliders, as well as priorities of the field and DOEo Full exploitation of the PEP-II B Factory program, including
physics output, through next decadeo Pursuit of an exciting & growing suite of possible astro-
particle physics experimentso Fill in behind the ILC long-term goal with a yet-to-be-
determined new accelerator-based project after PEP-II
April 20, 2005 Super BABAR Status & Plans 38
Consequences for Super B Factories Super PEP-II is not presently part of SLAC’s
long-range plano Does not fit with commitments to ILC & LCLS, or priorities
from DOE in tight budget situationo Could change depending on success of turning ILC into an
approved international project
Members of PEP-II & BABAR communities are starting to discuss future optionso Super KEKB is a possibility for a core part of PEP-II/BABAR,
depending on the strength of the physics case & competitiveness with other physics opportunities
o New participants could lead to expansion of scope for the Super B project and/or a more aggressive timescale
April 20, 2005 Super BABAR Status & Plans 39
Conclusion
Ideas for Super PEP-II/BABAR do not fit in SLAC plans at presento Reflects changes underway to SLAC’s scientific mission,
which is broadening in a big way into light science Core parts of PEP-II/BABAR are looking at
future options outside SLACo Early in a process of examining international accelerator-
based physics opportunities in the next decade, including Super KEKB
o Concerned about competitiveness & scope of Super KEKB; impact of planned peak & integrated luminosity goals on ability to convince international audience of the importance & viability of the project
o See this meeting potentially as part of a process of re-examining scope, assuming we factor in the possibility for additional US and/or European contributions to the project