1# BaBar Overview & Plans Hassan Jawahery, spokesperson University of Maryland PEPII MAC Meeting...
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Transcript of 1# BaBar Overview & Plans Hassan Jawahery, spokesperson University of Maryland PEPII MAC Meeting...
1#
BaBar Overview & Plans
Hassan Jawahery, spokesperson University of Maryland
PEPII MAC MeetingNovember 15-17, 2007
2#
BaBar Upgrade: Completed the upgrade of the Instrumented
Flux Return (IFR)- replaced RPC’s with 12 layers of LST’s & 6 layers of brass in each of the remaining 4 sextants (2 sextants were done in 2004). Have fully recovered muon and KL identification capabilities of the detector.
Run 6: January 19– Sept. 4, 200790/fb delivered & 86/fb recordedwith the total of BaBar data at ~477.45/fb
Analysis of Runs 1-5 data set (390/fb)
Major Activities of the Collaboration
3#
A typical (good) day of BaBar running with PEPII
BaBar continues to collect most of PEPII delivery (dead-time typically at <2%)-crucial to keep this- Improvement in data-flow for SVT, DIRC, EMC have been implemented.
Data taking in 2007
4#
Are we ready for higher luminosity• Machine-Detector issues covered by M. Weaver
yesterday:The detector can withstand the “expected” radiation level &
the rise in the occupancy at some (but small) cost to the performance.
• Data Flow & Trigger:– Worked on reducing L1 trigger rate, transmitted data rate and
readout out time. (Run 6 averages: L1:2.65 KHz, & dead time 1.8%).
DCH: In Run 5, upgraded the front end electronics to reduce the transmitted info. Working well and no longer an issue.
SVT: Readout time window narrowed by ~27%, chip threshold adjustment & left- right readout.
DIRC: readout time reduced with newly cleaned up readout code. EMC: data flow rate reduced
Added a new trigger line (1E)- single energy cluster >800 MeV; Covers Y(nS)(invisible)- light Higgs & dark matter candidates; Level 3- Energy Threshold of 2 GeV. Adds around 12% to Level-1 trigger.
Emergency L1 trigger developed- to be deployed if needed.– We are OK up to ~7 KHz of level-1 trigger rate.
5#
6#
7#
Run Strategy The primary focus of the program continues to be on running at
the (4S) for this final run.
We are considering other opportunities for a part of the run:
New Trigger: single photon trigger (1E) added at the end of run 6. Covers Y(ns) invisible) – low mass higgs & dark matter
candidates,..
Running on narrow resonances; (3S) is emerging as the favorite place.
Search for b & other resonance physics. Measuring invisible decays of (1S), thru (3S) (1S)
cascade. Search for light higgs or dark matter candidates.
With about 2 weeks of running we will have six times the current data on (3S).
Running on (5S) for Bs physics(??) Needs lots of data to be useful.
We are working on optimizing the amount of off-resonance running - - may reduce it from the current 10%.
8#
Computing the BaBar data• Online data collection and processing in good
shape.
• Some challenges in the offline computing infrastructure at SLAC- progress being made to secure resources for processing run 7, and reprocessing runs 1-6.
– Have developed the final event reconstruction code- aimed for the “the best code possible” for our final processing of the data. The outcome is Very close to the goal.
– Now in the validations phase.
– Will be ready for run 7; Normally reprocess the 1st month, expect to happen February 1st; Also aiming for final reprocessing of runs 1-6 –starting around April 1.
9#
BaBar Performance
10#
Muon ID capability fully restored with the upgraded IFR (better in fact)
LSTLST
11#
-
4S)
B0
B0
D-
+
+
K-
e+
+z
e-
Overall performance measured with Oscillation in Dileptons
00 BB
12#
e+
+
0SK
e—
—
z
(4S)
0CPB
J/
00 BB
tags,, Ke
00 BB Overall performance measured with Oscillation with
fully reconstructed B’s
00 BB
13#
BaBar Physics
14#
BaBar Data: Runs 1-5
BB x100.4~ 9
cc x100.5~ 9
x100.4~ 9
ISR
qq e e
& -
Partial composition of the dataBaBar collects
~97% of PEP II delivery
15#
The physics reach of the BaBar Data
Just about any physics that is
accessible at
Charm Physics
Tau physics
Continuum e+e- hadrons
ISR: e+e- hadrons from threshold to ~5 GeV
GeVs 10
CP Studies with B’s
& B Physics
• Origin of CP breaking
•Test CKM paradigm
•Constraints on New Physics possibilities
D0 Mixing; New States,FDs
New States: DsJ, Y(4260), etc
Lepton Flavor Violation
Measuring the hadronic part of photon vacuum polarization
16#
A look at the timeline of our data collection vs our physics output
•There are more than 200 ongoing analyses of BaBar data.
•More than 317 papers published & submitted for publication.
17#
New Major Physics results Since last MAC (06)
• Oscillation observed
• Completed the picture of semileptonic B decays with the observation: &
• New States
00 DD
*DB DB
18#
mixingParticleAntiParticle Evidence for the missing pieces of the
puzzle
Already seen for :
)()( 00 dbBdbB
)()( 00 dsKdsK )()( 00 ucDucD
)()( 00 sbBsbB
The responsible processes :In the Standard Model
An opportunity for New Physics
Particles to contribute
WWZW
W c0D
cu
u0D0D 0D
O(10-3 - 10-2) O(10-5)
19#
Charm physics with Search for D0 mixing – highly suppressed in SM- a powerful window
for NP searches
A little bit of History from Fall 2006
cc x100.4~ 9
Observables:
CP even state: width , massm1 ;
CP odd state: width , massm2
y = -
x = (m1 – m2) / = m /
Last summer
from BaBar
In 2006 it looked like the Limits were approaching the SM expectation
20#
The BaBar observation of D0 mixing
(t) exp(-t) R + R y’ t + ¼ ( x’2 + y’2 ) t2 (t in units of D )
Identified about 1 million D0 K-RS) decays & 4000 D0 K+WS)
Found evidence for ~500 that had switched to anti-D0 before decaying
%31.044.097.0
%021.0030.0022.02
y
x
21#
D0 KK
D 0 KK 0 + c.c.D K
= 409.3 ± 0.7 fs
t (ps)
t (ps)
t (ps)
t (ps)
= 401.3 ± 2.5 fs = 404.5 ± 2.5 fs
(stat. errors only, syst. errors cancel largely in the lifetime ratios)
99.9% signal
70,000 KK events99.6% purity
31,000 events98.0% purity
K and KK lifetimes differ!
0 0,D D K0D KK0D KK
0D
0D
D0 lifetimes
Now also measured in decay time measurements
22#
23#
B Physics [with the ] 109 BB
Investigation of CP violation in B meson Decays & tests of the CKM paradigmIs the CP symmetry broken in B decays?Can we fit the CPV effects in the CKM picture?
Is there room for New Physics?
Search for New Physics in rare (SM suppressed-FCNC) decays ?
B Decays dynamics: Tests of QCD predictions
The “B physics” reach of the BaBar Data
BB x100.4~ 9
24#
109--
1982-B meson observed
1987-B0 mixing & Vub measured; Lower bound on m(top)>42 GeV; with non-zero Vub, CKM in the game as a source of CPV
1993-Radiative penguin bs observed; Major constraint on models of New Physics;Rare decays BK and obserevd; Role of gluonic penguins established;
B factory projects launched.
1999- B Factories start operation.
2001- CPV in B decays observed. Sin2 consistent with SM
The 1/ab phase: Precision tests of the CKM paradigm- Search for N.P. using loop dominated B decays, LFV tau decays, DD(bar) mixing …
Precision sin2; & measured; CKM over-constrained and established as the primary source of observed CPV in nature. Data consistent with no NP effects in b-d and sd.
108--
107--
104--
105--
106--
#B’s
A brief history of major milestones in B physics
25#
Tests of the CKM Paradigm
Picture from A. Hoecker
Theorist view of CKM Observables The view from the experiments
02.0)2sin
8)
105)
%5|)
o
o
ubV
Now
~7%
~20o
~10-15o
~0.04 (~1o)
Aiming for:
26#
A major focus of the experiment is now on searches for New Physics via FCNC decays of B- Deviation from SM searched for:
d
bR
tL
bL
WsL
L
Possible New Physics presence can alter the observables from SM expecations
b ss
sd
g
, ,u c t
W
There is more than just rate in these channels now:
•Photon polarization in bsL ( left-handed in SM)
•Direct CP violation – nearly zero in SM
•In BKll- q2 dependence of the rate; FB asymmetry, polariztion
Search for NP modification of Wilson coefficients C7, C9, C10
Sin2test in Penguin
dominated modes
27#
Simple average: Spenguins=0.56 +/- 0.05 vs reference point: sin68+/-0.03
~ 2.5 deviation at this point.
Latest on Sin2test in Penguin dominated modes-
Our other 2-sigma effect
28#
Observation of B → D(*)
Confirmation of Belle observation in D*+, first
observation of D*0 and first evidence for the D modes
(B → D)/(B → Dl)
arXiv:0707.2758
29#
New States found at the B factories (Summary from E. Eichten)
Candidates for new QCD states: Hybrid (cgc), Molecules(DD)....
30#
The BaBar Collaboration
October 17, 2006
31#
Russia [1/10]Budker Institute, Novosibirsk
Spain [2/7]IFAE-BarcelonaIFIC-Valencia
United Kingdom [11/58]U of BirminghamU of BristolBrunel UU of EdinburghU of LiverpoolImperial CollegeQueen Mary , U of LondonU of London, Royal Holloway U of ManchesterRutherford Appleton LaboratoryU of Warwick
USA[34/256]
California Institute of Technology
UC, IrvineUC, Los AngelesUC, RiversideUC, San DiegoUC, Santa BarbaraUC, Santa CruzU of CincinnatiU of ColoradoColorado StateHarvard UU of IowaIowa State UJohns Hopkins ULBNLLLNLU of LouisvilleU of MarylandU of Massachusetts, AmherstMITU of MississippiSUNY, AlbanyU of Notre DameOhio State UU of OregonPrinceton USLACU of South CarolinaStanford U
Canada [4/23]University of British ColumbiaMcGill UniversityUniversity de MontréalUniversity of Victoria
France [5/40]LAPP, AnnecyLAL OrsayLPNHE des Universités Paris VI et VIIEcole Polytechnique, Laboratoire
Leprince-RinguetCEA, DAPNIA, CE-Saclay
Germany [6/31]Ruhr Universitaet BochumUniversitaet DortmundTechnische Univeritaet DresdenUniversitaet HeidelbergUniversitaet RostockUniversitaet Karlsruhe
The BABAR Collaboration
10 Countries 77 Institutions522 Physicists
+21 non-Physicists
Italy[12/90]
INFN, BariINFN, FerraraLab. Nazionali di Frascati dell'
INFNINFN, Genova & UnivINFN, Milano & UnivINFN, Napoli & UnivINFN, Padova & UnivINFN, Pisa & Univ & Scuola
Normale SuperioreINFN, Perugia & UnivINFN, Roma & Univ "La
Sapienza"INFN, Torino & UnivINFN, Trieste & Univ
The Netherlands [1/3]
NIKHEF, Amsterdam
Norway [1/4]U of Bergen
U of TennesseeU of Texas at AustinU of Texas at DallasU of WisconsinYale
32#
Status of the Collaboration
77 Institutions in 10 countries
The collaborations is on a very strong foundation
With 154 students and 89 postdocs, BaBar continues to be a major educational institution as
well
Faculty PhD Staff Postdoc Grad Non-PhD Totals
Canada 10 1 4 8 23
France 13 14 3 10 4 44
Germany 7 5 3 16 1 32
Italy 29 30 11 20 90
Netherlands 1 2 3
Norway 2 2 4
Russia 2 7 1 1 11
Spain 2 2 3 7
United Kingdom 21 2 16 19 2 60
United States 79 54 50 73 13 269
Totals 164 115 89 154 21 543
One of the few remaining
institutions for training future HEP physicists for the
LHC & ILC era
33#
The Manpower needed to operate the experiment
BaBar’s technical coordinator (Bill Wisniewski) has determined that it takes ~ 110 of collaboration-FTE to operate (Detector maintenance and calibration, and computing tasks- excluding the technical and computing professionals) to operate BaBar. This also does not include the data taking shifts.
System managers have done detailed planning for coverage of the tasks till end of the data taking-e.g. for SVT:
34#
Planning for BaBar in 2008 & BeyondAnalysis of the final data set
35#
Guided by the need for timely performance of the key measurements that define the scientific mission of the program:
Precision knowledge of the Standard Model is an extremely important element of the search for “New Physics” in the (LHC) era, with the B factory data largely in charge of the flavor sector– “Textbook” measurements of the CKM sector are expected to emerge.
Processes involving loop effects are expected to help in understanding the nature of the results that may emerge from LHC. To be relevant these measurements must be available on the same time scale.
The key players in the analyses effort are the postdocs and graduate students, whose life span in the experiment is a major factor in defining the time window required for performing these measurements.
A period ~2-3 years of intense analysis activity, following the end of the data taking, in order to perform and publish the core physics channels.
2009-2011
Given the very broad physics reach of the “1/ab” data, the full exploitation of the physics will take much longer- LEP/SLC/CLEO experiences points to an overall 5-8 year program
The planning of BaBar in 2008 & Beyond(cont’)
36#
A list of topics on BaBar’s “core”
physics program
The ultimate job on CKM – until the SuperB era
The
no-stone-unturned search for New
Physics
37#
Summary remarks The near-“1/ab” phase of BaBar is here:
The LST installation, the last major detector upgrade, has successfully been completed & the muon Id capability of BaBar fully restored for the run 6 and run 7 data.
The collaboration is healthy with a strong base of students and postdocs.
An intense-analysis period of 2-3 yrs is expected to follow the end of the data taking period, requiring continued major support for the experiment.
An enormous amount of physics still to come from Flavor physics with BaBar in this phase. Two of the expected major outcomes are: Precision knowledge of the charge weak sector of the SM & the CKM
parameters; The CKM part of SM is still under construction (expt’s wise)With the possibility of revealing deviation from the SM
Measurements of CP violation and decay properties in rare decay modes, with the possibility of revealing New Physics effects. Hints are already present in the current data.
BaBar is continuing to serve as a major institution for educating future High Energy Physicists who will work on LHC and ILC.
38#
The BaBar community is truly grateful to our PEPII colleagues for their outstanding and dedicated effort in creating the principal
element of this enterprise.