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P. Wittich1
Peter Wittich
University of PAMarch 1, 2002
From Solar Neutrinos to B Physics: Flavor
Oscillations at SNO and CDF
P. Wittich2
SNO CDF
Goals Solar problem Many (B physics is small part)
Beam Divine (solar) e Tevatron ppbar
Detection Medium
Heavy water Si, ArC2H6, Scintillator, …
Channels ~104 ~106
Energies 4-15 MeV ~ 10 GeV
Event rate 10 Hz 7.6 MHz
S/N 10 events/day Depends…
Physics Flavor oscillations Flavor oscillations
At the base, the same physics!
What ties these two experiments together?
P. Wittich3
Flavor Oscillations
1
1
1
12
-)1(A
22-1
)(A2
-1
UUU
UUU
UUU
1212
1212
1313
1313
2323
2323
23
22
32
333231
232221
131211
massflavor
cs
sc
ces
esc
cs
sc
Ai
A
i
U
U
i
i
1
1
1
12
-)1(A
22-1
)(A2
-1
UUU
UUU
UUU
1212
1212
1313
1313
2323
2323
23
22
32
333231
232221
131211
massflavor
cs
sc
ces
esc
cs
sc
Ai
A
i
U
U
i
i
Wolfenstein: CKM
PDG “standard”: MNS
P. Wittich4
Solar Neutrino Problem
Bahcall
Bahcall
Most plausible solution: flavor oscillations in ’s
P. Wittich5
SNO DetectorSNO Detector
1 kT virgin D2O
~ 10,000 PMTson 16.8 m support (LBL!)
7 kT H2O, ultrapure
Penn ElectronicsControlRoom
Urylonliner
2039 m underground1 in Sudbury, Ontario, in INCO's Creighton Mine #9
1 6000 mwe
P. Wittich6
S. Gil, J. Heise, R.L. Helmer, R.J. Komar, T. Kutter, C.W. Nally, H.S. Ng, Y.I. Tserkovnyak, C.E. Waltham
University of British Columbia
J. Boger, R.L. Hahn, J.K. Rowley, M. YehBrookhaven National Laboratory
R.C. Allen, G. Bühler, H.H. Chen*University of California at Irvine
I. Blevis, F. Dalnoki-Veress, J. Farine, D.R. Grant, C.K. Hargrove, I. Levine, K. McFarlane, H. Mes,
C. Mifflin, A.J. Noble, V.M. Novikov, M. O'Neill, M. Shatkay, D. Sinclair, M. Starinsky
Carleton University
G. Milton, B. SurChalk River Laboratories
T.C. Andersen, K. Cameron, M.C. Chon, P. Jagam, J. Karn, J. Law, I.T. Lawson, R.W. Ollerhead,
J.J. Simpson, N. Tagg, J.-X. WangUniveristy of Guelph
J. Bigu, J.H.M. Cowan, E.D. Hallman, R.U. Haq, J. Hewett, J.G. Hykawy, G. Jonkmans, S. Luoma, A. Roberge, E. Saettler, M.H. Schwendener,
H. Seifert,R. Tafirout, C.J. VirtueLaurentian University
Y.D. Chan, X. Chen, K.T. Lesko, A.D. Marino, E.B. Norman, C.E. Okada, A.W.P. Poon, A. Schuelke,
A.R. Smith, R.G. StokstadLawrence Berkeley National Lab
T.J. Bowles, S.J. Brice, M.R. Dragowsky, M.M. Fowler, A. Goldschmidt, A. Hamer, A. Hime, K. Kirch,
G.G. Miller, J.B. Wilhelmy, J.M. WoutersLos Alamos National Laboratory
J.D. Anglin, M. Bercovitch, W.F. Davidson, R.S. Storey*National Research Council of Canada
J.C. Barton, S. Biller, R.A. Black, R.J. Boardman, M.G. Bowler, J. Cameron, B. Cleveland, X. Dai, G. Doucas, J. Dunmore, H. Fergani, A.P. Ferraris, K. Frame, H. Heron, N.A. Jelley, A.B. Knox, M. Lay, W. Locke, J. Lyon, S. Majerus, N. McCauley, G. McGregor, M. Moorhead, M. Omori, N.W. Tanner, R.K. Taplin, P. Thornewell,M. Thorman, P.T. Trent,
D.L. Wark, N. West, J. WilsonUniversity of Oxford
E.W. Beier, D.F. Cowen, E.D. Frank, W. Frati, W.J. Heintzelman, P.T. Keener, J.R. Klein, C.C.M. Kyba, D.S. McDonald, M.S. Neubauer, F.M. Newcomer, S.M. Oser, V.L. Rusu, R.G. Van de Water,R. Van Berg, P. Wittich
University of Pennsylvania
R. Kouzes, M.M. LowryPrinceton University
E.Bonvin, M.G. Boulay, Y. Dai, M. Chen, E.T.H. Clifford, , F.A. Duncan, E.D. Earle,H.C. Evans, G.T. Ewan, R.J. Ford, A.L. Hallin, P.J. Harvey, R. Heaton, J.D. Hepburn, C. Jillings, H.W. Lee, J.R. Leslie, H.B. Mak, A.B. MacDonald,W. McLatchie, B.A. Moffat, B.C. Robertson, T.J. Radcliffe,
P. SkensvedQueen's University
Q.R. Ahmad, M.C. Browne, T.V. Bullard, T.H. Burritt, G.A. Cox, P.J. Doe,C.A. Duba, S.R. Elliott, J.V. Germani, A.A. Hamian, R. Hazama, K.M. Heeger, M. Howe, R. MeijerDrees, J.L. Orrell,
R.G.H. Robertson,K.K. Schaffer, M.W.E. Smith, T.D. Steiger, J.F. Wilkerson
University of Washington*Deceased
SNO Collaboration
P. Wittich7
In matter:
2sec)/(1
2tan2tan m
m
eosc LL
Neutrino oscillationsNeutrino oscillations
• Recall (vacuum, two family):
L/E determines experimental sensitivity.
Typical L/E (L:m, E: MeV)Typical L/E (L:m, E: MeV)
Mixing angle
E
Lm222
e 27.1sin2sin)P(
21
22 mm
1019-1020Supernova
1010-1011Solar
102-104Atmos.
100-102Reactor
10-2 - 101Accl.
P. Wittich8
SNO reactions
e
e
NC
CC
-Good measurement of e energy spectrum-Weak directional sensitivity 1-1/3cos
-Measure total 8B flux from the sun.
-Low Statistics-Strong directional sensitivity
All types butenhanced sensitivity to e
NCNCxx npd
ESES -- eνeν x x
CCCC -eppd e
e only
Equal cross sectionfor all types
)(15.0ES
CC
e
e
Smoking Gun, model independent Significant with SuperK
P. Wittich9
SNO Run Sequence
Pure D2O– Good CC sensitivity
Added Salt in D2O– Enhanced NC sensitivity
Neutral Current Detectors– 3He proportional counters
in the D2O
Neutron Detection Method
Capture on D
Capture on Cl
Capture on 3He
Event-by-event separation of CC and NC events
n 3He p t
n 35Cl 36Cl … e (E = 8.6 MeV)
n d t … e (E = 6.3 MeV)
The Three Phases
1
2
3
P. Wittich10
NC Salt (BP98)
Signals in SNOSignals in SNOSNO MC assuming BP98 solar model (no oscillations)
Counts
in D
2O
/year/
hit
pm
t
Hit PMT’s (~Ee)
P. Wittich11
SNO: HandlesSNO: HandlesES
CCCharged current energy response leads to good sensitivity to spectral distortions.•ES: e washed out (SK)
•CC: need lots of statistics (>>1year)
•NC background to CC spectrum
Charged current energy response leads to good sensitivity to spectral distortions.•ES: e washed out (SK)
•CC: need lots of statistics (>>1year)
•NC background to CC spectrum
SNO GOAL:CC/NC ratio is a direct signature for oscillations. ES: SK, SNO
In addition:
P. Wittich12
Neutrino Candidate
P. Wittich13
SNO Results from Phase 1: Analysis outline
• Calibration• Data reduction• Final Fit
Physics results:
• CC flux (CC/ES ratio)
•More soon:
•Day/night, NC in D2O
P. Wittich14
Extracting Signals in Phase 1
Three signals, three handles
EnergyDistribution
RadialDistribution
SolarDirection
Distribution
Extended maximum likelihood fits amplitudes
P. Wittich15
SNO result: CC flux
NB: SNO CC flux < SNO ES flux (1.6 ). Also, SNO CC < SK ES (3.3 )
SNP: e SNP: e
Ratio of CC to BPB01 = 0.347± 0.029Ratio of CC to BPB01 = 0.347± 0.029
SNO measurements:
CC (8B) = 1.75 ± 0.07 ± 0.05
(stat) (sys.) (theor)
ES (8B) = 2.39 ± 0.34 (stat) (sys.)
+0.12- 0.11
+0.16- 0.14
(Units of 106/cm2/sec)
P. Wittich16
Implications: SNO Results
To Active Neutrinos To Sterile Neutrinos
sterile neutrino solutions strongly disfavored
P. Wittich17
Solar
(SuperK ES, SNO CC)
• m2 ~ 10-4 - 10-12 eV2
•sin22 - LMA large
•CCSNO/ESSK 3.3.
Neutrino oscillations: evidence roundup
Atmospheric
(SuperK)
• m2 ~ 310-3 eV2
•sin22 ~ 1
•Oscillation to s disfavored at 99%CL
Atmospheric
(SuperK)
• m2 ~ 310-3 eV2
•sin22 ~ 1
•Oscillation to s disfavored at 99%CL
LSND
m2 ~ 1 eV2
Sterile? ( )
LSND
m2 ~ 1 eV2
Sterile? ( )02 m
P. Wittich18
What’s next for ’s
• Minos - sensitive to atmospheric
• KamLand - sensitive to solar LMA
• miniBoone - address LSND
• Minos - sensitive to atmospheric
• KamLand - sensitive to solar LMA
• miniBoone - address LSND
Further off…• CP violation in MNS?
– Longer ways away…
• What about 13?
Address extra-terrestrial evidence with terrestrial experiments….
Solar neutrinos
•SNO NC/CC in D2O, day/night
•Borexino 7Be
P. Wittich19
Minos Sensitivity
Study 23 (atmospheric nu’s)
10 kT-years exposure
Null hypothesis (no osc.)
NUMI public pages
P. Wittich20
Kamland
From Kamland-US proposal.
Solar LMA in reach
• Reactor with very long baseline
• (Solar too…)
P. Wittich21
MiniBooNE Sensitivity to LSND
preliminaryIn two years, MiniBooNe can exclude the LSND region. Start taking data this year
P. Wittich22
BorexinoMeasure 7Be solar nu’s
Esp. sensitive to SMA
Data taking 5/2002
Borexino public pages
P. Wittich23
Silicon tracker
Time-of-Flight
Drift chamber
Plug calorimeter
Muon systems
Solenoid
Central calorimeter
CDF II
Substantial upgrades from Run I detector, of relevance for B physics
P. Wittich24
Oscillation in Quarks• CKM describes quark mixing• Also sensitive to ‘new physics’
What can you do at CDF (since we have B factories)?
•Access to other modes, such as Bs
•High bbar(ppbar)~ 100 b
•This comes at considerable cost…•Disadvantages:
–High backgrounds, coupled with low branching fractions, make interesting data hard to trigger on
•Need an effective B trigger.–CDF D2 low compared to B factories ( ~11% Run II estimate, rather than ~26% at BaBar)
–Better particle ID
nb7~)(
nb1~))4((0Z
S
bb
bb
nb7~)(
nb1~))4((0Z
S
bb
bb
CDF’s B program complementary
P. Wittich25
ms: motivation
By measuring ms, we can get at Vtd:
22
22
tssss
tdddd
s
d
VBf
VBf
m
m
ss s s
Information about one side of triangle.
P. Wittich26
How to measure ms
isii
iii tm
tNtN
tNtNtA
cos)()(
)()()(
unmixedmixed
unmixedmixedmixed
)cos1(e2
1),( 00 tmtBBP s
tss
Oscillation probability:
Determine the oscillation as a function of proper decay time:
P. Wittich27
How to measure ms, cont’d1. Find decay into
favorite mode
2. Determine meson type at creation
3. Measure proper decay length
4. Count oscillated vs non-oscillated as f(t)
KKD
DB
s
ss
;
;0
Txy p
mLc
Flavor tagging
P. Wittich28
Sensitivity
tpp
m plt
:lengthdecay proper ony Uncertaint
tpp
m plt
:lengthdecay proper ony Uncertaint
accurate estimate of decay length crucial
•For CDF, D2 small (~5% Run I, ~11% Run II exp.)
•Need large statistics (and/or good trigger)
Effect: ND2N
fully reconstructed modes: p negligible
P. Wittich29
• For fast oscillations:– Proper time
resolution– Dilution– Momentum
resolution• Fully
reconstructed modes
ms sensitivity: what matters?
Run I study for partially reconstructed mode:
νφl0s XB
P. Wittich30
• In Run II, CDF triggers on displaced tracks in trigger: exploit long B lifetimes.
• Ideal for enriched hadronic B samples– (cf Run I)
It works!
CDF II: SVT trigger
CDF II: SVT trigger
P. Wittich31
SVT, continued•Reconstructed with quantities available in the trigger
To do:
•SVX coverage
•L00
•SVT optimization
P. Wittich33
Flavor Tagging Determine the initial flavor of the B0
sOpposite side tags
Same side tags - TOF new to RunII
• SLT: 1.7%
•JetQ: 3.0%
•OSK: 2.4% (RunII est)
Run I
P. Wittich34
Tagging w/TOF: SSK
TOF:
•2 K/ separation for p < 1.6 GeV
•With COT dE/dx, stat separation
•K vs ? 1.0% 4.2% with TOF
P. Wittich35
Some numbers: estimated Bs yield
• Br(B0s D+
s+)= 3 x 10-3
• Br(D+s +)x Br(K+K-)=1.8%
Therefore, the total usable Bf Bftot~5.4 x 10-6.
(B0s) ~ 20 b
aBftot (B0s) ~ 5 pb-1.
Assuming full coverage, perfect reco, …, 5 Bs decays to tape per
pb-1
KKD
DB
s
ss
;
;0
P. Wittich36
Shutdown
Delivered
To tape
Run II so far
• L ~ 1.0 x 1031 sec-1 at beginning of store.• FNAL BD: 50pb-1 delivered by Summer 2002• CDF efficiency still needs work…
•Not a lot of Bs to tape yet
Jul Oct Jan
P. Wittich37
Reach for Run II: 50 pb-1
and 2 fb-1Reach for Run II: 50 pb-1
and 2 fb-1
For Run IIa (2 fb-1):
Expect ~ 10,000 Bs decays
For Summer 2002: 50 pb-1
Expect ~250 Bs on tape
Even this is a bit optimistic …
Time well spent tuning detector and analysis…
P. Wittich38
Current Status: Getting ready•B lifetime study: precursor
•Study of detector resolution (cf. Run I)
P. Wittich39
CKM MNS
Mixing Onset Goal
Approximate form
Masses ~hierarchical Flat?
Phases 1 in SM Marjorana? Dirac?
CP violation Established Unknown
In Summary: MNS vs CKM
1smallsmall
small1small
smallsmall1
CKMU
largelargelarge
largelargelarge
smalllargelarge
MNSU
Lots to do in both fields in the near future…
P. Wittich40
SNO calibrationsElectronics Calibration
q, t pedestals, discriminator walks & thresholds, TAC slopes
Optical CalibrationPulsed laser ~2ns (337, 365, 386, 420, 500 and 620 nm)Attenuation, Reflection, Scattering, PMT relative QE
Energy Calibration• 16N 6.13 MeV (also good for pointing)• p,T 19.8 MeV ’s (high E calibration point)• neutrons 6.25 MeV (NC response - bkgnd CC)• 8Li spectrum (CC also good for vertexing)
Low Energy BackgroundsEncapsulated Th and U sources
P. Wittich43
Signal Distributions
Signal Distributions
Radial Distribution Solar Direction Distribution
P. Wittich44
Error SourceEnergy scaleEnergy resolutionNon-linearityVertex shiftVertex resolutionAngular resolutionHigh Energy ’sLow energy
backgroundInstrumental
backgroundTrigger efficiencyLive timeCut acceptanceEarth orbit eccentricity17O, 18OExperimental
uncertaintyCross-sectionSolar Model
ES error (%) -3.5, +5.4
±0.3±0.4±3.3±0.4±2.2
-1.8, +0.00.0
-0.5, +0.00.0
±0.1-0.6, +0.7
±0.20.0
-5.7, +6.83.0
-16, +20
CC error (%)
-5.2, +6.1±0.5±0.5±3.1±0.7±0.5
-0.3, +0.00.0
-0.2, +0.00.0
±0.1-0.6, +0.7
±0.20.0
-6.2, +7.03.0
-16, +20
Signal Extraction Systematic Uncertainties
From varying pdfs by MC vs. calibration differences
P. Wittich45
What about other physics?•Atmospheric ’s: mixing to active flavors established by SuperK at 10.
•LSND - sterile neutrinos suggested, disfavored by solar and atmospheric data - miniBoone
•0test for Majorana masses
•Current direct mass limits
)( MeV18
)( keV 190
)( eV 2.2 33
nm
m
eHeHm ee
Recent controversial claims of evidence…
P. Wittich46 hep-ph/0201231
0
P. Wittich47
Current limits in plane
hep-ph/0201071
K from Kaons
md: B0 osc
Vub, Vcb from other B decays Babar, Belle
ms : limits only…
P. Wittich49
Current limits on ms
LEPBOSC results from CKM workshop 2/2002
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