# Presentation: 089283

## From Solar Neutrinos to B Physics: Flavor Oscillations at SNO and CDF

- Peter Wittich
- University of PA
- March 1, 2002

- From Solar Neutrinos to B Physics: Flavor Oscillations at SNO and CDF

- P. Wittich

**Notes:**
Goal of talk: bring together two disparate fields.

Describe what’s seen here: Tevatron is maybe obvious, and SNO is obvious to other half, but ...

Outline:
Tie-in the two
SNO’s CC result (cf my thesis measurement)
 Resume of current status of neutrino physics (oscillation in particular)
CDF: B physics, dm_s
Reach and prospects

## What ties these two experiments together?

|  | 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. Wittich

**Notes:**
At first glance, these two experiments are very different:

SNO’s a simple, monolithic detector (all PMT’s, no other detector components) for one main purpose: solar neutrino problem. CDF is a multi-purpose, colliding beam detector with many subsystems, many of them individually as complicated as SNO (Si, COT).

However, looking at one subset of the physics that CDF has been used to address (B physics), it’s the same underlying physics: flavor oscillations.

## Flavor Oscillations

- Wolfenstein: CKM

- PDG “standard”: MNS

- P. Wittich

**Notes:**
Suggestive parameterizations - Wolfenstein for CKM matrix, other for MNS. MNS isn’t nearly diagonal - only s13 is small. So you can’t use that parameterization for the neutrino sector.

## Solar Neutrino Problem

- Bahcall

- Bahcall

- Most plausible solution: flavor oscillations in ’s

- Solar Model

- Spectra

- Experiments

- P. Wittich

**Notes:**
Nigel: add other solar model authors.

Point to get across:
Sun only produces nu_e
All experiments detect too few nu’s (some measure nu_e, some measure nu_x, they measure different parts of the spectrum and get different results
Possible solutions:
SSM is wrong
Constrained by other measurements.
Wrong experiments 
Too many, different systematics, different media, ...
New physics!
Neutrino oscillations is just one of them. Other attempts: WIMPS to reduce the solar core temperature (affects ^8B flux directly). Can’t fit all experiments though, even if you float ^8B flux.
Neutrino oscillations is not totally crazy: see CKM

## SNO Detector

- 1 kT virgin D2O

- ~ 10,000 PMTs
- on 16.8 m support (LBL!)

- 7 kT H2O, ultrapure

- Penn Electronics

- Control
- Room

- Urylon
- liner

**2039 m underground****1**** in Sudbury, Ontario, in INCO's Creighton Mine #9**

- 1 6000 mwe

- P. Wittich

**Notes:**
Main points here: 1kT D2O, water cerenkov detector. Distinguished from other water cerenkov detectors by heavy water.

Heavy water is `virgin’ as it’s not been used as reactor fuel
Ultrapure: how pure?

## SNO Collaboration

- 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. Yeh
**Brookhaven 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. Sur
**Chalk 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. Wang
**Univeristy 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. Virtue
**Laurentian 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. Stokstad
**Lawrence 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. Wouters
**Los 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. Wilson
**University 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. Lowry
**Princeton 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. Skensved
**Queen'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

- P. Wittich

**Notes:**
~100 physicists from ~15 institutions, INCLUDING LBL COLLABORATORS!

## Neutrino oscillations

- Recall (vacuum, two family):

- L/E determines experimental sensitivity.

- Typical L/E (L:m, E: MeV)

- Mixing angle

- P. Wittich

**Notes:**
At base, neutrino oscillations is just a QM problem.  The free particle eigenstates != the weak eigenstates. Generate a particle in flavor eigenstates, and propage in mass eigenstates.

In matter: additional compilcation:
Birefringent crystal
Different forward scattering amplitude for nu_e, nu_tau,mu . Can get resonant behavior in changing L_e regardless of vacuum mixing angle.

## SNO  reactions

- Smoking Gun, model independent

- Significant with SuperK

- P. Wittich

**Notes:**
SNO has model independent way of measuring oscillation
All reaction detect Cerenkov light: e’s for CC, ES. Gamma’s for neutron capture
Both ES and NC measure all neutrinos, but ES is in some unknowable ratio
CC/ES has some sensitivity to reaction rate
CC/NC canceling systematics as all SNO (S
CC Q value 1.44 MeV

NO CC/ES is not so good, need SNO CC/SuperK ES)

## SNO Run Sequence

- _Pure D__2__O_
- Good CC sensitivity
- _Added Salt in D__2__O_
- 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***** ******** ****3****He ******** p ******** t**

***n***** ******** ****35****Cl ******** ****36****Cl ******** ******** ... ******** e********  (E************ = 8.6 MeV)**

***n***** ******** d ******** t ******** ******** ... ******** e********  (E******** = 6.3 MeV)**

- The Three Phases

**completed*****

**in progress**

- future

- 1

- 2

- 3

- P. Wittich

**Notes:**
Run sequences defined by neutron detection method.
However, other tradeoffs, too (backgrounds change, so not trivial to merge different data sets.)

## Signals in SNO

- SNO MC assuming BP98 solar model (no oscillations)

- Counts in D2O/year/hit pmt

- Hit PMT’s (~Ee)

- P. Wittich

**Notes:**
To take away from this: big background lurking low down
Real rates suppressed by ~1/3 for CC due to oscillations

## SNO: Handles

- ES

- CC

- 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. Wittich

**Notes:**
Main point of this slide is to talk about NC/CC ratio.
However, you can try to do spectral distortions. -- most significant on SMA (but data points to LMA!)

## Neutrino Candidate

- P. Wittich

**Notes:**
This is high energy event (~10 MeV)
Most have even crappier rings

## 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. Wittich

## Extracting Signals in Phase 1

- Three signals, three handles

- Energy
- Distribution

- Radial
- Distribution

- Solar
- Direction
- Distribution

- Extended maximum likelihood fits amplitudes

- P. Wittich

**Notes:**
Assumptions include no backgrounds afterwards - after data cleaning, you have an upper estimate on the amount of background, and that’s put in as a systematic error. 

## SNO result: CC flux

- SNO result: CC flux

- NB: SNO CC flux < SNO ES flux (1.6 ). Also, SNO CC < SK ES (3.3 )

-  SNP: e 

- Ratio of CC to BPB01
-       = 0.347± 0.029

- (Units of 106/cm2/sec)

- P. Wittich

## Implications: SNO Results

- To Active Neutrinos

- To Sterile Neutrinos

- sterile neutrino solutions strongly disfavored

- P. Wittich

## Neutrino oscillations: evidence roundup

- _(SuperK ES, SNO CC)_
-  m2 ~ 10-4 - 10-12 eV2
- sin22 - LMA  large
- CCSNO/ESSK 3.3.

- _Atmospheric_
- (SuperK)
-  m2 ~ 310-3 eV2
- sin22 ~ 1
- Oscillation to s disfavored at 99%CL

- P. Wittich

## What’s next for ’s

- 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. Wittich

## Minos Sensitivity

- Study 23 (atmospheric nu’s)
- 10 kT-years exposure
- Null hypothesis (no osc.)

- NUMI public pages

- P. Wittich

**Notes:**
NUMI public pages:
Plot Conditions
All “parabolic horn” beams, 10 kiloton year exposure (detector is 3.3kt fid of far detector)
    * 2% overall flux uncertainty,
    * 2% overall CC efficiency uncertainty +(2-En)*1.5% below 2 GeV
    * 2% overall NC trigger efficiency uncertainty (4 in 5 planes trigger applied)
Short description
These curves show the 90% C.L. limits that could be set by the T-Test where the quantity T is defined as the number of identified CC events divided by the total number of events. The CC selection algorithm is described in NuMI-L-481.

## Kamland

- From Kamland-US proposal.

- Solar LMA in reach

- Reactor with very long baseline
- (Solar too...)

- P. Wittich

**Notes:**
Reactors from 80 to 800 km away, with 80% btw 140-215 km. L/E

Sensitive to L/E for solar neutrinos (I think that’s due to the matter effects in the solar sector.)
L/E ~ 10^4 due to the large distance.  Disappearance experiment, and lack of knowledge of dm^_13 gives you a ~10%, according to Gonzalez-Garcia (hep-ph/0111432)

Liquid scintillator, hopes to observe solar nu’s directly.

## MiniBooNE Sensitivity to LSND

- preliminary

- In two years, MiniBooNe can exclude the LSND region. Start taking data *this year*

- P. Wittich

**Notes:**
Mini-boone, energy-dependent fit, from miniboone public pages. Two years of running to establish this signal.

Use mineral oil due to target (^12C rather than H_2O signal).  Also better for biology.

## Borexino

- Measure 7Be solar nu’s
-  Esp. sensitive to SMA
- Data taking 5/2002

- Borexino public pages

- P. Wittich

**Notes:**
From Borexino web page:
Physics: measure ^7Be line from solar nu’s

Detector:
Borexino is an unsegmented liquid detector featuring 300 tons of well shielded ultrapure scintillator viewed by 2200 photomultipliers. The detector core is a transparent spherical vessel (Nylon Sphere, 100 micron thick), 8.5 m of diameter, filled with 300 tonnes of liquid scintillator and surrounded by 1000 tonnes of a high-purity buffer liquid. The scintillator mixture is pseudocumene (PC) and PPO (1.5 g/l) a a fluor, while the buffer liquid is PC alone (with the possible addition of a light quencher, DMP).
The photomultipliers are supported by a Stainless Steel Sphere (SSS) which also separates the inner part of the detector from the external shielding, provided by 2400 tons of pure water (water buffer). An additional containment vessel (Nylon film Radon barrier) is interposed between the scintillator Nylon Sphere and the photomultipliers, to the goal of reducing Radon diffusion toward the internal part of the detector.

## CDF II

- Silicon tracker

- Time-of-Flight

- Drift chamber

- Plug calorimeter

- Muon systems

- Solenoid

- Central calorimeter

- Substantial upgrades from Run I detector, of relevance for B physics

- P. Wittich

**Notes:**
CDF is a general purpose detector at the Tevatron, a ppbar collider where sqrt(s) = 2 TeV. The physics program is large.
Not designed for B physics, but can do it.
CDF starting run II with substantial upgrades.
New central tracker
New silicon - better Z coverage, no gaps, innermost layer closer to IP (on beam pipe)
Better particle ID with TOF (k/pi sep at low momenta)

## 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

- CDF’s B program complementary

- P. Wittich

## ms: motivation

- By measuring ms, we can get at Vtd:

- s

- s

- s

- s

- Information about one side of triangle.

- P. Wittich

**Notes:**
Main motivation: CKM matrix elements to see if we can break the SM (or see if CKM is correct.)

V_ts is the same as V_cb (which is well measured). Lots of errors cancel. You get information about the one side.

## How to measure ms

- Oscillation probability:

- Determine the oscillation as a function of proper decay time:

- P. Wittich

**Notes:**
Describe asymmetry measurement. What do you need: significance of result. Important is mainly knowledge of IP, 2ndary vertex. Then, the question of tagging: it is said that it doesn’t matter if you see the oscillations, but it does matter if you need to set a limit. Hmmm. Not sure I understand that.

## How to measure ms, cont’d

- Find decay into favorite mode
- Determine meson type at creation
- Measure proper decay length
- Count oscillated vs non-oscillated as *f(t)*

- Flavor tagging

- P. Wittich

## Sensitivity

- 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:
-    ND2N

- fully reconstructed modes: p  negligible

- P. Wittich

## For fast oscillations:
Proper time resolution
Dilution
Momentum resolution
Fully reconstructed modes

- Proper time resolution
- Dilution
- Momentum resolution
- Fully reconstructed modes

- ms sensitivity: what matters?

- Run I study for partially reconstructed mode:

- P. Wittich

## In Run II, CDF triggers on displaced tracks in trigger: exploit long B lifetimes.
Ideal for enriched hadronic B samples
(cf Run I)

- Ideal for enriched hadronic B samples
- (cf Run I)

**It works!**

- CDF II: SVT trigger

- P. Wittich

**Notes:**
    * SVT tracks matched with COT tracks at L3 ("hybrid tracks"):
          * |phi(SVT) - phi(COT)| < 0.01
          * |c(SVT) - c(COT)| < 0.0001 (curvature)
    * each track:
          * pT > 2 GeV/c
          * SVT fit chi2 < 15
          * 100 um < |d(SVT)| < 1 mm
    * opposite charge
    * pT1 + pT2 > 5.5 GeV/c
    * |delta z0| < 5 cm
    * |delta phi| < 135 degrees
    * 0 < Lxy < 3 cm

## SVT, continued

- Reconstructed with quantities available in the trigger

- To do:
- SVX coverage
- L00
- SVT optimization

- P. Wittich

**Notes:**
Better SVT coverage, still some dead ladders(never fixed), not reading out L00

Without L00, the time resolution goes from 45 fs to 60 fs (and currently maybe 65 fs)

## SVX performance

- P. Wittich

**Notes:**
 *       * Production version 4.3.0, OI silicon tracking
          * Runs 127400-128449, 13644, and 137467-139177 (1.05 pb-1)
          * each track:
                * number of r-phi hits in SVX >= 3
                * number of axial COT hits >= 20
                * number of stereo COT hits >= 20
                * pT > 1.5 GeV/c
                * |d0| < 1 mm
          * phi candidate:
                * opposite-charge track pair
                * |delta z0| < 10 cm
                * 1.01 GeV/c2 < m(KK) < 1.03 GeV/c2
          * pion candidate:
                * |delta z0| < 10 cm to average z0 of phi daughter tracks
          * 3-prong vertex:
                * at least one track has |d0| > 100 ?m
                * VertexFit chi2 in r-phi < 10
                * Lxy > 0
                * |cos(helicity angle)| > 0.4
          * duplicate candidates removed based on vertex chi2
          * note: it is likely that the relatively long D+ lifetime is contributing to the large D+/Ds ratio in the phi-pi mass spectrum in the displaced-track trigger sample

## Flavor Tagging

-  Determine the initial flavor of the B0s

- Opposite side tags

- Same side tags - TOF new to RunII

-  SLT: 1.7%
- JetQ: 3.0%
- OSK: 2.4% (RunII est)

- Run I

- P. Wittich

**Notes:**
Talk about different tags:
OST:
Jet charge
Soft lepton tag
Opposite side Kaon tags
Same side tags
Same side kaon tags

## 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. Wittich

**Notes:**
MJONES: time resolution of 100 ps for TOF
2sigma K/Pi sep for p<1.6 GeV
Well suited for B physics

216 Bars
140CM readius
Eta < .9
Length: 2.8m
Bicron Scintillator
19 stage mesh tube (Hamamatsu R7761)
In between COT and solenoid

Tagging algorithm: Look for track close to B_s candidate 
See if it’s a K or a pi

Reconstruction: thit = d/(beta c) - t0. Due to long bunches in the tevatron, the t0 distribution has a 1.2 ns width. This overwhelms single channel resolution. So you have to measure t0 on an event-by-event basis.

## Some numbers: estimated Bs yield

*Br(B**0**s**** 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

- P. Wittich

**Notes:**
Where does ea come from?

This is a bit of a back-of-the envelope estimate. 

The total x-section for B_s comes from the bbar production cross-section into 4pi. The fraction of B_d of that has been measured, as well as the relative fractions of B_d vs B_s. Then you get the estimate for the B_s fraction from this. Again, *this is into 4pi.*.

E_a is supposed to take everything into account - the trigger, fiducial, the tagging, etc etc etc....

## 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. Wittich

**Notes:**
The estimate for Run II a is 2fb^-1, six month shutdown and then Run II b with a total of 15 fb^-1. The luminosity profile has to go up soon for us to start reaching that...

Run II a is ~3 years, with the estimated 6 month shut-down in 2004. Run II b starts in 2005. Major changes for CDF: new Si detector. Run II a peak luminosity wth 132 ns beam spacing is 2E32. With 396, it’s ~1E32.   Run II b: 5E32, 132 ns beam spacing.

Delivered lumi/week:
17: II a, 396
42: II a, 132
105: II b

“The typical luminosity at the beginning of the store has translated to integrated efficiency with a 33% duty factor”

No estimate on when to go to 132 ns bunch spacing.  FY03 is from Matthew (some BD web page.)

## Reach 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. Wittich

**Notes:**
This estimate is optimistic as there is another large factor for all the other tracks being in your fiducial volume to allow you to do reconstruction, tagging, and the like. The number is something like 25% from a Bgenerator study.

On the other hand, the recent ALEPH paper has something like 80 candidate B_s events in their fully reconstructed B_s decay channels and they can and do publish it....

## Current Status: Getting ready

- B lifetime study: precursor
- Study of detector resolution (cf. Run I)

- P. Wittich

## In Summary: MNS vs CKM

|  | CKM | MNS |
| --- | --- | --- |
| Mixing | Onset | Goal |
| Approximate form |  |  |
| Masses | ~hierarchical  | Flat? |
| Phases | 1 in SM  | Marjorana? Dirac? |
| CP violation | Established | Unknown |

- Lots to do in both fields in the near future...

- P. Wittich

## SNO calibrations

- Electronics Calibration
- q, t pedestals, discriminator walks & thresholds, TAC slopes
- Optical Calibration
- Pulsed 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 Backgrounds
- Encapsulated Th and U sources

- P. Wittich

## SNO:Data Reduction

- The problem: S/N ~ 1/106.
- Few handles: shape, time structure of Cerenkov light
- Instrumental *can* mimic
- Radioactivity *does* mimic
- Other physics
- NC to CC and vice versa
- Muons, even at 2km!

- P. Wittich

## Instrumental Backgrounds

- P. Wittich

## Signal Distributions

-       Radial Distribution

- Solar Direction Distribution

- P. Wittich

**Notes:**
Data fits to results.  I think this is from Mark’s thesis, not from published results.

**Error Source**
- Energy scale
- Energy resolution
- Non-linearity
- Vertex shift
- Vertex resolution
- Angular resolution
- High Energy ’s
- Low energy background
- Instrumental background
- Trigger efficiency
- Live time
- Cut acceptance
- Earth orbit eccentricity
- 17O, 18O
- Experimental uncertainty
- Cross-section
- Solar Model

**       ****ES error (%)**
-       -3.5, +5.4
- ±0.3
- ±0.4
- ±3.3
- ±0.4
- ±2.2
- -1.8, +0.0
- 0.0
- -0.5, +0.0
- 0.0
- ±0.1
- -0.6, +0.7
- ±0.2
- 0.0
- -5.7, +6.8
- 3.0
- -16, +20

**CC error (%)**
- -5.2, +6.1
- ±0.5
- ±0.5
- ±3.1
- ±0.7
- ±0.5
- -0.3, +0.0
- 0.0
- -0.2, +0.0
- 0.0
- ±0.1
- -0.6, +0.7
- ±0.2
- 0.0
- -6.2, +7.0
- 3.0
- -16, +20

- Signal Extraction

-  Systematic Uncertainties

- From varying pdfs by MC vs. calibration differences

- P. Wittich

## 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
- 0test for Majorana masses

- Recent controversial claims of evidence...

- P. Wittich

## 0

- 0

- P. Wittich

**Notes:**
Implications:

Rules out models that have small dirac masses. Some recent models have large extra dimensions where gravity is strong, which “naturally” allows for small Yukawa couplings to the neutrino and hence a naturally small dirac neutrino mass. According to K-K, this is “ruled out” by the above evidence.  This rules out some theories of large extra dimensions.

You get at the mass by:
For helicity considerations, the “wrong” helicity state has some probability proportional to m_nu/E_nu, and the rate should be proportional to m_nu^2/m_e^2

## 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. Wittich

**Notes:**
Need to look at this in detail

## Current limits on ms

- Current limits on ms

- As published by the B Oscillation Working Group.

- P. Wittich

**Notes:**
Got this from the B oscillation workshop, with hint of signal at 17 ps^-1

## Current limits on ms

- LEPBOSC results from CKM workshop 2/2002

- P. Wittich

**Notes:**
95 CL excluded < 14.9 ps^-1
World sensitivity 19.3 ps^-1