# Presentation: 091269

## The NOvA Experiment
(NuMI Off-Axis ve Appearance)

Robert Bernstein
Fermilab

NO-VE 2006
Neutrino Oscillations in Venice
7 February 2006
(For the Collaboration)

- (NuMI Off-Axis *v**e* Appearance)
- Robert Bernstein
- Fermilab
- NO-VE 2006
- Neutrino Oscillations in Venice
- 7 February 2006
- (For the Collaboration)

## Physics Goals:
A developing, staged program:
 (e Appearance) 
Sign of m2
CP-Violation
The NOvA detector:
Size, structure, resolution
Comparison to MINOS
Near detector
Simulations and Backgrounds:
What is done and what is underway
Status, Cost & Schedule

- A developing, staged program:
-  (e Appearance)
- Sign of m2
- CP-Violation
- The NO*v*A detector:
- Size, structure, resolution
- Comparison to MINOS
- Near detector
- Simulations and Backgrounds:
- What is done and what is underway
- Status, Cost & Schedule

- Outline for Talk

- DoE Review June 26, 2000

## Current Ideas & Goals

- Phase 1 (Extend νμ → νe reach by order of magnitude; explore mass hierarchy & CPV)
- NOvA
- T2K (Kajita)
- Reactors: 13 (Laserre)
- Phase 2 (Extend reach for mass hierarchy & CPV)
- NOvA + PD (Geer)
- HK + PD
- Brookhaven VLBL proposal
- CERN PD + Mton H2O detector
- Phase 3 (Significantly extend reach)
- Neutrino factory
- Beta beam

- DoE Review June 26, 2000

## NuMI Off-Axis

- 15 mrad off axis & 810 km from the source
- Yields a narrow band beam on oscillation maximum
- More flux & reduced backgrounds from the HE tails

- DoE Review June 26, 2000

## NuMI Beam

- Move Horn toward/away from target:

- DoE Review June 26, 2000

## Rates and Spectra

- Spectra for NuMI Medium Energy Beam:

- Source of ’s to be cut

- DoE Review June 26, 2000

## P(νμ → νe) in Vacuum

- P(e) = P1 + P2 + P3 + P4
- note terms with m13 and  mix, hence matter-CP ambiguity

- Atmospheric

- Atmospheric-
- solar interference

- Solar

- DoE Review June 26, 2000

**Notes:**
In units so that 1.27 = 1

## P(νμ → νe) (in Matter)

- In matter at oscillation maximum, P1 will be approximately multiplied by (1 ± 2*E*/*E**R*) and P3 and P4 will be approximately multiplied by (1 ± *E*/*E**R*), where the top sign is for neutrinos with normal mass hierarchy and antineutrinos with inverted mass hierarchy
- 	About ±30% effect for NuMI/NoA
- 	About ±11% effect for T2K
- The effect is reduced for energies above the oscillation maximum & increased for energies below

- DoE Review June 26, 2000

**Notes:**
A few comments about the size of the efffect before I show plots

## Ambiguity between Mass Ordering and CP Phase

- Need
- Ambiguity depending
- 	  on sign of m2, CP
- Statistical Errors
- More detail later
- Combining Nova and T2K also useful!

- DoE Review June 26, 2000

**Notes:**
Size of errors .002,.004 gives spread on this graph.  

## “Fraction of ” 

- Fraction of :
- Above or below significance
- cutoff?

- DoE Review June 26, 2000

**Notes:**
We show many plots that refer to “fraction of delta”, here’s what it is.

## 3  Sensitivity to 

- Fraction of δ covered

- Blue “Reactor” is APS;
- Dashed is Braidwood

- DoE Review June 26, 2000

## Sensitivity vs Time

**

- .008 at 2

- .008 at 3

- DoE Review June 26, 2000

## Importance of the Mass Ordering

- Window on very high energy scales
- Grand unified theories (mostly) favor the normal mass ordering but other approaches favor the inverted ordering
- The next generation of neutrinoless double beta decay experiment care about the mass ordering
- If inverted ordering, can decide if the neutrino is its own antiparticle
- If normal ordering, a negative result is inconclusive
- For CPV measurement we need to resolve the mass ordering
- Matter effects contributes an apparent CP violation that must be corrected

- DoE Review June 26, 2000

**Notes:**
Now we move on.  If we can find a non-zero theta_13, why do we want to measure the mass ordering?

## Role of NOA in Resolvingthe Mass Ordering

- The mass ordering can be resolved only by matter effects in the earth over long baselines
- NOA is the only proposed experiment with a sufficiently long baseline to resolve the mass ordering
- The siting of NOA is optimized for this measurement
- NOA is the first step in a step-by-step program that can resolve the mass ordering in the region accessible to conventional neutrino beams

- DoE Review June 26, 2000

## 95% CL Resolution of the Mass Ordering

- Fraction of δ covered

- May not  be most recent for T2K

- DoE Review June 26, 2000

## 3  Determination of CP Violation

- Fraction of δ covered

- Must have measurement errors < 30o  (3=90o)
- Some values of  (e.g. =0) not resolvable

- DoE Review June 26, 2000

## Measurement of m322 and sin2(223)

**5-year ******** run **

**5-year ******** run**
**with Proton Driver **

- MINOS
-  5-yrs

- DoE Review June 26, 2000

**Notes:**
And of course we get excellent meausurements of the MINOS parameters.  This is something like a factor of twenty better, and the most interesting thing is whether the m ixing is maximal, and if not how non-maximal it is.  So this is not just an engineering measurement!

## Sensitivity to Off-Axis Distance

- 3 standard deviation discovery limit of NOA for   e oscillations as a function of sin2(2θ13) and the off-axis distance.
- 95% confidence level for NOA to resolve the mass hierarchy as a function of sin2(2θ13) and the off-axis distance.

- (new info from Parke?)

- red normal, blue inverted

- DoE Review June 26, 2000

## Far Detector Site

- Ash River
- Baseline site
- Can fly into International Falls (less than an hour drive to site)
- Resort area
- Kjostad Lake
- Orr-Buyck Rd
- Good backup site
- Mine Centre
- Must cross the US-Canada border (in a paper mill site) to get from airport to site
- Range of angles available at all sites

**850 km**

**810 km**

**775 km**

- DoE Review June 26, 2000

## NOvA Far Detector

- Revised Proposal (April 05)
- “Totally Active” scintillator detector (75%)
- 30 kT
- 24 kT liquid scintillator
- 6 kT of cells
- Liquid scintillator cells
- 3.9 cm x 6 cm x 15.7m
- 0.15 X0 sampling
- 1984 planes of cells
- Cell walls
- Extruded rigid PVC
- 3 mm outer; 2 mm inner horizontal; vertical 4.5 mm outside
- Readout
- U-shaped 0.8 mm WLS fiber : 27,000 km!
- APDs (80% QE)

- Horizontal/vertical cells
- different for structural strength

*One Plane: 15K kg*

- DoE Review June 26, 2000

**Notes:**
60% around Earth!

## Just how big is That? 

**15.7 m**

**132 m**

**15.7 m**

**NO********A**

- DoE Review June 26, 2000

**Notes:**
Male Blue Whales

## Far Detector Assembly

- Detector has 64 (31-plane) blocks
- Can fill with scintillator and run during construction
- Half-Size planes built & tested at Argonne

**31-plane**
**block**

**1-cm expan-**
**sion gap**

**31-plane**
**block**

- DoE Review June 26, 2000

## Half Block Prototype Being Built

- DoE Review June 26, 2000

## Number of Photoelectrons

- Transverse Cell Dimensions the same
- Length of cell shorter but 33.5 meter fiber identical
- Read out to APD
- #PE stable over 2 months
*Enough light!*

- DoE Review June 26, 2000

## NOvA vs. MINOS for 

- Other than the off-axis beam...
- Mass increased by a factor of 6
- Improved energy resolution and *e/**π*0 discrimination
- “Totally active scintillator detector” (TASD) instead of sampling calorimeter
- Increase longitudinal sampling by a factor of 10(1.5 X0 to 0.15 X0)
- All while reducing the cost/kiloton by a factor of 3 with respect to MINOS Far Detector
- No magnetic field in NO*v*A

- DoE Review June 26, 2000

## Sample MC Event1.65 GeV νeN  epπ0

- DoE Review June 26, 2000

**Notes:**
Backwards going pi^o, see conversion

## Electron ID & Energy Resolution

**Electron resolution**

- Also use RMS of pulse height per plane, gaps & energy cuts

**Electrons**

**Muons**

- DoE Review June 26, 2000

## Reconstruction

- Two Algorithms:using a maximum likelihood analysis with the following variables
- a) Total measured energy
- b) Fraction of total energy carried by the electron
- c) Mean pulse height near the origin of the electron
- d) Pulse height per plane for the electron
- e) Number of hits per plane for the electron
- f) Energy upstream of the vertex
- g)Curvature of the electron
- h) Missing transverse momentum
- i) Fraction of total electron energy contained in the first half of the electron track
- j) rms deviation of electron hits from the fitted track
- k) number of tracks identified as hadrons in the event

| Cell width | Cell Depth | Relative FOM | Electron
Energy |
| --- | --- | --- | --- |
| 3.8 | 4.5 | 1.0 | 10.0% |
| 3.8 | 6.0 | 1.02 | 10.7% |
| 5.4 | 4.5 | 0.9 | 9.9% |

- FOM = Signal/Sqrt(Bkg)

- Efficiency Typically 25-40%:
- Algorithms under development

- DoE Review June 26, 2000

## Tradeoffs

- Primary problem is tradeoff between acceptance and background rejection:
- E.g.
- Look for “gap” from photons at beginning, followed by shower
- Tradeoff of acceptance vs. shower fluctuations vs. background rate and ability to accurately model
- Beam-Related backgrounds are measurable and small
- Lots to do, progress being made

- DoE Review June 26, 2000

## Signal and Backgrounds

- Statistical Power: why this is hard and we need protons

- For sin2 213 = 0.1:
- 	:   S=142.1,  B=19.5
- 	:   S=  71.8,  B=12.1

- 5 yrs at 6.5E20 pot/yr,
-  efficiencies included

- 0.01		0.05              0.1

- 0.01		0.05              0.1

- DoE Review June 26, 2000

## Sensitivity to Reconstruction Cuts

- Vary cut on likelihood function
- What Happens to Signal/Sqrt(Bkg) = FOM
- What happens to rates?
*Nothing drastic*
*Very much under development, but we’re thinking about this and the numbers are reasonable*

- DoE Review June 26, 2000

## Far Detector Building Design with Overburden

- Overburden:Minimum thickness possible
- Under study with CORSIKA/GEANT

- DoE Review June 26, 2000

## Determination of Overburden

- Incident Rate
- Probability
- Convolution

- Need 2 m overburden to eliminate

- -flux is source of bkg:
- 	needs to come in at angle 		to look like signal

- DoE Review June 26, 2000

## Near Detector:Modular & Mobile

- M Test

- MINOS Surface Building

- NuMI Access Tunnel

*Calibrate in Test Beam*

*Response to*
***** **and ****e*

*Measure Beam*
*Properties*

- DoE Review June 26, 2000

## Near Detector

- 21.1 mTons fiducial
- 212 total
- 3.2 events/pulse

- DoE Review June 26, 2000

## Surface Measurement

**6.5 x 10****20**** pot in 75 mrad off-axis beam**

- Far Data Spectrum peaked at 2 GeV

- K peaks

- DoE Review June 26, 2000

## Cost

|  | Contingency | Total Cost M$ |
| --- | --- | --- |
| Far Detector |  |  |
|    Active detector | 30% |   80 |
|    Electronics and DAQ | 55% |   13 |
|    Shipping | 21% |     7 |
|    Installation  | 43% |   14 |
| Near Detector | 44% |     3 |
| Building and outfitting | 58% |   29 |
| Project management | 25% |     5 |
| Additional contingency |  |   14 |
| Total | 50% | 165 |

- Sensitive to price of crude oil!
- We have understanding of how price depends on petroleum price: can make sensible estimates

- DoE Review June 26, 2000

## Sensitivity to Petroleum Price

- PVC resin increases ~ $0.03/lb. for every $10/barrel increase in the cost of crude oil.

- Mineral oil increases ~$0.03/gal for every $1.00 increase in the cost of crude.

- PVC Price

- Mineral Oil Price

- Crude Oil Price

- Crude Oil Price

- DoE Review June 26, 2000

**Notes:**
PVC price and mineral oil price track crude, so we have some sense of our cost risk

## Proton Intensity

- NOA will run after the Tevatron terminates operation.  Thus, parts of the accelerator complex now devoted to antiproton production and storage will be available for the neutrino program.
- Assumption of our proposal:
- 0.7 MW, of which we assumed 0.625 MW for the NOA program.  (for no proton driver)
- Fermilab strategy:
- If ILC looks affordable, move to host the ILC and do “cheap” upgrades to the proton intensity.
- If ILC will be delayed, move toward a Proton Driver
- (i.e., a new Booster).
- We assume that the Proton Driver will allow 2.4 MW.

- DoE Review June 26, 2000

## Schedule

- Cannot start in FY2007 due to regulations on Congressional line items.
- Aiming for a FY2008 project start.
- Start of data taking October 2010
- Completion of the Far Detector July 2011

- 3 Feb 06:        President’s Budget:  White House to Congress
- 	High Energy Physics Program ($775.1 million)
- 	This is a $58.4 million increase over FY 2006.
***Project engineering and design funding of $10.3 million is requested for the ***
***	******new Electron Neutrino Appearance project.***

- !!!!

- DoE Review June 26, 2000

## From Oddone to EPP2010

- DoE Review June 26, 2000

**Notes:**
So we’re consistent...

## Conclusions

- The Fermilab/NuMI/NOA program provides a flexible, step-by-step approach:

- Gateway to Paradise:
- sin2 213

- Ghiberti’s Gates of Paradise in Firenze

- Mass
- Hierarchy
**(leaving, not coming in!)**

- m223, 23

- CP 

- DoE Review June 26, 2000