reactor & accelerator thanks to bob mckeown for many of the slides

Reactor & Accelerator

Thanks to Bob McKeown for many of the slides

June 2005 Steve Elliott, NPSS 2005 2

Outline

• Reactor NeutrinosThe neutrinosPast experimentsWhat we know and what we want to learn

• Accelerator NeutrinosThe neutrinosPast experimentsWhat we know and what we want to learn

June 2005 Steve Elliott, NPSS 2005 3

Distance (m)

P(ee)

€

Pee ≈1− cos4 θ13 1− sin2θ12 sin2 Δm122L

4Eν

⎛

⎝ ⎜

⎞

⎠ ⎟

⎡

⎣ ⎢

⎤

⎦ ⎥

Dominant 12 Oscillation

€

Pee ≈1− sin2 2θ13 sin2 Δm312L

4Eν+

Δm212L

4Eν

⎛

⎝ ⎜

⎞

⎠ ⎟cos4 θ13 sin2 2θ12

Subdominant 13 Oscillation

e Disappearance

June 2005 Steve Elliott, NPSS 2005 4

13

90, 95, 99% CL

hep-

ph/0

3091

30

m232 from SK

atmospheric

Chooz

Solar

122

134

122

134

NCCC sinsinsincos/ ≈+≈ΦΦ

June 2005 Steve Elliott, NPSS 2005 5

Neutrino Oscillation Studies with Nuclear Reactors

• e from n-rich fission products

• detection via inverse beta decay (e+pe++n)

• Measure flux and energy spectrum

• Improve detectors, reduce background

• Variety of distances L= 10m-250km

June 2005 Steve Elliott, NPSS 2005 6

Detection Signal

Coincidence signal: detect• Prompt: e+ annihilation EEprompt+En+0.8 MeV• Delayed: n capture 180 s capture time

p+e

511keV

511keV 2.2 MeV

d

n

June 2005 Steve Elliott, NPSS 2005 7

June 2005 Steve Elliott, NPSS 2005 8

KamLAND usesthe entire Japanese

nuclear powerindustry as a

long baseline source

Kashiwazaki

Takahama

Ohi

June 2005 Steve Elliott, NPSS 2005 9

June 2005 Steve Elliott, NPSS 2005 10

Solar : m2 = 5.5x10-5 eV2

sin2 2 = 0.833

G.Fogli et al., PR D66, 010001-406,(2002)

Ratio of Measured and Expected e Flux

from Reactor Neutrino Experiments

June 2005 Steve Elliott, NPSS 2005 11

Measurement of Energy Spectrum

June 2005 Steve Elliott, NPSS 2005 12

KamLAND best fit : m2 = 7.9 x 10-5 eV2

tan2 = 0.45

KamLAND fixes massSolar fixes angle

June 2005 Steve Elliott, NPSS 2005 13

New Reactor Proposals

Braidwood, Il

Daya Bay, China

Chooz, France

• ~1.5 km baseline• Deeper/bigger• Near/Far

June 2005 Steve Elliott, NPSS 2005 14

Detector Design Studies

horizontal cylinder

horizontal cylinder

spherical

June 2005 Steve Elliott, NPSS 2005 15

Oscillation Formulae for Long-Baseline Neutrinos

For anti-neutrinos, the Jcp terms change sign.

June 2005 Steve Elliott, NPSS 2005 16

Long Baseline Physics Goals

• Definitive observation of oscillatory behavior in disappearance mode and precise determination of m2

23 and 23.

• Detection of oscillation e in appearance mode and measurement of 13.

• Observe matter effects, hence sign of m223.

• Measure cp

June 2005 Steve Elliott, NPSS 2005 17

CP violation and matter effects

he

p-p

h/0

30

62

21

June 2005 Steve Elliott, NPSS 2005 18

T2K

Phase I0.75 MW +SKPhase II4 MW + HyperK

June 2005 Steve Elliott, NPSS 2005 19

HyperK

June 2005 Steve Elliott, NPSS 2005 20

NOAUse the NUMI beam line from FermiLab.Far detector uses alternate vertical planes of active scintillator with passive wood absorber.

June 2005 Steve Elliott, NPSS 2005 21

Off-Axis Beam• For pions decaying in

flight, most neutrinos are forward directed

• Neutrino energy is proportional to E

• Neutrino energy flattens with angle, however. Allowing one to “choose” an energy by choosing the angle.

June 2005 Steve Elliott, NPSS 2005 22

Far Detector810 km from target10-14 km off axis

June 2005 Steve Elliott, NPSS 2005 23

LONG baseline 2500-3000 km

June 2005 Steve Elliott, NPSS 2005 24

The LSND Puzzle and MiniBOONE

30 meters

e detector

Neutrinose, , and

Protonbeam

Pions

Copper beam stop

Muons and electrons

Watertarget

June 2005 Steve Elliott, NPSS 2005 25

The Evidence for Neutrino Oscillations

June 2005 Steve Elliott, NPSS 2005 26

Requires a 3rd m2

June 2005 Steve Elliott, NPSS 2005 27

June 2005 Steve Elliott, NPSS 2005 28

June 2005 Steve Elliott, NPSS 2005 29

Measurement of Oscillation Parameters

June 2005 Steve Elliott, NPSS 2005 30

Typical Muon-Neutrino Event

June 2005 Steve Elliott, NPSS 2005 31

Typical Michel Electron Event

June 2005 Steve Elliott, NPSS 2005 32

Resources

• Bob Mckeown APS April 2005 (Tampa)

• APS neutrino study on reactors and long baseline experiments.

• BNL, T2K and NOA Letters of Intent

• Bill Louis Talks