the Long Baseline Neutrino Experiment - Particle Physics at CIEMAT

wwwae.ciemat.es

the Long Baseline Neutrino Experiment - Particle Physics at CIEMAT

From Chicago to

Deadwood in 4

Milliseconds:

the Long Baseline

Neutrino Experiment

R.Svoboda, CIEMAT Madrid, April

2010


Why Study Neutrinos

• Only six known stable particles: ν 1 , ν 2 , ν 3 , p,

e, and γ. Neutrinos are half the known

stable particles in the universe.

• Estimates give ~300 ν’s cm -3 , roughly the

same density as CMB photons. Nucleons

and electrons are ~10 -7 per cm 3 . Neutrinos

are a major component of the universe.

Neutrinos allow for the study of particle

physics without the complications of the

strong and electromagnetic

interactions…


• 1956: Reines and

Cowan detect

neutrinos coming

from the core of a

nuclear reactor

• 1958: Neutrinos are

Left-Handed!

• 1962: multiple types

• Nothing more until

neutrino oscillations

confirmed in 1990’s!

4/21/2010 R.Svoboda 4


Like Gaul, Neutrinos divided into

three types

…but the three types are

not flavor eigenstates

listed in the Particle Data

Book

4/21/2010 R.Svoboda 5


Neutrino Flavor

Oscillations

⎛ ν


⎜ ν


⎝ ν

e

µ

τ






⎛ U


= ⎜ U


⎝ U

e1

µ1

τ1

U

U

U

e2

µ2

τ2

U

U

U

e3

µ3

τ3

⎞⎛

ν

⎟⎜

⎟⎜

ν

⎟⎜

⎠⎝

ν

1

2

3






s ij = sinθ ij c ij = cosθ ij

solar and

atmospheric

and accelerator

reactor and

accelerator

reactor

4/21/2010 R.Svoboda 6


Neutrinos and the Standard

Model

Massive neutrinos have several implications

beyond just lepton flavor oscillations:

- A possible non-zero magnetic moment

- Heavier neutrinos could decay into lighter

ones

- They will have an effect on the CMB

spectrum

- CP violation in early universe

- Hint of unification scale below GUTs

- One should note: Dark Matter, Dark

Energy, Neutrino Flavor violation all came


We don’t know the mass ordering or

absolute mass scale

New information will be coming soon

from several sources

4/21/2010 R.Svoboda 8


The Absolute Neutrino Mass

WMAP-5

• Limits on total

neutrino mass from

cosmology are getting

better (


Dirac or Majorana

• Do neutrinos have a mass term of the same

form as the charged leptons E.g. a Dirac

fermion.

• If so, why is the mass so small

Neutrinos could have a Majorana mass,

generated terms like ψ T C -1 ψ instead of the

usual ψψ Dirac form. This would be different

than other particles. Why

• In this case, neutrinos are their own

antiparticle. Even if Supersymmetry is found

at the LHC, neutrinos will remain a Funky


The “seesaw” mechanism

(there are many variations!)

LH Light neutrinos may have heavy RH

partners that may mix via couplings that

link LH and RH

The mass of the light neutrino goes roughly

as:

m ν ∼ m 2 /M

Where m is the mass associated with our

low energy EW scale (~246 GeV) and M is

the mass of the heavy RH partner.

Oscillation measurements imply M~10 15


Leptogenesis

• Simply put, if there does exist a RH heavy

partner for the LH neutrinos, and if such a

partner violates CP in its decay, it could

influence the baryon/anti-baryon symmetry

of the universe

• CP violation in the light neutrinos does not

prove that neutrinos have a heavy CPviolating

partner, but it is strong

circumstantial evidence

• Knowing the absolute neutrino mass and

structure would also help!


A New Physics

• Explain the symmetry of the mixing

matrices

• Explain the smallness of the neutrino

mass scale relative to u,d quarks and

electrons. Note: plausibility of seesaw

mechanism does not make it true. If it is

true, why is RH neutrino mass scale not

the GUT scale

• Understand the role of neutrinos in the

Big Bang. Neutrino mass and interactions

are closely linked to the origins of our

universe and its evolution to the current


We need to:

• Measure θ 13 as soon as possible.

• Push ahead with 0ν2β decay experiments.

• Improve CMB measurements on absolute

neutrino mass.

• Investigate neutrinos on cosmological scale

via better BAO measurments

• Design a next generation long baseline

experiment with a high-intensity neutrino

beam


Long Baseline Neutrino Experiment

(Science Collaboration)

• ~200 people

• Science Goals: We want a broad

physics program!

Neutrino Mass Hierarchy & CP violation

• Supernovae

• Relic Supernovae

• Proton Decay

• neutrino physics


Long Baseline Neutrino Science

• Alabama: J.Goon, I.Stancu

• Argonne: Z.Djurcic, M.Goodman, J.Paley, M.Wetstein

• Boston Univ: E.Kearns, J.Raaf, J.Stone

• BNL: M.Bishai, H.Chen, M.Diwan, R.Hahn, D.Jaffe,

J.S.Kettell, F.Lanni, W.Marciano, N.Samios,

J.Sondericker, C.Thorn, B.Viren, M.Yeh, B.Yu

• Univ of California, Davis: T.Classen, J.Felde, P.Gupta,

M.Tripathi, R.Svoboda

• Univ of California, Irvine: W.R.Kropp, M.Smy, H.Sobel

• Univ. of California, Los Angeles: K.Arisaka, D.Cline,

K.Lee, F.Sergiampietri, H.Wang

• Caltech: R.McKeown

• Catania and INFN: V.Bellini, R.Potenza

• Univ. of Chicago: E.Blucher

• Colorado State Univ: B.Berger, W.Toki, R.Wilson

• Univ of Colorado: A.Marino, M.Tzanov, E.Zimmerman

• Columbia: L.Camillieri, C.Y.Chi, M.Shaevitz, W.Sippach,

W.Willis

• Dakota State: B.Szcerbinska

• Drexel Univ.: C.Lane, J.Maricic,R.Millncic, K.Zbiri

• Duke Univ.: K.Scholberg, C.Walter

• FNAL: B.Baller, S.Childress, A.Hahn, J.Hylen, T.Junk,

J.Morfin, V.Papadimitriou, C.Polly, S.Pordes, G.Rameika,

B.Rebel, J.Strait, G.Zeller, P.Shanahan, R.Zwaska

• Univ of Hawaii: S.Dye, J.Kumar, J.Learned, S.Matsuno,

S.Pakvasa, G.Varner

• Indian University Consortium: V.Singh, B.C.Choudary,

S.K.Mandai, B.Bhuyan, V.Bhatnagar, A.Kumar, S.Sahijpal

• Indiana Univ.: C.Bower, M.D.Messier, J.Musser,

R.Tayloe, J.Urheim

• IPMU Tokyo University: M.Vagins

Collaboration

• Iowa State: M.Sanchez

• Kansas State Univ.: T.Bolton, G.Horton-Smith

• LBL: R.W.Kadel, B.Fujikawa

• LLNL: A.Bernstein, R.Bionta, S.Dazeley, S.Ouedraogo

• LANL: S.Elliott, G.Garvey, T.Haines, W.Louis, C.Mauger,

G.Mills, Z.Pavlovic, G.Sinnis, H.White

• Louisiana State University: N.Buchanan, T.Kutter,

W.Metcalf, J.Nowak

• Univ. of Maryland: E.Blaufuss, G.Sullivan

• Michigan State Univ.: C.Bromberg, D.Edmunds

• Univ. of Minnesota, Crookston: D.Demuth

• Univ. of Minnesota, Duluth: A.Habig

• Univ. of Minnesota: M.Marshak, W.Miller

• MIT: P.Fisher, J.Conrad

• Univ. of Pennsylvania: J.Klein, K.Lande, A.K.Mann,

M.Newcomer, R.vanBerg

• Univ. of Pittsburgh: D.Naples, V.Paolone

• Princeton Univ.: Q.He, K.McDonald

• Rensselaer Polytechnic Institute: D.Kaminski,

J.Napolitano

• Rochester: R.Bradford, K.McFarland

• South Dakota State: R.McTaggert

• Univ. of Texas, Austin: S.Kopp, K.Lang

• Tufts Univ.: T.Mann, H.Gallagher, T.Kafka, J.Schneps

• Virginia Tech: J.Link

• Univ. of Wisconsin: B.Balantekin, H.Band, F.Feyzi,

K.Heeger, A.Karle, R.Maruyama, W.Wang, C.Wendt

• Yale: B.Fleming, M.Soderberg


Major Project Components

Neutrino Beam. Plan initially for 700 kw beam

with potential for up to 2.3 MW later. Project

Office at Fermilab.

• Near Detectors: for characterization of the

beam. Project Office at Los Alamos.

• Far Detector. Project Office at BNL (water

Cherenkov). NSF Project Office (water

Cherenkov) at U.C. Davis. Project Office (liquid

argon) at Fermilab.

• Underground Lab (DUSEL) Project Office at

U.C. Berkeley/LBL.


Final National

Science Board

Decision: May, 2011

Currently allocated:

NSF $44M,

private/S.D. ~$85M


• 1300 km distance is significant for

determination of neutrino mass hierarchy

• Deep underground site allows rich

physics program in addition to LB

neutrinos


Excavation Plans

October 09

Davis Cavern

Yates Shaft

Existing Drifts

Lab Modules

Ross Shaft

Large Cavities

Excavation Drifts

at 5040L

New Winze

to 7400L

Access Drifts

at 4850L

#6 Winze


Large Cavity, Water Cerenkov Detector

Water: 53m Dia. x 54m vertical,

Fiducial Volume: 50m Dia. x 51m vertical

Utility Rooms

Entrance Drift

at 4850L

Excavation Ramp

to Mid-Levels

Water Level

Large Cavity

Excavation Drift

at Lower Level, 5040L


• four cores in the

region of the first

large cavity

• one core in the

possible location of

two more

• one core in possible

location of a liquid

argon detector hall

• rock conditions are

included in cost

estimates for CDR

• no surprises seen


• Initial coring and rock

strength studies have

been completed and

PDR nearing

completion.

• No “show stoppers”.

Rock strength is very

good

• Costs are within

expectations (or even

slightly less for large

cavity)

• Formal Design Review

at the end of 2010


The age old question…

Y’all find any

CP violation

yet

more

signal!

Not yet

less

background!

…more signal

or less background


Liquid Argon TPC Detectors

• Bubble chamber-like imaging,

detailed event topology, with few

mm resolution.

• Developed over 30 years, and

now being applied in 600 ton

Icarus in Gran Sasso.

• No free protons for nucleon

decay or inverse beta studies.

• Only detector for potential

discrimination of e + from e - at

neutrino factory.

• Assume 100% efficiency for

background rejection and

80% efficiency

13 August 2009 John Learned @ ANT09 28


IMB

3 ktons

Kamiokande

1 kton

SNO

1 kton

Super-Kamiokande

22 ktons


300 kTon + 2.4 MW

Mass Hierarchy

M.Dierckxsens

CP violation

5% background uncertainty

120 GeV 0.5 OA

R.Svoboda, 3 November 2008


100 kTon + 700 KW

Hierarchy

M.Dierckxsens

5% background uncertainty

120 GeV 0.5 OA

R.Svoboda, 3 November 2008


A large liquid argon detector for

one or more of the modules is a

possibility

The Science Collaboration has

been asked by DOE/NSF

JOG to recommend a detector

configuration mix

by September, 2010

A Physics Working Group has

been set up to consider nine

possible reference configurations.

First report: May 26 2010. Final

Draft at INT workshop August

2010.


Liquid Argon versus Water

Cherenkov

• Two major backgrounds for CPV/mass

hierarchy measurement: intrinsic ν e in

beam and misidentification of NC π o .

• A liquid argon detector should be much

better with π o identification. Downside:

technology not as well-developed, cost

and schedule risks not well known.

• A water Cherenkov detector can be made

much larger for more signal. Downside:

poorer resolution on π o background.


ICARUS

• ICARUS: 20 yr

effort 50l 3t

600t

• Bern: LAr TPC w

UV laser “track”

simulator

Long drift test (5m)

Bruce Baller, Fermilab -

DOE Detector R&D Review,

July 8, 2009

37


ArgoNeut running at FNAL

ν interaction with 3 γ conversions

Commissioned 2 weeks

before the accelerator

shutdown

EM Shower

Bruce Baller, Fermilab - DOE Detector R&D Review, July 8, 2009

38


LAr TPC Reconstruction – Two

Track Separation Efficiency (Monte

Carlo)

100% separation

efficiency when track

separation = wire

signal σ

Bruce Baller, Fermilab -

DOE Detector R&D Review,

July 8, 2009

39


A Large Water Cherenkov

Neutrino Detector for DUSEL

Note: the DUSEL detector will

likely be realized in 2-3 modules

The muon rate in the DUSEL detector

will be 1/30 th that of Super-Kamiokande

3

ktons

IMB

22

ktons

Super-

Kamiokande

300 ktons

DUSEL


Improved π 0 /e separation in SK

• 2-R e-like tag (old ring-finder)

• π 0 fitter (improved ring-finder)

Reconstruction efficiency of π 0(%)

100

90

80

70

60

50

40

30

20

10

0

used in

current studies

work to adapt

this to LBNE

in progress

200MeV 400MeV 600MeV 800MeV

pi0 old

pi0 new

e old

e new


Gadolinium Doping

• Sensitivity to neutron capture via 8 MeV

gamma cascade (e.g. M.Vagins, NNN08)

• Inexpensive, low risk. Could be

implemented after construction completed,

no schedule risk.

• Technical challenges:

- material compatibility. Chose materials

that do not contaminate the water.

- water treatment . Remove impurities but

leave gadolinium in solution.

R.Svoboda, 3 November 2008


Photon Economics

• About 50% of the detector cost is expected to

be in photosensors

• Even small improvements can make a big

impact

• Development of light enhancement techniques

underway

• New high QE PMTs are now available – will be

tested in a statistically large sample this year

• Prevention of implosion chain reaction

(BNL+U.S. Navy). This is a possible point for

international cooperation.

• Developments outside Project: waveshifting

dyes, MCP development


• Huge signal for a galactic supernova

• More importantly: very precise knowledge of

the cross-section (~0.2%) for ν e + p -> e + + n

makes the statistics meaningful!

• Double coincidence: zero background (need

Gd)

• Positron spectrum mirrors neutrino

spectrum 10 kpc with 300 ktons

CC ν e

NC ν x

ES ν e

70,000 events

3,000 events

3,000 events


S. Ando, J. F. Beacom and H.Yuksel,

astro-ph/0503321

DUSEL is capable of detecting

a supernova in Andromeda Galaxy

A SN in M31 would

~3-5 events/100 kton

It would be easily

detectable in a large

water detector of

Size ~300 ktons

Background is large

bursts of spallation

products following

a muon-induced

shower

deeper is better


The feeble signal of all SNe

• Sum up

supernovae over

the whole

universe:

Supernovae

• This is detectable

• We can verify our

expectations for

stellar formation

rate at large

redshifts

S. Ando and K. Sato, New J.Phys.6:170,2004.


Diffuse SN FLux

C.L., Astropart.Phys.26:190-201,2006

• Differences due to different inputs/methods

For a Gd-loaded 300 kton WC detector, estimates

range from 6-60 events/year.

C.L., Astropart.Phys.26:190-201,2006, Fogli et al. JCAP 0504:002,2005,

Volpe & Welzel, 2007, C.L. & O.L.G. Peres, to appear soon.

SK background of ~20/year significantly reduced by

neutron tagging. (Beacom and Vagins)


Nucleon Decay

Neutrinos, electrons, photons, and protons

are the only known stable particles

• Stable over what time scale

• Lifetime of universe 10 10 years

• Many theories that try and unite the

known forces of nature into a “Grand

Unified Theory” (GUT) predict that free

protons will decay with lifetimes of 10 30

years or longer


Proton Decay Limits

GOAL: push this

Sensitivity forward

By factor of 10 or more

E.Kearns


The Big Hole

• One large cavity is included in the

scope of DUSEL. DOE/NSF are

cooperating in costing out cavities for

water Cherenkov and liquid argon

detectors.

• Large Cavity Board report: a large 100

kton detector could be built safely and

economically. 150 kton cavities may

also be possible.

• Large Cavity: Three independent cost

estimates


Schedule

• Initial design and costing complete by Fall,

2010

• Detector(s) choice for FD/Science Program

defined by Science Collaboration: Fall 2010

• DOE CD-1, December 2010

• National Science Board, Spring 2011

• Preliminary Design (~CD-2), end of 2012

• DUSEL construction start, 2013

• LBNE construction, 2015-2019 (this could

be earlier depending on DUSEL lab


Summary

• A LBNE experiment is being designed from

Fermilab to DUSEL. This experiment has

been selected as the major Fermilab effort in

the post-Tevatron era.

• The intense neutrino beam would provide an

unequaled opportunity to measure the mass

hierarchy and look for CP violation. The

sensitivity is well-matched to expectations

for current theta13 experiments.

• A very broad program is planned, including

proton decay, precision oscillation

measurements, neutrino astrophysics, and

neutrino cosmology.


Excellent particle identification


Other Experiment

Components

• Electronics: conceptual designs in

progress. Would like further international

cooperation.

• Water transparency: facilities at UCI,

LLNL

• Gadolinium loading: UC Irvine, LLNL,

BNL

• Calibrations: specifications being

developed

• PMT’s: FNAL

• Project Integration: BNL/DUSEL/S4


Water Cherenkov Detector

Design Group

• Argonne NL

• Boston University*

• Brookhaven NL

• Caltech*

• Univ. of California,

Davis*

• Univ. of California,

Irvine*

• Drexel University*

• Duke University*

• Fermi NL

• Lawrence Livermore

NL*

• Univ. of Maryland*

• Univ. of Minnesota

• Univ. of

Pennsylvania*

• Rensselaer Poly.

Inst.*

• Univ. of South

Carolina*

* Funded through S4

• Univ. of Wisconsin*


Excavation Plans

Large Cavity Excavation Sequencing

(LCAB)

Stage 1

•Excavate Top Heading Concurrent with Bottom

Heading

•Excavation and support needs to proceed

sequentially from the center of the cavern out to

the perimeter of the cavern.

•The top drift into the center of the cavern

should be approximately 5 meters or less in

width with the permanent rock support installed

as the drift progresses.

•The sequence could be in approximately 5

meter rings or in pie shaped wedges, but always

proceeding from the center of the cavern

towards the perimeter.


Excavation Plans

Large Cavity Excavation Sequencing

(LCAB)

Stage 2

•Excavate Center Borehole

•Borehole dimension – 10 – 14 ft diameter

•Provides conduit for muck removal as well as

relief for blasting

Bore

Hole


Excavation Plans

Large Cavity Excavation Sequencing

Stage (LCAB) 3

Long hole drilling and blasting of the center

portion of the cavern.

•The dimension of the un-blasted perimeter ring

should be determined by numerical modeling of

stress conditions and assessment of rock joint

patterns.

•The key parameter in defining the perimeter

ring is confining the predicted rock fracture

resulting from ground relaxation to within the

ultimate excavated perimeter of the cavern.

•Other considerations, such as drilling

equipment dimensions, may increase the width

of the perimeter ring but the minimum width

needs to be determined and adhered to.


Excavation Plans

Large Cavity Excavation Sequencing

Stage (LCAB) 4

•The perimeter ring is to be excavated in

benches deep enough to be reasonably

economical but not deep enough to create

failure in the surrounding rock mass due to

stress relaxation at the cavern wall. It is

imperative that the wall excavation support be

installed in a timely manner.

•In all of the excavation sequences proper

controlled blasting techniques must be

employed. The intent of the controlled blasting is

to limit the loosening of the remaining

rock mass. This maximizes the long term

stability of the remaining rock mass under

changed stress conditions and decreases the

likelihood of rock falls


What is CP Symmetry

60

Co 60 Ni * + e - + ν e

B

ν e

e -

½ +

This

5 +

CP reaction seems never to work happens! better 4 + ½ +

B

e +

60

Co

60

Ni *

p ν

p e

4/21/2010 R.Svoboda 73

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