56 / MeV ] ) [ 10 ( E φ ν

Neutrinos! Part 2

OlleEngdegård

follekth.se

August23,2007

ground radiation

OlleEngdegård2007 Neutrinos!Part22/8

Dire t: Measuretheneutrinowind,e.g. withtworotatingequaldensitymasses

with dierent ross-se tions(beyondpresent te hnology) 1

A B

Persistent Magnet Suspension Magnet Laser Resonator

Neutrino Target

Balancing Mass

1

hep-ph/0301157

Proposed methods for measuring the osmi neutrino ba k-

ground radiation (2)

Indire tintera tion withotherhighenergyparti les:

1. Leta eleratorbeamsintera twith thereli

ν

future a eleratorenergiesandluminosities)

2. Look fordipsin theUHE osmi neutrinospe trum(possible,butunlikely

with todaysneutrinodete tors)

3. Look for super GZK protons/photons from Z-bursts, se ondaries from

intera tionsbetweenUHEandreli

ν

ReallyIndire t:

1. UseWMAPdata. (Anything anbedonewithWMAPdata.) Flu tuations

in the neutrino ba kgroundis laimedwith WMAP and luster datafrom

SloanDigitalSkySurvey.

2

2

Phys. Rev.Lett. 95,011305(2005)

More details on neutrino emission from supernovae and lessons

from SN1987A.

■ ^{Spe trum should bealmost thermal, with} orre tions forneutrino mixing,

νν

■ ^{Expe t}

E

< E

< E

ν

■ ^{Averageenergiesaround11-26MeV}

■ ^{First 10ms during ollapse,}

∼ 10

ν

by

∼ 10

e¯ e

■ ^{Neutrinoswillemergebeforeanyphotons}

■ ^{Theenergies ofdierentavourswill beroughlythesame.}

from SN1987A.(2)

OlleEngdegård2007 Neutrinos!Part25/8

0 10 20 30 40 50 60

E_ν [ MeV ] 10^-3

10^-2 10^-1 1^-1 10.

φ ( Eν) [ 1056 / MeV ]

Kam-II CombinedIMB Model

Inferred neutrino emission spe tra

from Kam-II, IMB and both. The

shaded shape is a Fermi-Dira spe -

trumwith anoni alneutrinoemission

parameters (average energy

E

= 15

L = 5 × 10

(astro-ph/0702613)

from SN1987A.(3)

OlleEngdegård2007 Neutrinos!Part26/8

■ ^{Conrmed mu h about stellar ore ollapse models: Rough energies,}

times ale,timingvsphotons.

■ Gravitationonneutrinosworksasexpe ted

■ ^{Variouslimits,e.g. mixingangle,}

∆m

■ ^{In 1987, they ruled out neutrino de ay as solution to the solar neutrino}

problem

■ ^{Theneutrino eventsfrom 1987arestillanalysedtounderstandsupernovae}

andthingslike:

■ ^{Why did the Kam-II events have only half the average energy than the}

IMB's? Itwasalso lowerthanexpe tedfrom theory:

3

Expe ted ba kground + signal,

dashed is the 12 KII Gaussian en-

ergydistributions

3

astro-ph/0608399

Compare the Super-Kamiokande and SNO neutrinodete tors

Super-K:PureH2^{O,forlowenergiessensitiveto}

ν

+ e

→ ν

+ e

low ross-se tionfor

ν

ν

SNO: HeavywaterD2^{Oalsosensitiveto}

ν

+ d → p + p + e

ν

+ d → p + n + ν

NCisequallysensitivetoallavours andneutronabsorbtionismademore

e ientwithChlorineinNaCl(2tonnesin1ktonne tank).

SNOlaterhad

3

Heproportional oun-

ters for dete ting the thermal neu-

tronsinsteadofNaCl.

(nu l-ex/0309004)

The prin iples of a ousti neutrino dete tion.

■

∼ 10

µ

τ

leptonisundete table.

■ ^{The hadron shower deposits most of the energy in a ylinder 20 m long}

with20 mradius. Showerdevelopsinstantaneously omparedtothesound

speed.

■ ^{Allenergywill heatthewaterlo ally,expandingitand reatingapulse.}

■ ^{Soundwavesat10-100kHzhas an}attenuationlengthof

∼

■ ^{Thesound anbedete tedwith}o-the-shelf hydrophones

■ ^{Tests are being arried out in sea water and south pole i e (where noise}

from windandpeople ismu hlower):

◆

rows7hydrophones fromUSNavy,Bahamas.

◆

◆

(Mediterranean)

◆