Spyros Tzamarias School of Science and Technology Hellenic Open University

Neutrino Telescopy after the new developments

in Particle and Astroparticle Physics

Spyros TzamariasSchool of Science and Technology

Hellenic Open University

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Sky view of a Mediterranean UnderSea Neutrino Telescope

>75%>25%

KM3NeT coverage of most of the sky (87%) including the Galactic Centre

FOV for up-going

neutrinos shown

From Mediterranean 24h per day visibility

up to declination d~-50°

KM3NeT consortium consists of 40 European institutes, including those in Antares, Nemo and Nestor, from 10 countries (Cyprus, France, Germany, Greece, Ireland, Italy, The Netherlands, Rumania, Spain, U.K)

KM3NeT is included in the ESFRI and ASPERA roadmaps KM3NeT Design Study (2006-2009) defined telescope design and outlined

main technological options Approved and funded under the 6° EU Frame Program Conceptual Design Report published in 2008 http://www.km3net.org/public.php Technical Design Report (TDR) completed => outline technology options for the

construction, deployment and maintenance of a deep sea neutrino telescope http://www.km3net.org/KM3NeT-TDR.pdf

KM3NeT Preparatory Phase (2008-2012) defines final design, production planes for the detector elements and infrastructure features. Prototype validationis under way. Legal, governance and funding aspects are also under study.

Scientific Standing Committee: External Scientific Evaluation Approved and funded by EU under the 7° EU Frame Program

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General KM3NeT lay-out

Primary Junction box Secondary Junction boxes

Detection Units

Electro-optical cableOpticalModule (OM) = pressure resistant/tight sphere cointaining photo-multpliersDetection Unit (DU) = mechanical structure holding OMs, enviromenta lsensors,electronics,… DU is the building block of the telescope

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Design Study TDR - Detection Unit and Optical Module Concepts

• Two different options for OMs and Dus reported in TDR

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Flexible tower with horizontal bars equipped with large PMT OMs

Slender stringVertical sequence of multi-PMT OMs

•Preparatory Phase =>Convergence i.e. DU=Flexible tower, OM=Multi-PMT•Prototype and validation activities crucial for final choice• GOLDEN ROOL: Maximize the Discovery Potential

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DOMBAR Prototype–Storey -

6 m

Mechanical Cable Connection

Rope & Cable Storage

Rope Storage

Bar Frame

Optical Module

Mechanical Interface

2 DOM + 1 BAR = 1 DOMBAR20 DOMBARS = DOMTOWER

The Vertical String Structure IS NOT ROOLED OUT

Fermi LAT Observation – Fermi Bubbles -

• From Meng Su, Tracy R. Slatyer, Douglas P. Finkbeiner Astrophys.J.724:1044-1082,2010

•Large extension (50°lat. 40° long.)• no spatial variation in the g spectrum

“We show below that a cosmic ray population can explain these structures” ………“…Finally, we predict that there should be a region of extended, TeV g radiation surrounding the Galactic nucleus on similar size scales to the GeV bubbles with an intensity up to E-2 Fg(TeV) ~10-9 TeV cm-1 s-1 sr-1 which should make an interesting target for future g-ray studies. Likewise, the region is a promising source for future, Northern Hemiphere, km3-volume neutrino telescope: we estimate (assuming a g=2.0 proton spectrum cut-off 1 PeV)….

The expected neutrino flux for one bubble is

E-2 Fn(TeV) ~ 10-6 GeV cm-1 s-1 sr-1 * 0.34 sr / 2.5 ~ 1.3 10-7 GeV cm-1 s-1

From M. Crocker and F. Haronian Phys. Rev. Lett. 106 (2011) 101102

Gamma flux Single bubble solid angle

From g spectrum to n spectrum

Northd = -15°RA = 243°R =19°

Southd = -44°RA = 298°R =19°

Neutrino generation

homogeneous in a circular region around fixed points

one block of 154 DU

Rosa Coniglione

In Meng Su et al. bubbles are due to relativistic CR electrons that produce gamma through IC process

Galactic Candidate n Sources – SNRs -

Origin of CosmicRays SNR paradigm, VHE g but no conclusive evidence about CR acceleration

RXJ1713-39.43 and Vela JR best candidates

RXJ1713-39.43IF hadronic mechanisms => n spectrum can be calculated from VHE gspectrum ( solid redline Vissani)

Observation at 5 swithin about 5ys with KM3NeT

Hess RXJ1713-39.43

Gamma Ray Bursts

The spatial distribution of the photosensitive area is a critical parameter that affects the discovery potential of the telescope

NIM A 626-627 (2011) S188-S190

Environmental Parameters & Early Discovery Driven Scenario

doi:10.1016/j.nima.2010.09.040 |

Detector Geometrical Layout

154 Towers or 77 TowersEach Tower consists of 20 bars, 6m in length and 40m apartOne MultiPMT OM at each end of the bar. 29% QE

Detectors Footprint

Use WISELY the whole Experimental Information

• Reconstruction Resolution on a track by track basis• Energy Estimation

z

x y

(θm, φm)

ψ

(θ, φ)

x *cos sinx *sin cos

tan2 2V * *

V * * V * *

U x x, y y

1

2V * * V * * V * *V * * 2 4 V * * 2

x

2 U x x

y2 U y y

P() 1

2 x y

2 x2 y

2 e

1

2

x2

x2 y

2

y2

dx dx

Eν<10 TeV

10TeV<Eν<100 TeV

100TeV<Eν<1 PeV

1PeV<Eν

A Neutrino Telescope CAN Measure Energy

NIM A 626-627 (2011) S185-S187

Psignal

angle ( x ,y ) 1

1 e

Rmax

sx2 sy

2

1

2 x y

e

1

2

x2

sx2 y

2

sy2

Pbck

angle ( x ,y ) 1

Reconstructed Energy (log of GeV)

0.5<cos(θ)<0.55

Psignal

energy (Em,m;) from MC

Pbckangle (Em ,m ) from MC

2sign( ˆ N s)lnL0 Ns 0 L 2, ˆ N s

N=0

N=6

N=4

N=8

Discovery Potential (50% Discovery Probability)preliminary

3σThis Method: 1.2x 10-9 E-2 flux for 50% discoveryThis Method without Energy: 1.6x10-9

Binned method: >2.4x10-9

4σThis Method: 1.6x 10-9

This Method without Energy: 2.6x10-9

Atmosphericγ=2γ=1.8 (re-weighted))

Log(E/GeV)

L ,Ns i1

N total

Pi x ,y ,Em,m;,Ns

L0 Ns 0 i1

N total

Pi x ,y ,Em ,m;Ns 0

2sign( ˆ N s)lnL0 Ns 0

L ˆ , ˆ N s

Sign

al E

vent

s

Spectral Index

24 Signal Events on Top of Background 15 Signal Events on Top of Background

Spectral Index

Sign

al E

vent

s

Spec

tral

Inde

x es

timati

on a

ccur

acy

Signal events on top of Background

Final Remarks• We gain a factor of 2 in discovery potential by

using more of the information offered by the data ! We can make it better…

• The Design of KM3 is not finished yet

Optimize the layout for fast discovery Galactic Extended SourcesGRBs, AGN, GKZDark Matter? UHE Atmospheric Showers ?