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"Cosmogenic neutrinos detection"
P. Spillantini, INFN and University, Firenze

Round Table discussion "Exciting neutrino: from Pauli, Fermi and Pontecorvo to nowadays prospect" 16°th Lomonov conference on Elementary Particle Physics, Moscow 2228 August, 2013
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: om fr ed nu ti on C

Observation of Ultra High Energy neutrinos
Sergio Bottai, INFN, Firenze, Italy Piero Mazzinghi, INOA, Firenze, Italy Piero Spillantini, University and INFN, Firenze, Italy

11th Lomonosov Conference on Elementary Particle Physics Moscow, August 2127, 2003
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rom f ed u ntin Co

:
10th Lomonosov Conference on Elementary Particle Physics, Moscow, 2329 August 2001

From the `Extreme Universe Space Observatory' (EUSO) to the `Extreme Energy Neutrino Observatory'

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Cosmogenic neutrinos component Protons coming from distances >20-50 Mpc interact with the CMB (GKZ effect) producing pions, and finally neutrinos. Protons with E>1020eV interact several times before degrading under the GKZ cut-off producing many e and neutrinos. The energy of produced neutrinos is 1018eV or more

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This is the "less unprobable" neutrino component expected at the extreme energies. It is not "model dependent"
(i.e. it only depends from UHECR E
max

and the proton source distribution)

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Fig. 2.1 ­Artist view of the EUSO concept. The shower development occurs in the atmosphere layers below 3040 km a.s.l.; the isotopic fluorescence emission is proportional at any depth to the number of 9 charged 9/8/2013 particles (mainly electrons) present in the shower front: Ne EeV / (1.4x10 ). The UV yield is 4 photons per meter of electron track, almost independent from air pressure and temperature.

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The most complete work was (@<2004) "UltraHigh Energy Neutrino Fluxes and Their Constraints"

(Kalashek, Kuzmin, Semokov, Sigl)

[arXiv:hepph/0205050 v3 13 Dec 2002]

[Model consistent with gamma's and UHECR data (Fly'sEye, Haverah Park, Yakytsk, AGASA)]

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p + +(1232) N



e

EUSO

min

Max

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......................................................................................

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p + +(1232) N



e

EUSO EUSO x 10

min

Max

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Is it possible to increase the number of detected neutrino events?
(EUSO-like from ISS)

-Decrease the energy threshold (5 x 1019eV 1018eV) x 1.5 by improving the sensor efficiency (0.20 0.50) by improving the light collection (pupil 2m 6m) x 9 (what implies reflective systems and modularity) -Increase the target volume -by increasing the FOV (60° .......

but limited to 90є by attenuation by air and by distance

140.8°)

(x 90) x3

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p + +(1232) N



e

EUSO EUSO x 30

Max Extreme min

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One optical system (EUSO like) H (km) Total FoV (o) Radius on ground (km) Area on ground (103km2) Target volume (km3) Pixel on ground (km * km) number of pixels) (.8x.8 km2) Pupil diameter (m) Photo detection efficiency E threshold (EeV) Proton events/year, GKZ + uniform source distrib. with Ep >100 EeV) Neutrino events per year ( min) Neutrino events per year ( Max) 400 60 235 173 1730 0.8 x 0.8 270k 2.0 2.0 20% 50% 50 30 1200 100 0.2 4 4000 100 0.4 6 Multimirror 400 90 400 503 5030 0.8x0.8 786k 6.0 50% 3 300k 290 4.5 14

4.0 50% 8 35k 290 1.5 12

10.0 50% 1.2 2000k 290 10 18

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After 2004: new data: GZK confirmed + (?) primary UHECR heavier than p (?) FermiLAT

Ahlers et al. bestfit, consistent with HiRes spectrum and FermiLAT diffuse gamma's
`GZK neutrinos after FermiLAT diffuse photon flux measurement' M.Ahlers et al., Astropart. Phys. 34, 106 (2010)

Ahlers and Halsen updates of lower limits (normalization to Auger data)
`Minimal Cosmogenic Neutrinos' arXiv:1208.4181v1, 21 Aug 2012

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K+al p Max K+al p extreme

(A+H (A+H p 10%) p 1%)

A+H p

A+al p best fit

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K+al p Max K+al p extreme

IC86 (10years) AUGER (Xyears) ARA (3years) 30xEUSO (1year)

(A+H (A+H p 10%) p 1%)

A+H p

A+al p best fit

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K+al p Max K+al p extreme

IC86 (10years) AUGER (Xyears) ARA (3years) 30xEUSO 1 year 800 km 1200 km

(A+H (A+H p 10%) p 1%)

A+H p

A+al p best fit

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IC86 (10years) AUGER (Xyears) ARA(3years) 30xEUSO 1 year 800 km 1200 km

p He Fe Si N

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One optical system (EUSO like) H (km) Total FoV (o) Radius on ground (km) Area on ground (103km2) Target volume (w.e. km3) Pixel on ground (km x km) number of pixels) (.8x.8 km2) Pupil diameter (m) Photo detection efficiency E threshold (EeV) Proton events/year, GKZ + uniform source distrib. with Ep >100 EeV) Neutrino events per year ( min) Neutrino events per year ( Max) Neutrino events per year (bestfit) Neutrino events per year (px100%) Neutrino events per year (px10%) Neutrino events per year (px1%)
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Multimirror 400 90 400 503 5030 0.8x0.8 786k 4.0 50% 8 35k 290 1.5 12 0.3 0.035 0.0025 0.0002 6.0 50% 3 300k 290 4.5 14 1 0.15 0.015 0.003 10.0 50% 1.2 2000k 290 10 18 2.5 0.5 0.08 0.025 800 90 800 2000 20000 0.8x0.8 3000k 12 50% 3 1200K 1180 18 56 4 0.6 0.06 0.012 1200 90 1200 4500 45000 0.8x0.8 7000k 18 50% 3 2700k 2600 40 126 9 1.3 0.13 0.027
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400 60 235 173 1730 0.8 x 0.8 270k 2.0 50% 30 4000 100 0.4 6 0.05 0.002


h= 1200 km
Px100% Px1% Px10%

100 10 1
best fit

1

min

Max

sEuso x 2.5 Ь=10 Ь=30
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sEuso x 2.5 sEuso x 2.5 Ь=6 Ь=18 Ь=4 Ь=12

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h= 400 km (EUSO =2m)


Conclusions:
Cosmogenic neutrino detection is crucial for the neutrino entering the scene as a new instrument for Astrophysics, Cosmology and Particle Physics New data have diminished their foreseen flux by at least 2 orders of magnitude If the p component in UHECR is abundant, complex large optical systems can observe cosmogenic neutrinos from space, but high altitude orbits could be necessary

If the heavy nuclei component prevails its `daugter' cosmogenic neutrino flux is out of reach for any system. (also because the neutrino energy becomes too small for detection by radiosystems) In next few years the increase of UHECR statistics and the definition of their charge should help in clarifying the situation.

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Could you follow me? Thank you!

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golden

Fluorescence only

Xmax Select

Shape

.

Select.

Rejection > 10

-4

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100 Area of the calotta (106 Km2 ) 15 90 80 70

Florescence light attenuation as a function of the FoV
Attenuation factor (respect to Nadir)

10

attenuation due to geometry attenuation due to atmosphere *

Area of the calotta Area seen by EUSO

10

60 50 40

(EUSO)

TOTAL attenuation
0.5

5

30 20

(EUSO x 3)
10

(EUSO)
0 500 30°45°
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(EUSO=1.7x106km2)
1000 60° 65° 1500 2000 70° distance from Nadir (Km) 1/2 FoV
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*Considered

from the sea level

HORIZON


Resolution of 5 m EDP reflecting system INOA
40000 40000 8 36000 36000 7 32000 32000 6

Spherical mirror with ± 25° FOV

28000 28000 24000 24000 20000 20000 16000 16000 12000 12000 8000 8000 4000 4000 s pot r adius s iz e (m icr on)

5 gr es ( km )

4

Spherical mirror with ± 15° FOV
3

Spherical mirror + Schmidt corrector
2

Spherical mirror + Schmidt corrector optimized at marginal field angles
1

Aspherical mirror + Schmidt corrector
0 0,0 0,0 5,0 ,0 10,0 FOV ( de g) 15,0 20,0 20,0 0 25,0 25,0

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Active thin mirror concept
Ideal form

Strutture is deformed and deforms the membrane

Attuators compensate the deformation

The optical surface is coupled to a structure of light rigid supports by a matrix of actuators, adjusted on the measurements of the wave front

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deployment d

trigger data handling telemetry

single m ir field of ror view

sensors
total field of view
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