Astroparticles (CR’s & ) in the nearby universe& Virtual Observatory… one Universe, two worlds

Giuseppe Longo1,2,3 & Gennaro Miele1,2

1-Department of Physical Sciences – University Federico II Napoli2 - INFN Italian Institute of Nuclear Physics – Napoli Unit

3 - INAF Italian Institute of Astrophysics – Napoli Unit

longo@na.infn.itmiele@na.infn.it

Part I

Why do astroparticles need V.Ob. ?

….. Because they look at nearby universe(D<100/200 Mpc)

10 TeV

1 TeV100 GeV

Photon interactions at TeV energies give a gamma horizon comparable in size to the GZK horizon

The main interaction is: e+e-

Pair production with e+e- cascading.

The gamma photons scatter on the extra- galactic background light.

kneeknee

anklanklee

UHECR

GZK horizon: CR (E>1018.5 eV) interact with CMB photons and decay

No UHECR’s from D > RGZK ≈ 100 Mpc

UHECR

gamma

Nearby universe means large f.o.v. (i.e., surveys)

for statistics

Ground based gamma ray Cherenkov telescopes

Cosmic ray showers and Hybrid detectors

….. Because are going through a similar technological breakthrough

(D<100/200 Mpc)

gamma-ray observatories (with small field-of-view)

CANGAROO III(Australia & Japan)

Spring 20044 telescopes 10

meters ØWoomera, Australia

Windhoek, NamibiaHESS

(Germany & France)

Summer 20024 (16)

telescopes12 meters Ø

Roque delos Muchachos, Canary Islands

MAGICMAGIC(Germany, Spain, Italy)(Germany, Spain, Italy)

Summer 2003Summer 20031 telescope 17 meters 1 telescope 17 meters

ØØMontosa Canyon,Arizona

VERITAS(USA &

England)2005?

7 telescopes10 meters Ø

+ Wide-angle instruments surveying ~ 2-3 sq. deg.

“Threshold”Sens. (1 y)Milagro ~ 2 TeV ~ 0.5 CrabTibet III shower array ~ 3 TeV ~ 1 CrabARGO YBJ 0.5 – 1 TeV ~ 0.5 Crab Crab signal

Tibet array

“Keck mirror segment” equivalent

UHECR’s telescopes look really WEIRD!

UHECR - The Pierre Auger Giant Array Observatory

1600 tanks + 24 Fluorescence Telescopes

3000 events yr-1 with energies above 1019 eV 30 events yr-1 above 1020 eVSampling on nanosecond scale; Sampling on nanosecond scale; events last events last 30-100 ns30-100 nsAngular resolution 30’ < p.r. <1.5°Angular resolution 30’ < p.r. <1.5°

ns!ns!

Gamma rays begin to approach optical resolution

But:

Objects visible in gamma are not always visible in optical light

30 a

rcm

inUHECR’s are still far from itAngular resolution is small

p.r. > 30 ‘

Magnetic fields -> 1.5° < Deflection < 5.0°

In one resolution element,Up to 50.000 potential sources

One universe

Energetic objects (GRB, SN, BH, AGN, etc.)

Dark Matter composition & distributionCosmological constantsCorrelation functions

&c.

Two worldsAstronomy

Large redshift range

Avalanche of complex dataMissing data

HeterogeneousLow time resolution

High angular resolutionFew large simulations

V.Obs. standardsProblems known

Astroparticles

Local Universe

Fewer and/or simpler dataSparse and uneven sampling

Heterogeneous Medium/high time resolution(Often) low angular resolutionVery many small simulations

No standardsProblems to be explored

Huge technological developmentLarge international collaborations

Proprietary dataSecurity issues

Many common science goals Common methodology of research

Part II – an example

Identifying the sources of UHECR

Correlation of the Highest-Energy Cosmic Rays with Nearby Extragalactic Objects by The Pierre Auger Collaboration*

Using data collected at the Pierre Auger Observatory during the past 3.7 years, we demonstrated a correlation between the arrival directions of cosmic rays with energy above 6 x 1019 electron volts and the positions of active galactic nuclei (AGN) lying within 75 megaparsecs. We rejected the hypothesis of an isotropic distribution of these cosmic rays with at least a 99% confidence level from a prescribed a priori test. The correlation we observed is compatible with the hypothesis that the highest-energy

particles originate from nearby extragalactic sources whose flux has not been substantially reduced by interaction with the cosmic background radiation. AGN or objects having a similar spatial distribution are possible sources.

Science 9 November 2007: Vol. 318. no. 5852, pp. 938 - 943

Hundreds of citations in less than 2 months

ground zero for a very harsh debate

mainly Related to how to integrate astroparticle data with astronomical ones !!

Events(t, E, , )

Deconvolution for magnetic fields

Reconstructed Events(t, E, ’+, ’+)

Matched cataloguesMatched catalogues

Source Source Identifications?Identifications?

Astroparticles world

V.Obs. world

Problems:

1. Low angular resolution of UHECR data(1 event -> hundreds possible sources)

2. Poor knowledge of galactic/extragalactic B fields

Statistical approach to be preferred

Deterministic approach

Ill posed problem GRID

Astronomical cataloguesAstronomical catalogues

Experiment 1: •UHECRs sources follow the distribution of LSS

(either AGN in clusters or WIMPS in DM haloes)•GZK is on/off (quite a consequence…)•Standard propagation of protons•Magnetic fields not very strong

Since you cannot identify sources, you must work on correlations of asrrival directions

2006, doi:10.1088/1475-7516/2006/01/009 (astro-ph/0510765)

Propagation of protons

IRAS - PSC

15.000 galaxies with spect. z

Production of protons

Resulting UHECRs flux integrated from a lower threshold of 5x1019 eV

Ecut=30 EeV Ecut=50 EeV

Ecut=70 EeV Ecut=90 EeV

GZK filter (D<200 Mpc)Bright galaxies selection biases, etc…

0 50 100 150 200 250 300 350

-75

-50

-25

0

25

50

75

How many How many events to events to detect detect

anisotropiesanisotropies? ?

Auger aperture functionAuger aperture function

Montecarlo simulations isotropic Montecarlo simulations isotropic distribution of eventsdistribution of events

200 eventsISOISO

LSSLSS

93 events compatible withIRAS-PSC

This function vanishes if any of P or 1-P vanishes and has the theorethical maximum value of 1/4. So, the higher its value the more consistent the data are with the underlying hypothesis.

1818

W

z

3TeV1TeV

3GeV

Window Function

=

Combine W(E,z) and survey

+

Synthetic sky maps(low-l angular powerspectrum)

Astronomical cataloguesAstronomical catalogues

Filter on astronomical cataloguesFilter on astronomical catalogues

Specific BoK’s of Specific BoK’s of candidate sources candidate sources

convolution for galactic magnetic fields

Events(t, E, , )predictions

Simulations/convolution extragalactic fields

comparisons

Falsification/validation Falsification/validation BoK’s/HypothesesBoK’s/Hypotheses

GRID

Statistical approach

Astroparticles world

V.Obs. world

Specific candidatesGZKselection effects, etc.

Radio data etc.

Instrumental signature

Conclusions ?

•Standards (for integration with VO & for simulations) for data federation

•Visualization and analysis tools

•Access to multi-epoch data

•Easier access to astronomical knowledge