CREDO science case D. Góra for the CREDO Collaboration Institute of Nucler Physics PAS, Cracow

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Topics

1) CRPropa standard / exotic CRE: conditions

2) looking for Sun Cosmic Ray Ensambles

3) clusters in time: any time scale suspected

5) search for correlations: cosmic / GMF / weather / sun activity / seismic effects

4) Integration of data from different experiments: Credo monitor

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Topic 1: Preshower in vinicity of Sun

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Example of CRE : Preshower in vinicity of Sun

Y [km]30� 20� 10� 0 10 20 30

Z [m

]

0.15�

0.1�

0.05�

0

0.05

0.1

0.15

1

210

410

610

810

1010

1210

1410

1610

18101910

E [eV]

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Finding point sources in the sky means to locate an excess of events from a particular direction over the background.

The signals events my present additional features: different energy spectrum or time structure

- the angular uncertainty of event - the angular distance of event from source

# E

vent

s Energy

Signall Backgroundl

Topic3: Basic concept of point-source search filter

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htempEntries 10000Mean 1.542− Std Dev 0.5509

log10(TS=min doublet duration)5− 4− 3− 2− 1− 0

Cou

nts

1

10

210

htempEntries 10000Mean 1.542− Std Dev 0.5509

7

RESULT: p-value as the fraction of events below TSdata

TSdata

TSdata

background events

Test Statistics (TS) Data distribution Scrambled maps

TS := doublet duration*

*for other multiplets different defini tions assumed

TS1

time TS2

TSN

N=10 000

S1

S2 P-value=--------- S1

S1 + S2

Simple method: search for time cluster

Slide 8 8 TS distribution for no signal events in data sample

General method: an unbinned maximum likelihood

TS distribution for no signal events in data sample

Method (J. Braun et al., Astropart. Phys.33:175,2010) Space probability density function Energy probability density function

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Topic4:

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Topic 5:

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Varia:

... and gamma-ray astronomy