Microquasar searcheswith MAGIC

Núria SidroInstitut de Física d’Altes Energies (IFAE)

Barcelona

International School of Cosmic Ray AstrophysicsErice, Sicily, 10 July 2004

What is a microquasar?Microquasar = X-ray binary star displaying relativistic

Radio-jets.

Double-star system =

collapsed object (BH or NS) + normal star

Mirabel &

Rodriguez, Nature 1994

GRS1915+105

Ejected plasma at apparent Superluminal motion

Mirabel et al, Nature 1992

1E1740.7-2942

Quasar Microquasar

MBH ~ 108M

T ~ 105K

accretion luminosity

OPTICAL & UV

Radio jetsMillion LY

time scales of years

MBH ~ 10M

T ~ 107K

accretion luminosity

X RAY

Radio jets few LY

time scales of minutes

Observed Morphological & Physical similarities

multi-wavelength

Compact jetsRadio & Gamma

IR & UV

multi-wavelength

(Bosch-Ramon et al, A&A 2004)

Gamma-rays

X-raysUVOpticalIRRadio

Model:•Leptonic jet•Strong magnetic field•Dominant stellar IC

MAGIC sensitivity

μQ EGRET sourcesHigh-mass μQ have been proposed as the counterparts of the variable EGRET sources of the galactic plane.(Kaufman Bernadó et al. 2002, Romero et al. 2004)

168 Unid -> some could be μQ

LS

I+61 3

03

AX

J1639.0

-464

2LS

5039

μQ EGRET sourcesLSI+61 303

For Eth <100GeV Observation Time for 5σ is < 50 hours

EGRET detection

EGRET extrapolati

on

cut-off Model

MAGIC sensitivity

(Bosch-Ramon et al)

μQ EGRET sources

130 High150 Low

Mass X-ray binary sources

16 μQ in our GalaxyBeing

observedby MAGIC

May/2004Flare ASM ( 2-10 KeV)

• LSI +61 303• SS 433• AX J 1639.0-4642• Cygnus X1• Cygnus X3• GRS 1915+105• XTE J118+480

Northern Hemisphere

Summary

1. μQ present a broad band spectrum.

2. Gamma-rays can arise in IC processes when the

relativistic e- of the jet interact with external

photons from the massive companion.

3. The obtained results for the μQ LS 5039, LSI +61

303 and AX J1639.04642 point towards a

population of HMXB μQ, as counterparts of low

galactic latitude unidentified EGRET sources.

4. MAGIC is ready to discover a new population of μQ

emitting VHE Gamma-rays.