MAGIC

Recent AGN Observations

The MAGIC Telescopes

Located at La Palma, altitude 2 200m

First telescope in operation since 2004

Stereoscopic system in operation since 2009

moonlight

and twilight observations

Single Telescope

Stereo System

MAGIC stereoscopic system

Low energy threshold 50 GeV (25 GeV with sumtrigger): allows observations of distant universe and overlap with Fermi

FoV 3.5 degrees

Sensitivity 0.8% Crab in 50h (>250 GeV)

Angular resolution 0.07 degrees (>300GeV)

Energy resolution ~16% (E>300GeV)

EGRET SKY

FERMI Sky Map

TeV Sky Map

KVA Telescope

• Tuorla is using remotely our KVA telescope which is located physically on La Palma, very close to MAGIC

Flat-spectrum radio quasar 3C279

Most distant VHE gamma-ray emitter with z=0.536, discovered by MAGIC in 2006 (Albert et al. 2008, Science)

Re-observed in 2007 and 2009 (with MAGIC-I only), no new limits on EBL (the EBL modeling has improved greatly in past two-three years, it is not so much free parameter anymore), but interesting results for blazar physics.

Aleksić et al. 2011 A&A accepted [arXiv1101.2522]

3C 279 MAGIC observations 2007 and 2009

In January 2007 triggered by optical outburst

Tuorla blazar monitoring lightcurves available @ http://users.utu.fi/kani/1m

3C279 MAGIC Observations 2007 and 2009

December 2008- April 2009 MAGIC observations: rather unfortunate timing

Resulted in non-detection, differential upperlimits:

MAGIC observations

Optically triggered discoveries

In the past: Mrk180, 1ES1011+496, S50716+714; only for S50716+714 it was possible to show that during the optical outburst the VHE gamma-ray flux was higher than in previous MAGIC observations at low optical state.

Also 3C279 observations were triggered by high optical state, also some not-optically triggered discoveries have taken place in optical high state.

New ones: B3 2247+381 in October 2010 and ON 325 in January 2011

BL Lac object B3 2247+381

candidate BL Lac object at z=0.119

X-ray bright HBL=> good candidate for TeV emission

Added to Tuorla optical blazar monitoring program in 2006, first 4 years showed hardly any variability

Hard spectra in Fermi range: candidate TeV source

Optical outburst in autumn 2010, trigger to MAGIC in the end of September 2010

Swift ToO observations

Optically triggered discovery of VHE gamma-ray emission from B3 2247+381

9.3 hours of MAGIC observations resulted in the discovery of VHE gamma-ray emission from the source with 5 sigma

In total ~20 hours were collected

Flux ~2%Crab (below previous upper limit)

Paper in preparation

ON325 = 1ES1215+303

HBL at z=0.130 (or 0.237)

TeV blazar candidate from Costamante&Ghisellini (2002), appeared also in Fermi candidate list in 2010

Monitored in optical since 2003: has shown many fast optical flares

Has been previously observed with MAGIC (several times)

In high optical state in January 2011, triggered MAGIC and Swift observatons

Optically triggered discovery of VHE gamma-ray emission from

ON 325 MAGIC ToO observations

started on January 2nd 2011

5.5 hours of MAGIC observations resulted in ~5sigma detection: ATel #3100

In total >20 hours were collected

Paper in preparation

HBL 1ES 0806+524

HBL at z=0.138

Candidate TeV blazar from the Costamante&Ghisellini list, detected by VERITAS in 2006-2008 with flux ~1.8%Crab, “little or no measurable variability” was found

Source was showing very prominent and very bright flare in the optical bands since October 2010

The MAGIC observations were finally accepted in February 2011

Optically triggered observation of 1ES 0806+524

MAGIC observation on 24th of February (3.3hours) resulted in detection with >6sigma, preliminary analysis gives flux estimation of ~5.6% Crab

Observations on 23rd of February resulted in non-detection=> day scale variability

Analysis of the whole dataset (~20h) is ongoing

Also Swift observations were triggered, high X-ray state (ATel#3208)

Do optical triggers work?

Yes, they do... at least most of the time and for most of the objects (many HBLs, some LBLs and 3C279)

But it is difficult to prove

And in best studied sources (like Mrk421 and PKS2155-304) the activity in these two energy regimes seems to be connected only “occasionally”.

Not optically triggered discovery: MAGIC J 2001+435

• Was observed because was identified as one of the best candidates for VHE gamma-ray emission from the list of candidate sources

Is identified with MG4 J200112+4352, HBL at unknown redshift

Detected on one night only 16th July 2010

Announced with astronomers telegram #2753, paper in preparation

Best studied northern TeV sources: Mrk421, Mrk501 and M87

Two near-by TeV blazars Mrk421 and Mrk501 (z=0.03), high energy peaking BL Lacs

The brightest TeV sources so obvious candidates for any deep study involving VHE gamma-ray energies

Long term monitoring with MAGIC and extensive MWL campaigns in Fermi era.

M87, the nearby radio galaxy

Long-term collaboration between MAGIC-HESS-VERITAS to monitor the source in VHE gamma-rays in coordination with other instruments from different wavebands (VLBA, X-rays)

Long-term monitoring

To study: un-biased statistics of different flux levels, spectral properties in different flux states, correlations with other wavelengths and determination of flare probabilities

Trigger ToOs (self-triggers, other IACTs, other wavelengths)

Sources to be monitored need to be bright: MAGIC has been regularly monitoring Mrk421, Mrk501 and 1ES1959+650 since 2006 (but observations since 2004)

Results for Mrk421 The lightcurve

has 119 daily averaged flux data points

Variable in short and long timescales

Clear correlation with X-rays

Hsu et al. 2009, ICRC, Lodz

The extensive MWLs

Despite the decades of study the spectral energy distributions were still rather poorly characterized

With Fermi on-board it is finally possible to study the full SED from radio to VHE gamma-rays

Extensive coordinated MWLs since 2009

Extensive MWL on M87 in 2008 MAGIC-HESS-VERITAS

joint effort

Coverage 120h / 50nights

HST-1 very unlikely source of the emission

Summary and outlook

The VHE gamma-ray emission from flat-spectrum radio quasars: fast variability (in time scale of days for 3C279 and in time-scale of ~10 minutes for PKS1222+216)

Optical triggers work well, although connection between optical to VHE gamma-ray high states is not proved yet.

Improved sensitivity has allowed new discoveries of sources: important for population studies

Extensive MWLs provide important insights into AGN jets

MAGIC stereoscopic system is performing well and we expect many more interesting results to come!