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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
MAGIC observations
December 2008- April
2009 MAGIC
observations: rather
unfortunate timing
Resulted in nondetection, differential
upperlimits:
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 gammaray 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 20062008 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 nondetection=> 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-HESSVERITAS 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!