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MAGIC

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.

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MAGIC

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  1. MAGIC Recent AGN Observations

  2. 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

  3. Single Telescope

  4. Stereo System

  5. 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)

  6. EGRET SKY

  7. FERMI Sky Map

  8. TeV Sky Map

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

  10. 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]

  11. 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

  12. 3C279 MAGIC Observations 2007 and 2009 MAGIC observations • December 2008- April 2009 MAGIC observations: rather unfortunate timing • Resulted in non-detection, differential upperlimits:

  13. 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

  14. 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

  15. 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

  16. 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

  17. 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

  18. 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

  19. 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)

  20. 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”.

  21. 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

  22. 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)

  23. 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)

  24. 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

  25. 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

  26. Extensive MWL on M87 in 2008 • MAGIC-HESS-VERITAS joint effort • Coverage 120h / 50nights • HST-1 very unlikely source of the emission

  27. 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!

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