Observations of 3C 279 with the MAGIC telescope

1. Observations of 3C 279 with the MAGIC telescope M.Teshima1, E.Prandini2, M.Errando, D. Kranich4, P.Majumdar1, M.Mariotti2 and V.Scalzotto2 for the MAGIC collaboration 1) Max-Planck-Institute for Physics, Germany 2) Department of Physics, University Padova, INFN, Italy 3) IFAE Barcelona, Spain 4) ETH Zurich, Switzerland

2. 3C 279 (z = 0.538) • EGRET brightest AGN • Gamma-ray flares in 1991 and 1996 • Apparent luminosity ~ 1048erg/s • Fast time variation △T ~ 6hr in 1996 flare (Wehrle et al. 1998) • Typical OVV quasar (Optically violent variable) • Categorized as a FSRQ • Superluminal motion(Wehrle et al 200) • βapp ~ 4.8~7.5,γ~ 20 • z = 0.538 Wehrle et al. 2000 Kniffen et al. 1993 EGRET 1991 EGRET 1991

3. 3C 279 Flare in 1996 Wehrle et al. 1998 EGRET Wehrle et al. 1998

4. SSC+EC / Hadronic Wehrle et al. 1998 Sikora et al. 1998 MAGIC Sikora et al. 1998

5. EBL Absorption Pair Creation; γHE＋γEBL e+ + e- Stecker et al. 1992

6. MAGIC Telescope New technologies to lower the threshold energy 17m diameter world largest cherenkov tel. 0.1°High resolution camera Hemispherical PMT with enhanced QE Analogue signal fiber transmission Current MAGIC-I Performance Fast rotation for GRB < 40secs Trigger threshold ~50GeV Sensitivity ~2% of Crab (50hrs) Angular resolution ~0.1 degrees Energy Resolution 20-30%

7. MAGIC Telescope 85m New technologies to lower the threshold energy 17m diameter world largest cherenkov tel. 0.1°High resolution camera Hemispherical PMT with enhanced QE Analogue signal fiber transmission Current MAGIC-I Performance Fast rotation for GRB < 40secs Trigger threshold ~50GeV Sensitivity ~2% of Crab (50hrs) Angular resolution ~0.1 degrees Energy Resolution 20-30% MAGIC-II is under construction and will be completed in the fall of the next year Improve sensitivity by a factor of three Effectively lower the threshold energy

8. Observation of 3C 279 with MAGIC • Observation • In the period of January - April 2006 • Observation of 9.5hrs • Zenith angle range is between 32 and 40 degrees  relatively high threshold of 120GeV • Analysis • 4 independent analyses have been done • Standard analysis and standard quality cut • Relative time image cleaning (lower threshold) • All results are consistent • Here, preliminary results will be presented

9. Sky-map and alpha ploton 23rd Feb 2007 80-220 GeV Preliminary Sky map around 3C279 Preliminary Preliminary E> 220 GeV Preliminary Preliminary

10. 3C279 VHE gamma-ray light curve Intra-night LC Preliminary Preliminary Optical light curve

11. Extragalactic VHE-sources (19) Big progress in AGN study from z ~ 0.2 to z = 0.538 New HBL 1ES1011+496 See the presentation by D. Mazin

12. Extragalactic VHE-sources (19) Big progress in AGN study from z ~ 0.2 to z = 0.538 New HBL 1ES1011+496 See the presentation by D. Mazin

13. Summary • VHE gamma-ray emission from 3C 279 was discovered by MAGIC • New class of source FSRQ, OVV-quasar • The VHE flare at 100GeV was observed on 23 February in 2006 • 6.1 sigma below 220GeV, and 5.1 sigma above 220GeV • The survey distance is extended up to z = 0.538 by MAGIC telescope • Big jump toward the deep Universe! • Study of Energy spectrum • may deliver a stringent constraint on EBL and acceleration model • Analysis is ongoing; We need very careful understanding of systematic uncertainties in the energy determination

14. Thanks

15. Blazar Sequence FSRQs LBLs HBLs Fosatti et al. 1998 Ghisellini 2003

16. Collection efficiency for VHE Gamma Rays Low Energy Bin High Energy Bin

17. 3C 279

18. Will not showEnergy Spectrum