Status of the MAGIC telescopes

Transcription

1 SNOWPAC 2010 Status of the MAGIC telescopes Pierre Colin for the MAGIC collaboration Max-Planck-Institut für physik (Munich)

2 Status of the MAGIC telescopes MAGIC-1 MAGIC-2 Outline: Recent results of the phase I ( ) Status of the phase II (since fall 2009) Prospects

3 MAGIC phase I World Largest IACT 17 m diameter 3.5 FOV 577 pixels 2 GSample/s Repositioning <40s air shower Performance Energy threshold: 55 GeV (pulsar trigger: 25 GeV) Sensitivity: 1.6% Crab in 50 h Angular resolution: 0.1 Energy resolution: ~20% ~120 m Cherenkov Light Pool

4 Extragalactic sources Detection of 16 AGNs including 8 discoveries: - 1ES Mrk BL Lac - 1ES PG C 279 (z=0.536) - MAGIC J (3C66A/B) - S (preliminary: PKS at 4.4σ) Other targets: - GRB - Starburst galaxies - Galaxy clusters EXCLUDED Study AGN mechanism Probing EBL spectrum 0.2-2µm STILL ALLOWED constraint from 3C 279

5 S rd MAGIC discovery after an optical ToO with KVA telescope Low-peaked BL Lac Z = 0.31±0.08 Detection on April 2008 Flux>400GeV = 9% crab nebula Photon index = 3.45±0.54 X-ray high flux on April 28th (Swift) April 2008 KVA Swift fermi MAGIC April 2008

6 Multiwavelength campaigns Long term monitoring of bright VHE sources: Mrk 421, Mrk 501, 1ES , 1ES Regular observation of Mrk 421 MWL campaign, ToO Jan 20 th April 30th 2009 SED Correlation with X-ray preliminary

7 Joint HESS-MAGIC-VERITAS campaign of M87 The M87 radio-galaxy Jet Colours: kev (Chandra) Contours: 8 GHz radio (VLA) VHE HST-1 Core Knot D Knot A Shared monitoring between HESS, MAGIC VERITAS X-ray nucleus knot HST-1 Chandra Confirmation of day-scale variability at VHE. nucleus Evidence of correlation with the nucleus in X-ray & Radio. Radio Peak flux Evidence of central origin of the VHE emission (<100Rs to the black hole) jet

8 Galactic sources Detection of 9 objects including 3 discoveries: - LSI IC the Crab pulsar The SNR IC 443 Various kinds of object - SNR - PWN - Binary system - Pulsar - micro-quasar IC 443 MAGIC detection

9 LSI High mass X-ray binary system Discovered by MAGIC in Periodic VHE emission: (26.8 ± 0.2) days Evidence for X-ray / gamma correlation Swift MAGIC

10 Crab Pulsar Special trigger (sum trigger) with threshold = 25GeV First detection of a pulsar above 25 GeV. Flux Compatible wit Fermi result (exponential cutoff) 3.4 σ 6.4 σ Fermi

11 Crab Pulsar MAGIC Follow-up observation: Confirm detection of pulsed emission above 25 GeV. P1/P2 ratio decreasing with energy Updated phasogram: data 7.4σ 4.3σ

12 Dark Matter search DM annihilation or decay can produce VHE gamma rays MAGIC Targets: Galaxy center Nearby Dwarf galaxies Galaxy clusters Unidentified gamma sources (steady sources, hard spectra) Dwarf galaxy Willman-1 No detection. Φ U.L.(E > 100 GeV) ~ g cm -2 s -1 Perseus cluster No detection. Φ U.L.(E > 100 GeV) ~ g cm -2 s -1 Only upper limits can be derived from the MAGIC observations

13 MAGIC phase II MAGIC-2 MAGIC-1 Two 17m telescopes observing in stereoscopic mode Improved drive system: repositioning <20s (both telescopes) Upgraded MAGIC-2 camera: FOV - Higher PMT QE - Larger Trigger area pixels - readout: DRS2-2 GSample/s Stereo Trigger (Level 3) - Energy threshold: ~50 GeV - Rate: ~200Hz

14 Stereo Analysis MAGIC-1 MAGIC-2 Axis crossing M2 δ M1 Image cleaning: - Classical 2 thresholds method with time constraint. Shower direction reconstruction: - Combination of axis crossing and DISP method Energy reconstruction: - Using lookup tables Background rejection: - Based on Random Forest classification major axis DISP centroid Ghost position

15 Performances Energy resolution Zenith angle < 30 Source independent analysis Energy resolution improves strongly at low energy (don t need source dependent analysis)

16 Performances Angular resolution versus Energy DISP+Stereo Axis crossing E>200 GeV Magic phase II M1 alone (DISP) Axis crossing DISP+Stereo Magic phase I The combination axis crossing DISP method solves the problem of parallel images with only 2 telescopes

17 Crab Nebula observation Theta 2 distribution from stereo observation of the Crab hours taken in January Zenith angle < GeV <Energy< 100 GeV Energy> 200 GeV Preliminary Low energy analysis Preliminary Standard analysis

18 Crab Nebula spectrum Albert et al ApJ 674, 1037 Magic phase I Fermi-LAT Abdo, A. A. et al. 2010, ApJ, 708, 1254

19 Crab Nebula spectrum Result with MAGIC phase II (3.5 hours in stereo)

20 Crab Nebula spectrum Smaller error bars in only 3.5 hours

21 Sensitivity x2.5 Integral sensitivity in 50h (5 sigma & >10 events) Preliminary Integral sensitivity reach below 1% crab in 50h performance estimated by MC achieved Analysis still under development (improvement expected)

22 Differential sensitivity Preliminary achieved Best gamma-ray observatory in the range: GeV

23 Mrk 421 Mrk 421 spectrum, 3 hours of data on Jan 14 th 2010 Flux level ~2.5 Crab Spectrum starts at 50 GeV Fitted with power law + exponential cutoff

24 MAGIC Telescopes upgrade Scheduled for Spring/Summer 2011 New MAGIC-1 camera: (clone of Magic-2 camera) pixels - PMT with Higher QE - possibility of using HPD New readout system for both telescopes: - DRS4 running at 2 GSample/s Improved trigger: - Larger trigger area for MAGIC-1 - New sum trigger for both telescopes (threshold= ~25GeV) Easier maintenance with 2 identical telescopes

25 Conclusion MAGIC phase I was a great success thanks to its low energy threshold: - Detection of the farthest VHE source (Z>0.5) - Detection of the first pulsar above 25 GeV MAGIC phase II works in stereo mode for 6 months All performances of the observatory improved. - Energy resolution: 25% ~15% - Energy threshold: 55GeV ~50GeV - Angular resolution: 0.1 < Sensitivity in 50h: 1.6% crab <1% crab MAGIC: Most sensitive instrument at GeV Provide the best overlap with Fermi.