Observations of the AGN 1ES1959 650 with the MAGIC telescope

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Observations of the AGN 1ES1959650 with the
MAGIC telescope
Nadia Tonello and David Paneque
for the MAGIC collaboration
Max-Planck-Insitut für Physik, München

• The MAGIC Telescope
• 1ES1959650
• Results from the observations
• Conclusion

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The MAGIC Telescope
Largest Imaging Air Cherenkov Telescope for
?-ray astronomy 236 m2 mirror dish 576 high-QE
PMTs fast repositioning tRlt30 s

• Canary Island La Palma
• 2200 m asl

MAGIC aims to cover the energy range 30 GeV - 30
TeV
Regular observations started in September 2004
Status report, Mirzoyan et al., this conference
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About 1ES1959650

• 1998 First ? detection Utah Seven Telescope
  Array
• (Nishiyama et al, 1999)
• Confirmed in 2002 by WHIPPLE and HEGRA
• (Holder et al, 2003)
• (Aharonian et al, 2003)

Elliptical galaxy Active Galactic Nucleus
(Blazar type) z 0.047 RA
19h5959.8 Dec 65?08'54'' Observability from
La Palma May-October 35?-54? z.a.
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About 1ES1959650

• 1 - TeV-emission in quiescent state is very low
• HEGRA System (2000-2001)
• gt 100 h obs. time (Eth gt 2TeV) 5.2 ? ,
  average integral flux 5.3 Crab
• (Aharonian et al, AA 406, 2003)

2 - Orphan flare in TeV-rays in June 2002
(High activity in ?-rays with low activity in
X-rays) Leptonic or hadronic acceleration ??
Hint for neutrino excess recently reported
by AMANDA (Paris, 2005) Correlation with
position of a UHECR from HiRes (astro-ph/0406654)

3 - Intermediate distance TeV blazar
Candidate to disentangle source features from
absorption in EBL
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Observation with MAGIC
Analysis used was optimized on the Crab Nebula
data set, which was obtained during the same
period and zenith angle range
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ALPHA PLOT
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X-ray light curve

• Low state in X-Ray

5 - 7 Sept
7 -17 Oct
RXTE mission day
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Optical light curve

• Low state in optical

Tuorla Observatory Blazar Monitoring
Program (http//users.utu.fi/kani/1m/jytable.html)
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Gamma-ray light curve

• No significant variation of ?-ray activity

Average integrated photon flux (above 300 GeV)
15 Crab
1ES1959 detected in quiescent state
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Preliminary spectrum
Spectrum softer than that of Crab
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Preliminary spectrum
Peak of Inverse Compton NOT seen down to 200 GeV
? 2.9 0.2
? 3.2 0.2
Only statistical errors
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Conclusions

• Clear signal (8 ?) from 1ES1959650 in quiescent
  state with MAGIC in 7 h. obs.
• Integrated flux 15 Crab (gt 300 GeV)
• Differential energy spectrum with ? 2.9 0.2
• Inverse Compton emission peak not seen
  down to 200 GeV (PRELIMINARY). Work ongoing.
• Performance of the new IACT instruments allow to
  do VHE ?-astronomy of blazars in quiescent state

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Imaging Air Cherenkov Telescopes
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Preliminary analysis

• Random Forest
• MC ? noise tuned to september off data sample.
• Hadrons randomly chosen from real on data (25 k
  events).
• Parameters Width, Length, Size, Dist, Conc,
• logLength(logSize), logWidth(logSize), M3Long
• Cut in MHadronness
• chosen from Crab
• Maximum significance had 0.1
• Maximum excess events had 0.5
• Cuts applied to 1ES1959 without any further
  optimization.

Significance
Excess events
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(No Transcript)
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(Aharonian et al, AA 406, 2003)
Fig. 3