The telescope

1

• The telescope
• MWL campaigns
• Recent results discoveries
• Hints of new physics?

2
Imaging Air Cherenkov Technique
3
The MAGIC site
La Palma, IAC 28 North, 18West
2240 m asl
4

• Currently the largest single-dish Cherenkov
  telescope (17 m diameter)
• In operation since fall 2004 ( starting
  AO-5 in Spring 09)
• Sensitivity 1.6 Crab in 50 h
• Angular resolution 0.1 deg
• Energy resolution 20
• Enhanced duty cycle (by 50) thanks to moonlight
  twilight observations
• Substantially lower energy threshold than other
  installations
• 55 GeV nominal
• 25 GeV pulsar (sum) trigger
• Fast repositioning (30 s)
• 2nd telescope (MAGIC-II) first light this
  winter, ceremony on April 24th

150 physicists, 23 institutes Germany, Italy,
Spain leading
The MAGIC telescope
5
Propagation of g-rays

• For g-rays, relevant background component is
  optical/infrared (EBL)
• different models for EBL minimum density given
  by cosmology/star formation

Science 2008
Measured spectrum affected by attenuation in the
EBL
E-2
Measurement of spectral features permits to
constrain EBL models
6
Attenuation of g-rays
optical depth t
g-ray horizon ?(E,z) 1
Fazio Stecker 1970
7
Extragalactic VHE g-ray sources
24 AGN discovered by IACTs
8
Extragalactic VHE g-ray sources23 blazars 1
radio galaxy

• AGNs sources of extragalactic CRs?
• VHE ?-rays leptonic or hadronic origin?

shape of spectrum

• Extragalactic Background Light
• Propagation mechanisms
• Lorentz Invariance

9
Highlights in MAGIC extragalactic observations
M87 (z0.0043)
PG 1553113 (zgt0.25)
PRELIMINARY
MAGIC discovery
MAGIC discovery
3 more in press
S5 0716 (z0.31)
3C279 (z0.536)
10
Bright Blazars Multiwavelength campaigns

• Simultaneous Multifrequency Observations covering
  
• 15 decades in photon energy
• VHE H.E.S.S., MAGIC, VERITAS
• HE Agile, Fermi
• X-ray Suzaku, Swift, Chandra,
• Integral
• Optical KVA
• Radio Metsahövi,

• Some recent MWL campaigns
• Mrk 421, Mrk 501, PG 1553113, 1ES 1218304, 1H
  1426428, M87
• Further under process, organized

11
1ES 1959650 ApJ 679 (2008) 1029

• MWL campaign during May 2006 with Suzaku and
  Swift
• Two-peaked SED
• VHE emission (Egt200 GeV) at one of the lowest
  ever observed states,
• no significant variability detected
• Modeled by a one-zone SSC model

12
Mrk 421 June 08 flareDonnarumma ApJ 691 (2009)
L13

• Hard X-ray flare triggered MWL campaign
• WEBT, Swift, Agile, MAGIC, VERITAS
• Time variability in TeV and X-ray comparable
• SSC modeling
• Interpretation paper under development

13
PG 1553113
Reimer ApJ 682 (2008) AA 493 (2009)

• Simultaneous MWL campaign during March-April 2008
  with Agile, XTE/ASM and KVA
• paper in preparation

• MWL campaign during July 2006 with H.E.S.S.,
  Suzaku and KVA

Differential spectrum compatible with H.E.S.S.
and previous measurements
Spectral Energy Distributiom homogeneous
one-zone SSC model
14
M87
ApJ Lett. 685 (2008) L23
The first non-blazar radio galaxy observed to
emit VHE g-rays

• VERITAS/MAGIC/H.E.S.S. monitoring
• 8s on 2008 Feb 1 ? Trigger issued to VERITAS
  and H.E.S.S.
• 9.9s in overall sample (22.8 hours) between 2008
  Jan 30-Feb 11
• Flux variable between 3-15 Crab
• High variability gt 350 GeV
• Confirming day-scale variability (5.6s). No
  intra-night variability
• Compatible with constant between 150-350 GeV

15
Optical triggers ? new discoveries
KVA optical telescope at la Palma
ApJ, 648 (2006) L105
Mkn 180 z 0.045
March 2006
MAGIC 12.1 h S5.5 s
ApJ, 667 (2007) L21
March-May 07
1ES 1011496 z 0.212
MAGIC 18.7h S6.2 s
S5 0716714 z 0.31
S5 0716714MAGIC PRELIMINARY
Significance 6.8 s
16
The 3C 66A/B region
ApJ Lett. 692 (2009) 29

• B radio Galaxy
• A distant Blazar, VHE candidate (EGRET,
  Crimea, VERITAS, Fermi)
• MAGIC observations triggered by optical outburst
  in 2007

3C 66B is more likely the source of emission
(MAGIC J0223430)
17
3C279 the most distant
Science 320 (2008) 1752
skymap

• flat-spectrum radio-quasar at z0.536
• brightest EGRET source. Highly variable, fast
  variability (6 hours)
• MAGIC observed it in 2006 during WEBT campaign
  for 9.7 hours in 10 nights
• Clear detection 23rd Feb 2006 (6.2s)
• First FSRQ in TeV g-rays
• Major jump in redshift

18
Energy spectrum of 3C279
Measured and EBL-corrected spectrum
19
3C279 and the g-ray horizon
Test of the transparency of the universe extended
to z 0.536!
20
(No Transcript)
21
Spectral characteristics of observed AGN
observed spectral index

• Selection bias?
• New physics?

adapted from De Angelis, Mansutti, Persic,
Roncadelli MNRAS 2009
redshift
22
Limits on 3C454.3

• We have also searched farther out
• during summer 2007 intense emission of 3C454.3 -
  a well known FSRQ _at_ z 0.86 - detected by AGILE
• Upper limits derived from
• MAGIC data together
• with nearly simultaneous
• multifrequency data
• allow to constrain the SED

23
ApJ 669 (2007) 892 Phys Lett B 668 (2008) 253
Flares a way to new physics?
Energy-delayed flare of Mrk501

• Quantification of the delay
• (0.0300.012) s/GeV
• Probability of no delay 2.6
• Possible explanations
• Astrophysical intrinsic source effects
• photons at different energies were
• emitted simultaneously
• Propagation effect due to Lorentz invariance
  violation
• ? Probing the Planck energy scale

IF
Opens the way to future population AGN studies at
different z
24
CONCLUSIONS

• MAGIC is producing high quality astrophysics
  after 3.5 observation cycles
• Lowest energy threshold gt deepest horizon
• We have discovered 8 new extragalactic sources,
  detected and studied 5 known
• Important contributions to the understanding of
  AGN, EBL
• Now reaching out much further in redshift high
  energy photons (often traveling through large
  distances) are a powerful probe of fundamental
  physics under extreme conditions
• MAGIC-II starts operations on April 24th

25
BACKUP
26
Optical depth