The MAGIC Telescope System Scientific Highlights, Status and Future Perspectives

Sabrina Einecke for the MAGIC Collaboration

27th Rencontres de Blois 31th May – 5th June 2015 Canary Island of La Palma The MAGIC Telescopes

Observatorio del Roque de los Muchachos

2200 m above sea level

§ Stereoscopic system of two IACTs

§ 17 m diameter mirror dish

§ Energy regime: ~50 GeV – 50 TeV

Sabrina Einecke The MAGIC Telescope System: 27th Rencontres de Blois 2 for the MAGIC Collaboration Scientific Highlights, Status and Future Perspectives 31th May - 5th June 2015 The MAGIC Collaboration

~190 collaborating physicists from 10 countries

Bulgaria Inst. For Nucl. Research Sofia Croatia Consortium Finland Consortium Germany TU Dortmund, MPI Munich, U. Würzburg, DESY Zeuthen India SINP Kolkata Italy U. Udine & INFN Trieste, U. & INFN Padova, INAF Roma, U. Siena & INFN Pisa & U. Pisa, U. Insubria & INFN Milano Japan Consortium Poland U. Łódź Spain U. Barcelona, UAB Barcelona, IFAE Barcelona, IEEC-CSIC Barcelona, U. Complutense Madrid, CIEMAT Madrid, IAC Tenerife Switzerland ETH Zurich

Sabrina Einecke The MAGIC Telescope System: 27th Rencontres de Blois 3 for the MAGIC Collaboration Scientific Highlights, Status and Future Perspectives 31th May - 5th June 2015 Aleksić et al. (MAGIC Collab) Major hardware upgrades in 2011/12 Astropart. Phys. (2015) arXiv:1409.6073

Hardware changes Uniform § New MAGIC-I camera stereoscopic system § Increased trigger area of MAGIC-I Better low § New readout system (DRS4 and energy programmable receiver boards) performance

Better flux sensitivity for extended sources

Better angular Another innovation: Online analysis client resolution § Analysis results during observations § Possibility to extend observations § Possibility to alert other MWL partners Reduction à Sensitive to 10% Crab flux in 30 minutes of downtime

Sabrina Einecke The MAGIC Telescope System: 27th Rencontres de Blois 4 for the MAGIC Collaboration Scientific Highlights, Status and Future Perspectives 31th May - 5th June 2015 Aleksić et al. (MAGIC Collab) Major hardware upgrades in 2011/12 Astropart. Phys. (2015) arXiv:1409.5594

§ Improved performance (especially below 100 GeV) à Reduction of needed observation time by factor 2.5

§ Angular resolution: improved by ~ 5-10%

§ Trigger collection area: enlarged by ~ 30%

§ Off-axis performance: improved by ~ 25% (at ~ 1° offset)

§ Systematics: lowered by factor 2 Even better performance since mirror exchange last summer!

Sabrina Einecke The MAGIC Telescope System: 27th Rencontres de Blois 5 for the MAGIC Collaboration Scientific Highlights, Status and Future Perspectives 31th May - 5th June 2015 Current Status

§ Energy range: 50 GeV to 50 TeV

§ Sensitivity (5σ in 50 h): 0.066% Crab Nebula flux (above 220 GeV) § Energy resolution: 16% at moderate energies

§ Angular resolution: < 0.07° above 250 GeV

§ Fast repositioning (~25 s for 180° azimuth rotation)

Unprecedented sensitivity after upgrade: à since then 8 new VHE sources discovered by MAGIC à among them 3C 58, the least luminous PWN so far detected in VHE

Discoveries after upgrade: PKS 1441+25 (ATel #7416) S4 0954+65 (ATel #7080) S3 0218+35 (ATel #6349) 3C 58 (A&A 567 8) RX J1136.5+6737 (ATel #6062) RBS 0723 (ATel #5768) MS 1221.8+2452 (ATel #5038) H 1722+119 (ATel #5080)

Sabrina Einecke The MAGIC Telescope System: 27th Rencontres de Blois 6 for the MAGIC Collaboration Scientific Highlights, Status and Future Perspectives 31th May - 5th June 2015 MAGIC: Physics Program

Extragalactic Science Astroparticle & Fundamental Physics § Active Galactic Nuclei § Dark matter searches § Gamma-ray bursts § Cosmic rays § Study of Extragalactic § Diffuse gamma-rays Background Light § Galaxy clusters [NASA] § ... § ... [NASA]

Galactic Science § Pulsars § Supernova remnants

§ ... [NASA] [NASA]

§ Testing models of gamma-ray emission § Study of spectral energy distributions § Study of variabilities § Hunting new sources

Sabrina Einecke The MAGIC Telescope System: 27th Rencontres de Blois 7 for the MAGIC Collaboration Scientific Highlights, Status and Future Perspectives 31th May - 5th June 2015 Extragalactic VHE gamma-ray sources

MAGIC discovery: PKS 1441+25 z = 0.939

MAGIC discovery: S3 0218+35 z = 0.944

Sabrina Einecke The MAGIC Telescope System: 27th Rencontres de Blois 8 for the MAGIC Collaboration Scientific Highlights, Status and Future Perspectives 31th May - 5th June 2015 Probing the Extragalactic Background Light

§ Emitted flux of the source is attenuated by extragalactic background light

Φ (E,z) = Φ (E) × e-τ(E,z) measured emitted τ(E,z): optical depth

[Dwek et al.]

à VHE gamma-ray sources with different redshifts needed

Sabrina Einecke The MAGIC Telescope System: 27th Rencontres de Blois 9 for the MAGIC Collaboration Scientific Highlights, Status and Future Perspectives 31th May - 5th June 2015 ATel #6349 S3 0218+357 MAGIC discovery

§ Detection of the most distant VHE emitting blazar: z = 0.944 § Detection of the first gravitationally lensed VHE emission

Gravitational lense B0218+357 Blazar S3 0218+357

Time delay z=0.944 z=0.684 [NASA]

Radio survey (JVAS) Fermi-LAT obs. in 2012 Time delay: (10.5 ± 0.4) days Time delay: (11.46 ± 0.16) days [Biggs et al. 1999] [Cheung et al. 2014]

Sabrina Einecke The MAGIC Telescope System: 27th Rencontres de Blois 10 for the MAGIC Collaboration Scientific Highlights, Status and Future Perspectives 31th May - 5th June 2015 ATel #6349 S3 0218+357 MAGIC discovery

Fermi-LAT public data § Fermi-LAT July 2014: Gamma-ray flare with unusually hard spectrum (Buson et al, ATel #6316)

§ No MAGIC observation during original flare (full moon) à ~10 days later: delayed emission MAGIC arrived at scheduled time preliminary

§ Signal with > 5σ in 4 consecutive nights, point-like source full moon

Sabrina Einecke The MAGIC Telescope System: 27th Rencontres de Blois 11 for the MAGIC Collaboration Scientific Highlights, Status and Future Perspectives 31th May - 5th June 2015 Aleksić et al. (MAGIC Collab) IC 310 Science 346 (2014) 1080-1084

§ Blazar or radio galaxy? Perseus cluster à Kiloparsec-scale radio structure à Rapid variability (gamma- and X-rays) à Intrinsic luminosity 2-3 orders of magnitude below the one of typical blazars

§ November 2012: à Extraordinary flare à Hard (~1.8 intrinsic) spectrum

à Spectrum extends up to ~ 8 TeV without any sign of cut-off à Rapid variability

Sabrina Einecke The MAGIC Telescope System: 27th Rencontres de Blois 12 for the MAGIC Collaboration Scientific Highlights, Status and Future Perspectives 31th May - 5th June 2015 Aleksić et al. (MAGIC Collab) IC 310 Science 346 (2014) 1080-1084

§ Rapid variability during flare in Nov. 2012

à Doubling time scale < 4.8 min corresponds to ~ 20% of 5 C.U. event horizon light-crossing time à Sub-horizon scale variability Flux doubling

time scale < 4.8 min § Challenges shock-in-jet models à Emission is too fast 1 C.U. à Synchrotron radiation would absorb TeV emission

§ Explanation by pulsar-like magnetosphere model + - à e e accelerated in electric field in vacuum gap region à Hard gamma-ray spectrum from electromagnetic cascading à Variability as gap varies with plasma turbulence and accretion rate

Sabrina Einecke The MAGIC Telescope System: 27th Rencontres de Blois 13 for the MAGIC Collaboration Scientific Highlights, Status and Future Perspectives 31th May - 5th June 2015 Aleksić et al. (MAGIC Collab) Crab Nebula JHEAp (2015) arXiv:1406.6892

§ Spectrum with high precision: 50 GeV - 30 TeV, 5 bins per decade

69h, 2009-2011

§ Daily light curve: no hint of flux variabilities

§ MAGIC / Fermi-LAT fit: à Good overlap

à IC peak at (53 ± 3) GeV ß 3 decades à à Bad fit quality of log-parabola à Emission models currently revisited

Sabrina Einecke The MAGIC Telescope System: 27th Rencontres de Blois 14 for the MAGIC Collaboration Scientific Highlights, Status and Future Perspectives 31th May - 5th June 2015 Aleksić et al. (MAGIC Collab) Crab Pulsar A&A 565 (2014) 12

§ Discovery of bridge emission above 50GeV à 6.2σ in 135h

§ Challenges current pulsar models à Pulsed VHE emission favors emission sites in outer part of magnetosphere à Data to test new theories

bridge emission § TeV pulsed emission above 400 GeV P1: 8σ P2: 12.6σ à Energy spectrum extends up to ~2 TeV with no evidence of cut-off à Findings favor TeV gamma-ray production via Inverse Compton scattering close to or beyond light cylinder + - radius by either secondary e e or electrons in wind

Sabrina Einecke The MAGIC Telescope System: 27th Rencontres de Blois 15 for the MAGIC Collaboration Scientific Highlights, Status and Future Perspectives 31th May - 5th June 2015 Summary & Future Perspectives

§ Improved overall performance § Observation of valuable scientific results: § 2 most distant VHE gamma-ray sources § First gravitational lense in VHE gamma-rays § Sub-horizon scale variability § TeV pulsed emission § Bridge emission § Least luminous pulsar wind nebula à Much exciting data with large scientific impact!

§ SUM-trigger-II installed à Will lower stereo trigger threshold § Topological trigger installed à Includes topological information of shower in both camera à Will lower energy threshold à Will enlarge collection area at lowest energies

Sabrina Einecke The MAGIC Telescope System: 27th Rencontres de Blois 16 for the MAGIC Collaboration Scientific Highlights, Status and Future Perspectives 31th May - 5th June 2015