Marcos López for the MAGIC Collaboration Univ. Complutense Madrid, Spain, marcos@gae.ucm.es ICRC 2017 – Busan
The MAGIC telescopes La Palma island Characteristics • 2 Imaging Atmospheric Cherenkov Telescopes • 17 m diameter with active mirror control • Fast readout ∼ 2 GS/s • ∼ 2TB per night Performance • Energy range: 50 GeV to 50 TeV MAGIC site • Sensitivity: 10% Crab in 1 h above 100 GeV • Energy resolution: 15 – 23% • Angular resolution: ∼ 0.1º MAGIC continuous improvement • 4x improvement sensitivity over last decade • 10x at the lowest energies ! 2
MAGIC Galactic Physics Program MAGIC has made significant contributions to the study of galactic sources Pulsars PWN Discovery of the first VHE pulsar Crab nebula over 4 decades Fundamental Physics SNRs Mapping de Galactic Center Study of LIV Bianry systems Search for Pevatrons Search for Microqusars Periodic emission from binary systems 3
Pulsars at TeVs Pulsars Where do 𝜹 -rays come from? Before MAGIC MAGIC • Different 𝜹 -ray emission sites • 2008: Crab pulsar above 25 GeV • Rule out low altitude models proposed for Crab: • 2012: Spectrum measured up to 400 GeV • Spectra follow power-laws ➔ No cutoff seen New models proposed • Within or beyond the magnetosphere • If beyond, expected cutoff at ~0.5 TeV • Emission via curvature radiation • Expected sharp exp. cut-offs at few GeV 4
Pulsars at TeVs Pulsars Up to which energy does the Crab pulsate? MAGIC E > 400 GeV MAGIC latest Crab results 150 • MAGIC detected TeV emission from Crab E > 400 GeV 100 • Used 8 years of data, 320 hours 50 • Spectra of both peaks extending as power- 0 -50 laws far beyond the expected cutoffs: 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 Phase • ] P1 detected up to 0.6 TeV ( 𝛥 =3.5 ± 0.1 ) -1 s -2 -10 10 [TeV cm • P2 detected up to 1.5 TeV ( 𝛥 =3.0 ± 0.1) -11 10 dEdAdt dN Implications of TeV emission -12 10 2 E • Synchrotron-curvature ruled out -13 10 Fermi-LAT P1 Fermi-LAT P2 ➔ Most likely, emission from outer -14 10 MAGIC P1 MAGIC P2 magnetosphere via IC -15 10 -1 2 3 10 1 10 10 10 Energy [GeV] • But no model can fully explain TeV Ansoldi et al., A&A 582 A133 (2016) pulsations 5
Cas A is not a Pevatron ! SNRs Context • SNRs considered the most promising source of CRs up to the “Knee”. • But no evidence (yet) of particle acceleration up to 10 15 eV Cassiopeia A (Cas A) • Bright and point-like in GeV/TeV ( HEGRA, VERITAS, MAGIC and Fermi) • Considered a classical Pevatron candidate arXiv: 1707.01583 / D. Guberman ICRC2017 MAGIC latest results • 160 h of data (2014 and 2016) • SED measured up to 8 TeV • Exponential cut-off (EPWL) fit preferred over pure power-law (PWL) at 4.6 𝝉 • Cut-off at ~ 3.5 TeV • Even if TeV due solely to hadrons, Cas A cannot be a PeVatron at present time 6
Binaries Super - orbital Variability of LSI +61 303 Context A&A 591, A76 (2016) / D. Hadash, ICRC 2017 • Binary system: Be star + unknown compact object (orbital period 26.5 days) • Discovered at VHE by MAGIC in 2006 • Orbital variability: TeV emission only when compact object is far from the stellar disc • Modulation at longer time scales? Latest results • Extended campaign by MAGIC & VERITAS in 2010-14, added to archive data since 2006 • Superorbital 4.5 yr variability found at TeV ! • Period consistent with optical, radio and HE Possible superorbital explanation Flip-flop magnetar scenario (Torres et al. 2012): Expected antcorrelation between Size of the disk and VHE emission 7
Binaries Galactic jets at TeV ? • Acceleration in microqusars jets may produce TeV, but not (yet) detected • MAGIC has deeply studied 2 high-mass microquasars: Cygnus X-1 and X-3 Cygnus X-3 Cygnus X-1 • Detected in 2009 by Fermi during a flare • A recent analysis of ~8 yrs of Fermi-LAT • In 2016, flaring in radio and GeV shows detection up to 20 GeV • MAGIC follow-up observations for 70 hr • MAGIC observed 100 h during 2007-2014 ➔ No detection at TeV ➔ No detection above 200 GeV MAGIC Coll., submitted to MNRAS (2017) VHE flux is suppressed ➔ no efficient acceleration on the jets See also A. Fernández-Barral @ ICRC 2017 8
Galactic Center • In 2012 found a gas cloud (~3 Earth masses) orbiting towards the SMBH Sgr A* • MAGIC observed 70 h (2012-15) the GC Light curve ESO simulation Gas Cloud • No TeV variability found during the passage of the gas cloud Sgr A* 2013 2014 2015 Flux > 1 TeV 10x Flux > 10 TeV Ahnen et al., A&A, 601 (2017) A33 9
Galactic Center • In 2012 found a gas cloud (~3 Earth masses) orbiting towards the SMBH Sgr A* • MAGIC observed 70 h (2012-15) the GC Light curve ] -1 Ahnen et al., A&A, 601 (2017) A33 s -2 [TeV cm • No TeV variability found during the − 10 10 passage of the gas cloud dE dA dt dN − 11 10 2 E Syst. err. MAGIC − 12 10 Spectrum of Sgr A*: 0.3 - 50 TeV Fermi, Malyshev et al. 2015 MAGIC, this work 0.1 deg (Schmelling) MAGIC, this work 0.1 deg (Forward) • Power-law with an exp. cutoff at 7.6 TeV Had. model, Chernyakova et al. 2011 Had. model, Ballantyne et al. 2011 − 13 10 Had. model, Linden et al. 2012 Had. model, Fatuzzo et al. 2012 Hybrid model, Guo et al. 2012 • Matches nicely Fermi spectrum Lept. model, Kusunose et al. 2012 − 14 10 − − 2 1 2 3 4 5 10 10 1 10 10 10 10 10 • Compatible with leptonic or hadronic models E [GeV] SgrA* & G0.9 removed G0.9 G0.9 Morphology • Detected Sgr A* and G0.9+ 0.1 Arc Arc • Removing foreground ➔ Discovered new Sgr A* Sgr A* VHE source in the radio Arc region: MAGIC J1746.4-2853 10
Follow - up of HAWC sources Unidentified HAWC sources • The 2 nd HAWC catalogue (2017) contains 39 detected TeV sources. • 19 of them have no association with any known VHE source MAGIC archive data • Some of these 19 Unid. sources were in the FoV (<1.5º) of former MAGIC observations: HAWC source Tobs [h] 2HWC J2006+341 61 2HWC J1907+084 4 2HWC J1852+013 120 Preliminary • Re-analysis of these MAGIC observations looking for point-like emission (0.10º) or slightly extended (0.16º) ➔ No signal found 11
MAGIC opening to external scientists https://magic.mpp.mpg.de/outsiders/magicop/ • Starting from this year, external scientists can apply for MAGIC observation time • Deadline for the call: 03-Nov-2017 MAGIC welcomes observational proposals by external scientists: Looking forward to do great science together ! 12
Summary Outstanding recent MAGIC galactic results: • Crab pulsation up to TeV • Cas A is not a Pevatron • Superorbital TeV modulation in LS I+61 • Deep observations of microquasars ➔ No detections so far • 4 year observations of Galactic Center ➔ Detection of a source in the Arc region • Follow-up studies of Unid. HAWC sources ➔ No counterpart found For more details, see the 7 dedicated MAGIC galactic contributions @ ICRC 2017: • A. Fernández-Barral: Pulsar Wind Nebulae • D. Guberman: Cassiopeia A • D. Hadash: Binary Systems • A. Fernández-Barral: Cygnus X-1 & Cygnus X-3 • M. Strzys: Gamma-Cygni • M. López: Black Widow B1957+20 binary system • M. Gaug: Lorentz invariance violations using the Crab pulsar 13
BACKUP 14
Pulsar searches Pulsars Geminga Black widow B1957+20 ms pulsar • After Crab, it is the brighter Fermi • MS pulsars orbiting low massive stars pulsar in the Northern Sky could produce VHE emission • VHE emission tail? • But not (yet) detected • MAGIC observed the system for 66 h • Observed by MAGIC for 60 h • • 4 possible regions in which 𝜹 -rays could be No signal detected above 50 GeV. produced • Upper limits don’t allow to rule out the existence of a VHE power-law tail. Region Expected emission I. Bow shock Extended / steady MAGIC Geminga II. Inner nebula Point-like / steady III. Binary system Point-like / modulated IV. Pulsar Point-like / pulsed • P2 No emission detected in any case PSR B1957+20:P2 PSR B1957+20:P2 460 ] Events -1 MAGIC UL MAGIC UL MAGIC UL s -10 10 -2 MAGIC > 50 GeV dN/dE [TeV cm FERMI FERMI FERMI P2 440 PLExpCutoff: PLExpCutoff: PLExpCutoff: Γ Γ Γ =1.45 Ec=1.8 b=1.0 =1.45 Ec=1.8 b=1.0 =1.45 Ec=1.8 b=1.0 PL: PL: PL: Γ Γ Γ =2.23 =2.23 =2.23 -11 10 420 2 E -12 10 400 -13 380 10 360 -14 10 Ahnen et al., A&A 591 A138 (2016) 340 -15 10 -1 2 3 10 1 10 10 10 -0.2 -0.1 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 Pulsar phase Energy [GeV] Ahnen et al., arXiv:1706.01378 15
Pulsar Wind Nebulae searches PWN • PWNe are the most numerous population of TeV sources in our galaxy: • Powered by young and energetic pulsars ➔ Particles accelerated to VHE in the pulsar surroundings, or at the shocks • MAGIC detected the less luminous (3C 58) and the most luminous ones (Crab) A. Fernández-Barral , ICRC 2017 Latest MAGIC observations • MAGIC has observed 3 promising PWN candidates around high spin-down power Fermi pulsars Pulsar Campaign Tobs [h] 37 PSR J0631+1036 2015/16, 2016/17 PSR J1954+2838 2015 16 4 PSR J1958+2845 2015 • No signal found from any candidate. • MAGIC results are in agreement with the expected luminosity in the 1-10 TeV band. The band shows the fit obtained from detected PWNe and ULs in HESS galactic survey 16
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