Presentation on theme: "The MAGIC telescope and the GLAST satellite La Palma, Roque de los Muchacos (28.8° latitude - 17.8° longitude, 2225 m asl) INAUGURATION: 10/10/2003 LAT."— Presentation transcript:
The MAGIC telescope and the GLAST satellite La Palma, Roque de los Muchacos (28.8° latitude ° longitude, 2225 m asl) INAUGURATION: 10/10/2003 LAT (mass ~ 3000 kg) GBM (mass ~ 55 kg ) LAUNCH: ~ 2007
THE NEXT GENERATION OF γ- RAY DETECTORS. Ground based and satellite experiments are to some extent complementary for our purpose. –ACT detectors (MAGIC, HESS, VERITAS, CANGAROO): limitate exposure times, an upper energy threshold, a very large effective area, a medium energy resolution, a point-like survey. –Satellite experiments (GLAST): long exposure times, a lower energy threshold, a small effective area, a good energy resolution, a 4 survey.
MAGIC Characteristics Effective area 2,3 · 10 6 cm 2 Energy resolution (σ E /E) ~ 50% (10 GeV) ~ 20% (100 GeV) Angular resolution (σ θ ) ~ 0.05º (transverse) ~ 0.2º (longitudinal) Energy threshold ~ 30 GeV Field of view (sr) 4º Sensitivity 8 · cm –2 s –1 GLAST Characteristics Effective area 10 4 cm 2 Energy resolution (σ E /E) 9% (100 MeV on-axis) <15% ( GeV on-axis) Angular resolution (σ θ ) 3.37º (front), 4.64º (total) (100 MeV on-axis) 0.086º (front), 0.115º (total) (10 GeV on-axis) Energy threshold ~ 20 MeV Field of view (sr) 2.4 Sensitivity ( > 100 MeV) 3 · cm –2 s –1
COMPARISON among gamma telescopes
COMPLEMENTARITY between the two experiments MAGIC a very large collection area GLAST very large field of view high duty cicle wide energy range excellent energy resolution low systematic energy calibration uncertainties (the new imaging Cherenkov telescopes are being built to slew within a few tens of seconds following notification) providing the ground-based observers with alerts for transient sources capability of detecting very short flares from known sources
For individual point sources, MAGIC has unparalleled sensitivity at very high energies, with the ability to resolve shorter-duration flares. For many objects, full multiwavelenght coverage over as wide an energy range as possible will be needed to understand the acceleration and gamma-ray production mechanism. GLAST’ s observations of steady sources at the highest energies will be used to reduce the systematic errors in the sensitivities of the ground – based observatories. At energies above ~10 GeV, the spectra from distant AGNs may be cut off due to absorption by the extragalactic background light. Spectral measurements by both GLAST & MAGIC will be needed to measure these absorptive effects accurately and thus determine the spectrum of the EBL from microwave to optical wavelenghts.
GLAST, with its good energy resolution, is favoured in observing the combined effect of the continuous component and the line; BUT if M χ is higher than GLAST’s threshold MAGIC, owing to its larger effective area, is more adeguate for this purpose. LEP + MSUGRA: M χ > 40 GeV DETECTION PROSPECTS: Dark Matter
On the other hand: GLAST, with its wide angular acceptance, is an ideal instrument to measure eventual local enhancements in the γ- ray flux due to clumps of dark matter. The dependence on the profile which describes the dark matter distribution is in particular critical for detectors like MAGIC which have a small angular acceptance; BUT If a large fraction of the total flux emitted is concentred in a tiny region of the sky, whose coordinates are known with sufficient accuracy, an ACT can be the ideal instrument for detecting neutralino dark matter.
Pulsar POLAR CAP MODELS: ray spectra cutoff very sharply, “superexponential” OUTER GAP MODELS: ray spectra cutoff more slowly, as a simple exponential POLAR CAP MODELS: ray spectra cutoff very sharply, “superexponential” GLAST: energy resolution, dynamic range MAGIC: energy threshold