Building a LIDAR for CTA. What is the new “thing” at IFAE?. Imaging Atmospheric Cherenkov Technique. PHYSICS OF SHOWERS Cosmic rays and gammas impinge the atmosphere Electromagnetic cascades e-e+ pairs bremsstrahlung Cherenkov radiation and Hadronic cascades pions and muons
Building a LIDAR for CTA
~ 10-20 km
Cherenkov light cone
~ 120 m
A short light pulse is emitted to the atmosphere
A portion of the light is scattered back toward the lidar system
The light is collected by a telescope and focused upon a photo detector.
We measure the amount of backscattered light as a function of distance to the LIDAR
Attenuation, when, why?
Multiwire proportional chamber filled with C4H11NO
Big hole in the center
Electronics behind mirror
Can get very complicated!!!