Working Group II: Increase the Sensitivity of MAGIC A GENERAL - PDF document

Working Group II: Increase the Sensitivity of MAGIC A GENERAL EXPERIENCE IN GROUND-BASED GAMMA ASTRONOMY: TYPICALLY AFTER FOUR YEARS THE DETECTORS BECOME PARTLY OBSOLETE AND NEED A MAYOR UPGRADE MAGIC I HAS NOW WORKED FOR 4 YEARS ->TIME TO IMPROVE We have currently a sensitivity of 1.6 % of the CRAB Flux (5 � in 50 hours) We have currently a trigger threshold of 50-60 GeV (L1 Trigger logic) in Zenith position Our software threshold is much higher, see our papers THE UNCHARTED TERRITORY FOR MAGIC IS BELOW 150 GEV THERE ARE QUITE MANY SOURCES EXPECTED IN THE ENERGY RANGE BETWEEN 50 AND 150 GEV ALREADY MANY OF OUR RECENTLY OBSERVED SOURCES SHOW VERY STEEP SPECTRA-> WE NEED TO OBSERVE BELOW 100 GEV 10 X MORE LBLs THAN HBLs PULSARS WITH UPPER CUTOFFS EXTENDING ABOVE 50 GEV GRBs: ONE OF THE INITIAL GOALS OF MAGIC CHALLENGE TO OBSERVE HIGH REDSHIFT AGNS - THE EBL CHALLENGE TO MAKE GOOD SPECTRAL MEASUREMENTS YOU NEED TO OBSERVE OVER QUITE SOME ENERGY RANGE • UHU II ( U NDER HU NDRED GEV EVENT ANALYSIS) •WE HAD UHU I TO IMPROVE OUR SENSITIVITY BELOW 100 GEV BUT IT BASICALLY FAILED LET’S MAKE A CRITICAL REVIEW WHERE WE FAILED •HARDWARE IMPROVEMENTS IN SENSITIVITY •ANALYSIS IMPROVEMENTS IN SENSITIVITY •LET US DEFINE THE INCREASE IN SENSITIVITY IN A DOUBLE SENSE •A) increase the detection efficiency in a given energy range •B) lower the threshold of our analysis

POSSIBLE HARDWARE IMPROVEMENTS 1. IMPROVE THE TRIGGER: SUM TRIGGER, IMPROVED SUM TRIGGER? LARGER AREA, MORE UNIFORMITY, BETTER COMPUTER CONTROL HAMLET: PUT MORE MONEY IN THE COMPUTING TO HANDLE HIGHER TRIGGER RATES STABLE CALIBRATION UNITS, LIGHT PULSER… • STARGUIDER CAMERA. FULL IMPLEMENTATION (REFERS ALSO TO AMC) • IMPROVED DUSK,DAWN OPERATION (MOON OPERATION) • IMPROVED GRB OPERATION • MINIMIZE BACKLASH LOSSES (PARTICULARLY IN CULMINATION AND • WOBBLE MODE IMPROVED CAMERA UNIFORMITY Example of backlash problem Before culmination: declination motor PUSHES -> compression of motor mount mechanics Lc After culmination: declination motor pulls -> max length of motor mount mechanics Lp (>Lc - > motor runs, but telescope does not move) Note: compression, extension also sideways, but difficult to estimate Note : compression length can vary

ANALYSIS IMPROVEMENTS 1. IMPROVE LARGE SIZE EVENT SELECTION. LEAKAGE CUT MODIFICATION... 2. OPTIMIZE BETTER THE g/h SEPARATION FOR LOW SIZE EVENTS • USE NOT ONLY ONE CUT FOR ALL IMAGE PARAMETERS • e.g., use different tail cuts for ALPHA calculation • weights for W., L, .... (second look) • new optimization procedures • can we profit more on timing: see Dorota’s paper • rain analysis (within the relevant image (far rain, next ring(s) around events) • …. • Implementation of stereo observations HOW TO PROCEED A) COLLECTION OF IDEAS, BRAINSTRORMING B) EVALUATE IDEAS, FEASIBILITY,COSTS, EXPECTED GAIN C) WRITE IT UP AND PRESENT A SUMMARY TO THE MAGIC COLLABORATION D) SIGN UP FOR A SUBJECT