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EUSO-BALLOON DESIGN REVIEW, 18.12.2012, CNES TOULOUSE. Performances of the EUSO-Balloon. Andrea Santangelo IAAT, Eberhard-Karls Univerität Tübingen. - Functional Requirements - Background - Examples of expected Signal Track - An “idea” of angular resolution .
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EUSO-BALLOON DESIGN REVIEW, 18.12.2012, CNES TOULOUSE Performances of the EUSO-Balloon Andrea Santangelo IAAT, Eberhard-KarlsUniverität Tübingen • - Functional Requirements • - Background • - Examples ofexpected Signal Track • - An “idea” of angular resolution
Functional requirements R-4.1-1 Background imaging The Instrument shall image the UV sky background in the bandwidth used by the JEM-EUSO mission observational technique. The background includes star light, airglow, light from artificial sources. Test of the trigger algorithms, switch between observational modes R-4.1-2 Detection of EAS (from the edge of space) The Instrument shall trigger, detect and image EAS with energy above 1018 eV that might develop in the field of view. R-4.1-3 Technology demonstrator All key components and the relative sub-assembly items should be tested according to the configuration foreseen for the JEM-EUSO mission. This is needed to test the JEM-EUSO detection chain. UPDATE: Test capability of the IR-CAM; Test of laser induced EAS. Performances of the EUSO-Balloon
On the night-sky background. Nightglow background: 100 - 500 photons/m2/ns/sr Sakaki, BABY, NIGHTGLOW, Tatiana increases by ~1.5 with clouds Airglow (~100 km height): 250 - 600 photons/m2/ns/sr Moon phases (<25%): <100 ph/m2/ns/sr Background measurements with coarseresolution (~200 km FoV) ph/m2/ns/sr 2000 1000 500 From Tatiana Universitetsky Satellite. aand b = large cities Performances of the EUSO-Balloon
Baby vs. Tatiana and the EUSO-Balloon • The Baby (Balloon) Experiment had a reduced field of view with respect to Tatiana stronger contrast, fluctuations Balloon trajectory O.Catalano et al., NIMA 480 (2002) 547 • EUSO-Balloon: • willhavefinerresolutionatground(~200m) • b) willimplement a control on background variationsto keep a stable trigger rate (~7 Hz) Performances of the EUSO-Balloon
Background simulation • An exampleofbackgroundobservation • 250 photons / m^2 nssr • Uniform distribution • Simulatedatelectronicslevel The EUSO Simulation and Anlaysis Framework has been used for the simulation Performances of the EUSO-Balloon
Testingswitches • The logic of switchesof EUSO-Balloon will be tested to verify: • Capability of protecting the detector from brightevents • Measuretheir light curve and intensity WITH SWITCHES 250 pC Performances of the EUSO-Balloon
The observation principle of JEM-EUSO duration ~ 50 – 150 ms Simulation of the light profile observed at the entrance pupil (above) and throught the instrument using the ESAF code 7 Performances of the EUSO-Balloon
EUSO-BALLOON vs. JEM-EUSO Maximize performance of EUSO-Balloon keepingparametersascloseaspossible to JEM-EUSO Performances of the EUSO-Balloon
Simulations BalloonConfiguration modified „AlcalaConfig“, thatismodified JEM-EUSO • ISS altitude 400 km 40 km • New focalsurfaceparametrization • 3. New pixel angle map • 5. New opticalsystem • 6. Changed FOV: 2*30° 12*12° • 7. Background estimation ~ 50% of JEM-EUSO 9 Performances of the EUSO-Balloon
ExampleShower: 1e19 eV, Theta=20° 10 Performances of the EUSO-Balloon
Example Signal Track • Proton • 1e19 eV • Theta= 20° • Phi= 135° 11 Performances of the EUSO-Balloon
Example Signal Track • Proton • 1e18 eV • Theta= 30° • Phi=120° • Proton • 1e19 eV • Theta= 30° • Phi=120° 12 Performances of the EUSO-Balloon
phe/GTU So called: “Saitama” code Typicaleventobservable by EUSO-Balloon: other code Proton: E = 4·1018eV q = 57.5 f= 188.7 X0 = 9.3 km Y0 = 3.1 km Ypix Xpix Time(GTU) Time(GTU) phe/GTU Ypix Eventlandingoutside the FoV Time(GTU) Xpix 13
Angular Resolution Testingmode: „Debugmode“ a priori knoweldhgeofthetrack Performances of the EUSO-Balloon 14
Trigger Efficiency EUSO-B. & <B>=1.4 phe/pix/GTU EUSO-B. & <B> =2.8 phe/pix/GTU 7 Hz/PDM ● 80 Hz fake trig. o 7 Hz faketrig. Integrated N. Events [1018,E]eV in 10h Trigger efficiency (%) Efficiency=1 & 1.5 x Aug. flux Efficiency=1 & Auger flux EB & A.fl. & <B>=1.4 phe EB & 1.5xA.fl. & <B>=1.4 phe EB & A.fl. & <B> =2.8 phe Energy(eV) Energy(eV) LEFT PLOT: Trigger efficiency curve for events with impact point inside FoV. RIGHT PLOT: Black, red and bluecurvesgivepreliminaryresults on the performance from a 10 h durationflightfor differentassumptions of background and cosmicrayflux. Performances of the EUSO-Balloon
Conclusions • EUSO-Balloowill IMAGE the UV sky background (star light, airglow, TLEs, artificial lights) in the bandwidth used by the JEMEUSO mission observational technique. • All key components and the relative sub-assembly items will be tested according to the configuration foreseen for the JEM-EUSO mission: in particular the trigger scheme and its capability to cope with the variable sky conditions (EXTREMELY IMPORTANT). • Simulationstudieshavebeenperformed: to understand the structure of the expectedsignal and the effectiveenergythreshold of EUSO-Balloon and itspossibility to detectshowers. Resultsconfirm the capability of the instrument of detectingprimarycosmicrays of energy E>1018eV. • Due to the lowcosmicrayflux the detection of a couple of eventswillrequirefewdaysexposuretime thereforethe detection of the first air shower from the edge of the spacewillmostprobablyrequire more thanoneflight. 16 Performances of the EUSO-Balloon