Approved by ESA for the “Phase A study” on the International Space Station

1. EUSO E U S O xtreme niverse pace bservatory 3rd General Meeting - Toward the End of Phase A Simulation Subsystem Vincent Van Gogh, “The starry night” An Innovative Space Mission doing Astronomy by looking downward from the Space Station at the Earth Atmosphere Approved by ESA for the “Phase A study” on the International Space Station Giacomo D’Alì Staiti, Huntsville, May21, 2003 EUSO: Extreme Universe Space Observatory

2. EUSO EUSO : Extreme Universe Space Observatory Giacomo D’Alì Staiti, Tokyo, November 8, 2002 Simulation – Phase A Work Plans • Physics process•UNISIM Hybrid method: Cerenkov generation refinement DONEHadron showering improvement (see S. Bottai, this meeting) •GL/SLAST Analytical method: Cerenkov generation addition DONE•CORSIKA Montecarlo (interface with ESAF) TO BE DONE • Fluorescence generation:• Updated with new measurements DONE • Atmosphere modelling: • Use of standard Transport equations DONE • Interface with realistic databases, atmosphere sounding dataSTARTED • Detector simulation:• final design implementationAVAILABLE• Simulated data production for reconstruction software processing:Order of 104 proton events pre-released by the end of JuneDONE • 2×104 events (see S.Bottai, this meeting) ready to be proceesed • General Simulation Software (ESAF Euso Simulation and Analysis Framework):• 1st release of a complete and documented version of theROOT-based software expected by the end of Phase A.RELEASED /UNDER TEST

3. EUSO Event Reconstruction Event Type (EECR, EEn, Meteor,…) Direction Reconstruction Energy Reconstruction Particle identification EUSO : Extreme Universe Space Observatory Giacomo D’Alì Staiti, Huntsville, May 21, 2003 Physics Process Simulation Housekeeping, atmosphere sounding and calibration data • Event generators: • fast generator, bulk event generator, 2nd order effect simulation • EECRs, EEn, Meteors, Lightning) Physics Event Analysis Active target Simulation Event by event Correction factors Fluorescence yield Cerenkov light production Atmosphere description Absorption and Transmission Pressure, temperature, Clouds effect Detector Simulation Geometry description Optics description Focal surface description Electronics description Trigger simulatiom Simulated Raw-like data Real Raw Data

4. EUSO EUSO : Extreme Universe Space Observatory Giacomo D’Alì Staiti, Huntsville, May 21, 2003 END-to-END Simulation • From the physics process to the expected experimental performances: • Do we agree on the same baseline for the “ingredients” to be used? • EECR Input (GL, SLAST, UNISIM, CORSIKA, AIRES) proton primary shower heavy primary shower neutrino induced shower • Fluorescence Yield: ei(li,p,T;H?) = rAi/(1+rBiT) Ai, Bi taken by Nagano et al. …more by at this meeting Atmospheric Transport equation: LOWTRAN7 code, different atmosphere profiles Rayleigh, Mie scattering, O3 abs., f(l) Čerenkov back scattering and diffusion Simple clouds treatment    N(x;E0,A, xmax,t) lateral distribution (NKG) Čerenkov light generation full ESAF implementation is agreed and used by everybody ? full ESAF implementation plans from support activities? energy (<m.i.p.) dependence humidity dependence   is agreed and used by everybody ?  full ESAF implementation  plans to insert LIDAR info’s? • deconvolution problem, … more at this meeting     

5. EUSO EUSO : Extreme Universe Space Observatory Giacomo D’Alì Staiti, Huntsville, May 21, 2003 END-to-END Simulation From the physics process to the expected experimental performances:Do we agree on the same baseline for the “ingredients” to be used? Detector simulation Optical system Focal surface & PMT Front End Electronics Trigger Background generation Nightglow diffused background Overall Detector Performances (Triggered events) Aperture (energy function) Acceptance (angle, position & energy) Duty cycle Raw-like Data to Reconstruction (SDA) Data with parameterised detector (AW, SLAST, UNISIM) ESAF Data (July 2002, prerelease, May 2003 2×104 ev.) The ESAF core: ready for ESAF implementation full ESAF implementation full ESAF implementation full ESAF implememntation  in ESAF at FS pixel level  march data processed outside ESAF (E. Plagnol, this meeting)

6. EUSO EUSO : Extreme Universe Space Observatory Giacomo D’Alì Staiti, Huntsville, May 21, 2003 END-to-END Simulation From the physics process to the expected experimental performances Do we agree on the same baseline for the “ingredients” to be used? Event Reconstruction The topic will be addressed in the Data Analysis Section today Experimental performances:  Duty cycle, acceptance, aperture, expected events rate (energy, zenith angle) in a pseudo-realistic situation (mean cloudiness as defined by E. Plagnol inspecting ISCCP data) can be collected by end of Phase A, at the level of triggered events.  Joined work with SDA to extend the results to the level of reconstructed events Large effort has to be devoted, in the following months, (mainly beyond Phase A) to plug into the same S/W scheme the various (existing and evolving) parts of the simulation chain, to reach a plug-and-play end-to-end simulation. ESAF is our reference frame .