The TIC project: tracking gamma rays with a calorimeter Nicola Mori INFN sezione di Firenze 5th HERD workshop CERN - 12th October 2017
Future cosmic-ray experiments Requirements for the high-energy frontier: Acceptance (multi-tev electrons, hadrons at the knee) Energy resolution 2 Collocation in space constraints on weight and power consumption Innovative designs Homogeneous and isotropic calorimeter HERD, CaloCube
The concept 3 Cubic scintillating elements Accepts particles from 5 sides GF*5 CaloCube prototipe: 5x6x18 CsI cubes Sensor: 2 photodiodes per cube Readout: HIDRA chip (2 dinamic ranges per channel) Tested with particle beams at SPS Energy resolution for e- @ 100 GeV ~ 1.5 %
Towards the design of a complete experiment Additional requirements: Particle ID ( silicon detectors) Tracking (and identifcation) of gamma rays Multi-messenger approach Increase of science reach Conventional gamma tracking 4 Pair-production telescope with alternating silicon-passive (e.g. tungsten) layers γ e+e- in tungsten Tracking of the pair with silicon detectors
Ca lo rim et er + tra ck er a cc ep ta nc e Issues with charged particles W c ac r e et rim lo a C ce an t ep Si Calorimeter Heavy ( reduced mass budget for the calorimeter reduced acceptance and en. res.) Thick ( nuclei fragmentation less precise particle ID) Tall ( reduced overall acceptance) 5
Tacking calorimeter lo Ca r e nc a t ce ep c an c t a p ce er c k a ac er tr t e + im er r t e lo im Ca Calorimeter 6 Basic idea: use the calorimeter as an active converter Insert silicon microstrip layers between the top layers of the calorimeter Reconstruction of the axis of the e.m. showers induced by gamma photons Lightweight (silicon only), low-profle tracker for charged particles Plus other ancillary detectors (TOF, AC,...)
Preliminary MC studies Monte Carlo (FLUKA) simulations of 3 different designs (LYSO cubes) Angular resolution (68% PSF) for vertical photons: 1 GeV 10 GeV 100 GeV 7 A: standard B and C: thin detector (low energies) Geometria A 3.62 0.461 0.031 Geometria B 2.54 0.183 0.029 Geometria C 1.70 0.101 0.030 Presented by S. Bottai at 4th HERD workshop in Rome on 9th February 2017
The Tracker-In-Calorimeter (TIC) project Realization and characterization of a prototype of a tracking calorimeter for gamma rays Integrate the CaloCube prototype with spare AMS/DAMPE silicon microstrip layers 8 All the components are already in-house Test beams with electrons (SPS, BTF) in 2018 No GeV gamma beam available worldwide Shower axis reconstruction is identical for gammas and electrons Precise upstream tracking (e.g. conventional silicon tracker) Just approved (29th September) and fnanced by INFN CSN5 Kick-of meeting soon
Outline of the project Integration of the CaloCube prototype with spare AMS/DAMPE silicon detectors Silicon detectors e- beam CaloCube 9 New structure
Description of the project Design and realization of a new support structure Add thin crystals in the front part Modular structure for quick thin/thick crystal interchange MC simulation and event reconstruction With support for silicon layers Assessment of the overall performance Especially for inclined particles Impact on energy resolution Algorithm optimization Beam tests Low energy: BTF Frascati (< 700 MeV) High energy: SPS CERN (~ 30-300 GeV) 10
Summary Simultaneous detection of charged particles and gamma rays poses serious design difculties HERD scientifc objectives require high performance for both particle species The design of TIC aims at being a sweet spot and will be studied with MC and beam tests during next year The project is already approved and fnanced by INFN A successful investigation might lead to a viable option for the optimization of HERD 11