E.Plagnol - Auger-Leeds ESA-Cosmic Vision A Letter of Intent on "Particle Astronomy" ë The context of Cosmic Vision ë "Particle Astronomy" : The physics (short version) ë "Particle Astronomy" : The associated R&D ë The schedule ahead ë A project for the whole community ? Eric Plagnol Member of the EUSO coll. APC-PCC/Collège de France - Paris "On behalf of those who have signed the LoI"

E.Plagnol - Auger-Leeds The context of Cosmic Vision ESA "This announcement is to invite the community to participate in a Call for Themes for Cosmic Vision to assist in developing the future plans of the Cosmic Vision programme of the ESA Directorate of Science " This includes : Nature of physical laws including their immutability in time. Universe: origin and evolution and changing nature of the universe. Quantum world, edges of space, cosmic microwave background and black holes. Complex systems, turbulence. High energy physics beyond the accelerator. The two major themes : 1. Physics and the physical processes in the universe, 2. Chemical and biological aspects of the evolution of the universe. On the 1st of June, a LoI was sent to ESA : " Opening Particle Astronomy to probe and understand the evolving Universe " Signed by 100 physicists

E.Plagnol - Auger-Leeds "Particle Astronomy" : The physics The aim of this Letter of Intent : Extend the field of "radio and photon astronomy" to the domain of "Particle Astronomy" This field is already initiated by Auger, EUSO, Hires, Telescope Array,… We suggest to bring it one step forward with an ambitious space-based device : => Auger and eV < E < … Main physics themes : "Particle Astronomy" with UHECR Detection of HE (cosmogenic) neutrinos Physics beyond the accelerator (interaction cross sections)

E.Plagnol - Auger-Leeds "Particle Astronomy" : The Physics in the case of the GZK GZK recovery  = : E MAX = eV 2 : E MAX =10 21 eV 3 : E MAX = ∞ 4 : E MAX = ∞ and  = 2.45 (1+z) 4 The shape of the UHECR depends on : -The number of sources within GZK, -The shape of the energy spectra at the source, -The maximum energy produced at the source, -The influence of magnetic fields, - …

E.Plagnol - Auger-Leeds "Particle Astronomy" : The associated R&D We believe this can be achieved by a space-based detector (fluorescence, radio,…). To conceive and study this detector, an ambitious R&D program must be associated ( ). This could address the development of : Very efficient UV detectors (total efficiency ≥ 50%) Large FOV and large area UV optics The deployability of large detectors in space A sophisticated space-based electronics and trigger …

E.Plagnol - Auger-Leeds The schedule ahead The LoI will be examined by ESA-D/Sci committees : AWG-FPAG-SSAC September 2004 : Open Workshop in Paris :scientific relevance, support of the wider community and early identification of technology challenges Autumn 2004 : an analysis of the major technologies needed to develop the selected themes should be finalised and Technology Reference Missions should be identified for future studies. Participants from ground-based astronomy (e.g. nominated by ESO) could be invited to explore synergies. November 2004: There will be a progress report to SPC. Spring 2005 :The Cosmic Vision plan will be presented to the SPC + public presentations

E.Plagnol - Auger-Leeds A project for the whole community ? We believe that such a program should be coordinated, very closely, between ground based devices (e.g. Auger) and the "space detector groups". The time frame (≈ 2020) does not put it in conflict with present and "shorter term" projects (Auger-North, EUSO). In order to succeed : -We will need the support of the whole community and an agreement on the goals of this project. -Convince the (space-based) "Astronomy" community that it is one step forward in the understanding of the universe. -Build a solid R&D project with a web of laboratories and industrial companies.