AirWatch-RD

Collaboration

The EUSO Collaboration, as of today, is made of the following institutions:

- Italy: INFN, CNR (IFCAI and ISAO), INOA, CARSO, INAF (Arcetri and Catania), Universities of Firenze, Genova, Roma1, Palermo, Torino and Trieste.
- France: APC (Paris), ISN (Grenoble), LAPP (Annecy); OdP, LPTHE, IAP (Paris), LAPTH (Annecy); SA, DASE (Paris).
- Japan: RIKEN and ICRR-Tokyo.
- USA: Universities of Alabama (Huntisville), California (Berkley), California (Los Angeles), Texas (Austin), Vanderbilt; NASA Marshall and Goddard.
- Portugal: LIP-Lisboa.

National Responsible: Alessandro Petrolini (Ge)

Location of the experiment: International Space Station or satellite

1. Goal of the experiment

The present R&D project is connected to the EUSO (Extreme Universe Space Observatory) experiment, currently under phase A study by ESA for a possible installation on the International Space Station.The experiment goal is the study of the Extreme High Energy part (E > 3x1019 eV) of the Cosmic Radiation (EHECR), by observing from space the Extensive Air Showers (EAS) produced by the interaction of EHECR with the atmosphere. A large mass of atmosphere can be observed from space and an EAS can be detected by observing the atmospheric nitrogen fluorescence light, isotropically produced during the EAS development, as well as the Cherenkov light diffusely reflected at the Earth.

More on the experiment…

2.

Activities during 2001

In March 2001 ESA approved the phase A for the EUSO experiment, which is foreseen to start in March 2002 for a one-year duration.

During 2001 the Collaboration has started to create its own organization and structure. The experimental apparatus development, optimization and design processes started including the space-related issues.

The following activities were carried on in 2001 in the framework of the INFN AirWatch-R&D program:

Definition and optimization of the observational capabilities of the experiment; definition of specifications for the photo-detector and associated electronics. | 31-12-2001
Functional design of the elementary cell of the photo-detector and feasibility study given the required constraints. Photo-detector layout definition. | 31-12-2001
Characterization of the MAPMT and verification of the compatibility with the requirements imposed by space missions. | 31-12-2001
Feasibility study of a front-end satisfying the requirements imposed by physics and space missions. | 31-12-2001
Definitions of the front-end chip architecture, study of the adaptability of existing chips, functional design and simulation. | 31-12-2001
Further measurements of the expected background levels. | 31-12-2001

Milestones 2002

Realization of a full functional prototype of the photodetector elementary cell and test. | 31-12-2002
Definition of the architecture of the electronics (front-end, trigger and data-handling). | 31-12-2002
Preliminary functional design of the front-end chip. | 31-12-2002
Realization of a functional prototype of a photodetector module. | 31-12-2002
Additional background measurements and measurements from the Earth (study of the reflected/diffused Cherenkov light). | 31-12-2002
Realization of a fast simulation of the experimental apparatus. | 31-12-2002

3. INFN contribution to the experiment in terms of manpower and financial support

Manpower: Five INFN groups (CT, FI, GE, TO and TS) including 46 research associates (21.6 FTE) and 5 technicians (2.8 FTE) plus support from the workshops and engineering design departments of the Sezioni INFN involved.

Budget for the year 2002: 181 kEuro

4. Publications in referred journals (in 2001): 1

5. Number of conference talks (in 2001): 4

6. Number of undergraduate and doctoral thesis on the experiment

- Students: 4
- Ph. D. students: 1

7. Leadership roles and primary responsibilities in the experiment

The following official responsibilities were defined for the EUSO phase A.

- Livio Scarsi: Principal Investigator (PI);
- Alessandro Petrolini, Deputy Instrument Manager;
- Gianrossano Giannini, Science Coordination;
- Piero Galeotti, Member of the Steering Committee;
- Giacomo D'Ali-Staiti, IWG, Simulations responsible;
- Sergio Bottai, IWG, Simulations deputy responsible;
- Marco Pallavicini, IWG, Digital Front-End electronics responsible;
- Paolo Musico,IWG, Digital Front-End electronics deputy responsible;

8. Innovative instruments

Development of a space-based photo-detector with large dimensions (a few squared meters), a few hundreds of thousands channels, single photon sensitive in the near-UV, double hit resolution time of the order of a few tens of nanoseconds, relatively small mass (well below one ton), low power consumption (well below one kW) and compatible with a three-years operation on the International Space Station.

9. Competing experiments

EHECR are currently studied, and will be studied, by experiments on Earth (e.g. HiRes, AGASA and AUGER). As of now EUSO is the first experiment foreseen to observe from space.

The observation from space will complement the observation from the Earth. A space-based NASA experiment (OWL) is foreseen on a longer time-scale. OWL is in fact in the mid-range strategic plan released by NASA in 2000, which puts OWL after 2008.

Compared to AUGER the EUSO experiment is optimized for a higher energy range, partially overlapping the AUGER one.

10. International Committee which has reviewed the experiment

The EUSO experiment is an international experiment carried on by a large Collaboration: Italy, France, Portugal, Japan and US.

It was proposed to ESA in January 2000 and it was reviewed by the following ESA Committees: AWG (Astronomy Working Group), FPAG Fundamental Physics Advisory Group), SSAC (Space Science Advisory Committee), EUB (European User Board) and SPC (Space Program Committee).

The EUSO project has also been presented to CNES in September 2001. It has been recommended for the last selection phase of CNES, which will happen next March.

This project is annually reviewed by INFN National Committee II.

Support to phase A activities comes from IN2P3/CNRS through local scientific committees and through GDR/PHCE in the form of support to EUSO-AUGER mixed activities.

The EUSO US team presented an EUSO proposal within the NASA MIDEX Announcement of Opportunities. The aim of the MIDEX proposal is to support all phases of the EUSO Mission in the period from 2002 to 2009.

Japan phase A activities will be supported by RIKEN internal funds.