Download Extreme Energy Events (EEE) – Science inside Schools The EEE

Extreme Energy Events (EEE) – Science inside Schools
The EEE Project has produced an effective impact on the world of
education at high school level, introducing a totally innovative and
advanced way of teaching physics. The Project consists in the creation of
an array of real forefront research laboratories inside schools, where
teachers and students act as the main characters.
The first phase of the EEE Project has been implemented and funded in
Italy. To this purpose, agreements have been signed with:
- the Ministry of Education, University and Research (MIUR),
- the Italian National Institute for Nuclear Physics (INFN),
- the European Organization for Nuclear Research (CERN),
- the Foundation "Ettore Majorana" and Centre for Scientific Culture
(FEMCCS),
- the "Enrico Fermi" Historical Museum of Physics and Centre for
Studies and Research (Enrico Fermi Centre),
- various high schools and technical institutes, involved in the Project.
The EEE Project is a large experiment whose main goal is the
investigation of the origin of cosmic rays. The experiment is not
performed in research centres or labs but in high schools distributed
across Italy, with the decisive contribution of students and teachers. In
each school involved in the Project, a "telescope" is built using the most
modern and advanced particle detectors, the Multigap Resistive Plate
Chambers (MRPCs). School's telescopes are to be set in coincidence with
each other thanks to GPS equipment, in order to reveal cosmic muons
from extensive air showers (as large as entire towns or even more)
produced by the highest-energy primary cosmic rays. The students are
given the very important task to build the detectors starting from basic
elements, thus making them realize how high-precision instruments can
be obtained starting from simple materials. The construction of the
detectors occurs at CERN where the students have the opportunity to
spend some time and visit the largest and most powerful particle physics
laboratory in the world.
The Project stems from the following considerations. On the Earth we
live immersed in a flow of "rays", called cosmic because they come from
the farthest reaches of outer space, far beyond the Moon, the Sun and the
stars visible to the naked eye. These rays, which travel for millions and
millions of years, are essentially made of protons and constitute the "ash"
of the Big Bang. Arriving near to the Earth, cosmic protons meet the
highest layers of the atmosphere. When a proton encounters a layer of
1
matter, it interacts with the nuclei of which matter itself is made. In the
interaction, other subnuclear particles are produced but they live very
shortly (billionths of a second). In their short life they are transformed
into other particles whose last stage are muons. At sea level the bulk of
cosmic rays is made of muons. Muons are particles identical to electrons
that are part of atoms and molecules familiar to us. The unique diversity
of muons is to be 200 times heavier than electrons. The reason for this
difference is still one of the unsolved problems in physics today. Another
open question is about the origin: where, when and how the cosmic
protons originate. Cosmic rays may also have significant implications in
our lives, with effects ranging from climate change to genetic mutations,
to mention only a few examples of the problems related to their study.
Here then the interest in studying high-energy cosmic events: Extreme
Energy Events (EEE).
The data that are collected in each school are an original contribution to
the study of cosmic rays. Dealing with cosmic rays, students and their
teachers acquire a direct interest in the new problems related to particle
physics, astrophysics and high technology. As said, the Project is
structured on a modular basis, since in each participating school a
telescope is built and then locally monitored and managed, but at the
same time a national EEE network is set-up, connecting all the schools.
The goal of the EEE Project is therefore to bring science into the heart of
young people, even the very young, through a direct action that begins
when students feel they have personally achieved the construction of an
instrument, and continues when students realize they are involved in the
elaboration and analysis of data that are at the frontiers of scientific
thought.
The construction of a network, which in general permits the exchange of
scientific information at this level, is in itself a goal of great importance
that can be exploited for additional applications (seismography,
environmental pollution control, etc.), always related to the diffusion of
scientific culture. In this perspective, the establishment of a network able
to detect cosmic particles should be considered as a first step of the EEE
Project.
Today 47 EEE telescopes are ready, 41 are fully operative, 6 are near to
operate, and data acquisition is ongoing, looking for coincidence events
between close and distant telescopes. Of these 47 telescopes, 42 are
installed in Italian high schools, while 3 are in INFN Units and 2 at
CERN, as shown in Figure 1. Over 25 schools are currently in waiting list
to join the EEE Project in a very near future. The goal of the Project is to
2
equip up to100 high schools in Italy, then to enlarge the EEE Project by
including other countries all over the Earth surface. In this respect,
scientific institutions such as the Budker Institute of Novosibirsk, Russia,
and the Institute of High Energy Physics (IHEP) of Beijing, Cina, have
already expressed their interest in the Project.
Figure 1: Map of the EEE telescopes (November 2014).
The EEE Project has produced many publications, presentations at
international conferences and theses. Publications and other materials,
including multimedia, are available on the EEE Project website:
http://www.centrofermi.it/eee. The list of scentific articles published so
far is given at the end of this section.
3
A sketch of the type of detector chosen, namely the Multigap Resistive
Plate Chamber (MRPC), is shown in Figure 2. This type of gaseous
detector, also adopted in ALICE experiment at the Large Hadron Collider
(LHC) at CERN, has been conceived in a suitably simplified version for
the EEE Project.
Figure 2: Cross section of the MRPC showing its basic design in terms of inner layers
(top); top view of the MRPC together with its x-y reference system (bottom).
Three detectors for each telescope are used in the schools, in order to
accurately measure the direction of incoming muons and their time of
arrival. The scheme of the EEE telescope system including the necessary
equipment, namely the mechanical structure, PC, oscilloscope, GPS
system and readout electronics of the signals, is shown in Figure 3.
4
Figure 3: Technical design of the EEE telescope equipped with a mechanical
accessory to allow varying the distance between the MRPC detectors, where a
traversing muon is indicated as a red arrow (left); scheme of the EEE telescope
system made of MRPC detectors, front-end electronics, data acquisition and
distribution devices (right).
The construction of the MRPC detectors is carried out by the students and
teachers involved in the Project, assisted by scientific and technical staff
from INFN and Enrico Fermi Centre, at the CERN laboratory in Geneva.
The detectors built at CERN are then transported to the school. A real
EEE telescope is shown in Figure 4.
Figure 4: Photograph of one EEE telescope installed in one school in Turin.
The MRPC detectors’ performances are tested on site at the telescope,
measuring space and time resolution. A successful process of collecting
data for the study of cosmic rays and the search for similarities between
the telescopes in different schools is running continuously.
5
The EEE Project has already demonstrated its capability to detect
extensive air showers. The analysis of time correlations for the detection
of muons belonging to the same shower has been successfully performed
on data acquired with telescope clusters installed in Bologna, Cagliari,
L’Aquila and Frascati (Roma). Figure 5 illustrates the first impressive
results of the time coincidence analysis performed on data acquired with
two EEE telescopes in L’Aquila. It is the first detection of extensive air
showers ever done with MRPC detectors installed at schools, outside
research laboratories.
Figure 5: First coincidences observed by two EEE telescopes in L'Aquila, 180 m
distant with respect to each other.
The EEE Project is also able to measure intensity variations in the cosmic
ray flux. Among the non-periodic intensity variations, rapid decreases of
6
the galactic cosmic ray flux due to solar activity (the so-called Forbush
decreases) are the most common and the most interesting. They will be
referred to here as GCR decreases.
On February 2011, an important GCR decrease was observed for the
muon component of the cosmic ray flux by the EEE telescopes and this
variation was compared with what measured by the Oulu Cosmic Ray
Station in Finland. The Oulu station is devoted to the measurement of the
neutron component of the cosmic ray flux. The phenomenon was
observed by two different EEE telescopes, one installed in Catania and
the other in Altamura. This is again a result absolutely original in terms
of detection setup.
Figure 7: The March 2012 GCR decrease, as observed by (a) the Oulu and Rome
detectors of the Neutron Monitor Network and by (b) the Altamura, (c) Catania, and
(d) Bologna EEE telescopes. For an easier comparison, the EEE measurements are
superimposed to the Rome data.
7
On March 2012, another spectacular GCR decrease, associated to one of
the largest recent solar flares, was simultaneously observed by three
detection sites of the EEE network. The figure showing the flux of the
secondary cosmic rays as a function of time, for two neutron monitors (a)
located in Oulu and Rome, and for the EEE muon telescopes (b, c, d)
placed, respectively, in Altamura, Catania and Bologna has been given
the privilege to appear on the cover page of the journal which published
the result, as shown in Figure 7.
In 2014, a pilot run involving the simultaneous and, for the first time,
completely automatic acquisition and data storage of EEE events from 15
schools at the INFN CNAF computer centre of Bologna has just been
performed. Over a billion of events have been collected in about one
month. The search for coincidence events from near and distant
telescopes will be the main goal of the data analysis, taking advantage of
the tracking capablity of the telescopes to select different impact angles.
Figure 8 shows the control room at Pisa INFN Unit for the EEE
telescopes of Tuscany.
Figure 8: The EEE control room in Pisa INFN Unit.
In the years to come, the EEE Project should be allowed to reach its full
potential of 100 telescopes in Italian High Schools, by means of an
appropriate investement in terms of funding and manpower. In this way
the Project will be able to harvest major physics results and, at the same
time, fulfil its mission to effectively focus young generations' attention on
the importance of science thanks to their decicated and direct
involvement.
8
References
- Abbrescia M. et al. (EEE Collaboration), Cosmic rays Monte Carlo
simulations for the Extreme Energy Events Project, Eur. Phys. J Plus
129 (2014) 166
- Abbrescia M. et al. (EEE Collaboration), Time correlation
measurements from extensive air showers detected by the EEE
telescopes, Eur. Phys. J Plus 128 (2013) 148
- Abbrescia M. et al. (EEE Collaboration), The EEE experiment project:
status and first physics results, Eur. Phys. J Plus 128 (2013) 62
- Abbrescia M. et al. (EEE Collaboration), The EEE Project: cosmic
rays, multigap resistive plate chambers and high school students,
JINST, 7 (2012) P11011
- Abbrescia M. et al. (EEE Collaboration), The EEE experiment: cosmic
rays, multigapresistive plate chambers and high school students, XI
Workshop on Resistive Plate Chambers and Related Detectors, PoS
(RPC2012) 012
- Abbrescia M. et al. (EEE Collaboration), Observation of the February
2011 Forbush decrease by the EEE telescopes, Eur. Phys. J. Plus 126
(2011) 61
- Abbrescia M. et al. (EEE Collaboration), First detection of extensive
air showers with the EEE experiment, Il Nuovo Cimento B-Basic
Topics in Physics 125 (2010) 243-254
- Abbrescia M. et al. (EEE Collaboration), Towards the installation and
use of an extended array for cosmic ray detection: The EEE Project,
Nuclear Physics B (Proc. Suppl.) 190 (2009) 38-43
- Abbrescia M. et al. (EEE Collaboration), Performance of a six gap
MRPC built for large area coverage, Nuclear Instruments and
Methods in Physics Research A, 593 (2008) 263-268
- Abbrescia M. et al. (EEE Collaboration), Extreme Energy Events
Project: Construction of the detectors and installation in Italian High
Schools, Nuclear Instruments and Methods in Physics Research A, 588
(2008) 211-214
- Abbrescia M. et al. (EEE Collaboration), Multigap Resistive Plate
Chambers for EAS study in the EEE Project, Proceedings of the 30th
International Cosmic Ray Conference, Vol. 5, HE part 2 (2008) 1565–
1568
- An S. et al. (EEE Collaboration), Multigap resistive plate chambers for
EAS study in the EEE Project, Nuclear Instruments and Methods in
Physics Research A, 581 (2007) 209-212
9
- Antolini R. et al. (EEE Collaboration), The EEE Project: status and
perspectives, Nuclear Physics B (Proc. Suppl.), 165 (2007) 333-340
- Zichichi A., Progetto "La Scienza nelle Scuole": EEE – Extreme
Energy Events, Società Italiana di Fisica, Bologna, 1st Ed. 2004; 2nd
Ed. 2005, 3rd Ed. 2012, 4th Ed. 2014
10