RevMexAA (Serie de Conferencias), 00, 1–1 (2007)
H. Asorey1,2,3 , A. Balaguera-Rojas3 , L. A.
Núñez3,4 , J. Núñez-Castiñeyra5 , J. Peña-Rodrı́guez
, J. Rodriguez-Ferreira3 , J. D. Sanabria-Gómez3 ,
C. Sarmiento-Cano3 and M. Suárez-Durán3 , for
The MuTe Collaboration7
In Colombia volcanoes are dangerous because of
their eruptive history and location close to urban
areas. To image the mean density profile of volcanoes reveals internal structures and helps to understand their behavior during future eruptions. At
Universidad Industrial de Santander we are working on the design, construction, and calibration of a
MUon TElescope (MuTe) that uses muongraphy to
create a global density profile of the interior of the
volcano. The signal is obtained by measuring, at different sites, the flux of muons traversing the volcano
and arriving at the instrument detector in all the directions that spans the telescope field of view (FOV).
The design of the instrument is based on simulations
in order to make instrumental decisions regarding
the extreme environmental conditions. The mechanical concept was constrained also by the size, installation and handling of the telescope; the use of large,
heavy or complex parts was avoided. The final concept is a rigid, lightweight and stable metallic structure made of steel in order to host at least two scintillator detection matrices with variable separation and
a metallic cubic tank for a water Cherenkov detector
(WCD) acting as an active absorbent, placed on the
backside of the telescope. The azimuth and elevation angles of the full structure are also modifiable.
MuTe uses two particle detection techniques: scintillation and Cherenkov radiation detection in water. Each of the two detection matrices is composed
by an array of 30 × 30 strips of plastic scintillators
(0.01 m×0.04 m×1.2 m), giving 900 square pixels of
0.04 m side. Each strip corresponds to a signal channel (60 in total) and has a scintillator optical fiber
that collects light produced by charged particle hits.
The signal is collected by 60 silicon photomultipliers
for subsequent recording and analysis by the readout electronics system based on a FPGA and 64 upper and lower level discriminators that produces an
output logic pulse detection only if its input signal
exceeds a preset threshold level. A hit on both detection matrices indicates the direction of a particle
traversing the FOV. The WCD uses a large photomultiplier to collect and measure the deposited energy of the traversed particle, allowing an enhanced
muon-noise separation by looking for signal coincidences. The telescope must be autonomous and its
correct operation needs to be assured for months. To
achieve this, power consumption is supplied by solar
power system, data is pretreated by a single board
computer, stored locally and transferred by GSM or
satellite links connections. Atmospheric conditions,
environmental variables and greenhouse gasses concentrations are measured by a meteorological station
that was designed especially for that purpose.
Laboratorio Detección de Partı́culas y Radiación, Centro
Atómico Bariloche e Instituto Balseiro, Comisión Nacional de
Energı́a Atómica, Av. E. Bustillo 9500, (8400) San Carlos de
Bariloche, Argentina.
2 Escuela de Tecnologı́a y Medio Ambiente, Sede Andina, Universidad Nacional de Rı́o Negro, Mitre 630, (8400) San Carlos
de Bariloche, 8400, Argentina.
3 Escuela de Fı́sica, Facultad de Ciencias. Universidad Industrial de Santander, Carrera 27 calle 9 ciudad universitaria
Bucaramanga, 680002 Colombia.
4 Departamento de Fı́sica, Universidad de Los Andes, Mérida,
5 Escuela de Diseño Industrial, Universidad de Los Andes,
Mérida, Venezuela.
6 Escuela de Ingenierı́as Eléctrica, Electrónica y de Telecomunicaciones, Grupo de Investigación en Control, Electrónica,
Modelado y Simulación, Facultad de Ingenierı́as Fisicomecánicas. Universidad Industrial de Santander, Carrera
27 calle 9 ciudad universitaria Bucaramanga, 680002 Colombia.
7 http://halley.uis.edu.co/fuego, see the full list of members and institutions at http://halley.uis.edu.co/fuego/elproyecto/autoresmute/ (mailto: [email protected]).