R. Conceição

The Muonic longitudinal shower profiles at production

Abstract In this paper the longitudinal profile of muon production along the shower axis is studied. The characteristics of this distribution is investigated for different primary masses, zenith angles, primary energies, and different high energy hadronic interaction models. It is found that the shape of this distribution displays universal features similar to what is known for the electromagnetic profile. The relation between the muon production distribution and the longitudinal electromagnetic evolution is also discussed.

Teleconsultation for cooperative acquisition, analysis and reporting of ultrasound studies

We have developed a teleconsultation system to support cooperation between doctors at different institutions in the acquisition, analysis and reporting of ultrasound studies. All the relevant activities were supported by the application. The system enabled remote supervision of the ultrasound study as it was being performed, cooperative static image acquisition and analysis, as well as report writing. Cooperative analysis of previously acquired studies was also possible. The system is undergoing evaluation in five hospitals in Portugal.

Interpretation of measurements of the number of muons in extensive air shower experiments

Abstract In this paper we analyze the energy evolution of the muon content of air showers between 1018.4 and 1019.6 eV to be able to determine the most likely mass composition scenario from future number of muons measurements. The energy and primary mass evolution of the number of muons is studied based on the Heitler–Matthews model and Monte Carlo simulation of the air shower. A simple model to describe the evolution of the first and second moments of number of muons distributions is proposed and validated. An analysis approach based on the comparison between this model’s predictions and data to discriminate among a set of composition scenarios is presented and tested with simulations. It is shown that the composition scenarios can be potentially discriminated under the conditions imposed by the method. The discrimination power of the proposed analysis is stable under systematic changes of the absolute number of muons from model predictions and on the scale of the reconstructed energy.

Autonomous RPCs for a Cosmic Ray ground array

We report on the behaviour of Resistive Plate Chambers (RPC) developed for muon detection in ultra-high energy cosmic ray (UHECR) experiments. The RPCs were developed for the MARTA project and were tested on field conditions. These RPCs cover an area of

LATTES: a new gamma-ray detector concept for South America

1.5 \times 1.2\,{m^2}

MARTA: a high-energy cosmic-ray detector concept for high-accuracy muon measurement

and are instrumented with 64 pickup electrodes providing a segmentation better than

LATTES: a novel detector concept for a gamma-ray experiment in the Southern hemisphere

20\,

Mass Composition and Cross-section from the Shape of Cosmic Ray Shower Longitudinal Profiles

cm. By shielding the detector units with enough slant mass to absorb the electromagnetic component in the air showers, a clean measurement of the muon content is allowed, a concept to be implemented in a next generation of UHECR experiments. The operation of a ground array detector poses challenging demands, as the RPC must operate remotely under extreme environmental conditions, with limited budgets for power and minimal maintenance. The RPC, DAQ, High Voltage and monitoring systems are enclosed in an aluminium-sealed case, providing a compact and robust unit suited for outdoor environments, which can be easily deployed and connected. The RPCs developed at LIP-Coimbra are able to operate using a very low gas flux, which allows running them for few years with a small gas reservoir. Several prototypes have already been built and tested both in the laboratory and outdoors. We report on the most recent tests done in the field that show that the developed RPCs have operated in a stable way for more than 2 years in field conditions.

Design and expected performance of a novel hybrid detector for very-high-energy gamma-ray astrophysics

Currently the detection of Very High Energy gamma-rays for astrophysics rely on the measurement of the Extensive Air Showers (EAS) either using Cherenkov detectors or EAS arrays with larger field of views but also larger energy thresholds. In this talk we present a novel hybrid detector concept for a EAS array with an improved sensitivity in the lower energies (

Long term Experience in Autonomous Stations and production quality control.

\sim 100\,