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The SciBar Cosmic ray telescope (SciCRT) is installed on the top of the Sierra Negra volcano with the main goal of observing solar neutrons to investigate the ion acceleration process during solar flares. Using scintillator bars as a medium to stop energetic particles, the SciCRT is capable of recording both energy deposited on the bars and direction of the incoming particles with high resolution. The original DAQ system was used in neutrino oscillation experiment (low event rate), therefore operation of the electronics on cosmic ray experiment is limited. To improve the SciCRT performance as a solar neutron telescope, development of custom made DAQ electronics is essential. Our first step onto this task was the design and construction of a new fast readout back-end board using SiTCP. The installation of this new system on Sierra Negra and its further improvement on the data acquisition for the detector will be analyzed on separate paper on this conference. The development of new front end electronics is the next stage of the upgrading process. To achieve this goal, we are developing new electronics applying the time over threshold (ToT) technique, using a FPGA to process the signal from one 64 channel multi anode photomutiplier tube (MAPMT). In this paper we will present the details of this new system and several tests performed to guarantee its proper operation to detect solar neutrons.

The SciBar Cosmic Ray Telescope (SciCRT) is aimed to help elucidate the acceleration mechanism of high-energy ions that may produce neutrons at the Sun. It is a fully active scintillator tracker which consists of 14,848 plastic scintillator bars, originally constructed for accelerator neutrino oscillation experiments. The SciCRT; it has a huge detector volume compared with conventional Solar Neutron Telescopes (SNTs), e.g. 15 times larger than Mexico SNT. Furthermore, the SciCRT can measure the energy deposition of each particle as neutron ADC data which have not been registered before. Neutron ADC data provide us with a precise measurement of energies deposited at the detector. The SciCRT was deployed at the summit of Mt. Sierra Negra (4,600 m) and began to acquire data in September 2013. Then we partially upgraded the DAQ system developed originally for an accelerator experiment, as the readout rate of the DAQ system was significantly limited for our experiment. This paper highlights sensitivity numerical studies of solar neutrons that the SciCRT is able to register. At first, we focus in the accuracy to determine the spectrum power-law index, assuming an instantaneous emission of solar neutrons. This is required to determine the power-law index within an error of ±1.0 in order to discuss the efficiency of the acceleration. Then in the case of the fixed power-law index, we discuss the capability of discriminating three different lengths of emission times: 0 min, 5 min, and 8 min. Finally we evaluate whether it is possible to discriminate a different combination of these two parameters simultaneously. Thus, we show that data from the SciCRT will unlock the degeneracy problem amid the emission time and the energy spectrum of solar neutrons.

Porcentaje de captura de Sigmodon hirsutus en el Ingenio El Palmar, Puntarenas, Costa Rica. El objetivo de este trabajo fue determinar el porcentaje y distribución de captura de la rata cañera (Sigmodon hirsutus) en el Ingenio el Palmar, Puntarenas, Costa Rica. Se evaluaron tres parcelas de caña de azúcar, con diferente tipo de colindancia (colindancia con caminos = CC, colindancia con bosques = CB, y ausencia de colindancia = AC). El estudio se realizó durante un periodo de ocho meses (diciembre 2013 a julio 2014).Se colocaron treinta trampas de golpe en cuatro ocasiones, de manera bimensual en cada parcela (n = 360) y se estimó la proporción hembra: macho por medio de inspección genital. Las trampas se colocaron en la tarde y se recolectaron a la mañana siguiente utilizando un sistema de posicionamiento global. Sesenta y nueve ratas fueron capturadas durante el estudio y el porcentaje de captura difirió (p < 0,05) entre las parcelas CC y CB. Los porcentajes de captura promedio fueron 34,2; 5,8 y 17,5 para CC, CB y AC, respectivamente. La proporción hembra: macho general fue de 1:1. Estos resultados indican una mayor captura en secciones colindantes con caminos en relación a parcelas colindantes a bosques.

At the top of the Sierra Negra volcano in eastern Mexico($19.0^\circ$N,$97.3^\circ$W) the SciBar Cosmic Ray Telescope (SciCRT) is installed, one of its main purposes is to detect solar neutrons to investigate the ion acceleration process during intense solar flares. Furthermore, thanks to the design and construction of the SciCRT in the form of small and long scintillation bars, large active volume, high energy resolution, and a fast electronics for data processing, particle identification is possible through the analysis of tracks. Considering these properties, species identification of secondary cosmic ray inside the Earth's atmosphere, at a depth about $600g/cm^2$ is possible. In this work, we present an ad-hoc algorithm constructed to distinguish between particle species that cross the active volume of the detector. The aim is to use pattern recognition methods and event reconstruction to achieve this goal.

espanolUn Telescopio de Neutrones Solares (TNS) fue instalado en la cima del volcan Sierra Negra, Pue., Mexico (19.0o N , 97.3o W, 4580 m sobre el nivel del mar); el cual se encuentra en operacion desde el 2004. En este trabajo, utilizamos los valores de la presion barometrica, de la presion dinamica, de la temperatura ambiental y de la humedad relativa obtenidos por una estacion meteorologica cercana al TNS, para calcular los coeficientes de correccion atmosfericos para el flujo registrado de rayos cosmicos. Cuando los datos de rayos cosmicos estan libres de las variaciones de origen atmosferico, analizamos los perfiles de tiempo observados por el TNS durante seis decrecimientos tipo Forbush seleccionados para el periodo 2011-2013. Los resultados obtenidos por varios canales de deposito de energia (30,60,90 MeV) son discutidos para establecer la confiabilidad del TNS para este tipo de eventos. EnglishA Solar Neutron Telescope (SNT) was installed at the summit of Sierra Negra volcano, Pue., Mexico (19.0o N, 97.3o W, 4580 m above sea level); it is in operation since 2004. In this work, values of barometric pressure, dynamic pressure, ambient temperature and relative humidity obtained by a meteorological station close to the SNT were used, to calculate the coefficients of atmospheric correction to the registered cosmic ray flux. Once the cosmic ray data are free from variations of atmospheric origin, the time profiles observed by the SNT during five selected Forbush type decreases during the period 2011-2013 were analysed. Results obtained by several energy deposition channels (30, 60, 90 MeV) are discussed to establish the reliability of the SNT for this type of events.

Solar neutron telescopes (SNT) were designed and installed on high mountains to study particle acceleration mechanisms in solar surface. Of these, SciBar cosmic ray telescope (SciCRT) is a brand new telescope installed on the top of the Sierra Negra volcano in eastern Mexico ($19^{\circ}$N, $97.3^{\circ}$W) composed of roughly 15000 scintillator bars, capable of detecting solar particles with both high efficiency and energy resolution. SciCRT is also useful to study the anisotropy of galactic cosmic ray muons. The implementation of SciCRT as a cosmic ray telescope began on September 2013, with $5/8$ of the complete detector operative. After that, further improvement of the operating conditions on the place were made in order to maintain a stable data acquisition on the severe atmospheric conditions on high mountain (4600 m). In July 2015 we partially upgrade the DAQ system, installing a $10$ times faster readout back-end electronics. The new system was installed only on $1/8$ of the detector and on the top and bottom layers (working as muon detectors and anti-counters for neutrons). The upgrade was motivated by the limited transfer rate of the original DAQ system, designed for an accelerator experiment. With this new system we expect an improvement on the neutron sensitivity of the SciCRT. In this paper we will detail the operation of the new system and analyze the data obtained to evaluate its performance. We will also explain the plans to continue the upgrading process, installing the new DAQ systems on more layers of the telescope and make estimates of the expected future performance of the SciCRT, evaluated through Monte Carlo simulations.