Juan Jose Blanco

CIRCUMSOLAR ENERGETIC PARTICLE DISTRIBUTION ON 2011 NOVEMBER 3

Late on 2011 November 3, STEREO-A, STEREO-B, MESSENGER, and near-Earth spacecraft observed an energetic particle flux enhancement. Based on the analysis of in situ plasma and particle observations, their correlation with remote sensing observations, and an interplanetary transport model, we conclude that the particle increases observed at multiple locations had a common single-source active region and the energetic particles filled a very broad region around the Sun. The active region was located at the solar backside (as seen from Earth) and was the source of a large flare, a fast and wide coronal mass ejection, and an EIT wave, accompanied by type II and type III radio emission. In contrast to previous solar energetic particle events showing broad longitudinal spread, this event showed clear particle anisotropies at three widely separated observation points at 1 AU, suggesting direct particle injection close to the magnetic footpoint of each spacecraft, lasting for several hours. We discuss these observations and the possible scenarios explaining the extremely broad particle spread for this event.

Energetic-particle-flux decreases related to magnetic cloud passages as observed by the Helios 1 and 2 spacecraft

It has been observed that a magnetic cloud (MC) can affect the propagation conditions of solar energetic particles and low-energy cosmic rays. This effect is commonly observed as a decrease in the energetic-particle fluxes, which are partially excluded from the interior of the cloud. The twin spacecraft Helios 1 and Helios 2 explored the inner heliosphere between 0.29 AU and 1 AU from the mid 1970s to early 1980s. The E6 Experiment onboard Helios is the energetic-particle detector able to measure electrons, protons and alphas in the range of 300 keV/n to >50 MeV/n. It has been shown previously that, in absence of strong solar-particle events, the single detector rates of the E6 anti-coincidence and saphire Cherenkov detectors are sensitive to cosmic rays with rigidities above GV. Because their statistical precision is in the order of hundreds of counts per second, both detectors are very well suited for studying the short-term decreases observed in their count rates during magnetic cloud passages. A total of 35 magnetic clouds have been identified at the Helios locations. Nineteen of them were free of solar energetic-particle contamination. This subset led us to investigate the effect of magnetic clouds on the galactic cosmic ray (GCR) flux. The depth of the decreases are studied in terms of the solar wind and magnetic field properties of the magnetic cloud. We found dependences with the MC magnetic field strength, magnetic rigidity and with the MC time of flight, with the latter supporting the idea of magnetically closed MCs, i.e. with the two legs rooted in the Sun. We also studied MC properties and found evidence of MC expansion during its journey through the inner heliosphere.

A year of operation of Melibea e-Callisto Solar Radio Telescope

The e-CALLISTO (Compound Astronomical Low-cost Low-frequency Instrument for Spectroscopy and Transportable Observatory) is a worldwide radio-spectrograph network with 24 hours a day solar radio burst monitoring. The e-CALLISTO network is led by the Swiss Federal Institute of Technology Zurich (ETHZ Zurich), which work up collaborations with local host institutions. In 2013 the University of Alcala joined the e-CALLISTO network with the installation of two Solar Radio Telescopes (SRT): the EA4RKU-SRT that was located at the University of Alcala from January 2013 till June 2013 and the Melibea-SRT that is located at Peralejos de las Truchas (Guadalajara) in operation from June 2013. The Spanish e-Callisto SRTs provide routine data to the network. We present examples of type III and type II radio-bursts observed by Melibea during its first year of operation and study their relation with soft X-ray flares observed by GOES and Coronal Mass Ejections (CMEs) and Solar Energetic Particle (SEP) events observed by space-borne instrumentation.

TRAGALDABAS: a new RPC based detector for the regular study of cosmic rays

Cosmic rays of a wide range of energies are arriving permanently to the Earth coming from the Sun or beyond our solar system. Their study is of interest for many fields of research. A high granularity and high time resolution cosmic ray tracking detector, TRAGALDABAS, based on timing RPC cells, has been recently installed at the Faculty of Physics of the Univ. of Santiago de Compostela, in Spain, in order to go deeper into the understanding of the cosmic rays arriving to the Earth surface. In this article, the layout and the main performances of the detector are shown together and some of the expected research fields are discussed.

Embedded data acquisition system for neutron monitors

This article presents the design and implementation of a new data acquisition system to be used as replacement for the old ones that have been in use with neutron monitors for the last decades and, which are eventually becoming obsolete. This new system is also intended to be used in new installations, enabling these scientific instruments to use todays communication networks to send data and receive commands from the operators. This system is currently running in two stations: KIEL2, in the Christian-Albrechts-Universitat zu Kiel, Kiel, Germany, and CALMA, in the Castilla-La Mancha Neutron Monitor, Guadalajara, Spain.

Cosmic rays below 15 GeV and the current rising solar activity phase

The cosmic ray component in the range of energies below 15 GeV is strongly affected by transient phenomena related to solar activity. Cosmic rays and solar particles with energies between 0.5 and 15 GeV can be observed by neutron monitors at ground level. In absence of solar activity, the background counting rate registered by neutron monitors is dominated by the galactic cosmic ray component, showing only long-term variations correlated with the solar cycle. During active periods, short-term temporal variations can be observed in close association with solar activity phenomena such as flares and coronal mass ejections. Most of these transients can produce a strong response in the magnetosphere. The aim of this work is to study the relationship between neutron monitor measurements and the magnetospheric response observed in Dst index, paying special attention to their connection with solar transient phenomena during the current rising solar activity phase.

The Neutron Monitor Control Panel

This work presents the current status and future plans of the Neutron Monitor Control Panel (NMCP), a new software developed to aid the operator in typical station maintenance and configuration operations. This software is integrated with the new so-called NOAS data acquisition system and it can be accessed using a supported web browser. It features a visual inspection tool to help the operator to identify spikes in the data, trace the origin of the spike back to the raw readings of each counter tube and pressure reading, and mark the data as invalid in the Neutron Monitor Database if desired. The software also provides information about station operation status, some descriptive statistics about current data being recorded and, in the future, will provide an interface to configure station parameters.

TRAGALDABAS: A new high resolution detector for the regular study of cosmic rays

Research on cosmic rays is of big interest either for getting a better understanding about their origin and properties or because they offer very valuable information about the galactic, the solar and the Earths environment. In order to improve our knowledge of all those fields, a high resolution cosmic ray tracking detector, TRAGALDABAS, is being commissioned at the Faculty of Physics of the Univ. of Santiago de Compostela (Spain). In this article we make overview of the main performances of the detector and we present some very preliminary results showing that the detector is taking good data, and that we are gathering a valuable sample of events, ready to be analyzed.