Monte Carlo simulations of soft proton flares: testing the physics with XMM-Newton

Low energy protons (<100-300 keV) in the Van Allen belt and the outer regions can enter the field of view of X-ray focusing telescopes, interact with the Wolter-I optics, and reach the focal plane. The use of special filters protects the XMM-Newton focal plane below an altitude of 70000 km, but above this limit the effect of soft protons is still present in the form of sudden flares in the count rate of the EPIC instruments, causing the loss of large amounts of observing time. We try to characterize the input proton population and the physics interaction by simulating, using the BoGEMMS framework, the proton interaction with a simplified model of the X-ray mirror module and the focal plane, and comparing the result with a real observation. The analysis of ten orbits of observations of the EPIC/pn instrument show that the detection of flares in regions far outside the radiation belt is largely influenced by the different orientation of the Earth's magnetosphere respect with XMM-Newton's orbit, confirming the solar origin of the soft proton population. The Equator-S proton spectrum at 70000 km altitude is used for the proton population entering the optics, where a combined multiple and Firsov scattering is used as physics interaction. If the thick filter is used, the soft protons in the 30-70 keV energy range are the main contributors to the simulated spectrum below 10 keV. We are able to reproduce the proton vignetting observed in real data-sets, with a 50\% decrease from the inner to the outer region, but a maximum flux of 0.01 counts cm-2 s-1 keV-1 is obtained below 10 keV, about 5 times lower than the EPIC/MOS detection and 100 times lower than the EPIC/pn one. Given the high variability of the flare intensity, we conclude that an average spectrum, based on the analysis of a full season of soft proton events is required to compare Monte Carlo simulations with real events

Entanglement entropy from non-equilibrium Monte Carlo simulations

We study the entanglement entropy in lattice field theory using a simulation algorithm based on Jarzynski's theorem. We focus on the entropic c-function for the Ising model in two and in three dimensions: after validating our algorithm against known analytical results from conformal field theory in two dimensions, we present novel results for the three-dimensional case. We show that our algorithm, which is highly parallelized on graphics processing units, allows one to precisely determine the subleading corrections to the area law, which have been investigated in many recent works. Possible generalizations of this study to other strongly coupled theories are discussed.Comment: 1+33 pages; v2: typos corrected, matches published versio

Parallel waveform extraction algorithms for the Cherenkov Telescope Array Real-Time Analysis

The Cherenkov Telescope Array (CTA) is the next generation observatory for the study of very high-energy gamma rays from about 20 GeV up to 300 TeV. Thanks to the large effective area and field of view, the CTA observatory will be characterized by an unprecedented sensitivity to transient flaring gamma-ray phenomena compared to both current ground (e.g. MAGIC, VERITAS, H.E.S.S.) and space (e.g. Fermi) gamma-ray telescopes. In order to trigger the astrophysics community for follow-up observations, or being able to quickly respond to external science alerts, a fast analysis pipeline is crucial. This will be accomplished by means of a Real-Time Analysis (RTA) pipeline, a fast and automated science alert trigger system, becoming a key system of the CTA observatory. Among the CTA design key requirements to the RTA system, the most challenging is the generation of alerts within 30 seconds from the last acquired event, while obtaining a flux sensitivity not worse than the one of the final analysis by more than a factor of 3. A dedicated software and hardware architecture for the RTA pipeline must be designed and tested. We present comparison of OpenCL solutions using different kind of devices like CPUs, Graphical Processing Unit (GPU) and Field Programmable Array (FPGA) cards for the Real-Time data reduction of the Cherenkov Telescope Array (CTA) triggered data.Comment: In Proceedings of the 34th International Cosmic Ray Conference (ICRC2015), The Hague, The Netherlands. All CTA contributions at arXiv:1508.0589

CTA Data Management Quick-Look and Real-Time (On-Site) Analysis Detailed User Requirement Document

In the context of DM WP of the CTA observatory a Detailed User Requirement document (URD) for the CTA Data Management Quick-Look and Real-Time Analysis (called Science Monitoring subsystems) has been proposed. This document addresses the detailed user requirements for the Science Monitoring subsystem of the CTA observatory. The purpose of this document is to serve as a tool to gather the user requirements that will drive the development of software of this subsystem. In addition, it could be used as a guide to select and re-use existing software, to be identified at a later stage. The use cases are classified in two levels: user and sub-function. The use cases at user level are use cases of the system that are connected directly with user action; the use cases at sub-function level are use cases at system level that are part of a most general use case at user level: they are put in evidence to better understand the use of the system and the classification of requirements. For some use cases the flow of events and related test procedure are reported. Tables with links between use cases and functional requirements are reported. It is important to indicate that the requirements in this document are just aimed at the software development process. This document describes what the software should be able to do but not how it will be implemented; this is the aim of the software requirement document. Instrumental characteristics and observatory performance requirements are analysed in the Performance Requirements document [R3] and will not be considered here

The AGILE Gamma-Ray observatory: software and pipelines

In this paper is described the approach used to develop the software system of the AGILE γ-ray Observatory, from the definition phase to construction, verification and calibration activities of the satellite, until operations for scientific observations. Flexible software architectures, effective software management workflow, new algorithms (from payload simulators to reconstruction algorithms, from detection algorithms for Real-Time Analysis systems to the follow-up of science alerts in the multi-wavelenght and multi-messenger context) and team management approach are described. The approach followed by the AGILE Team in more than twenty years of work is a key element of the success of the AGILE Observatory, and the foundation for the involvement in new high-energy telescopes and observatories. Our legacy is not only in experience and tools but also in lesson learned, that are described in this work

ASTRI Mini-Array Use Cases of the Power Management System Collector

The ASTRI Mini-Array (MA) is an INAF project to construct and operate an experiment to study gamma-ray sources emitting at very high-energy in the TeV spectral band. This document defines the Use Cases of the Power Management System Collector (PMSC)

AGILE 3D Viewer User Manual

AGILE is an ASI (Italian Space Agency) Small Scientific Mission dedicated to high-energy astrophysics which was launched on April 23 2007 from Satish Dawan Space Centre, India) on a PSLV-C8 rocket. The AGILE Payload is composed of three instruments: a Tungsten-Silicon Tracker designed to detect and image photons in the 30 MeV-50 GeV energy band, an X-ray imager called SuperAGILE that works in the 18-60 keV energy band, and a Minicalorimeter that detects gamma-rays or particle energy deposits between 300~keV and 200~MeV. The instrument is surrounded by an anti-coincidence (AC) system. We have developed a set of Quick Look software tools in the framework of the Test Equipment (TE) and the Electrical Ground Support Equipment (EGSE. This s/w is required in order to support all the assembly, integration and verification (AIV) activities to be carried out for the AGILE mission, from data handling unit level to payload integrated level, calibration campaign, launch campaign and in-orbit commissioning. These software tools have enabled us to test the engineering performance and to perform a health check of the Payload during the various phases. We have used an incremental development approach and a common framework to rapidly adapt our software to the different requirements of the various phases

ASTRI Mini-Array Use Cases of the Telescope Service Cabinet Control System

The ASTRI Mini-Array (MA) is an INAF project to construct and operate an experiment to study gamma-ray sources emitting at very high-energy in the TeV spectral band. This document defines the Use Cases of the Telescope Service Cabinet Control System (TSCCS)