FIRST NuSTAR OBSERVATIONS of MRK 501 WITHIN A RADIO to TeV MULTI-INSTRUMENT CAMPAIGN

© 2015. The American Astronomical Society. All rights reserved.. We report on simultaneous broadband observations of the TeV-emitting blazar Markarian 501 between 2013 April 1 and August 10, including the first detailed characterization of the synchrotron peak with Swift and NuSTAR. During the campaign, the nearby BL Lac object was observed in both a quiescent and an elevated state. The broadband campaign includes observations with NuSTAR, MAGIC, VERITAS, the Fermi Large Area Telescope, Swift X-ray Telescope and UV Optical Telescope, various ground-based optical instruments, including the GASP-WEBT program, as well as radio observations by OVRO, Metsähovi, and the F-Gamma consortium. Some of the MAGIC observations were affected by a sand layer from the Saharan desert, and had to be corrected using event-by-event corrections derived with a Light Detection and Ranging (LIDAR) facility. This is the first time that LIDAR information is used to produce a physics result with Cherenkov Telescope data taken during adverse atmospheric conditions, and hence sets a precedent for the current and future ground-based gamma-ray instruments. The NuSTAR instrument provides unprecedented sensitivity in hard X-rays, showing the source to display a spectral energy distribution (SED) between 3 and 79 keV consistent with a log-parabolic spectrum and hard X-ray variability on hour timescales. None (of the four extended NuSTAR observations) show evidence of the onset of inverse-Compton emission at hard X-ray energies. We apply a single-zone equilibrium synchrotron self-Compton (SSC) model to five simultaneous broadband SEDs. We find that the SSC model can reproduce the observed broadband states through a decrease in the magnetic field strength coinciding with an increase in the luminosity and hardness of the relativistic leptons responsible for the high-energy emission

Behavioral Responses towards Risk Mitigation : An Experiment with Wild Fire Risks

What are the behavioral effects of voluntary self-protection in situations where the probabilities are unknown to the agent? Virtually all naturally occurring environments of risk management involve subjective probabilities, and many allow decision makers to voluntarily mitigate risk using self-protection activities. To examine this environment we design a laboratory experiment in which incomplete information about probabilities is generated in a naturalistic way from the perspective of decision makers, but where the experimenter has complete information. Specifically, we use virtual simulations of property that is at risk of destruction from simulated wild fires. Using direct belief elicitation mechanisms we find that subjective beliefs over high and low risk scenarios underestimate the shift. Thus, predictions of voluntary self-protection activities based on such data would estimate a suboptimal willingness to invest. However, when offering subjects’ self-protection opportunities, their choices indicate that they over-estimate the risk reducing effects and would in fact be willing to pay more than if they knew the objective probabilities. These findings have direct implications for the normative evaluation of risk management policies when risk perception is subjective

Use Case Modeling and Refinement : A Quality-Based Approach

noten this paper, we propose a quality-based use case refinement approach. It consists of a step by step refinement process that combines quality metrics with use case transformation rules. We propose several quality metrics, based on complexity concepts, aimed at measuring the complexity of use cases. Starting from an initial use case, we apply successively a set of transformation rules and measure the resulting use case based on the quality metrics. Our approach is embedded in a general framework allowing us to guide software designers by the mean of quality metrics

Firstnustarobservations of mrk 501 within a radio to tev multi-instrument campaign

We report on simultaneous broadband observations of the TeV-emitting blazar Markarian 501 between 2013 April 1 and August 10, including the first detailed characterization of the synchrotron peak with Swift and NuSTAR. During the campaign, the nearby BL Lac object was observed in both a quiescent and an elevated state. The broadband campaign includes observations with NuSTAR, MAGIC, VERITAS, the Fermi Large Area Telescope, Swift X-ray Telescope and UV Optical Telescope, various ground-based optical instruments, including the GASP-WEBT program, as well as radio observations by OVRO, Metsahovi, and the F-Gamma consortium. Some of the MAGIC observations were affected by a sand layer from the Saharan desert, and had to be corrected using event-by-event corrections derived with a Light Detection and Ranging (LIDAR) facility. This is the first time that LIDAR information is used to produce a physics result with Cherenkov Telescope data taken during adverse atmospheric conditions, and hence sets a precedent for the current and future ground-based gamma-ray instruments. The NuSTAR instrument provides unprecedented sensitivity in hard X-rays, showing the source to display a spectral energy distribution (SED) between 3 and 79 keV consistent with a log-parabolic spectrum and hard X-ray variability on hour timescales. None (of the four extended NuSTAR observations) show evidence of the onset of inverse-Compton emission at hard X-ray energies. We apply a single-zone equilibrium synchrotron self-Compton (SSC) model to five simultaneous broadband SEDs. We find that the SSC model can reproduce the observed broadband states through a decrease in the magnetic field strength coinciding with an increase in the luminosity and hardness of the relativistic leptons responsible for the high-energy emission