On the absolute value of the air-fluorescence yield

The absolute value of the air-fluorescence yield is a key parameter for the energy reconstruction of extensive air showers registered by fluorescence telescopes. In previous publications, we reported a detailed Monte Carlo simulation of the air-fluorescence generation that allowed the theoretical evaluation of this parameter. This simulation has been upgraded in the present work. As a result, we determined an updated absolute value of the fluorescence yield of 7.9+-2.0 ph/MeV for the band at 337 nm in dry air at 800 hPa and 293 K, in agreement with experimental values. We have also performed a critical analysis of available absolute measurements of the fluorescence yield with the assistance of our simulation. Corrections have been applied to some measurements to account for a bias in the evaluation of the energy deposition. Possible effects of other experimental aspects have also been discussed. From this analysis, we determined an average fluorescence yield of 7.04+-0.24 ph/MeV at the above conditions.Comment: Submitted to Astroparticle Physic

Comparison of available measurements of the absolute air-fluorescence yield and determination of its global average value

Experimental results of the absolute air-fluorescence yield are given very often in different units (photons/MeV or photons/m) and for different wavelength intervals. In this work we present a comparison of available results normalized to its value in photons/MeV for the 337 nm band at 1013 hPa and 293 K. The conversion of photons/m to photons/MeV requires an accurate determination of the energy deposited by the electrons in the field of view of the experimental set-up. We have calculated the energy deposition for each experiment by means of a detailed Monte Carlo simulation and the results have been compared with those assumed or calculated by the authors. As a result, corrections to the reported fluorescence yields are proposed. These corrections improve the compatibility between measurements in such a way that a reliable average value with uncertainty at the level of 5% is obtained.Comment: 13 pages, 6 figures. To appear in the Proocedings of the International Symposium on the Recent Progress of Ultra-high Energy Cosmic Ray Observations (UHECR2010), Nagoya, Japan, 201

Punishment and Work Law Compliance: Lessons from Chile

Workplace law activists and reformers find it increasingly more difficult to obtain redress for violation of workers’ rights. Some of them are calling for stricter enforcement and tougher penalties to bring employers into compliance. However, after seven and half months of participant observation at the Labor Directorate and the labor courts of Chile, institutions that use punishment as their main tools of enforcement, I am skeptical about the likelihood of success of mere punishment for effective workplace law enforcement and compliance. I am skeptical even though Chile is a country recognized as the Latin American “jaguar” for its successful economy and high respect for the rule of law. I observed that in Chile punishment bred a culture of resistance against workplace law enforcement. Some powerful employers mobilized courts and other government players against the labor inspectorate, the agency in charge of administratively enforcing all laws regarding the workplace, rendering the institution moot. My findings provide further evidence for New Governance, responsive regulation and traditional “Latin” inspection strategies being advocated by some law and policy scholars in the United States and beyond. While most of these scholars do not discard the importance of punishment, they call for more participatory and cooperative regulatory and enforcement processes, the use of persuasive rather than just punitive enforcement orientations, and conciliatory and remedial strategies by the enforcers to obtain better compliance results. In this manner, the Chilean case supports continued experimentation with non-punitive enforcement tools not just in Chile but also in the United States and beyond