Optimization of the wave front of high order harmonics

We present a full optimization of the high harmonics wave front owing to the use of a soft X-ray Hartmann sensor. The sensor was calibrated using a high harmonic source with an accuracy of λ/50 root-mean-square (rms) with λ around 30 nm. We observed a high harmonic wave front of λ/7 rms, which is two times the diffraction-limit, astigmatism being the dominant aberration for every condition of generation. By clipping slightly the unfocused high harmonic beam, it is possible to produce a diffraction-limited beam containing approximately 90% of the incident energy

EDGAR on the internet: The welfare effects of wider information distribution in an experimental market for risky assets

Policies such as the SEC’s Fair Disclosure Rule, and technologies such as SEC EDGAR, aim to disseminate corporate disclosures to a wider audience of investors in risky assets. In this study, we adopt an experimental approach to measure whether this wider disclosure is beneficial to these investors. Price-clearing equilibrium models based on utility maximization and non-revealing and fully-revealing prices predict that in a pure exchange economy, an arbitrary trader would prefer that no investors are informed rather than all are informed; non-revealing theory further predicts that an arbitrary trader would prefer a situation in which all traders are informed rather than half the traders are informed. These predictions can be summarized as “None > All > Halfâ€. A laboratory study was conducted to test these predictions. Where previous studies have largely focused on information dissemination and its effects on equilibrium price and insider profits, we focus instead on traders’ expected utility, as measured by their preferences for markets in which none, half, or all traders are informed. Our experimental result contradicts the prediction and indicates “Half > None > Allâ€, i.e. subjects favor a situation where a random half is informed. The implication is that in addition to testing predictions of price equilibrium, experiments should also be used to verify analytical welfare predictions of expected utility under different policy choices. Copyright Economic Science Association 2006Asymmetric and private information, Financial markets, Information and market efficiency, Information and internet services,

The enactment of risk categories: the role of information systems in organizing and re-organizing risk management practices in the energy industry

This research explores the role of information systems in risk management during a twenty year period when new governance arrangements led to enterprise-wide change in the UK energy markets. We present a longitudinal case study documenting the role of "A-Trade" transaction and risk management software in the adaptation of energy organizations to competitive demands associated with a simultaneous process of privatization and liberalization. During the design, development and implementation of A-Trade, multiple forms of expertise were brought together in what we describe as organizational encounters with risk. The story of "A-Trade" highlights the shift from a traditional engineer-led culture of risk cognition to marketoriented financial risk management. Our findings are that, firstly, that energy transaction and risk management software development provided an important learning ground during periods of paradigmatic change. Secondly, we provide insights into the enactment of risk categories and the challenges associated with establishing an information infrastructure to support risk management