Institutional Choice and Targeted Killing: A Comparative Perspective

For over a decade, the use of targeted killing has been one of the most controversial issues in counterterrorism policy and law. One longstanding debate over this tactic concerns the allocation of decision-making and oversight authority among the branches of government. As attempts to settle this debate through textual and historical sources yield indeterminant answers, scholars tend to examine them through a functionalist prism, asking what institutional structures best serve the interests of national security while ensuring adequate accountability and preventing unnecessary force. This article, retaining that functionalist framing of that issue, will approach the question through a comparative law analysis. Three of the countries most heavily engaged in global counterterrorism—the U.S., the U.K., and Israel—have adopted substantially different approaches for regulating counterterrorism targeting, each according a primary supervisory role to a different governmental actor: the Executive in the U.S., Parliament in the U.K., and the Judiciary in Israel. This article describes, compares, and critically analyzes these approaches. Drawing on comparative institutional analysis theory, it then examines the findings and reaches three main conclusions. First, that in light of the judiciary’s unique structural perspective and expertise, some judicial involvement in developing the legal standard that guides and constrains government action is desirable. Second, that suboptimal decision-making and illegality due to executive bias are more likely to occur where the executive is accountable only to its own internal oversight mechanisms. And third, that in both presidential and parliamentarian systems, legislators do not have and are unlikely to have any sort of meaningful influence on executive behavior in this domain. The article concludes by suggesting a few possible institutional reforms

Spark Model for Pulsar Radiation Modulation Patterns

A non-stationary polar gap model first proposed by Ruderman & Sutherland (1975) is modified and applied to spark-associated pulsar emission at radio wave-lengths. It is argued that under physical and geometrical conditions prevailing above pulsar polar cap, highly non-stationary spark discharges do not occur at random positions. Instead, sparks should tend to operate in well determined preferred regions. At any instant the polar cap is populated as densely as possible with a number of two-dimensional sparks with a characteristic dimension as well as a typical distance between adjacent sparks being about the polar gap height. Our model differs, however, markedly from its original 'hollow cone' version. The key feature is the quasi-central spark driven by pair production process and anchored to the local pole of a sunspot-like surface magnetic field. This fixed spark prevents the motion of other sparks towards the pole, restricting it to slow circumferential drift across the planes of field lines converging at the local pole. We argue that the polar spark constitutes the core pulsar emission, and that the annular rings of drifting sparks contribute to conal components of the pulsar beam. We found that the number of nested cones in the beam of typical pulsar should not excced three; a number also found by Mitra & Deshpande (1999) using a completely different analysis.Comment: 31 pages, 8 figures, accepted by Ap

On factor-free Dyck words with half-integer slope

We study a class of rational Dyck paths with slope (2m+1)/2 corresponding to factor-free Dyck words, as introduced by P. Duchon. We show that, for the slopes considered in this paper, the language of factor-free Dyck words is generated by an auxiliary language that we examine from the algebraic and combinatorial points of view. We provide a lattice path description of this language, and give an explicit enumeration formula in terms of partial Bell polynomials. As a corollary, we obtain new formulas for the number of associated factor-free generalized Dyck words.Comment: 13 pages. To appear in Advances in Applied Mathematic

Frequency dependence of pulsar radiation patterns

We report on new results from simultaneous, dual frequency, single pulse observation of PSR B0329+54 using the Giant Metrewave Radio Telescope. We find that the longitude separation of subpulses at two different frequencies (238 and 612 MHz) is less than that for the corresponding components in the average profile. A similar behaviour has been noticed before in a number of pulsars. We argue that subpulses are emitted within narrow flux tubes of the dipolar field lines and that the mean pulsar beam has a conal structure. In such a model the longitudes of profile components are determined by the intersection of the line of sight trajectory with subpulse-associated emission beams. Thus, we show that the difference in the frequency dependence of subpulse and profile component longitudes is a natural property of the conal model of pulsar emission beam. We support our conclusions by numerical modelling of pulsar emission, using the known parameters for this pulsar, which produce results that agree very well with our dual frequency observations.Comment: 24 pages, 8 figures. Accepted for publication in Ap