Tradable Permits with Incomplete Monitoring: Evidence from Santiago’s Particulate Permits Program

I explore the advantages of tradable emission permits over uniform emission standards when the regulator has incomplete information on firms’ emissions and costs of production and abatement (e.g., air pollution in large cities). Because the regulator only observes each firm’s abatement technology but neither its emissions nor its output, there are cases in which standards can lead to lower emissions and, hence, welfare dominate permits. I then empirically examine these issues using evidence from a particulate permits market in Santiago, Chile.asymmetric information, imperfect monitoring, pollution markets, permits

Oscillations of relativistic axisymmetric tori and implications for modelling kHz-QPOs in neutron-star X-ray binaries

We perform a global linear perturbative analysis, and investigate the oscillation properties of relativistic, non-selfgravitating tori orbiting around neutron stars in the slow rotation limit approximation. Extending the work done in Schwarzschild and Kerr backgrounds, we consider the axisymmetric oscillations of vertically integrated tori in the Hartle-Thorne spacetime. The equilibrium models are constructed by selecting a number of different non-Keplerian distributions of specific angular momentum, allowing for disc sizes $L \sim 0.5 - 600$ gravitational radii. Our results, obtained after solving a global eigenvalue problem to compute the xisymmetric $p$-modes, indicate that such oscillation modes could account with most observed lower ($\nu_L$) and upper ($\nu_U$) high frequency quasi-periodic oscillations for Sco X-1, and for some Z sources and Atoll sources with $\nu_L\ gtrsim 500$ Hz. However, when $\nu_L \lesssim 500$ Hz, $p$-modes oscillations do not account for the linear relation $\nu_U = A \nu_L + B$, $B \neq 0$ between the upper and the lower high frequency quasi-periodic oscillations that are observed in neutron star low-mass X-ray binaries.Comment: 8 pages, 4 figures, matches accepted version for publication in MNRA

Stochastic backgrounds of gravitational waves and spherical detectors

The analysis of how a stochastic background of gravitational radiation interacts with a spherical detector is given in detail, which leads to explicit expressions for the system response functions, as well as for the cross-correlation matrix of different readout channels. It is shown that distinctive features of GW induced random detector excitations, relative to locally generated noise, are in practice insufficient to separate the signal from the noise by means of a single sphere, if prior knowledge on the GW spectral density is nil. The situation significantly improves when such previous knowledge is available, due to the omnidirectionality and multimode capacities of a spherical GW antenna.Comment: 19 page

All-sky search algorithms for monochromatic signals in resonant bar GW detector data

In this paper we design and develop several filtering strategies for the analysis of data generated by a resonant bar Gravitational Wave (GW) antenna, with the goal to assess the presence (or absence) in them of long duration monochromatic GW signals, as well as their eventual amplitude and frequency, within the sensitivity band of the detector. Such signals are most likely generated in the fast rotation of slightly asymmetric spinning stars. We shall develop the practical procedures, together with the study of their statistical properties, which will provide us with useful information on each technique's performance. The selection of candidate events will then be established according to threshold-crossing probabilities, based on the Neyman-Pearson criterion. In particular, it will be shown that our approach, based on phase estimation, presents better signal-to-noise ratio than the most common one of pure spectral analysis.Comment: 17 pages, 10 PS figures, psbox, MNRAS TeX, submitted to MNRAS, revised 22-june-1998, full quality figures available compressed at ftp://fismat.ffn.ub.es/pub/papers/gr-qc/fig_9804026.zi

Steady self-diffusion in classical gases

A steady self-diffusion process in a gas of hard spheres at equilibrium is analyzed. The system exhibits a constant gradient of labeled particles. Neither the concentration of these particles nor its gradient are assumed to be small. It is shown that the Boltzmann-Enskog kinetic equation has an exact solution describing the state. The hydrodynamic transport equation for the density of labeled particles is derived, with an explicit expression for the involved self-diffusion transport coefficient. Also an approximated expression for the one-particle distribution function is obtained. The system does not exhibit any kind of rheological effects. The theoretical predictions are compared with numerical simulations using the direct simulation Monte Carlo method and a quite good agreement is found

Uniform self-diffusion in a granular gas

A granular gas composed of inelastic hard spheres or disks in the homogeneous cooling state is considered. Some of the particles are labeled and their number density exhibits a time-independent linear profile along a given direction. As a consequence, there is a uniform flux of labeled particles in that direction. It is shown that the inelastic Boltzmann-Enskog kinetic equation has a solution describing this self-diffusion state. Approximate expressions for the transport equation and the distribution function of labeled particles are derived. The theoretical predictions are compared with simulation results obtained using the direct Monte Carlo method to generate solutions of the kinetic equation. A fairly good agreement is found

Anomalous self-diffusion in a freely evolving granular gas near the shearing instability

The self-diffusion coefficient of a granular gas in the homogeneous cooling state is analyzed near the shearing instability. Using mode-coupling theory, it is shown that the coefficient diverges logarithmically as the instability is approached, due to the coupling of the diffusion process with the shear modes. The divergent behavior, which is peculiar of granular gases and disappears in the elastic limit, does not depend on any other transport coefficient. The theoretical prediction is confirmed by molecular dynamics simulation results for two-dimensional systems