Cavity cooling of an optically trapped nanoparticle

We study the cooling of a dielectric nanoscale particle trapped in an optical cavity. We derive the frictional force for motion in the cavity field, and show that the cooling rate is proportional to the square of oscillation amplitude and frequency. Both the radial and axial centre-of-mass motion of the trapped particle, which are coupled by the cavity field, are cooled. This motion is analogous to two coupled but damped pendulums. Our simulations show that the nanosphere can be cooled to 1/e of its initial momentum over time scales of hundredths of milliseconds.Comment: 11 page

Transition from inspiral to plunge in precessing binaries of spinning black holes

We investigate the non-adiabatic dynamics of spinning black hole binaries by using an analytical Hamiltonian completed with a radiation-reaction force, containing spin couplings, which matches the known rates of energy and angular momentum losses on quasi-circular orbits. We consider both a straightforward post-Newtonian-expanded Hamiltonian (including spin-dependent terms), and a version of the resummed post-Newtonian Hamiltonian defined by the Effective One-Body approach. We focus on the influence of spin terms onto the dynamics and waveforms. We evaluate the energy and angular momentum released during the final stage of inspiral and plunge. For an equal-mass binary the energy released between 40Hz and the frequency beyond which our analytical treatment becomes unreliable is found to be, when using the more reliable Effective One-Body dynamics: 0.6% M for anti-aligned maximally spinning black holes, 5% M for aligned maximally spinning black hole, and 1.8% M for non-spinning configurations. In confirmation of previous results, we find that, for all binaries considered, the dimensionless rotation parameter J/E^2 is always smaller than unity at the end of the inspiral, so that a Kerr black hole can form right after the inspiral phase. By matching a quasi-normal mode ringdown to the last reliable stages of the plunge, we construct complete waveforms approximately describing the gravitational wave signal emitted by the entire process of coalescence of precessing binaries of spinning black holes.Comment: 31 pages, 7 tables, and 13 figure

Post-Newtonian gravitational radiation and equations of motion via direct integration of the relaxed Einstein equations. III. Radiation reaction for binary systems with spinning bodies

Using post-Newtonian equations of motion for fluid bodies that include radiation-reaction terms at 2.5 and 3.5 post-Newtonian (PN) order (O[(v/c)^5] and O[(v/c)^7] beyond Newtonian order), we derive the equations of motion for binary systems with spinning bodies. In particular we determine the effects of radiation-reaction coupled to spin-orbit effects on the two-body equations of motion, and on the evolution of the spins. For a suitable definition of spin, we reproduce the standard equations of motion and spin-precession at the first post-Newtonian order. At 3.5PN order, we determine the spin-orbit induced reaction effects on the orbital motion, but we find that radiation damping has no effect on either the magnitude or the direction of the spins. Using the equations of motion, we find that the loss of total energy and total angular momentum induced by spin-orbit effects precisely balances the radiative flux of those quantities calculated by Kidder et al. The equations of motion may be useful for evolving inspiraling orbits of compact spinning binaries.Comment: 19 pages, small corrections, equivalent to published versio

Implementation of a local principal curves algorithm for neutrino interaction reconstruction in a liquid argon volume

A local principal curve algorithm has been implemented in three dimensions for automated track and shower reconstruction of neutrino interactions in a liquid argon time projection chamber. We present details of the algorithm and characterise its performance on simulated data sets.Comment: 14 pages, 17 figures; typing correction to Eq 5, the definition of the local covariance matri

Distributed utterances

I propose an apparatus for handling intrasentential change in context. The standard approach has problems with sentences with multiple occurrences of the same demonstrative or indexical. My proposal involves the idea that contexts can be complex. Complex contexts are built out of (“simple”) Kaplanian contexts by ordered n-tupling. With these we can revise the clauses of Kaplan’s Logic of Demonstratives so that each part of a sentence is taken in a different component of a complex context. I consider other applications of the framework: to agentially distributed utterances (ones made partly by one speaker and partly by another); to an account of scare-quoting; and to an account of a binding-like phenomenon that avoids what Kit Fine calls “the antinomy of the variable.

Phosphorus Nutrition on Leaching Sands.

The excessive amounts of nutrients entering the Peel-Harvey Estuarine system have resulted in a marked increase in the abundance of algal species .within the estuary and reduced production on the sandy coastal soils of the catchment from which the nutrients are being leached. Recent stream samplings by D.C.E have shown that the deep grey Bassendean sands may be contributing up to 40 per cent of the total P loading in the Harvey River. Agriculture Department trials around Albany on similar sands have shown that up to 80 per cent of the bicarb extractable P may be lost after only 150 mm of rain. Phosphorus rundown trials. 82HA14, 82HA15, 82HA16, 82HA17, 82HA18. Soil test calibration curve trials. 82HA20, 82HA21, 82HA22, 82HA23, 82HA24, 82HA25, 82HA26, 82HA27, 82HA28, 82HA29, 82HA30. P sources x rates x times of application trials. 82HA31, 82HA32. P sources leaching trials. 82HA33, same site as 82HA31, 82HA34, same site as 82HA32. Lime rates with + P. 82HA36, 82HA37, 82HA38, Old land same site as 82HA28. Overall summary. The reverted superphosphates are at least as good as normal superphosphate as far as pasture yield and P uptake are concerned, however bicarb P results indicate considerably less leaching. The very insoluble phosphate areas do not leach to any degree but are less efficient than superphosphate in pasture nutrition. The performance of these less leachable sources is expected to improve relative to superphosphate in subsequent years. The two leaching trials show that there is little difference in P leaching on new and old land sites, however the build-up of organic material on old land appears to have a marked effect on Potassium retention. In 1983 all treatments in the soil test calibration curve trials should have different residual values of P and splitting each plot into untreated and adequately supplied halves should give many points for the soil test calibration curves. From the three trials reported here it would appear that there is no interaction between P nutrition and added lime, however improved pasture management on these trials in 1983 should give more data

Validation of magnetophonon spectroscopy as a tool for analyzing hot-electron effects in devices

It is shown that very high precision hot-electron magnetophonon experiments made on n+n−n+-GaAs sandwich device structures which are customized for magnetoresistance measurements can be very accurately modeled by a new Monte Carlo technique. The latter takes account of the Landau quantization and device architecture as well as material parameters. It is proposed that this combination of experiment and modeling yields a quantitative tool for the direct analysis of spatially localized very nonequilibrium electron distributions in small devices and low dimensional structures