A Bayesian analysis of extrasolar planet data for HD 208487

Precision radial velocity data for HD 208487 has been re-analyzed using a new Bayesian multi-planet Kepler periodogram. The periodgram employs a parallel tempering Markov chain Monte Carlo algorithm with a novel statistical control system. We confirm the previously reported orbit (Tinney et al. 2005) of 130 days. In addition, we conclude there is strong evidence for a second planet with a period of 998 -62 +57 days, an eccentricity of 0.19 -0.18 +0.05, and an M sin i = 0.46 -0.13 +0.05 of Jupiter's mass.Comment: For publication in ``Bayesian Inference and Maximum Entropy Methods'', San Jose 2005, K. H. Knuth, A. E. Abbas, R. D. Morris, J. P. Castle (eds.), AIP Conference Proceedin

A Bayesian periodogram finds evidence for three planets in HD 11964

A Bayesian multi-planet Kepler periodogram has been developed for the analysis of precision radial velocity data (Gregory 2005b and 2007). The periodogram employs a parallel tempering Markov chain Monte Carlo algorithm. The HD 11964 data (Butler et al. 2006) has been re-analyzed using 1, 2, 3 and 4 planet models. Assuming that all the models are equally probable a priori, the three planet model is found to be >= 600 times more probable than the next most probable model which is a two planet model. The most probable model exhibits three periods of 38.02+0.06-0.05, 360+-4 and 1924+44-43 d, and eccentricities of 0.22+0.11-0.22, 0.63+0.34-0.17 and 0.05+0.03-0.05, respectively. Assuming the three signals (each one consistent with a Keplerian orbit) are caused by planets, the corresponding limits on planetary mass (M sin i) and semi-major axis are 0.090+0.15-0.14 M_J, 0.253+-0.009 au, 0.21+0.06-0.07 M_J, 1.13+-0.04 au, 0.77+-0.08 M_J, 3.46+-0.13 au, respectively. The small difference (1.3 sigma) between the 360 day period and one year suggests that it might be worth investigating the barycentric correction for the HD 11964 data

Cruise Report 69-S-6: Bottomfish Program

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A pentagonal surface patch for computer-aided geometric design

A vector valued interpolation scheme for a pentagon is described which is compatible with surface patches which have a rectangular domain of definition. Such a scheme could be useful in computer- aided geometric design problems, where a pentagonal patch occurs within a rectangular patch framework

Use of the Terminal Area Simulation System (TASS) to study microburst wind shears

Ground-based and airborne Doppler radar and LIDAR systems are being designed to alert pilots when a hazardous windshear is present. A key element in this design effort is understanding the microburst itself. This is accomplished by means of the TASS model which was developed for NASA by Proctor (1987a,b). The time-dependent TASS model has two vesions: a two-demensional high resolution axisymmetric model, and a three-demensional model. The model includes a sophisticated parameterization of cloud microphysics and a friction layer, both of which are essential to a realistic simulation of the microburst phenomenon. The TASS model has been successfully tested on well-observed convective events