On the various origins of close-in extrasolar planets (2009)
Marchi, S., Ortolani, S., Nagasawa, M., Ida, S.
The extrasolar planets (EPs) so far detected are very different to the planets in our own Solar System. Many of them have Jupiter-like masses and close-in orbits (the so-called hot planets, HPs),...
Modification of Angular Velocity by Inhomogeneous MRI Growth in Protoplanetary Disks (2008)
Kato, M. T., Nakamura, K., Tandokoro, R., Fujimoto, M., Ida, S.
We have investigated evolution of magneto-rotational instability (MRI) in protoplanetary disks that have radially non-uniform magnetic field such that stable and unstable regions coexist initially,...
Schlaufman, Kevin C., Lin, D. N. C., Ida, S.
Existing exoplanet radial velocity surveys are complete in the planetary mass-semimajor axis (Mp-a) plane over the range 0.1 AU < a < 2.0 AU where Mp >~ 100 M_Earth. We marginalize over mass in this...
Nagasawa, M., Ida, S., Bessho, T.
We have investigated the formation of close-in extrasolar giant planets through a coupling effect of mutual scattering, Kozai mechanism, and tidal circularization, by orbital integrations. We have...
On gas drag in a circular binary system (2007)
Ciecielag, P., Ida, S., Gawryszczak, A., Burkert, A.
We investigate both analytically and numerically the motion of massless particles orbiting primary star in a close circular binary system with particular focus on the gas drag effects. These are the...
On the Origin of HD149026b (2006)
Ikoma, M., Guillot, T., Genda, H., Takayuki, T., Ida, S.
The high density of the close-in extrasolar planet HD149026b suggests the presence of a huge core in the planet, which challenges planet formation theory. We first derive constraints on the amount of...
The N2K consortium. III. short-period planets orbiting HD 149143 and HD 109749 (2006)
Fischer, D. A., Laughlin, G., Marcy, G. W., Butler, R. P., Vogt, S. S., Johnson, J. A., ...
(c) 2006: The American Astronomical Society
The N2K consortium. III. short-period planets orbiting HD 149143 and HD 109749 (2006)
Fischer, D. A., Laughlin, G., Marcy, G. W., Butler, R. P., Vogt, S. S., Johnson, J. A., ...
(c) 2006: The American Astronomical Society
The N2K Consortium. II. A Transiting Hot Saturn Around HD 149026 With a Large Dense Core (2005)
Sato, B., Fischer, D. A., Henry, G. W., Laughlin, G., Butler, R. P., Marcy, G. W., ...
Doppler measurements from Subaru and Keck have revealed radial velocity variations in the V=8.15, G0IV star HD 149026 consistent with a Saturn-Mass planet in a 2.8766 day orbit. Photometric...
The origin of a recently discovered close-in Neptune-mass planet around GJ436 poses a challenge to the current theories of planet formation. Based on the sequential accretion hypothesis and the...
A Hot Saturn Planet Orbiting HD 88133, from the N2K Consortium (2004)
Fischer, D. A., Laughlin, G., Butler, R. P., Marcy, G. W., Johnson, J., Henry, G., ...
The N2K consortium is carrying out a distributed observing campaign with the Keck, Magellan and Subaru telescopes, as well as the automatic photometric telescopes of Fairborn Observatory, in order to...
The formation and retention of gas giant planets around stars with a range of metallicities (2004)
The apparent dependence of detection frequency of extrasolar planets on the metallicity of their host stars is investigated with Monte Carlo simulations using a deterministic core-accretion planet...
We examine the accretion of cores of giant planets from planetesimals, gas accretion onto the cores, and their orbital migration. We adopt a working model for nascent protostellar disks with a wide...
Nagasawa, M., Lin, D. N. C., Ida, S.
Most extrasolar planets are observed to have eccentricities much larger than those in the solar system. Some of these planets have sibling planets, with comparable masses, orbiting around the same...
We investigate the formation of spatial structure in dense, self-gravitating particle systems such as Saturn's B-ring through local $N$-body simulations to clarify the intrinsic physics based on...
Evolution of the Velocity Dispersion of Self-Gravitating Particles in Disc Potentials (1999)
The ratio of the vertical velocity dispersion to radial one (sigma_z / sigma_R) of self-gravitating bodies in various disc potentials is investigated through two different numerical methods...
Ida, S., Larwood, J. D., Burkert, A.
We have investigated effects of early stellar encounters on a protoplanetary disk (planetesimal disk) and found that they can explain the high eccentricities and inclinations observed in the outer...
Planet formation, orbital evolution and planet-star tidal interaction (1998)
Lin, D. N. C., Papaloizou, J. C. B., Bryden, G., Ida, S., Terquem, C.
We consider several processes operating during the late stages of planet formation that can affect observed orbital elements. Disk-planet interactions, tidal interactions with the central star, long...
Shioda, T, Oka, S, Ida, S, Nokihara, K, Toriyoshi, H, Mori, S, ...
Human immunodeficiency virus type 1 circulates in vivo as a mixture of heterologous populations (quasispecies). We previously analyzed the quasispecies of the third hypervariable region (V3) in the...
Permeability of Nitrobacter agilis to Organic Compounds1
Ida, S. (Cornell University, Ithaca, N.Y.), and M. Alexander. Permeability of Nitrobacter agilis to organic compounds. J. Bacteriol. 90:151–156. 1965.—None of a variety of inorganic ions or...
Shioda, T, Oka, S, Ida, S, Nokihara, K, Toriyoshi, H, Mori, S, ...
Human immunodeficiency virus type 1 circulates in vivo as a mixture of heterologous populations (quasispecies). We previously analyzed the quasispecies of the third hypervariable region (V3) in the...
Permeability of Nitrobacter agilis to Organic Compounds1
Ida, S. (Cornell University, Ithaca, N.Y.), and M. Alexander. Permeability of Nitrobacter agilis to organic compounds. J. Bacteriol. 90:151–156. 1965.—None of a variety of inorganic ions or...
Enhancement of IgE-mediated histamine release from human basophils by immune-specific lymphokines.
Ida, S, Hooks, J J, Siraganian, R P, Notkins, A L
Human leucocytes (basophils) release histamine when exposed to ragweed antigen E or anti-IgE. The present study shows that when leucocytes from BCG-positive donors are first incubated with PPD and...
Kimura, M, Ida, S, Shimada, K, Kanai, Y
(C57BL/6 X DBA/2)F1 mice undergoing the graft-vs-host reaction (GVHR) produce autoantibodies after the injection of DBA/2 lymphoid cells. The anti-nuclear antibodies, including anti-poly (ADP-ribose)...