339 research outputs found
Effect of dust size and structure on scattered light images of protoplanetary discs
We study scattered light properties of protoplanetary discs at near-infrared
wavelengths for various dust size and structure by performing radiative
transfer simulations. We show that different dust structures might be probed by
measuring disk polarisation fraction as long as the dust radius is larger than
the wavelength. When the radius is larger than the wavelength, disc scattered
light will be highly polarised for highly porous dust aggregates, whereas more
compact dust structure tends to show low polarisation fraction. Next, roles of
monomer radius and fractal dimension for scattered light colours are studied.
We find that, outside the Rayleigh regime, as fractal dimension or monomer
radius increases, colours of the effective albedo at near-infrared wavelengths
vary from blue to red. Our results imply that discs showing grey or slightly
blue colours and high polarisation fraction in near-infrared wavelengths might
be explained by the presence of large porous aggregates containing sub-microns
sized monomers.Comment: Accepted for publication in MNRAS, 18 pages, 19 figure
Clinical significance of expanded Foxp3+ Helios- regulatory T cells in patients with non-small cell lung cancer
博士(医学)福島県立医科大
Finite size effects on kaonic pasta structures
Non-uniform structures of mixed phases at the first-order phase transition to
charged kaon condensation are studied using a density functional theory within
the relativistic mean field model. Including electric field effects and
applying the Gibbs conditions in a proper way, we numerically determine density
profiles of nucleons, electrons and condensed kaons. Importance of charge
screening effects is elucidated and thereby we show that the Maxwell
construction is effectively justified. Surface effect is also studied to figure
out its effect on the density profiles
The shadow knows: using shadows to investigate the structure of the pretransitional disk of HD 100453
We present GPI polarized intensity imagery of HD 100453 in Y-, J-, and K1
bands which reveals an inner gap ( au), an outer disk ( au) with
two prominent spiral arms, and two azimuthally-localized dark features also
present in SPHERE total intensity images (Wagner 2015). SED fitting further
suggests the radial gap extends to au. The narrow, wedge-like shape of the
dark features appears similar to predictions of shadows cast by a inner disk
which is misaligned with respect to the outer disk. Using the Monte Carlo
radiative transfer code HOCHUNCK3D (Whitney 2013), we construct a model of the
disk which allows us to determine its physical properties in more detail. From
the angular separation of the features we measure the difference in inclination
between the disks 45, and their major axes, PA = 140 east
of north for the outer disk and 100for the inner disk. We find an
outer disk inclination of from face-on in broad agreement
with the Wagner 2015 measurement of 34. SPHERE data in J- and H-bands
indicate a reddish disk which points to HD 100453 evolving into a young debris
disk
- …