906 research outputs found
Justice Bushrod Washington and the Age of Discovery in American Law
古代日本語の船舶の名称やそれに由来する語彙には、日本語一視点のみでは正確に理解できないものがある。これらの単語には、適切な海の民の視点、具体的には、彼らが用いたであろう言語や文化についての知識を持てば正確に理解できるものがある。茂在寅男氏は、『記』『紀』の中に古代ポリネシア語が多く混じっている、と述べ、井上夢間氏は、「枯野」等の言葉とカヌーとの関係について、ハワイ語を用いて簡潔に説明したが、その知見は、言語面からの研究に突破口を開くものであった。小論では、「天アマ」は、ポリネシア語の「ama」を漢字で書き記したものであり、全称を「天鳥船、天鴿船、天磐船」という船舶の略称であること、「鳥を舶載する、アウトリガー・フロート付き外洋航海船」を意味すること、などを解明することができた。古代の日本語の問題を考えたり、古典を読み解くのに、中国語やポリネシア語等の外国語の知識や、船舶・航海の知識が役に立つという認識は、やがて常識となるのではないか。天鳥船/天鴿船/天磐船天岩戸天の原天離る天飛ぶ
The Higgs field and the ultraviolet behaviour of the vortex operator in 2+1 dimensions
We calculate the change in the ultraviolet behaviour of the vortex operator
due to the presence of dynamical Higgs field in both 2+1 dimensional QED and
the 2+1 dimensional Georgi-Glashow model. We find that in the QED case the
presence of the Higgs field leads at the one loop level to power like
correction to the propagator of the vortex operator. On the other hand, in the
Georgi-Glashow model, the adjoint Higgs at one loop has no affect on the vortex
propagator. Thus, as long as the mass of the Higgs field is much larger than
the gauge coupling constant, the ultraviolet behaviour of the vortex operator
in the Georgi-Glashow model is independent of the Higgs mass.Comment: 14 page
A julid milliped in Chilean Patagonia, and a compilation of ordinal representatives in South America and associated islands (Diplopoda: Julida)
An adventive female Julidae (Julida), discovered in a moist, grassy depression in the Peninsula de Brunswick south of Punta Arenas, Chile, and assigned to Cylindroiulus Verhoeff, 1894, is the fi rst vouchered milliped from southern Patagonia. The southernmost milliped ever collected in Chile, South America, and the Western Hemisphere, it may also constitute the southernmost in the world as the site is only ~1,176 km (735 mi) northwest of the Antarctic Peninsula. Records are consolidated of the two families, three genera, and fi ve species of this Holarctic order that are known from South America. They are documented from Argentina, Chile, and southern Peru and Brazil; three species are known from the Juan Fernandez Islands
Homogeneous Velocity-Distance Data for Peculiar Velocity Analysis. I. Calibration of Cluster Samples
We have combined five Tully-Fisher (TF) redshift-distance samples for
peculiar velocity analysis: the cluster data of Han, Mould and coworkers
(1991-93, HM) and Willick (1991, W91CL), and the field data of Aaronson et al.
(1992), Willick (1991), Courteau & Faber (1992), and Mathewson et al. (1992),
totaling over 3000 spiral galaxies. We treat the cluster data in this paper,
which is the first of a series; in Paper II we treat the field TF samples.
These data are to be combined with elliptical data (e.g., Faber et al. 1989) to
form the MARK III CATALOG OF GALAXY PECULIAR VELOCITIES, which we will present
in Paper III. The catalog will be used as input for POTENT reconstruction of
velocity and density fields, described in later papers, as well as for
alternative velocity analyses. Our main goal in Papers I & II is to place the
TF data onto a self-consistent system by (i) applying a uniform set of
corrections to the raw observables, (ii) determining the TF slopes and scatters
separately for each sample, and (iii) adjusting the TF zeropoints to ensure
mutually consistent distances. The global zeropoint is set by the HM sample,
chosen because of its depth and uniformity on the sky and its substantial
overlap with each of the other samples. In this paper, we calibrate the
``forward'' and ``inverse'' TF relations for HM and W91CL. We study the
selection criteria for these samples and correct for the resultant statistical
biases. The bias corrections are validated by comparing forward and inverse
cluster distances. We find that many sample clusters are better modeled as
``expanding'' than relaxed, which significantly affects the TF calibrations.
Proper corrections for internal extinction are derived self-consistently from
the data.Comment: 42 Pages, uuencoded PostScript. Submitted to ApJ. 22 Figures not
included, can be obtained via ftp, contact [email protected]
On the Origin of [OII] Emission in Red Sequence and Post-starburst Galaxies
We investigate the emission-line properties of galaxies with red rest-frame
colors using spectra from SDSS DR4. Emission lines are detected in more than
half of the red galaxies. We focus on the relationship between two emission
lines commonly used as star formation rate indicators: Ha 6563 and [OII] 3727.
There is a strong bimodality in [OII]/Ha ratio in the full SDSS sample which
closely corresponds to the bimodality in rest-frame color. Nearly all of the
line-emitting red galaxies have line ratios typical of various types of AGN --
most commonly LINERs, a small fraction of transition objects and, more rarely,
Seyferts. Only ~6% of red galaxies display star-forming line ratios. A straight
line in the [OII]-Ha equivalent width plane separates LINER-like galaxies from
other categories. Quiescent galaxies with no detectable emission lines and
LINER-like galaxies combine to form a single, tight red sequence in
color-magnitude-concentration space. [OII] EWs in LINER- and AGN-like galaxies
can be as large as in star-forming galaxies. Thus, unless objects with
AGN/LINER-like line ratios are excluded, [OII] emission cannot be used directly
as a proxy for star formation rate. Lack of [OII] emission is generally used to
indicate lack of star formation when post-starburst galaxies are selected at
high redshift. Our results imply, however, that these samples have been cut on
AGN properties as well as star formation, and therefore may provide seriously
incomplete sets of post-starburst galaxies. Furthermore, post-starburst
galaxies identifed in SDSS by requiring minimal Ha EW generally exhibit weak
but nonzero line emission with ratios typical of AGNs; few of them show
residual star formation. This suggests that most post-starbursts may harbor
AGNs/LINERs.Comment: 21 pages, 15 figures. v2: Added 4 new figures and updated many;
extended text. No conclusions change. v3: minor modifications and figure
updates to match version accepted by Ap
On the Evolution of the Velocity-Mass-Size Relations of Disk-Dominated Galaxies over the Past 10 Billion Years
We study the evolution of the scaling relations between maximum circular
velocity, stellar mass and optical half-light radius of star-forming
disk-dominated galaxies in the context of LCDM-based galaxy formation models.
Using data from the literature combined with new data from the DEEP2 and AEGIS
surveys we show that there is a consistent observational and theoretical
picture for the evolution of these scaling relations from z\sim 2 to z=0. The
evolution of the observed stellar scaling relations is weaker than that of the
virial scaling relations of dark matter haloes, which can be reproduced, both
qualitatively and quantitatively, with a simple, cosmologically-motivated model
for disk evolution inside growing NFW dark matter haloes. In this model optical
half-light radii are smaller, both at fixed stellar mass and maximum circular
velocity, at higher redshifts. This model also predicts that the scaling
relations between baryonic quantities evolve even more weakly than the
corresponding stellar relations. We emphasize, though, that this weak evolution
does not imply that individual galaxies evolve weakly. On the contrary,
individual galaxies grow strongly in mass, size and velocity, but in such a way
that they move largely along the scaling relations. Finally, recent
observations have claimed surprisingly large sizes for a number of star-forming
disk galaxies at z \sim 2, which has caused some authors to suggest that high
redshift disk galaxies have abnormally high spin parameters. However, we argue
that the disk scale lengths in question have been systematically overestimated
by a factor \sim 2, and that there is an offset of a factor \sim 1.4 between
H\alpha sizes and optical sizes. Taking these effects into account, there is no
indication that star forming galaxies at high redshifts (z\sim 2) have
abnormally high spin parameters.Comment: 19 pages, 10 figures, accepted to MNRAS, minor changes to previous
versio
The DEEP2 Galaxy Redshift Survey: Mean Ages and Metallicities of Red Field Galaxies at z ~ 0.9 from Stacked Keck/DEIMOS Spectra
As part of the DEEP2 galaxy redshift survey, we analyze absorption line
strengths in stacked Keck/DEIMOS spectra of red field galaxies with weak to no
emission lines, at redshifts 0.7 <= z <= 1. Comparison with models of stellar
population synthesis shows that red galaxies at z ~ 0.9 have mean
luminosity-weighted ages of the order of only 1 Gyr and at least solar
metallicities. This result cannot be reconciled with a scenario where all stars
evolved passively after forming at very high z. Rather, a significant fraction
of stars can be no more than 1 Gyr old, which means that star formation
continued to at least z ~ 1.2. Furthermore, a comparison of these distant
galaxies with a local SDSS sample, using stellar populations synthesis models,
shows that the drop in the equivalent width of Hdelta from z ~ 0.9 to 0.1 is
less than predicted by passively evolving models. This admits of two
interpretations: either each individual galaxy experiences continuing low-level
star formation, or the red-sequence galaxy population from z ~ 0.9 to 0.1 is
continually being added to by new galaxies with younger stars.Comment: A few typos were corrected and numbers in Table 1 were revise
The DEEP3 Galaxy Redshift Survey: The Impact of Environment on the Size Evolution of Massive Early-type Galaxies at Intermediate Redshift
Using data drawn from the DEEP2 and DEEP3 Galaxy Redshift Surveys, we
investigate the relationship between the environment and the structure of
galaxies residing on the red sequence at intermediate redshift. Within the
massive (10 < log(M*/Msun) < 11) early-type population at 0.4 < z <1.2, we find
a significant correlation between local galaxy overdensity (or environment) and
galaxy size, such that early-type systems in higher-density regions tend to
have larger effective radii (by ~0.5 kpc or 25% larger) than their counterparts
of equal stellar mass and Sersic index in lower-density environments. This
observed size-density relation is consistent with a model of galaxy formation
in which the evolution of early-type systems at z < 2 is accelerated in
high-density environments such as groups and clusters and in which dry, minor
mergers (versus mechanisms such as quasar feedback) play a central role in the
structural evolution of the massive, early-type galaxy population.Comment: 11 pages, 5 figures, 2 tables; resubmitted to MNRAS after addressing
referee's comments (originally submitted to journal on August 16, 2011
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