3,505 research outputs found
Allereinfachste Sätze. Kleine Narratologie der zeitgenössischen japanischen Literatur
This article explores characteristic narrational contents, styles and structures of recent Japanese literature. Provided that narrational concepts of Heisei Literature have hardly been explored, I will argue that after Murakami Haruki was first published in the early 1980s, and with the paradigm shift from junbungaku to "J-Bungaku" in the late 1990s, Heisei Literature has consistently produced “superflat narratives”. An example for a superflat narration is Kawakami Hiromi’s “Furudōgu Nakano shōten” , translated into German in 2009. Kawakami’s text offers narrational flatness to a global readership that is indulging in the pleasures of the moratorium culture of contemporary Japan; the German version offers yet another aspect of narrational pleasures: the ethnolect “J-Deutsch” (J-German)
Beyond the Brim of the Hat: Kinematics of Globular Clusters out to Large Radius in the Sombrero Galaxy
We have obtained radial velocity measurements for 51 new globular clusters
around the Sombrero galaxy. These measurements were obtained using
spectroscopic observations from the AAOmega spectrograph on the
Anglo-Australian Telescope and the Hydra spectrograph at WIYN. Combined with
our own past measurements and velocity measurements obtained from the
literature we have constructed a large database of radial velocities that
contains a total of 360 confirmed globular clusters. Previous studies' analyses
of the kinematics and mass profile of the Sombrero globular cluster system have
been constrained to the inner ~9' (~24 kpc or ~5 effective radii), but our new
measurements have increased the radial coverage of the data, allowing us to
determine the kinematic properties of M104 out to ~15' (~41 kpc or ~9 effective
radii). We use our set of radial velocities to study the GC system kinematics
and to determine the mass profile and V-band mass-to-light profile of the
galaxy. We find that the V-band mass-to-light ratio increases from 4.5 at the
center to a value of 20.9 at 41 kpc (~9 effective radii or 15'), which implies
that the dark matter halo extends to the edge of our available data set. We
compare our mass profile at 20 kpc (~4 effective radii or ~7.4') to the mass
computed from x-ray data and find good agreement. We also use our data to look
for rotation in the globular cluster system as a whole, as well as in the red
and blue subpopulations. We find no evidence for significant rotation in any of
these samples.Comment: Accepted for publication in the Astronomical Journal; 23 pages, 14
figures, and 2 table
The Candidate Intermediate-Mass Black Hole in the Globular Cluster M54
Ibata et al. reported evidence for density and kinematic cusps in the
Galactic globular cluster M54, possibly due to the presence of a 9400
solar-mass black hole. Radiative signatures of accretion onto M54's candidate
intermediate-mass black hole (IMBH) could bolster the case for its existence.
Analysis of new Chandra and recent Hubble Space Telescope astrometry rules out
the X-ray counterpart to the candidate IMBH suggested by Ibata et al. If an
IMBH exists in M54, then it has an Eddington ratio of L(0.3-8 keV) / L(Edd) <
1.4 x 10^(-10), more similar to that of the candidate IMBH in M15 than that in
G1. From new imaging with the NRAO Very Large Array, the luminosity of the
candidate IMBH is L(8.5 GHz) < 3.6 x 10^29 ergs/s (3 sigma). Two background
active galaxies discovered toward M54 could serve as probes of its intracluster
medium.Comment: 4 pages; 2 figures; emulateapj.cls; to appear in A
MRK 1216 & NGC 1277 - An orbit-based dynamical analysis of compact, high velocity dispersion galaxies
We present a dynamical analysis to infer the structural parameters and
properties of the two nearby, compact, high velocity dispersion galaxies
MRK1216 & NGC1277. Combining deep HST imaging, wide-field IFU stellar
kinematics, and complementary long-slit spectroscopic data out to 3 R_e, we
construct orbit-based models to constrain their black hole masses, dark matter
content and stellar mass-to-light ratios. We obtain a black hole mass of
log(Mbh/Msun) = 10.1(+0.1/-0.2) for NGC1277 and an upper limit of log(Mbh/Msun)
= 10.0 for MRK1216, within 99.7 per cent confidence. The stellar mass-to-light
ratios span a range of Upsilon_V = 6.5(+1.5/-1.5) in NGC1277 and Upsilon_H =
1.8(+0.5/-0.8) in MRK1216 and are in good agreement with SSP models of a single
power-law Salpeter IMF. Even though our models do not place strong constraints
on the dark halo parameters, they suggest that dark matter is a necessary
ingredient in MRK1216, with a dark matter contribution of 22(+30/-20) per cent
to the total mass budget within 1 R_e. NGC1277, on the other hand, can be
reproduced without the need for a dark halo, and a maximal dark matter fraction
of 13 per cent within the same radial extent. In addition, we investigate the
orbital structures of both galaxies, which are rotationally supported and
consistent with photometric multi-S\'ersic decompositions, indicating that
these compact objects do not host classical, non-rotating bulges formed during
recent (z <= 2) dissipative events or through violent relaxation. Finally, both
MRK 1216 and NGC 1277 are anisotropic, with a global anisotropy parameter delta
of 0.33 and 0.58, respectively. While MRK 1216 follows the trend of
fast-rotating, oblate galaxies with a flattened velocity dispersion tensor in
the meridional plane of the order of beta_z = delta, NGC 1277 is highly
tangentially anisotropic and seems to belong kinematically to a distinct class
of objects.Comment: 27 pages, 15 figures and 4 tables. Accepted for publication in MNRA
The Black Hole in the Compact, High-dispersion Galaxy NGC 1271
Located in the Perseus cluster, NGC 1271 is an early-type galaxy with a small
effective radius of 2.2 kpc and a large stellar velocity dispersion of 276 km/s
for its K-band luminosity of 8.9x10^{10} L_sun. We present a mass measurement
for the black hole in this compact, high-dispersion galaxy using observations
from the integral field spectrograph NIFS on the Gemini North telescope
assisted by laser guide star adaptive optics, large-scale integral field unit
observations with PPAK at the Calar Alto Observatory, and Hubble Space
Telescope WFC3 imaging observations. We are able to map out the stellar
kinematics on small spatial scales, within the black hole sphere of influence,
and on large scales that extend out to four times the galaxy's effective
radius. We find that the galaxy is rapidly rotating and exhibits a sharp rise
in the velocity dispersion. Through the use of orbit-based stellar dynamical
models, we determine that the black hole has a mass of (3.0^{+1.0}_{-1.1}) x
10^9 M_sun and the H-band stellar mass-to-light ratio is 1.40^{+0.13}_{-0.11}
M_sun/L_sun (1-sigma uncertainties). NGC 1271 occupies the sparsely-populated
upper end of the black hole mass distribution, but is very different from the
Brightest Cluster Galaxies (BCGs) and giant elliptical galaxies that are
expected to host the most massive black holes. Interestingly, the black hole
mass is an order of magnitude larger than expectations based on the galaxy's
bulge luminosity, but is consistent with the mass predicted using the galaxy's
bulge stellar velocity dispersion. More compact, high-dispersion galaxies need
to be studied using high spatial resolution observations to securely determine
black hole masses, as there could be systematic differences in the black hole
scaling relations between these types of galaxies and the BCGs/giant
ellipticals, thereby implying different pathways for black hole and galaxy
growth.Comment: accepted for publication in Ap
Re-evaluating the role of natural killer cells in innate resistance to herpes simplex virus type 1
BACKGROUND: Interferon-γ acts to multiply the potency with which innate interferons (α/β) suppress herpes simplex virus type 1 (HSV-1) replication. Recent evidence suggests that this interaction is functionally relevant in host defense against HSV-1. However, it is not clear which WBCs of the innate immune system, if any, limit HSV-1 spread in an IFN-γ dependent manner. The current study was initiated to determine if natural killer (NK) cells provide innate resistance to HSV-1 infection, and if so to determine if this resistance is IFN-γ-dependent. RESULTS: Lymphocyte-deficient scid or rag2(-/- )mice were used to test four predictions of the central hypothesis, and thus determine if innate resistance to HSV-1 is dependent on 1. NK cell cytotoxicity, 2. NK cells, 3. WBCs, or 4. the IFN-activated transcription factor, Stat 1. Loss of NK cell cytotoxic function or depletion of NK cells had no effect on the progression of HSV-1 infection in scid mice. In contrast, viral spread and pathogenesis developed much more rapidly in scid mice depleted of WBCs. Likewise, loss of Stat 1 function profoundly impaired the innate resistance of rag2(-/- )mice to HSV-1. CONCLUSION: Lymphocyte-deficient mice possess a very tangible innate resistance to HSV-1 infection, but this resistance is not dependent upon NK cells
DYNAMICS OF THE GALACTIC GLOBULAR CLUSTER NGC 3201
B,V CCD frames have been used to derive surface brightness profiles for NGC
3201 out to ~18 arcmin. A total of 857 radial velocities with median precision
~1 km/s for 399 member giants have been used to trace the velocity dispersion
profile out to 32' (the approximate tidal radius from fits of single-mass,
isotropic King-Michie models to the cluster surface brightness profiles). The
median difference in radial velocity for stars on either side of an imaginary
axis moved through the cluster in 1 degree steps shows a significant maximum
amplitude of 1.22+/-0.25 km/s. We discuss possible explanations of this result,
including: (1) cluster rotation; (2) preferential stripping of stars on
prograde orbits near the limiting radius; (3) the projection of the cluster
space velocity onto the plane of the sky and (4) a slight drift in the velocity
zero point. It is difficult to identify the primary cause of the observed
velocity field structure unambiguously, and we suspect that all of the above
processes may play a role. The B,V surface brightness profiles and radial
velocities have been modeled with single- & multi-mass King-Michie models and
nonparametric techniques. The density and M/L profiles show good agreement over
1.5<R<10 pc, and both approaches suggest a steady rise in M/L with distance
from the cluster center. Due to the low cluster luminosity, we are unable to
place useful constraints on the anisotropy of the velocity dispersion profile,
though the global mass-to-light ratio is well-constrained by the models as ~2.0
+/-0.2 for the multi-mass and nonparametric models, compared to ~ 1.65 +/-0.15
for models having equal-mass stars. Our best-fit, multi-mass models have mass
function slopes of x~0.75 +/-0.25, consistent with findings that mass function
depends on the position relative to the potential of the Galaxy.Comment: uuencoded compressed Postscript, 59 pages including 10 figures. Also
available at http://www.dao.nrc.ca/DAO/SCIENCE/science.htm
The Magnitude-Size Relation of Galaxies out to z ~ 1
As part of the Deep Extragalactic Evolutionary Probe (DEEP) survey, a sample
of 190 field galaxies (I_{814} <= 23.5) in the ``Groth Survey Strip'' has been
used to analyze the magnitude-size relation over the range 0.1 < z < 1.1. The
survey is statistically complete to this magnitude limit. All galaxies have
photometric structural parameters, including bulge fractions (B/T), from Hubble
Space Telescope images, and spectroscopic redshifts from the Keck Telescope.
The analysis includes a determination of the survey selection function in the
magnitude-size plane as a function of redshift, which mainly drops faint
galaxies at large distances. Our results suggest that selection effects play a
very important role. A first analysis treats disk-dominated galaxies with B/T <
0.5. If selection effects are ignored, the mean disk surface brightness
(averaged over all galaxies) increases by ~1.3 mag from z = 0.1 to 0.9.
However, most of this change is plausibly due to comparing low luminosity
galaxies in nearby redshift bins to high luminosity galaxies in distant bins.
If this effect is allowed for, no discernible evolution remains in the disk
surface brightness of bright (M_B < -19) disk-dominated galaxies. A second
analysis treats all galaxies by substituting half-light radius for disk scale
length, with similar conclusions. Indeed, at all redshifts, the bulk of
galaxies is consistent with the magnitude-size envelope of local galaxies,
i.e., with little or no evolution in surface brightness. In the two highest
redshift bins (z > 0.7), a handful of luminous, high surface brightness
galaxies appears that occupies a region of the magnitude-size plane rarely
populated by local galaxies. Their wide range of colors and bulge fractions
points to a variety of possible origins.Comment: 19 pages, 12 figures. Accepted for publication in the Astrophysical
Journa
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