682 research outputs found
Entanglement Cost of Antisymmetric States and Additivity of Capacity of Some Quantum Channel
We study the entanglement cost of the states in the contragredient space,
which consists of -dimensional systems. The cost is always ebits when the state is divided into bipartite \C^d \otimes
(\C^d)^{d-2}. Combined with the arguments in \cite{Matsumoto02}, additivity of
channel capacity of some quantum channels is also shown.Comment: revtex 4 pages, no figures, small changes in title and author's
affiliation and some typo are correcte
Entanglement Cost of Three-Level Antisymmetric States
We show that the entanglement cost of the three-dimensional antisymmetric
states is one ebit.Comment: 8page
Ionization Source of a Minor-axis Cloud in the Outer Halo of M82
The M82 `cap' is a gas cloud at a projected radius of 11.6 kpc along the
minor axis of this well known superwind source. The cap has been detected in
optical line emission and X-ray emission and therefore provides an important
probe of the wind energetics. In order to investigate the ionization source of
the cap, we observed it with the Kyoto3DII Fabry-Perot instrument mounted on
the Subaru Telescope. Deep continuum, Ha, [NII]6583/Ha, and [SII]6716,6731/Ha
maps were obtained with sub-arcsecond resolution. The superior spatial
resolution compared to earlier studies reveals a number of bright Ha emitting
clouds within the cap. The emission line widths (< 100 km s^-1 FWHM) and line
ratios in the newly identified knots are most reasonably explained by slow to
moderate shocks velocities (v_shock = 40--80 km s^-1) driven by a fast wind
into dense clouds. The momentum input from the M82 nuclear starburst region is
enough to produce the observed shock. Consequently, earlier claims of
photoionization by the central starburst are ruled out because they cannot
explain the observed fluxes of the densest knots unless the UV escape fraction
is very high (f_esc > 60%), i.e., an order of magnitude higher than observed in
dwarf galaxies to date. Using these results, we discuss the evolutionary
history of the M82 superwind. Future UV/X-ray surveys are expected to confirm
that the temperature of the gas is consistent with our moderate shock model.Comment: 7 pages, 5 figures, 2 tables; Accepted for publication in Ap
Galactic Wind in the Nearby Starburst Galaxy NGC 253 Observed with the Kyoto3DII Fabry-Perot Mode
We have observed the central region of the nearby starburst galaxy NGC 253
with the Kyoto Tridimensional Spectrograph II (Kyoto3DII) Fabry-Perot mode in
order to investigate the properties of its galactic wind. Since this galaxy has
a large inclination, it is easy to observe its galactic wind. We produced the
Ha, [N II]6583, and [S II]6716,6731 images, as well as those line ratio maps.
The [N II]/Ha ratio in the galactic wind region is larger than those in H II
regions in the galactic disk. The [N II]/Ha ratio in the southeastern filament,
a part of the galactic wind, is the largest and reaches about 1.5. These large
[N II]/Ha ratios are explained by shock ionization/excitation. Using the [S
II]/Ha ratio map, we spatially separate the galactic wind region from the
starburst region. The kinetic energy of the galactic wind can be sufficiently
supplied by supernovae in a starburst region in the galactic center. The shape
of the galactic wind and the line ratio maps are non-axisymmetric about the
galactic minor axis, which is also seen in M82. In the [N II]6583/[S
II]6716,6731 map, the positions with large ratios coincide with the positions
of star clusters found in the Hubble Space Telescope (HST) observation. This
means that intense star formation causes strong nitrogen enrichment in these
regions. Our unique data of the line ratio maps including [S II] lines have
demonstrated their effectiveness for clearly distinguishing between shocked gas
regions and starburst regions, determining the extent of galactic wind and its
mass and kinetic energy, and discovering regions with enhanced nitrogen
abundance.Comment: 22 pages, 5 figures, 1 table, accepted for publication in Ap
Visible camera cryostat design and performance for the SuMIRe Prime Focus Spectrograph (PFS)
We describe the design and performance of the SuMIRe Prime Focus Spectrograph
(PFS) visible camera cryostats. SuMIRe PFS is a massively multi-plexed
ground-based spectrograph consisting of four identical spectrograph modules,
each receiving roughly 600 fibers from a 2394 fiber robotic positioner at the
prime focus. Each spectrograph module has three channels covering wavelength
ranges 380~nm -- 640~nm, 640~nm -- 955~nm, and 955~nm -- 1.26~um, with the
dispersed light being imaged in each channel by a f/1.07 vacuum Schmidt camera.
The cameras are very large, having a clear aperture of 300~mm at the entrance
window, and a mass of 280~kg. In this paper we describe the design of the
visible camera cryostats and discuss various aspects of cryostat performance
Mie-resonances, infrared emission and band gap of InN
Mie resonances due to scattering/absorption of light in InN containing
clusters of metallic In may have been erroneously interpreted as the infrared
band gap absorption in tens of papers. Here we show by direct thermally
detected optical absorption measurements that the true band gap of InN is
markedly wider than currently accepted 0.7 eV. Micro-cathodoluminescence
studies complemented by imaging of metallic In have shown that bright infrared
emission at 0.7-0.8 eV arises from In aggregates, and is likely associated with
surface states at the metal/InN interfaces.Comment: 4 pages, 5 figures, submitted to PR
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