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The accurate measurement of extragalactic distances is a central challenge of modern astronomy, being required for any realistic description of the age, geometry and fate of the Universe. The measurement of relative extragalactic distances has become fairly routine, but estimates of absolute distances are rare 1. In the vicinity of the Sun, direct geometric(More)
In the permanently stagnant depths of Green Lake (near Syracuse, N.Y.), sulfide made by bacteria is depleted in heavy sulfur (S(34)), and sulfate is enriched. The fractionation factor, 1.0575, is the greatest yet observed. Isotopic resemblance to salt-dome sulfur deposits is evident, and, like saltdome calcite, the lake's carbon dioxide is depleted in heavy(More)
Electrostatic atomization has been studied to inject charged water droplets into oil in a microchannel reactor system. With a negative DC voltage, Taylor cone was formed and the droplets were injected into oil within 1/30 sec. The injection took place periodically with interval of a few seconds when the DC voltage was maintained. Using water, droplets of(More)
We report a 3σ upper limit of 220 µJy on any 22-GHz continuum emission coincident with the central engine in NGC 4258. If NGC 4258 is powered by an advection-dominated accretion flow, this radio upper limit implies that the inner advection-dominated flow cannot extend significantly beyond ∼ 10 2 Schwarzschild radii.
We have observed the nuclear region of an edge-on spiral galaxy NGC 5793 with VLBI in order to determine the morphology of the central continuum source at 6 and 18 cm and the distribution of OH molecular gas at 18 cm on parsec scales. NGC 5793, with a type 2 Seyfert nucleus, is known to have peculiar H 2 O maser features in its center, indicating the(More)
We present the first 100 pc scale view of the dense molecular gas in the central 1.3 kpc of the type-1 Seyfert NGC 1097, traced by HCN (J = 4–3) and HCO + (J = 4–3) lines afforded with ALMA band 7. This galaxy shows significant HCN enhancement with respect to HCO + and CO in the low-J transitions, which seems to be a common characteristic in AGN(More)
The edge-on galaxy NGC 4565 has been observed in the 12 CO(J = 1 − 0)-line emission using the Nobeyama 45-m telescope with an angular resolution of 15 ′′. We obtained a scan along the major axis for ±5 ′ (±15 kpc) about the galactic center, and some scans perpendicular to the galactic plane. The radial density distribution shows a dense molecular gas ring(More)
We present Atacama Large Millimeter/submillimeter Array (ALMA) Cycle 1 observations of the central kiloparsec region of the luminous type1 Seyfert galaxy NGC 7469 with unprecedented high resolution (0 5 ×0 4 = 165 × 132 pc) at submillimeter wavelengths. Utilizing the widebandwidth of ALMA, we simultaneously obtained HCN(4–3), HCO + (4–3), CS(7–6), and(More)
We made CO and HCN simultaneous observations of lenticular galaxies, NGC 404, NGC 3593 and NGC 4293, and detected HCN emission in NGC 3593 and NGC 4293 as well as CO in all the galaxies. The I HCN /I CO ratios were 0.025 ± 0.006 and 0.066 ± 0.005 in NGC 3593 and NGC4293, respectively, which are comparable to the late-type spiral galaxies. The average of the(More)