A specific type of buried defect in lamellar phase diblock copolymer was studied by experiments and simulations using self-consistent field theory (SCFT). The defects had 3-dimensional structures and created hexagonally arranged holes. They existed not only on the substrate with the guide structures but in fingerprints. The simulation results suggested that one of the causes of the defects is mismatch of the surface affinity of the neutral layer.

This paper introduces a fabrication method to achieve sub-15 nm line-and-space (L/S) patterns by combining grapho- and chemo-epitaxy using poly(styrene-block-methyl methacrylate) copolymer (PS-b-PMMA). The fabrication method is simple, since it eliminates photoresist stripping and also does not require any special materials to form pinning patterns. In this process, the ridges formed on spin-on-glass (SOG) surface work as physical guides and the photoresists on them are utilized as a pinning layer. Fine PS-b-PMMA L/S patterns were obtained in sufficient critical dimension (CD) range of the guide patterns that corresponded to the 15% dose margin using ArF immersion lithography. 3-dimensional grid defects were found to be the origin of the short defects. The half-pitch (hp) 15 nm L/S patterns were transferred successfully to SOG/spin-on-carbon (SOC) stacked substrate.

We also describe fabrication of sub-10 nm L/S patterns using a high-chi block copolymer (BCP).

We present results of astrometric observations of S269 H2O maser performed with VERA (VLBI Exploration of Radio Astrometry). We have monitored the positions of S269 H2O masers for 1 year and successfully detected its parallax to be 189±8 micro-arcsecond. This corresponds to a source distance of 5.28+0.24−0.22 kpc, and is the smallest parallax (and thus the largest distance) that has ever been measured by means of annual parallax. Proper motions of S269 H2O maser were also measured and used to determine the Galactic rotation velocity at the position of S269. Our measurements show that the Galactic rotation velocity at S269 is the same to that at the Sun within 3%, indicating that the Galactic rotation curve is flat out to R~13 kpc.

We have carried out multi-epoch VLBI observations of the H2O maser sources associated with young stellar objects (YSOs) in nearby molecular clouds with VERA (VLBI Exploration of Radio Astrometry), which is a newly constructed VLBI network in Japan (Kobayashi et al. 2003). The main goal of our study is to measure the absolute proper motions and distances to nearby molecular clouds within 1 kpc from the Sun, to reveal their 3-dimensional structures and dynamical properties. Using the VERA dual-beam receiving system (Honma et al. 2003), we have carried out phase-referencing VLBI observations and measured annual parallaxes and absolute proper motions of the H2O maser features with respect to the extragalactic radio sources. We have successfully detected the annual parallax of one of the H2O maser features in Orion KL to be 2.29±0.10 mas, corresponding to the distance of 437±19 pc from the Sun (Hirota et al. 2007). In addition, the annual parallax of SVS13 in NGC 1333 is also determined to be4.10±0.17 mas, corresponding to the distance of 244±10 pc from the Sun, although the life time of the maser features are only 6 months. The absolute proper motions of the H2O maser features associated with Orion KL and NGC 1333 are derived, possibly indicating the outflow motions from the YSOs as well as the systemic motions of the powering sources.

We are conducting a survey of the CO J=2-1 line emission in the southern Milky Way (the Tokyo-Onsala-ESO-Calán Galactic CO survey), using the 60-cm radio telescope (VST2) in La Silla, Chile. It is combined with the northern survey made with the identical telescope (VST1) at Nobeyama (e.g., Sakamoto et al. 1995), and is directly comparable with the Columbia survey of the CO J=1-0 emission (e.g., Dame et al. 1987).

Surely the most striking radio feature in the Galactic center may be a sheaf of straight vertical filaments (VFs, e.g., Yusef-Zadeh, Morris, & Chance 1984) of the radio arc. The VFs are believed to be the manifestations of strong magnetic field lines (≥1mG) which have been illuminated by some local relativistic particle source.

Molecular clouds in the Galactic center region are characterised by their large velocity widths and physical conditions which differ from clouds in the Galactic disk (e.g., Morris 1996). These clouds may not be gravitationally bound, but in equilibrium with the high external pressure in the Galactic bulge (Spergel & Blitz 1992, Oka et al. 1997a).

As a key program of the 45-m telescope at Nobeyama Radio Observatory, we have made high-resolution CO images of the Galactic center region with the 2×2 focal plane array receiver. The data consist of 44,000 12CO and 13,000 13CO spectra taken with 16″ beams spaced by 34″. The 12CO image covers roughly −1.5° ≤ l ≤ +3.4° and −0.6° ≤ b ≤ +0.6° (Oka et al. 1997b)