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We report the latest results of 225 GHz atmospheric opacity measurements from two arctic sites; one on high coastal terrain near the Eureka weather station, on Ellesmere Island, Canada, and the other at the Summit Station near the peak of the Greenland icecap. This is a campaign to search for a site to deploy a new telescope for submillimeter Very Long Baseline Interferometry and THz astronomy in the northern hemisphere. Since 2011, we have obtained 3 months of winter data near Eureka, and about one year of data at the Summit Station. The results indicate that these sites offer a highly transparent atmosphere for observations in submillimeter wavelengths. The Summit Station is particularly excellent, and its zenith opacity at 225 GHz is statistically similar to the Atacama Large Milllimeter/submillimeter Array in Chile. In winter, the opacity at the Summit Station is even comparable to that observed at the South Pole., Comment: IAU Symp. 288, in press (4 pages, 3 figures)

We study tunneling processes of Bose-Einstein condensate (BEC) on the real time stochastic approach and reveal some properties of their tunneling time. An important result is that the tunneling time decreases as the repulsive interatomic interaction becomes stronger. Furthermore, the tunneling time in a strong interaction region is not much affected by the potential height and is represented by an almost constant function. We also obtain the other related times such as the hesitating and interaction ones and investigate their dependence on the interaction strength. Finally, we calculate the mean arrival time of BEC wave packet and show the large displacement of its peak position., Comment: 8 page, 9 figures

We report multi-epoch Very Long Baseline Interferometry (VLBI) study of the innermost jet of 3C 84. We carried out 14-epoch VLBI observations during 2006-2009 with the Japanese VLBI Network (JVN) and the VLBI Exploration of Radio Astrometry (VERA), immediately following the radio outburst that began in 2005. Comparison between VLBI lightcurve and single-dish lightcurve indicates that the outburst was associated with the central ~1 pc core. We found that this outburst accompanied the emergence of a new component, and the projected speed of this new component was 0:23c from 2007/297 (2007 October 24) to 2009/114 (2009 April 24). We argue the site of gamma-ray emission detected by Fermi/LAT and jet kinematics in connection with gamma-ray emission mechanism., Comment: Proceedings of the Workshop "Fermi meets Jansky - AGN in Radio and Gamma-Rays", Savolainen, T., Ros, E., Porcas, R.W. & Zensus, J.A. (eds.), MPIfR, Bonn, June 21-23 2010

We study photonic band structure of two- and three-dimensional magnetophotonic crystals and the polarization properties of their eigenmodes using a plane wave expansion method. The alteration of the photonic band structure and eigenmodes by magnetization are examined. Two orientations are studied: in-plane magnetization and perpendicular magnetization. The magnetization-induced symmetry breaking effects are shown to be responsible for the formation of exotic magnetic Bloch modes, comprised of two or more coupled symmetric and antisymmetric Bloch modes of the corresponding non-magnetic photonic crystal. These results imply that uncoupled states of non-magnetic photonic crystals can be excited, or become coupled, in magnetic structures. We show that the polarization state of magnetic Bloch modes is very complicated. In the particular case of perpendicular to plane magnetization they represent in-plane elliptically (or even circularly) polarized waves with large longitudinal component., Comment: 18 pages, 8 figures

We present multi-frequency simultaneous VLBA observations at 15, 22 and 43 GHz towards the nucleus of the nearby radio galaxy NGC 1052. These three continuum images reveal a double-sided jet structure, whose relative intensity ratios imply that the jet axis is oriented close to the sky plane. The steeply rising spectra at 15-43 GHz at the inner edges of the jets strongly suggest that synchrotron emission is absorbed by foreground thermal plasma. We detected H_2O maser emission in the velocity range of 1550-1850 km/s, which is redshifted by 50-350 km/s with respect to the systemic velocity of NGC 1052. The redshifted maser gas appears projected against both sides of the jet, similar to the HI seen in absorption. The H_2O maser gas is located where the free-free absorption opacity is large. This probably implies that the masers in NGC 1052 are associated with a circumnuclear torus or disk as in the nucleus of NGC 4258. Such circumnuclear structure can be the sense of accreting onto the central engine., Comment: 4 pages, 5 figures, accepted for publication in Astronomische Nachrichten (issue dedicated to the Proceedings of "The 4th Workshop on Compact Steep Spectrum and GHz-Peaked Spectrum Radio Sources" held at Riccione, Italy, 26-29 May 2008)

We report the observation of a Fano resonance between continuum Mie scattering and a narrow Bragg band in synthetic opal photonic crystals. The resonance leads to a transmission spectrum exhibiting a Bragg dip with an asymmetric profile, which can be tunably reversed to a Bragg rise. The Fano asymmetry parameter is linked with the dielectric contrast between the permittivity of the filler and the specific value determined by the opal matrix. The existence of the Fano resonance is directly related to disorder due to non-uniformity of a-SiO2 opal spheres. Proposed theoretical "quasi-3D" model produces results in excellent agreement with the experimental data.

Third-order nonlinear optical effects in photonic microcavities are studied. Significant light defocusing in the thin nonlinear microcavity spacer was observed. The polarization self-action effect was detected, when the large nonlinear polarization rotation angle arises when exciting the microcavity mode, being proportional to the radiation intensity., Comment: 3 pages, 4 figures, published in russian at Pis'ma v Zhurnal Eksperimental'noi i Teoreticheskoi Fiziki Vol. 84, N. 8, pp. 529-532 (2006)

Nonlinear-optical manifestations of the Borrmann effect that are consequences of the spectral dependence of the spatial distributions of the electromagnetic field in a structure are observed in one-dimensional photonic crystals. The spectrum of the light self-focusing effect corresponding to the propagation-matrix calculations has been measured near the edge of the photonic gap., Comment: 4 pages, 3 figures, published in russian at Pis'ma v Zhurnal Eksperimental'noi i Teoreticheskoi Fiziki, 2008, Vol. 87, No. 8, pp. 461-464

We demonstrate the existence of a spectrally narrow localized surface state, the so-called optical Tamm state, at the interface between a 1D magnetophotonic and non-magnetic photonic crystals. The state is spectrally located inside the photonic band gaps of each of the photonic crystals comprising this magnetophotonic structure. This state is associated with a sharp transmission peak through the sample and is responsible for the substantial enhancement of the Faraday rotation for the corresponding wavelength. The experimental results are in excellent agreement with the theoretical predictions.

Spectroscopy of magnetization-induced second-harmonic generation (MSHG) is studied in magnetic Co$_{x}$Ag$_{1-x}$ granular films containing Co nanoparticles. A strong resonance of the magnetic contrast of the second-harmonic generation (SHG) intensity is observed in the two-photon energy range from 3,8 eV to 4,5 eV. The local surface plasmons exited in magnetic Co nanogranules in this spectral range assist MSHG and are responsible for a significant enhancement of the SHG magnetic contrast due to the resonances of local optical fields.

We investigate the high-frequency radio spectra of twenty low-luminosity active galactic nuclei (LLAGNs) with compact radio cores. Our millimetre survey with the Nobeyama Millimetre Array (NMA) and analyses of submillimetre archival data that had been obtained with the Submillimetre Common User Bolometer Array (SCUBA) on the James Clerk Maxwell Telescope (JCMT) reveal the following properties. At least half of the LLAGNs show inverted spectra between 15 and 96 GHz; we use published data at 15 GHz with the Very Large Array (VLA) in a 0.15-arcsec resolution and our measurements at 96 GHz with the NMA in a 7-arcsec resolution. The inverted spectra are not artificially made due to their unmatched beam sizes, because of little diffuse contamination from dust, H II regions, or extended jets in these LLAGNs. Such high-frequency inverted spectra are apparently consistent with a `submillimetre bump', which is predicted by an advection-dominated accretion flow (ADAF) model. We find a strong correlation between the high-frequency spectral index and low-frequency core power measured with very-long-baseline-interferometry (VLBI) instruments. The inverted spectra were found exclusively in low-core-power sources, while steep spectra were in high-core-power ones with prominent pc-scale jets. This suggests that the ADAF and nonthermal jets may coexists. The flux ratios between disc and jet seem to be different from LLAGN to LLAGN; disc components can be seen in nuclear radio spectra only if the jets are faint., Comment: 15 pages, 5 figures. Accepted for publication in MNRAS

At the altitude of 3,370 m on the Peruvian Andes, a 32m antenna owned by the telecommunications company Telefonica del Peru will be transformed to a Radio Telescope, it would be transferred to the Geophysical Institute of Peru (IGP). The parabolic antenna was constructed in 1984 by Nippon Electric Co. (NEC) and worked as an INTELSAT station until 2000. A team of the National Observatory of Japan (NAOJ) evaluated the antenna in 2003 and reported its availability to be used as a Radio Telescope. In collaboration of the NAOJ a 6.7 GHz receiver is under construction and will be installed within this year. Initially the telescope as a single dish will monitor and survey Methanol Maser of YSO, higher frequencies equipment and VLBI instruments will be considered. The antenna will be managed by the IGP and used by universities in Peru, becoming a VLBI station will be a grate contribution to astronomy and geodetic community., Comment: 2 pages. 1 figure. Proceedings of the 7th European VLBI Network Symposium held in Toledo, Spain on October 12-15, 2004. Editors: R. Bachiller, F. Colomer, J.-F. Desmurs, P. de Vicente (Observatorio Astronomico Nacional), p. 295-296. Needs evn2004.cls

A second generation near-term space VLBI mission, VSOP-2, is being planned for a launch in 2010 or soon after. The scientific objectives are very high angular resolution imaging of astrophysically exotic regions, including the cores, jets, and accretion disks of active galactic nuclei (AGN), water maser emissions, micro-quasars, coronae of young stellar objects, etc. A highest angular resolution of about 40 microarcseconds is achieved in the 43 GHz band. Engineering developments are in progress for the deployable antenna, antenna pointing, high data rate transmission, cryogenic receivers, accurate orbit determination, etc., to realize this mission. International collaboration will be as important as it has been for VSOP., Comment: 4 pages. 3 figures. Proceedings of the 7th European VLBI Network Symposium held in Toledo, Spain on October 12-15, 2004. Editors: R. Bachiller, F. Colomer, J.-F. Desmurs, P. de Vicente (Observatorio Astronomico Nacional), p. 285-288. Needs evn2004.cls

We report results of pentachromatic VLBI survey for 18 GHz-peaked spectrum sources. Spectral fitting at every pixel across five frequencies allows us to illustrate distribution of optical depth in terms of free-free absorption or synchrotron self absorption. Quasars and Seyfert 1 sources show one-sided morphology with a core at the end where the optical depth peaks. Radio galaxies and Seyfert 2 show symmetric double-sided jets with a optically thick core at the center., Comment: 2 pages. 3 figures. Proceedings of the 7th European VLBI Network Symposium held in Toledo, Spain on October 12-15, 2004. Editors: R. Bachiller, F. Colomer, J.-F. Desmurs, P. de Vicente (Observatorio Astronomico Nacional), p. 157-158. Needs evn2004.cls

The VLBI activities in the East Asia region are planning to coordinate among VLBI groups and institutes in China, Japan, and Korea. In these countries, some new projects are going to start or discussed, and some types of collaboration have been already done individually. These new projects are briefly introduced. Under these circumstances, an organization has been discussed for the coordinated efforts to produce fruitful results more effectively., Comment: 2 pages. no figures. Proceedings of the 7th European VLBI Network Symposium held in Toledo, Spain on October 12-15, 2004. Editors: R. Bachiller, F. Colomer, J.-F. Desmurs, P. de Vicente (Observatorio Astronomico Nacional), p. 279-280. Needs evn2004.cls

We report on the results of a 14 year long VLBI study of proper motions in the IC133 H2O maser source in the galaxy M33. The method of Ordered Motion Parallax was used to model the 3-dimensional structure and dynamics of IC133 and obtain a distance estimate, 800 +/- 180 kpc. Our technique for determining the distance to M33 is independent of calibrations common to other distance indicators, such as Cepheid Period-Luminosity relations, and therefore provides an important check for previous distance determinations., Comment: Accepted for publication in the Astrophysical Journal

W75N is a star-forming region containing various ultracompact HII regions and OH, water, and methanol maser emission. Our VLBA map shows that the OH masers are located in a thin disk rotating around an O-star which is the exciting star of the ultracompact HII region VLA1. A separate set of maser spots is connected with the ultracompact HII region VLA2. The radial velocity of OH maser spots varies across the disk from 3.7 km/s to 10.9 km/s. The diameter of the disk is 4000 A.U. All maser spots are strongly polarized. This are the first OH masers showing nearly 100 per cent linear polarization in several spots. Two maser spots seem to be Zeeman pairs corresponding to a magnetic field of 5.2 mgauss and 7.7 mgauss, and in one case we tentatively found a Zeeman pair consisting of two linearly polarized components. The linearly polarized maser spots are shown to be sigma-components which is the case of the magnetic field being perpendicular to the line of sight. The direction of the magnetic field as determined from linearly polarized spots is perpendicular to the plane of the disk, although the galactic Faraday rotation may significantly affect this conclusion., Comment: 14 figures, 1 table, 27 pages. accepted for publication in ApJ, scheduled for v.564, N1, 2002

A subparsec-scale dense plasma torus around an active galactic nucleus (AGN) is unveiled. We report on very-long-baseline interferometry (VLBI) observations at 2.3, 8.4, and 15.4 GHz towards the active galaxy NGC 1052. The convex spectra of the double-sided jets and the nucleus imply that synchrotron emission is obscured through free--free absorption (FFA) by the foreground cold dense plasma. A trichromatic image was produced to illustrate the distribution of the FFA opacity. We found a central condensation of the plasma which covers about 0.1 pc and 0.7 pc of the approaching and receding jets, respectively. A simple explanation for the asymmetric distribution is the existence of a thick plasma torus perpendicular to the jets. We also found an ambient FFA absorber, whose density profile can be ascribed to a spherical distribution of the isothermal King model. The coexistence of torus-like and spherical distributions of the plasma suggests a transition from radial accretion to rotational accretion around the nucleus., Comment: 10 pages, to appear in Publ. Astron. Soc. Japan, vol.53, No.2 (2001)

The high power test model of biperiodic L-support disk-and- washer was fabricated. Among some trouble in the fabrication, the main one was a vacuum leak in a brazing process. The repair test of the leak showed a good result; four units were recovered out of five leak units (recover rate 80%). While an accelerating mode frequency was tuned at an operating frequency of 2857 MHz by squeezing method, a coupling mode frequency of 2847MHz and the 3.4% field flatness (peak to peak ratio) were achieved., Comment: 3 pages Linac2000 Poster TUA22 (5 figures available from author)

In order to investigate the genesis of powerful radio jet, we have mapped the central 10 pc region of the nearby radio galaxy NGC 6251 with a 0.2 pc resolution using Very Long Baseline Interferometer (VLBI) at two radio frequencies, 5 GHz and 15 GHz, we have found the sub-parsec-scale counterjet for the first time in this radio galaxy. This discovery allows us to investigate the jet acceleration based on the relativistic beaming model., Comment: 7 pages with 7 figures. To appear in PASJ, 52, No. 5, Oct. 25, 2000

Mapping the central 5 pc region of the nearby radio galaxy NGC 6251 with a 0.2 pc resolution using VLBI at two radio frequencies, 5 GHz and 15 GHz, we have found the sub-pc-scale counter jet for the first time in this radio galaxy. This discovery allows us to investigate the jet acceleration based on the relativistic beaming model (Ghisellini et al. 1993)., Comment: 4 pages, 3 figures, to be published in "Astrophysical Phenomena Revealed by Space VLBI" eds. H. Hirabayashi, P.G. Edwards and D.W. Murphy

We present a high resolution 1.6 GHz VSOP image of the southern blazar PKS 1921-293. The image shows a typical core-jet morphology, consistent with ground-based VLBI images. However, the addition of data from the space antenna has greatly improved the angular resolution (especially along the north-south direction for this source), and thus allowed us to clearly identify the core. Model fitting reveals an inner jet component ~1.5 mas north of the core. This jet feature may be moving on a common curved path connecting the jet within a few parsecs to the 10-parsec-scale jet. The compact core has a brightness temperature of 2.6*10**12 K (in the rest frame of the quasar), an indication of relativistic beaming. We analyzed the source in terms of three models, involving the inverse Compton catastrophe, an inhomogeneous relativistic jet, and the equipartition of energy between the radiating particles and the magnetic field. Our analysis of this gamma-ray-quiet blazar shows no preference to any particular one of these models., Comment: 7 pages including 2 figures and 1 table, PASJLaTeX, accepted for publication in PASJ

The water maser in the mildly active nucleus in the nearby galaxy NGC4258 traces a thin, nearly edge-on, subparsec-scale Keplerian disk. Using the technique of very long baseline interferometry, we have detected the proper motions of these masers as they sweep in front of the central black hole at an orbital velocity of about 1100 km/s. The average maser proper motion of 31.5 microarcseconds per year is used in conjunction with the observed acceleration of the masers to derive a purely geometric distance to the galaxy of 7.2 +- 0.3 Mpc. This is the most precise extragalactic distance measured to date, and, being independent of all other distance indicators, is likely to play an important role in calibrating the extragalactic distance scale., Comment: 11 pages, 3 figures. Accepted for publication in Nature

There are applications, which require MeV-range multiple-beams consisting of a large number of identical highly packed beamlets. The multiple-beam RFQ (MB-RFQ) arranged as a matrix array of longitudinal rod-electrodes is appropriate candidate. A configuration of MB-RFQ resonator should ensure identical quadrupole fields in every accelerating channel. The MB-RFQ resonators based on TEM transmission lines are studied. The resonators are designed by a periodical multiplication of a 4-rod unit cell in transverse direction. To understand fields of resonator the normal mode technique is applied. Novel configurations of MB-RFQ resonators based on these normal modes are generated. The RF properties of resonators are verified with computer simulations done with MAFIA code. Beam dynamics study for the initial 400-keV MB-RFQ has been performed using PARMTEQ code. The MB-RFQ parameters and the results of beam dynamics simulations are presented. The calculated beam transmission is 33% at injection of 50-keV, 20mA deuteron beam., Comment: 7 pages, 19 figures

We report a 3 sigma upper limit of 220 microJanskys 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 about 100 Schwarzschild radii., Comment: 11 pages, 1 figure, to be published in ApJ Letters