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Both in the Faraday Rotation Measure and the intrinsic polarization angle, new features are revealed to indicate a helical magnetic field operating along the jet of the bright active galactic nuclei 3C 273. The helical field has been suggested to be related to the formation and collimation of jets by magnetohydrodynamic models. The distribution of the RM shows a systematic gradient with respect to the jet axis, which is expected by a helical magnetic field. In addition, the helical field can consistently explain two types in the direction of the projected magnetic field: parallel and perpendicular to the jet axis. Further, if the helical magnetic field is generated by winding up of an initial field by rotation of the accretion disk, we can uniquely determine the direction of the disk rotation, since the jet is approaching us., Comment: 7 pages, 5 figures, PASJ Letters in press

Since the year 2000, our hospital has been equipped with an intensity modulated radiation therapy (IMRT) facility. Before IMRT is administered, the absorbed dose is measured by the ionization chamber to provide verification for the IMRT procedure. In utilizing the current point dose evaluation, large discrepancies have been experienced when the measured dose is compared with the calculated dose. This discrepancy is due to the lack of uniformity in IMRT irradiation in comparison with that of the present method of dose distribution. In order to reduce the margin of error, the average dose of the ionization chamber calculated on a dose-volume histogram was compared with the measured dose. As a result, the margin of error was minimized to

The Atacama Large Millimeter/submillimeter Array (ALMA) is already producing a growing number of impressive and scientifically compelling results during its first two years of operation as the most powerful mm/submm interferometer in the world. However, ALMA still has some scientific weak points due to the technological limitations. In order to maintain ALMA as the state-of-the-art facility over the course of its projected life of 30+ years, continuing technical upgrades and developments for new capabilities are essential. We have already performed future development studies and projects for ALMA enhancement, which are the main development focus for the next 5 - 10 years. We should now start the discussion of the technical requirements and the potential science achievable with larger scale developments which are envisioned in the next 10 - 20 years, because it is emphasized that the larger scale project will likely result in higher impact, groundbreaking ALMA science in the year 2034 and beyond.

Pointing performance of a radio telescope antenna is important in radio astronomical observations to obtain accurate intensity of a target source. The pointing errors of the ALMA ACA antenna are required to be better than 0.6 arcsec rss, which corresponds to 1/10 and 1/20 of the field of view of the ALMA ACA 12-m and 7-m antenna at 950 GHz, respectively. The pointing verification measurements of the ACA antenna were performed using an Optical pointing telescope (OPT) mounted on the antenna backup structure at the ALMA Operations Site Facility at 2900m above the sea level. Pointing errors of these OPT measurements contain three different origins; originated from antenna, originated of atmosphere (optical seeing), and originated of OPT itself. In order to estimate pointing errors of the antenna origin, we need to subtract the components of optical seeing and OPT itself accurately, while we need to add components that cannot be measured in the OPT measurements. The ACA antenna verification test report demonstrated that all the ACA 7-m antenna meets pointing specification of ALMA. However, about one-third of datasets, values of estimated optical seeing is larger than measured pointing errors. We re-examined a procedure to estimate optical seeing, by investigating the property of optical seeing from the high-sampling OPT pointing measurements of long tracking a bright star for 15 minutes. Particularly, we examined the relation between optical seeing and sampling rate derived from Kolmogorov PSD. Our analysis indicated that the optical seeing at ALMA site may have been overestimated in the verification test. We present a new relation between optical seeing and sampling rate proportional to average wind velocity during measurement. We used this new relation to derive the optical seeing and as a result the number of datasets becomes half in which the optical seeing is larger than measured pointing errors. As a result, we successfully develop a new verification method of optical seeing that has high reliability.

An enantioselective synthesis of an epoxybicyclo[7.3.0]dodecenediyne core system of the neocarzinostatin chromophore has been achieved via intramolecular acetylide addition and palladium-mediated coupling of iodocyclopentene 5 with alkyne 6. The key cyclopentene moiety, trans-4,5-dihydroxy-2-cyclopenten-1-one 7, was conveniently prepared in both enantiomerically pure forms via enzymatic desymmetrization of meso-3,4,5-trans,trans-trihydroxycyclopentene derivatives.

We investigate whether a pc-scale jet of 3C345 is dominated by a normal plasma or an electron-positron plasma. We present a general condition that a jet component becomes optically thick for synchrotron self-absorption, by extending the method originally developed by Reynolds et al. The general condition gives a lower limit of the electron number density, with the aid of the surface brightness condition, which enables us to compute the magnetic field density. Comparing the lower limit with another independent constraint for the electron density that is deduced from the kinetic luminosity, we can distinguish the matter content. We apply the procedure to the five components of 3C345 (C2, C3, C4, C5, and C7) of which angular diameters and radio fluxes at the peak frequencies were obtainable from literature. Evaluating the representative values of Doppler beaming factors by their equipartition values, we find that all the five components are likely dominated by an electron-positron plasma. The conclusion does not depend on the lower cutoff energy of the power-law distribution of radiating particles., Comment: 17 pages

We have investigated whether a pc-scale jet of 3C 279 is dominated by a normal plasma or an electronpositron plasma. By analyzing Very Long Baseline Interferometry data between 1983 and 1990, and utilizing the theory of synchrotron self-absorption, we have derived the lower limits for the proper electron number density. Comparing the lower limit with another independent constraint for the electron density that is deduced from the kinetic luminosity, we find that the core and components C3 and C4 are likely dominated by an electron-positron plasma.

Supermassive black hole binaries may exist in the centers of active galactic nuclei like quasars and radio galaxies and mergers between galaxies may result in the formation of supermassive binaries during the course of galactic evolution. Using the very-long-baseline interferometer, we imaged the radio galaxy 3C 66B at radio frequencies and found that the unresolved radio core of 3C 66B shows well-defined elliptical motions with a period of 1.05 +/- 0.03 years, which provides a direct detection of a supermassive black hole binary., 8 pages, 3 figures, to appear in the Science

In signal transmission through optical fiber, cable length delay fluctuation accompanied by chromatic and polarization-mode dispersion affects the coherence of distributed signals. To maintain signal coherence, it is very important to generate very-high-frequency signals with minimum phase noise and transmission loss. In a photonic local signal generation/distribution system with a microwave-photonic signal generator and a real-time microwave-photonic signal phase stabilizer that we developed as an alternative photonic LO system for ALMA (Atacama Large Millimeter/sub-millimeter Array), signals are transmitted in the form of frequency difference between two coherent light waves, effectively maintaining the coherence of distributed reference signals. Through the development of the real-time phase stabilizer, we discovered that the system would be further improved with the introduction of a post-processing scheme phase stabilizer and confirmed its effectiveness by experiments.

ALMA (Atacama Large Millimeter/submillimeter Array) is a revolutionary radio telescope and its early scientific operation has just started. It is expected that ALMA will resolve several cosmic questions and will give us a new cosmic view. Our passion for astronomy naturally goes beyond ALMA because we believe that the 21st-century astronomy should pursue the new scientific frontier. In this conference, we propose a project of the future radio telescope to search for habitable planets and finally detect 2nd Earth as a migratable planet. Detection of 2nd Earth is one of the ultimate dreams not only for astronomers but also for every human being. To directly detect 2nd Earth, we have to carefully design the sensitivity and angular resolution of the telescope by conducting trade-off analysis between the confusion limit and the minimum detectable temperature. The result of the sensitivity analysis is derived assuming an array that has sixty-four (64) 50-m antennas with 25-;μm surface accuracy mainly located within the area of 300 km (up to 3000 km), dual-polarization SSB receivers with the best noise temperature performance achieved by ALMA or better, and IF bandwidth of 128 or 256 GHz.. We temporarily name this telescope "Very Large Millimeter/Submillimeter Array (VLMSA)". Since this sensitivity is extremely high, we can have a lot of chances to study the galaxy, star formation, cosmology and of course the new scientific frontier.

ISBN: 9780819491534; International audience; Two large correlators have been constructed to combine the signals captured by the ALMA antennas deployed on the Atacama Desert in Chile at an elevation of 5050 meters. The Baseline correlator was fabricated by a NRAO/European team to process up to 64 antennas for 16 GHz bandwidth in two polarizations and another correlator, the Atacama Compact Array (ACA) correlator, was fabricated by a Japanese team to process up to 16 antennas. Both correlators meet the same specifications except for the number of processed antennas. The main architectural differences between these two large machines will be underlined. Selected features of the Baseline and ACA correlators as well as the main technical challenges met by the designers will be briefly discussed. The Baseline correlator is the largest correlator ever built for radio astronomy. Its digital hybrid architecture provides a wide variety of observing modes including the ability to divide each input baseband into 32 frequency-mobile sub-bands for high spectral resolution and to be operated as a conventional 'lag' correlator for high time resolution. The various observing modes offered by the ALMA correlators to the science community for 'Early Science' are presented, as well as future observing modes. Coherently phasing the array to provide VLBI maps of extremely compact sources is another feature of the ALMA correlators. Finally, the status and availability of these large machines will be presented.

We have developed an FX-architecture digital spectro-correlator for the Atacama Compact Array (ACA) of the Atacama Large Millimeter/submillimeter Array. The correlator is able to simultaneously process four pairs of dual polarization signals with the bandwidth of 2 GHz, which are received by up to sixteen antennas. It can calculate auto- and cross-correlation spectra including cross-polarization in all combinations of all the antennas, and output correlation spectra with flexible spectral configuration such as multiple frequency ranges and multiple frequency resolutions. Its spectral dynamic range is estimated to be higher than 10^4 relative to Tsys from processing results of thermal noise for eight hours with a typical correlator configuration. The sensitivity loss is also confirmed to be 0.9 % with the same configuration. In this paper, we report the detailed design of the correlator and the verification results of the developed hardware., Comment: To be published in PASJ, 64

Coupling of functionalized cyclopentenyl iodides with ethynyl oxiranes has been achieved by using catalytic amount of Pd(CH3CN)2Cl2 and CuI in the presence of i-Pr2NEt in moderate to good yields.

An enantioselective synthesis of an epoxybicyclo[7.3.0]dodecenediyne core system of the neocarzinostatin chromophore has been achieved via intramolecular acetylide addition and palladium-mediated coupling of iodocyclopentene 5 with alkyne 6. The key cyclopentene moiety, trans-4,5-dihydroxy-2-cyclopenten-1-one 7, was conveniently prepared in both enantiomerically pure forms via enzymatic desymmetrization of meso-3,4,5-trans,trans-trihydroxycyclopentene derivatives.

We established a new algorithm for correlation process in radio astronomy. This scheme consists of the 1st-stage Fourier Transform as a filter and the 2nd-stage Fourier Transform for spectroscopy. The "FFX" correlator stands for Filter and FX architecture, since the 1st-stage Fourier Transform is performed as a digital filter, and the 2nd-stage Fourier Transform is performed as a conventional FX scheme. We developed the FFX correlator hardware not only for the verification of the FFX scheme algorithm but also for the application to the Atacama Submillimeter Telescope Experiment (ASTE) telescope toward high-dispersion and wideband radio observation at submillimeter wavelengths. In this paper, we present the principle of the FFX correlator and its properties, as well as the evaluation results with the production version., Comment: 20 figures

8-Gsps 1-bit Analog-to-Digital Converters (ADCs) were newly developed toward the realization of the wideband observation. The development of the wideband ADCs is one of the most essential developments for the radio interferometer. To evaluate its performance in interferometric observations, the time (phase) stability and frequency response were measured with a noise source and a signal generator. The results of these measurements show that the developed ADCs can achieve the jitter time less than 0.05 psec at the time interval of 1 sec, the passband frequency response with the slope less than 0.73 dB/GHz and the ripple less than 1.8 dB, and the aperture time less than 20 psec. The details of the developed ADC design, the measurement methods, and the results of these measurements are presented in this paper., Comment: Accepted for publication in PASJ. 19 pages, 15 figures

We present an estimate of the mass of the supermassive black hole (SMBH) in the nearby type-1 Seyfert galaxy \object{NGC 1097} using Atacamma Large Millimeter/Submillimeter Array (ALMA) observations of dense gas kinematics. Dense molecular gas dynamics are traced with ${\rm HCN} (J=1-0)$ and ${\rm HCO^{+}} (J=1-0)$ emission lines. Assuming a host galaxy inclination of $46^{\circ}$, we derive a SMBH mass, $M_{\rm BH}=1.40^{+0.27}_{-0.32} \times 10^{8}M_{\odot}$, and an I-band mass to light ratio to be $5.14^{+0.03}_{-0.04}$, using ${\rm HCN} (J=1-0)$. The estimated parameters are consistent between the two emission lines. The measured SMBH mass is in good agreement with the SMBH mass and bulge velocity dispersion relationship. Our result showcases ALMA's potential for deriving accurate SMBH masses, especially for nearby late-type galaxies. Larger samples and accurate SMBH masses will further elucidate the relationship between the black hole (BH) and host galaxy properties and constrain the coevolutionary growth of galaxies and BHs.

We present the observational results of the Gamma-ray blazar, 3C 66A, at 2.3, 8.4, and 22 GHz at 4 epochs during 2004-05 with the VLBA. The resulting images show an overall core-jet structure extending roughly to the south with two intermediate breaks occurring in the region near the core. By model-fitting to the visibility data, the northmost component, which is also the brightest, is identified as the core according to its relatively flat spectrum and its compactness. As combined with some previous results to investigate the proper motions of the jet components, it is found the kinematics of 3C 66A is quite complicated with components of inward and outward, subluminal and superluminal motions all detected in the radio structure. The superluminal motions indicate strong Doppler boosting exists in the jet. The apparent inward motions of the innermost components last for at least 10 years and could not be caused by new-born components. The possible reason could be non-stationarity of the core due to opacity change., 24 pages, 4 figures

We report 4-epoch VLBA observations of 3C 66A at 22GHz. The resulting images show a typical core-jet structure. We combine our results with some previous results to investigate the proper motions of the jet components. The kinematics of 3C 66A is quite complicated; mildly superluminal motions as well as apparent inward motions have been detected for some components. The inward motions may imply position change of the observed core.

We have carried out the experiment of real-time space VLBI by using a high-speed ATM network. A space VLBI program is carried out with the HALCA satellite, which has an 8-m diameter radio telescope. Downlink data is transmitted to Usuda station, which is a Japanese data link station. And Usuda 64-m telescope is used as a ground radio telescope. They were used for this experiment. It is the first experiment that an optical fiber network was applied for a real-time space VLBI. The ATM optical-fiber network has 2.4 Gbps transmission capability. For the real-time space VLBI experiment, 128 Mbps data are transmitted. The VLBI correlator at NAOJ is used, which is usually used for the tape based ground and space VLBI observations. And we have succeeded to detect fringes using this network with a satellite downlink station and a ground radio telescope by test data, which are play-backed with recorded tapes. Unfortunately we have not tested actual observations because of a serious trouble of the satellite.

The gigabit digital filter prototype has been developed with the FPGA (FIeld Programmable Gate Array) for the radio astronomical observation. The digital filtering techniques enables a variety of observing modes defined on the data acquisition system, even with a fixed sampling frequency A/D converter. In this study, the principle of gigabit digital filter design is described in detail, parallel processing design of a FIR (Finite Inpulse Response) filter is presented, and the results of the test manufacturing are shown.© (2000) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

This study examined the records of all psychiatric patients hospitalized over 1 year who were committed as a result of a penal code violation at a public sector hospital located in Tokyo, Japan. The 30 patients were all men, Japanese, and primarily unmarried. Affective and organic disorders were totally absent. None of the new antipsychotic medications were used. There was no relationship between nursing diagnosis and Diagnostic and Statistical Manual of Mental Disorders-IV ( DSM-IV ) diagnosis. The demands for health care reform are beginning in Japan. Managing the integration of the long-term psychiatric patient into the community is one of the main challenges identified in this study.

The properties of tidally induced arms provide a means to study molecular cloud formation and the subsequent star formation under environmental conditions which in principle are different from quasi stationary spiral arms. We report the properties of a newly discovered molecular gas arm of likely tidal origin at the south of NGC 4039 and the overlap region in the Antennae galaxies, with a resolution of 1"68 x 0"85, using the Atacama Large Millimeter/submillimeter Array science verification CO(2-1) data. The arm extends 3.4 kpc (34") and is characterized by widths of ~ 200 pc (2") and velocity widths of typically \DeltaV ~ 10-20 km/s . About 10 clumps are strung out along this structure, most of them unresolved, with average surface densities of \Sigma_gas ~ 10-100 Msun pc^{-2}, and masses of (1-8) x 10^6 Msun. These structures resemble the morphology of beads on a string, with an almost equidistant separation between the beads of about 350 pc, which may represent a characteristic separation scale for giant molecular associations. We find that the star formation efficiency at a resolution of 6" (600 pc) is in general a factor of 10 higher than in disk galaxies and other tidal arms and bridges. This arm is linked, based on the distribution and kinematics, to the base of the western spiral arm of NGC 4039, but its morphology is different to that predicted by high-resolution simulations of the Antennae galaxies., Comment: Accepted in ApJL, 8 pages, 5 figures

PKS 1749+096 is a BL Lac object showing weak extended jet emission to the northeast of the compact VLBI core on parsec scales. We aim at better understanding the jet kinematics and variability of this source and finding clues that may applicable to other BL Lac objects. The jet was studied with multi-epoch multi-frequency high-resolution VLBI observations. The jet is characterized by a one-sided curved morphology at all epochs and all frequencies. The VLBI core, located at the southern end of the jet, was identified based on its spectral properties. The equipartition magnetic field of the core was investigated, through which we derived a Doppler factor of 5, largely consistent with that derived from kinematics (component C5). The study of the detailed jet kinematics at 22 and 15 GHz, spanning a period of more than 10 years, indicates the possible existence of a bimodal distribution of the jet apparent speed. Ballistic and non-ballistic components are found to coexist in the jet. Superluminal motions in the range of 5-21 c were measured in 11 distinct components. We estimated the physical jet parameters with the minimum Lorentz factor of 10.2 and Doppler factors in the range of 10.2-20.4 (component C5). The coincidence in time of the component's ejection and flares supports the idea that, at least in PKS 1749+096, ejection of new jet components is connected with major outbursts in flux density. For the best-traced component (C5) we found that the flux density decays rapidly as it travels downstream the jet, accompanied by a steepening of its spectra, which argues in favor of a contribution of inverse Compton cooling. These properties make PKS 1749+096 a suitable target for an intensive monitoring to decipher the variability phenomenon of BL Lac objects., Comment: Replaced to match published version

We present proper motion of the sub-parsec scale jet in a nearby elliptical galaxy 3C 66B. Observations were made using the VLBA and partly Effelsburg 100-m telescope at 2.3 GHz and 8.4 GHz at 10 epochs over 4 years. The 8.4 GHz images showed that a proper motion increases from 0.21 to 0.70 mas/year, corresponding to an apparent speed of 0.30 c to 0.96 c, with a distance from the core on a sub-parsec scale. Our investigation suggests that the apparent increase of the proper motion can be explained by changes in the viewing angle, according to a relativistic beaming model. However, we still cannot eliminate the possibility that acceleration of the jet outflow speed or of changes of emissivity profile in the two-zone jet might be found in 3C 66B., Comment: 29 pages, 12 figures. Accepted for publication in The Astronomical Journal

The actual and future B-ISDN situation is described, together with the field trial of IBIS in JAPAN. The CCITT recommendation of B-ISDN is being published in 1989. The basic NNI (network node interface) of 155.52 Mbps is applicable for the video signal transmission, together with the audio service, N-ISDN service, POTS and other data information services. When the STM-1 signal is induced to the subscriber by optical fiber, the interactive and integrated service will be realized. The interactive and integrated service of field trial is being performed in Osaka Japan. The field trial of "IBIS", which will open up the way to interactive network, is now operating.

Coupling of functionalized cyclopentenyl iodides with ethynyl oxiranes has been achieved by using catalytic amount of Pd(CH3CN)2Cl2 and CuI in the presence of i-Pr2NEt in moderate to good yields.

The first astronomical fringe of a test correlator for the Atacama Large Millimeter/Submillimeter Array (ALMA) is obtained. The newly-developed test correlator system consists of two 4096-Msps Analog-to-Digital Converters (ADCs) and an FX-type correlator that can divide a 2-GHz correlation signal from one baseline into 131072 frequency channels. A fringe spectrum that contains 20 line features as well as continuum emission at ∼ 86.2GHz was obtained by an interferometric observation of the Orion-KL regions using this test system connected to the Nobeyama Millimeter Array (NMA), demonstrating that the realization of high frequency resolution over a wide bandwidth is technically feasible. The installation of such a correlator system in the ALMA will greatly enhance its capability of multi-line imaging.

The ALMA (Atacama Large Millimeter/submillimeter Array) radio interferometer has some di erent types ofantennas which have a variation of gain and leakages across the primary beam of an individual antenna. Wehave been developing an arti cial calibration source which is used for compensation of individual di erence ofantennas. In a high-frequency antenna, using astronomical sources to do calibration measurement would beextremely time consuming, whereas with the arti cial calibration source becomes a realistic possibility. Photonictechniques are considered to be superior to conventional techniques based on electronic devices in terms of widebandwidth and high-frequency signals. Conversion from an optical signal to a millimeter/sub-millimeter wavesignal is done by a photo-mixer.Keywords: ALMA, Calibration source, Photonic, millimeter-wave, sub-millimeter-wave 1. INTRODUCTION The ALMA (Atacama Large Millimeter/sub-millimeter Array) is a high-frequency radio interferometer, whichconsists 54 units of four types of 12-m antenna and 12 units of 7-m antenna. Each antenna has 10 Band-receiversand the highest receiving frequency reaches 950 GHz.