973 research outputs found

    Observations of SiO Maser Sources within a Few Parsec from the Galactic Center

    Get PDF
    Mapping and monitoring observations of SiO maser sources near the Galactic center were made with the Nobeyama 45-m telescope at 43 GHz. Rectangular mapping an area of approximately 200'' x 100''$ in a 30'' grid, and triangular mapping in a 20'' grid toward the Galactic center, resulted in 15 detections of SiO sources; the positions of the sources were obtained with errors of 5--10'', except for a few weak sources. Three-year monitoring observations found that the component at V_lsr=-27 km/s of IRS 10 EE flared to about 1.5 Jy during 2000 March--May, which was a factor of more than 5 brighter than its normal intensity. Using the radial velocities and positions of the SiO sources, we identified 5 which are counterparts of previously observed OH 1612 MHz sources. The other 10 SiO sources have no OH counterparts, but two were previously detected with VLA, and four are located close to the positions of large-amplitude variables observed at near-infrared wavelengths. A least-squares fit to a plot of velocities versus Galactic longitudes gives a rather high speed for the rotation of the star cluster around the Galactic center. The observed radial-velocity dispersion is roughly consistent with a value obtained before. It was found that all of the SiO sources with OH 1612 MHz counterparts have periods of light variation longer than 450 days, while SiO sources without OH masers often have periods shorter than 450 days. This fact suggests that lower-mass AGB stars are more often detected in SiO masers than in the OH 1612 MHz line.Comment: 9 pages, 7 figures. PASJ 54, No. 1 (2002) in pres

    Bright Type II SN 2023ixf in M101: A Quick Analysis of the Early-Stage Spectroscopic and Near-Infrared Light Curves

    Full text link
    We present the early-stage analysis of the low-resolution (R=1000R=1000) optical spectra and the near-infrared light curves of the bright Type II supernova (SN II) 2023ixf in the notable nearby face-on spiral galaxy M101, which are obtained since t=1.7t=1.7 until 8.08.0 d. Our first spectrum shows remarkable emission features of Balmer series, He~{\sc ii}, N~{\sc iv}, and C~{\sc iv} with a strong blue continuum. Compared with SNe II showing the flash-ionized features, we suggest that this SN could be categorized into high-luminosity SNe II with a nitrogen/helium-rich circumstellar material (CSM), e.g., SNe 2014G, 2017ahn, and 2020pni. The H~{α\alpha} emission line is composed of broad (~2800 km~s1^{-1}), intermediate (520 km~s1^{-1}), and narrow (<200<200 km~s1^{-1}) components. The near-infrared light curves are well consistent with those of another luminous SN II 2017ahn, and the absolute magnitudes locate on the bright end in the lumosity distribution of SNe II. These observational facts support that SN 2023ixf is well consistent with a high-luminosity SN II with the dense nitrogen/helium-rich CSM.Comment: 5 pages, 4 figures, submitted to PASJ Letter

    SiO Maser Survey of the Inner Bar of the Galactic Bulge

    Get PDF
    We surveyed 291 MSX/2MASS infrared objects in the 7 x 2 deg area of the galactic center in the 43 GHz SiO J=1--0 v=1 and 2 maser lines, obtaining accurate radial velocities of 163 detected objects. The surveyed area is the region where the IRAS catalog is incomplete due to contamination by high source density. The objects in the present MSX/2MASS sample were chosen to have similar infrared characteristics to those of the previous SiO-maser-survey samples based on the color selected IRAS sources. The sampling based on the 2MASS catalog causes a bias to the foreside objects of the bulge due to heavy obscuration by interstellar dust; the detections are considerably leaned on the V_{lsr}<0 side. The l--v diagram reveals two conspicuous features, which were not present or tenuous in the previous studies: one feature indicating a linear velocity increase with longitude with |l|<1.5 deg, which is likely associated with the inner bar, and the other feature having considerably eccentric velocities more than those of the normal x_1-orbit family feature. The extinction-corrected K magnitudes (if used as a distance modulus) tend to show a sequential deposition of these objects along the line of sight toward the Galactic center depending on their radial velocities. The tendency that appeared in the distance measures is consistent with the bulge-bar dynamical model utilizing the periodic orbit families in the bar potential.Comment: Full high resolution figures available as NRO report No.638 at http://www.nro.nao.ac.jp/library/report/list.html. PASJ 58, No. 3 (June 25 issue in press

    Evaluation of the effect of sagging correction calibration errors in radiotherapy software on image matching

    Get PDF
    To investigate the impact of sagging correction calibration errors in radiotherapy software on image matching. Three software applications were used, with and without a polymethyl methacrylate rod supporting the ball bearings (BB). The calibration error for sagging correction across nine flex maps (FMs) was determined by shifting the BB positions along the Left–Right (LR), Gun–Target (GT), and Up–Down (UD) directions from the reference point. Lucy and pelvic phantom cone-beam computed tomography (CBCT) images underwent auto-matching after modifying each FM. Image deformation was assessed in orthogonal CBCT planes, and the correlations among BB shift magnitude, deformation vector value, and differences in auto-matching were analyzed. The average difference in analysis results among the three softwares for the Winston–Lutz test was within 0.1 mm. The determination coefficients (R2) between the BB shift amount and Lucy phantom matching error in each FM were 0.99, 0.99, and 1.00 in the LR-, GT-, and UD-directions, respectively. The pelvis phantom demonstrated no cross-correlation in the GT direction during auto-matching error evaluation using each FM. The correlation coefficient (r) between the BB shift and the deformation vector value was 0.95 on average for all image planes. Slight differences were observed among software in the evaluation of the Winston–Lutz test. The sagging correction calibration error in the radiotherapy imaging system was caused by an auto-matching error of the phantom and deformation of CBCT images

    Chapter 9 : Clinical and Radiographic Observation of Permanent Teeth with Incompletely Formed Roots after Root Canal Therapy

    Get PDF
    A total of 33 teeth with 66 root canals were clinically diagnosed as irreversible pulpitis, and 38 teeth with 53 canals were diagnosed as apical periodontitis. Those 71 teeth had 119 root canals, with incompletely formed roots, and they underwent root canal therapy and filling using a formulation of calcium hydroxide and iodoform called Vitapex and were clinically observed for 30 to 1312 days. The following are the results and conclusions. 1: After root canal therapy, the condition of the root canal filling material was determined by radiograph In 66 root canals with irreversible pulpitis, 16 cases were overfilled, 11 cases were flush and 39 cases were underfilled. In 53 cases with apical periodontitis, 28 cases were overfilled, 10 cases were flush and 15 cases were underfilled. 2: Clinical discomfort was experienced in 10 cases with irreversible pulpitis and in 3 cases with apical periodontitis. However, most of the discomfort was of a mild degree and disappeared within a week. 3: At the last observation, a high frequency of closure of the root apex was observed by radiograph. Cases with apical periodontitis tend to have a slight delay in inducing closure of the root apex compared with cases with irreversible pulpitis. However, after 540 days, closure of the root apex was observed in all cases. 4: Clinical and radiographic findings show that in 33 cases with irreversible pulpitis, 23 cases were good, 9 cases were fair and 1 case was poor. On the other hand, in 38 cases with apical periodontitis, 35 cases were good, 2 cases were fair and 1 case was poor.Editor, Toshiyuki KawakamiLanguage Editor, David M Carlsonviii, 232 p. ill. (some col.

    A comparison of dust concentration with high resolution analysis and visible strata in the Holocene and Last Glacial Maximum periods from the Dome Fuji ice core, East Antarctica

    Get PDF
    第3回極域科学シンポジウム 横断セッション「海・陸・氷床から探る後期新生代の南極寒冷圏環境変動」11月26日(月)、27日(火) 2階ラウン
    corecore