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We present radio continuum observations of the high-mass young stellar object (HMYSO) G345.4938+01.4677 made using the Australia Telescope Compact Array (ATCA) at 5, 9, 17, and 19 GHz. These observations provide definite evidence that the…

Solar and Stellar Astrophysics · Physics 2016-08-17 Andrés E. Guzmán , Guido Garay , Luis F. Rodríguez , Yanett Contreras , Catherine Dougados , Sylvie Cabrit

A re-analysis of the radio continuum emission from circumnuclear regions of the barred galaxies NGC 1022, 1326 & 4314 is presented. The spatial distributions of Halpha and radio continuum are similar and suggest the existence of several…

Astrophysics · Physics 2009-10-31 Jose Franco , J. Antonio Garcia-Barreto , Eduardo de la Fuente

We have found strong selective emission of the N II 5000A complex in the spectrum of the LMC hypergiant HDE 269896, ON9.7 Ia$^+$. Since this object also has anomalously strong He II $\lambda$4686 emission for its spectral type, an unusually…

Astrophysics · Physics 2015-05-13 Mariela A. Corti , Nolan R. Walborn , Christopher J. Evans

We present the results of near-infrared [Fe II] and H2 line imaging and spectroscopic observations of the supernova remnant 3C 396 using the Palomar 5 m Hale telescope. We detect long, filamentary [Fe II] emission delineating the inner edge…

Astrophysics · Physics 2011-02-11 Ho-Gyu Lee , Dae-Sik Moon , Bon-Chul Koo , Jae-Joon Lee , Keith Matthews

We present echelle spectrophotometry of the Galactic H II region S 311. The data have been taken with the Very Large Telescope UVES echelle spectrograph in the 3100 to 10400 angstroms range. We have measured the intensities of 263 emission…

Astrophysics · Physics 2009-11-13 J. Garcia-Rojas , C. Esteban , A. Peimbert , M. Peimbert , M. Rodriguez , M. T. Ruiz

We report the results of our observations of HI absorption towards the central region of the rejuvenated radio galaxy 4C29.30 (J0840+2949) with the Giant Metrewave Radio Telescope (GMRT). The radio source has diffuse, extended emission with…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Yogesh Chandola , D. J. Saikia , Neeraj Gupta

We present an analysis of super-giant molecular complexes (SGMCs) in the overlap region of the Antennae galaxy merger, based on ALMA CO(3-2) interferometry and VLT/SINFONI imaging spectroscopy of H2 1-0 S(1) at angular resolutions of 0.9"…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Cinthya N. Herrera , François Boulanger , Nicole P. H. Nesvadba , Edith Falgarone

HII regions made of gas ionized by radiations from young massive stars, are widely distributed in the Milky Way. They are tracers for star formation, and their distributions are correlated with the Galactic spiral structure. Radio…

Astrophysics of Galaxies · Physics 2021-11-03 Chuan-Peng Zhang , Jin-Long Xu , Guang-Xing Li , Li-Gang Hou , Nai-Ping Yu , Peng Jiang

Ground-based and Hubble Space Telescope observations are presented for SN 1993J and SN 1998S. SN 1998S shows strong, relatively narrow circumstellar emission lines of N III-V and C III-IV, as well as broad lines from the ejecta. Both the…

Deep optical CCD images of the supernova remnant G 32.8-0.1 were obtained where filamentary and diffuse emission was discovered. The images were acquired in the emission lines of Halpha+[N II] and [S II]. Filamentary and diffuse structures…

Astrophysics of Galaxies · Physics 2015-05-13 P. Boumis , E. M. Xilouris , J. Alikakos , P. E. Christopoulou , F. Mavromatakis , A. C. Katsiyannis , C. D. Goudis

We present spectral line mapping observations toward four massive star-forming regions (Cepheus A, DR21S, S76E and G34.26+0.15), with the IRAM 30 meter telescope at 2 mm and 3 mm bands. Totally 396 spectral lines from 51 molecules, one…

Astrophysics of Galaxies · Physics 2017-01-18 Shanghuo Li , Junzhi Wang , Zhi-Yu Zhang , Min Fang , Juan Li , Jiang- shui Zhang , Junhui Fan , Qingfeng Zhu , Fei Li

We revisit the observed correlation between Hbeta and FeII velocities for Type II-P supernovae (SNe~II-P) using 28 optical spectra of 13 SNe II-P and demonstrate that it is well modeled by a linear relation with a dispersion of about 300…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Dovi Poznanski , Peter E. Nugent , Alexei V. Filippenko

We present the most sensitive ultraviolet observations of Supernova 1987A to date. Imaging spectroscopy from the Hubble Space Telescope-Cosmic Origins Spectrograph shows many narrow (dv \sim 300 km/s) emission lines from the circumstellar…

We have detected C91$\alpha$ (8.5891 GHz) emission toward 4 ultra-compact \HII regions (\UCHII s; W49G, J, L & C) in the W49 North massive star forming region with the Very Large Array (VLA) at 3\arcsec resolution. No carbon line emission…

Astrophysics · Physics 2007-05-23 D. Anish Roshi , C. G. De Pree , W. M. Goss , K. R. Anantharamaiah

We study the presence of low intensity high velocity components, which we have termed wing features in the integrated Halpha emission line profiles of the HII region populations of the spiral barred galaxies NGC 1530, NGC 3359 and NGC 6951.…

Astrophysics · Physics 2009-11-10 M. Relano , J. E. Beckman

The star HD72089 is located behind the Vela supernova remnant and shows a complex array of high and low velocity interstellar absorption features arising from shocked clouds. A spectrum of this star was recorded over the wavelength range…

Although variations in elemental abundance ratios in the Milky Way Galaxy certainly exist, details remain uncertain, particularly in the inner Galaxy, where stars and H II regions in the Galactic plane are obscured optically. In this paper…

We present H-alpha velocity fields of thirteen giant H II regions in four nearby dwarf irregular galaxies, NGC 2366, Holmberg II, IC 2574, and WLM. We classify the velocity features as well as the morphologies of the H II regions. The…

Astrophysics · Physics 2009-10-30 A. Tomita , K. Ohta , K. Nakanishi , T. T. Takeuchi , M. Saito

We present 250~GHz continuum and H29alpha line data toward W49N:A2, a hypercompact HII region ionized by an O9 star. The data obtained with ALMA at a resolution of ~0"05 (600 au) confirmed the presence of an ionized ring with a radius…

Solar and Stellar Astrophysics · Physics 2023-01-04 Ryosuke Miyawaki , Masahiko Hayashi , Tetsuo Hasegawa

We use early-time observations of He I 10830 \AA to measure the extent of upward mixing of radioactive material in SN 1987A. This work develops and extends the work of Graham (1988), and places constraints on actual explosion models. The…

Astrophysics · Physics 2016-08-30 A. Fassia , W. P. S. Meikle