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Extensive optical and ultraviolet (UV) observations of the type Ia supernova (SN Ia) 2012fr are presented in this paper. It has a relatively high luminosity, with an absolute $B$-band peak magnitude of about $-19.5$ mag and a smaller…

Solar and Stellar Astrophysics · Physics 2015-12-09 JuJia Zhang , XiaoFeng Wang , JinMing Bai , TianMeng Zhang , Bo Wang , ZhengWei Liu , XuLin Zhao , JunCheng Chen

We present a VLT/FORS1 survey of Wolf-Rayet (WR) stars in the spiral galaxy NGC 1313. In total, 94 WR candidate sources have been identified from narrow-band imaging. Of these, 82 have been spectroscopically observed, for which WR emission…

Astrophysics · Physics 2009-11-13 L. J. Hadfield , P. A. Crowther

With a projected size of about 450 kpc at z~2.3, the Slug Ly-alpha nebula is a rare laboratory to study, in emission, the properties of the intergalactic gas in the Cosmic Web. Since its discovery, the Slug has been the subject of several…

K 4-47 is an unusual planetary nebula composed of a compact high-ionization core and a pair of low-ionization knots. Long-slit medium-resolution spectra of the knots and core are analyzed in this paper. Assuming photoionization from the…

Astrophysics · Physics 2009-11-10 D. R. Goncalves , A. Mampaso , R. L. M. Corradi , M. Perinotto , A. Riera , L. Lopez-Martin

We report the discovery of large ionized, [O II] emitting circumgalactic nebulae around the majority of thirty UV luminous quasars at $z=0.4-1.4$ observed with deep, wide-field integral field spectroscopy (IFS) with the Multi-Unit…

Wolf-Rayet ([WR]) and weak emission-line ($wels$) central stars of planetary nebulae (PNe) have hydrogen-deficient atmospheres, whose origins are not well understood. In the present study, we have conducted plasma diagnostics and abundance…

Solar and Stellar Astrophysics · Physics 2021-12-08 A. Danehkar

The Lynx arc, with a redshift of 3.357, was discovered during spectroscopic follow-up of the z=0.570 cluster RX J0848+4456 from the ROSAT Deep Cluster Survey. The arc is characterized by a very red R-K color and strong, narrow emission…

We report the serendipitous discovery of a heavily reddened Wolf-Rayet star that we name WR142b. While photometrically monitoring a cataclysmic variable, we detected weak variability in a nearby field star. Low-resolution spectroscopy…

Solar and Stellar Astrophysics · Physics 2015-06-03 Colin Littlefield , Peter Garnavich , G. H. Howie Marion , Jozsef Vinko , Colin McClelland , Terrence Rettig , J. Craig Wheeler

The composite galaxy NGC 4102 hosts a LINER nucleus and a starburst. We mapped NGC 4102 in the 12.8 micron line of [NeII], using the echelon spectrometer TEXES on the NASA IRTF, to obtain a data cube with 1.5" spatial and 25 km/s spectral,…

Astrophysics of Galaxies · Physics 2015-05-19 Sara C. Beck , John H. Lacy , Jean L. Turner

SBS0335-052E, one of the most metal-poor (Z ~ 3-4% Z$_{\odot}$) HeII-emitter starbursts known in the nearby universe, is studied using optical VLT/MUSE spectroscopic and Chandra X-ray observations. We spatially resolved the spectral map of…

Astrophysics of Galaxies · Physics 2018-08-01 C. Kehrig , J. M. Vilchez , M. A. Guerrero , J. Iglesias-Paramo , L. K. Hunt , S. Duarte Puertas , G. Ramos-Larios

The Galactic B[e] supergiant MWC 137 is surrounded by a large-scale optical nebula. To shed light on the physical conditions and kinematics of the nebula, we analyze the optical forbidden emission lines [NII] 6548,6583 and [SII] 6716,6731…

Solar and Stellar Astrophysics · Physics 2021-09-29 Michaela Kraus , Tiina Liimets , Alexei Moiseev , Julieta P. Sanchez Arias , Dieter H. Nickeler , Lydia S. Cidale , David Jones

We have imaged the enigmatic radio source-I (Orion-I) in the Orion-KL nebula with the VLA at 43 GHz with 34 mas angular resolution. The continuum emission is highly elongated and is consistent with that expected from a nearly edge-on disk.…

Astrophysics · Physics 2009-06-23 M. J. Reid , K. M. Menten , L. J. Greenhill , C. J. Chandler

We present the result of photo-ionizing modelling of the three planetary nebulae (PNe) A 20, A 15 and MeWe 1-3. All three objects are roughly roundish, highly excited and have a high galactic $z$. The PNe displayed low densities in the…

Astrophysics · Physics 2009-11-10 M. Emprechtinger , T. Rauch , S. Kimeswenger

We report the detection of near-IR H$_2$ emission from the low-ionization structures (knots) in two planetary nebulae. The deepest ever, high-angular resolution H$_2$ 1-0 S(1) at 2.122$\mu$, H$_2$ 2-1 S(1) at 2.248$\mu$ and Br$\gamma$…

Solar and Stellar Astrophysics · Physics 2016-12-21 Stavros Akras , Denise R. Gonçalves , Gerardo Ramos-Larios

The nebular spectra of the energetic Type Ic supernova SN1998bw (hypernova) are studied. The transition to the nebular phase occurred at an epoch of about 100 days after outburst, which is assumed to coincide with GRB980425. Early in the…

Astrophysics · Physics 2016-08-30 P. A. Mazzali , K. Nomoto , F. Patat , K. Maeda

The planetary nebula (PN) NGC 5189 around a Wolf-Rayet [WO] central star demonstrates one of the most remarkable complex morphologies among PNe with many multi-scale structures, showing evidence of multiple outbursts from an AGB progenitor.…

Solar and Stellar Astrophysics · Physics 2018-01-11 Ashkbiz Danehkar , Margarita Karovska , W. Peter Maksym , Rodolfo Montez

The extremely faint, temperature sensitive ``auroral'' emission line [N II] 5755 has been detected from the low density ionized gas along the sight line toward l = 130.0, b = -7.5 using the Wisconsin H-Alpha Mapper (WHAM). The intensity of…

Astrophysics · Physics 2014-10-13 R. J. Reynolds , N. C. Sterling , L. M. Haffner , S. L. Tufte

We report the discovery of a ~100 kpc ionized nebula associated with the radio quiet type 2 quasar (QSO2) nicknamed the "Teacup" (z=0.085). The giant nebula is among the largest known around active galaxies at any z. We propose that it is…

Gemini North adaptive optics imaging spectroscopy is presented for the Galactic ultra-compact HII (UCHII) region K3-50A. Data were obtained in the K-band using the Near-infrared Integral Field Spectrograph (NIFS) behind the facility…

Solar and Stellar Astrophysics · Physics 2015-05-13 Robert D. Blum , Peter J. McGregor

Investigation of spectra from the Sloan Digital Sky Survey reveals the presence of a region of ionized gas of >2 degrees diameter centered approximately at alpha = 10^h 37^m delta = -00^o 18' (J2000) (Galactic coordinates l=248, b=+48).…

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