Related papers: Stellar spectroscopy far beyond the Local Group
We present BV photometry for 54 variables in the metal-rich inner halo globular cluster NGC6723. With the discovery of new RR Lyrae variables (RRLs), we obtain <P_ab> = 0.541 +/- 0.066 and <P_c> = 0.292 +/- 0.030 day, n(c)/n(ab+c) = 0.167,…
We reveal the stellar light emerging from the kiloparsec-scale, ring-like structure of the NGC5128 (Centaurus A) galaxy in unprecedented detail. We use arcsecond-scale resolution near infrared images to create a "dust-free" view of the…
Despite a resurgence of effort over the last decade in the area of massive stars there is still ambiguity over their evolutionary path, contamination of their surface abundances and the behaviour of their stellar winds. Here 10 SMC B-type…
By combining the photometric, spectroscopic, and astrometric information of the stars in the sightline of SNRs, the distances to and the extinctions of 32 Galactic supernova remnants (SNRs) are investigated. The stellar atmospheric…
We have derived elemental abundances of a remarkable star, HD 179821, with unusual composition (e.g. [Na/Fe]=1.0$\pm$0.2 dex) and extra-ordinary spectral characteristics. Its metallicity at [Fe/H]=0.4 dex places it among the most metal-rich…
We present FUSE spectroscopy and supporting data for star-forming regions in nearby galaxies, to examine their massive-star content and explore the use of abundance and population indicators in this spectral range for high-redshift…
We have observed a sample of 35 long-period variables and four Cepheid variables in the vicinity of 23 Galactic globular clusters using the Infrared Spectrograph on the Spitzer Space Telescope. The long-period variables in the sample cover…
The outer region (0.75--1.25 r_e in the B-band) of the merger-remnant elliptical NGC 3610 is studied using extremely high signal to noise Keck spectra, with a supplementary spectrum of the galaxy center. Stellar population parameters --…
We present results of Gemini spectroscopy and Hubble Space Telescope imaging of the 3C~381 radio galaxy. Possible ionising mechanisms for the Extended Emission-Line Region were studied through state-of-the-art diagnostic analysis employing…
HST-WFPC2 F555W and F814W photometry were obtained for 16 fields of the luminous nearby spiral galaxy M31, sampling the stellar content of the disk and the halo at different distances from the center, from ~ 20 to ~ 150 arcmin (i.e. ~ 4.5…
Optical emission lines across the Small Magellanic Cloud (SMC) have been measured from multiple fields using the Australian National University (ANU) 2.3m telescope with the Wide-Field Spectrograph (WiFeS). Interpolated maps of the…
The results from deep long-slit spectroscopy of nine edge-on spiral galaxies with known extraplanar line emission are reported. Emission from Halpha, [N II] lambda 6548, 6583, and [S II] lambda 6716, 6731 is detected out to heights of a few…
We explore the nature of variations in dust emission within an individual galaxy using 3.6 - 160 micron Spitzer Space Telescope observations and 450 and 850 micron James Clerk Maxwell Telescope observations of the edge-on Sd spiral galaxy…
We present for the first time infrared observations of the nearby highly obscured galaxy Dwingeloo 1 (Dw1), including deep H-band imaging covering a total of 4.9x4.9 arcmin, together with J and Ks imaging of the central 2.5x2.5 arcmin. We…
The infrared spectra of starburst galaxies are dominated by the low-excitation lines of [NeII] and [SIII], and the stellar populations deduced from these spectra appear to lack stars larger than about 35 Msun. The only exceptions to this…
We present spectroscopy of nine planetary nebulae (PNe) in the outskirts of M31, all but one obtained with the 10.4m GTC telescope. These sources extend our previous study of the oxygen abundance gradient of M31 to galactocentric radii as…
Given the complex nature of galaxies' interstellar medium (ISM), multi-wavelength data are required to probe the interplay among gas, dust, and stellar populations. Spiral galaxies are ideal laboratories for such a goal as they are rich in…
NGC 6441 is a bulge globular cluster with an unusual horizontal branch morphology and a rich population of RR Lyrae (RRL) and Type II Cepheid (T2C) variables that is unexpected for its relatively high metallicity. We present near-infrared…
Blue supergiants (BSGs) are key objects for understanding the evolution of massive stars. However, discrepancies between theoretical predictions and empirical observations have opened up important questions yet to be answered. Studying…
An explanation is given of the low value of $R_\lambda \equiv A_\lambda/E(B-V) $, the ratio of absolute to selective extinction deduced from Type Ia supernova observations. The idea involves scattering by dust clouds located in the…