- ID:
- ivo://CDS.VizieR/J/A+AS/139/277
- Title:
- LMC X-ray sources ROSAT PSPC catalogue
- Short Name:
- J/A+AS/139/277
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We analyzed more than 200 ROSAT PSPC observations in a 10 by 10 degree field centered on the Large Magellanic Cloud (LMC) and performed between 1990 and 1994 to derive a catalogue of X-ray sources. The list contains 758 sources with their X-ray properties. From cross-correlations of the PSPC catalogue with the SIMBAD data base and literature searches we give likely identifications for 144 X-ray sources based on positional coincidence, but taking into account X-ray properties like hardness ratios and source extent. 46 known sources are associated with supernova remnants (SNRs) and candidates in the LMC, most of them already detected by previous X-ray missions.
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Search Results
- ID:
- ivo://CDS.VizieR/J/A+A/609/A114
- Title:
- Local Group AGB stars and red supergiants
- Short Name:
- J/A+A/609/A114
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Mass loss is one of the fundamental properties of asymptotic giant branch (AGB) stars, and through the enrichment of the interstellar medium, AGB stars are key players in the life cycle of dust and gas in the universe. However, a quantitative understanding of the mass-loss process is still largely lacking. To investigate mass loss and luminosity in a large sample of evolved stars in several Local Group galaxies with a variety of metallicities and star-formation histories: the Small and Large Magellanic Cloud, and the Fornax, Carina, and Sculptor dwarf spheroidal galaxies (dSphs). Dust radiative transfer models are presented for 225 carbon stars and 171 oxygen-rich evolved stars in several Local Group galaxies for which spectra from the Infrared Spectrograph on Spitzer are available. The spectra are complemented with available optical and infrared photometry to construct spectral energy distributions. A minimisation procedure is used to determine luminosity and mass-loss rate (MLR). Pulsation periods are derived for a large fraction of the sample based on a re-analysis of existing data. New deep K-band photometry from the VMC survey and multi-epoch data from IRAC (at 4.5 micron) and AllWISE and NEOWISE have allowed us to derive pulsation periods longer than 1000 days for some of the most heavily obscured and reddened objects. We derive (dust) MLRs and luminosities for the entire sample. The estimated MLRs can differ significantly from estimates for the same objects in the literature due to differences in adopted optical constants (up to factors of several) and details in the radiative transfer modelling. Updated parameters for the super-AGB candidate MSX SMC 055 (IRAS 00483-7347) are presented. Its current mass is estimated to be 8.5 +- 1.6 solar mass, suggesting an initial mass well above 8 solar mass in agreement with estimates based on its large Rubidium abundance. Using synthetic photometry, we present and discuss color-color and color-magnitude diagrams which can be expected from the James Webb Space Telescope.
- ID:
- ivo://CDS.VizieR/J/MNRAS/478/3138
- Title:
- Luminous cool supergiants in Magellanic Clouds
- Short Name:
- J/MNRAS/478/3138
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The empirical upper luminosity boundary L_max_ of cool supergiants, often referred to as the Humphreys-Davidson limit, is thought to encode information on the general mass-loss behaviour of massive stars. Further, it delineates the boundary at which single stars will end their lives stripped of their hydrogen-rich envelope, which in turn is a key factor in the relative rates of Type-II to Type-Ibc supernovae from single star channels. In this paper we have revisited the issue of L_max_ by studying the luminosity distributions of cool supergiants (SGs) in the Large and Small Magellanic Clouds (LMC/SMC). We assemble highly-complete samples of cool SGs in each galaxy, and determine their spectral energy distributions from the optical to the mid-infrared using modern multi-wavelength survey data. We show that in both cases L_max_ appears to be lower than previously quoted, and is in the region of logL/L_{sun}_=5.5. There is no evidence for L_max_ being higher in the SMC than in the LMC, as would be expected if metallicity-dependent winds were the dominant factor in the stripping of stellar envelopes. We also show that L_max_ aligns with the lowest luminosity of single nitrogen-rich Wolf-Rayet stars, indicating of a change in evolutionary sequence for stars above a critical mass. From population synthesis analysis we show that the Geneva evolutionary models greatly over-predict the numbers of cool SGs in the SMC. We also argue that the trend of earlier average spectral types of cool SGs in lower metallicity environments represents a genuine shift to hotter temperatures. Finally, we use our new bolometric luminosity measurements to provide updated bolometric corrections for cool supergiants.
- ID:
- ivo://CDS.VizieR/J/ApJ/542/257
- Title:
- MACHO LMC first-overtone RR Lyrae
- Short Name:
- J/ApJ/542/257
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- More than 1300 variables classified provisionally as first-overtone RR Lyrae pulsators in the MACHO variable-star database of the Large Magellanic Cloud (LMC) have been subjected to standard frequency analysis. Based on the remnant power in the prewhitened spectra, we found 70% of the total population to be monoperiodic. The remaining 30% (411 stars) are classified as one of nine types according to their frequency spectra. Several types of RR Lyrae pulsational behavior are clearly identified here for the first time. Together with the earlier discovered double-mode (fundamental and first-overtone) variables, this study increased the number of known double-mode stars in the LMC to 181. During the total 6.5yr time span of the data, 10% of the stars showed strong period changes.
- ID:
- ivo://CDS.VizieR/J/AJ/135/83
- Title:
- MACHO LMC first overtone RR Lyrae
- Short Name:
- J/AJ/135/83
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Previous studies have indicated that many of the RR Lyrae variables in the LMC have properties similar to those in the Galactic globular cluster M3. Assuming that the M3 RR Lyrae variables follow the same relationships among period, temperature, amplitude, and Fourier phase parameter phi31 as their LMC counterparts, we have used the M3 phi31-logP relation to identify the M3-like unevolved first overtone RR Lyrae variables in 16 MACHO fields near the LMC bar.
- ID:
- ivo://CDS.VizieR/J/AJ/127/334
- Title:
- MACHO LMC first-overtone RR Lyrae variables
- Short Name:
- J/AJ/127/334
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Shapes of RR Lyrae light curves can be described in terms of Fourier coefficients that past research has linked with physical characteristics such as luminosity, mass, and temperature. Fourier coefficients have been derived for the V and R light curves of 785 overtone RR Lyrae variables in 16 MACHO fields near the bar of the LMC.
- ID:
- ivo://CDS.VizieR/J/AJ/134/1963
- Title:
- MACHO r,b light curves of MC eclipsing binaries
- Short Name:
- J/AJ/134/1963
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a new sample of 4634 eclipsing binary stars in the Large Magellanic Cloud (LMC), expanding on a previous sample of 611 objects and a new sample of 1509 eclipsing binary stars in the Small Magellanic Cloud (SMC), that were identified in the light-curve database of the MACHO project. We perform a cross-correlation with the OGLE-II LMC sample, finding 1236 matches. A cross correlation with the OGLE-II SMC sample finds 698 matches. We then compare the LMC subsamples corresponding to the center and periphery of the LMC and find only minor differences between the two populations. These samples are sufficiently large and complete that statistical studies of the binary star populations are possible.
308. MACHO Variables V.
- ID:
- ivo://CDS.VizieR/J/AJ/114/326
- Title:
- MACHO Variables V.
- Short Name:
- J/AJ/114/326
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the characteristics of 611 eclipsing binary stars in the Large Magellanic Cloud found by using the MACHO Project photometry database. The sample is magnitude limited, and extends down the main sequence to about spectral type A0. Many evolved binaries are also included. Each eclipsing binary is classified according to the traditional scheme of the General Catalogue of Variable Stars (EA and EB), and also according to a new decimal classification scheme defined in this paper. The new scheme is sensitive to the two major sources of variance in eclipsing binary star light curves -- the sum of radii, and the surface-brightness ratio, and allow greater precision in characterizing the light curves. Examples of each type of light curve and their variations are given. Sixty-four of the eclipsing binaries have eccentric, rather than circular, orbits. The ephemeris and principal photometric characteristics of each eclipsing binary are listed in a table. Photometric orbits based on the Nelson-Davis-Etzel model have been fitted to all light curves. These data will be useful for planning future observations of these binaries. Plots of all data and fitted orbits and a table of the fitted orbital parameters are available on the AAS CD-ROM series, Vol. 9, 1997. These data are also available at the MACHO home page (http://wwwmacho.mcmaster.ca/). (c) 1997 American Astronomical Society.
- ID:
- ivo://CDS.VizieR/J/ApJ/671/1669
- Title:
- Magellanic cloud PNe in the IR
- Short Name:
- J/ApJ/671/1669
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present 5-40um spectroscopy of 41 planetary nebulae (PNe) in the Magellanic Clouds, observed with the Infrared Spectrograph on board the Spitzer Space Telescope. The spectra show the presence of a combination of nebular emission lines and solid state features from dust, superimposed on the thermal IR continuum. By analyzing the 25 LMC and 16 SMC PNe in our sample we found that the IR spectra of 14 LMC and four SMC PNe are dominated by nebular emission lines, while the other spectra show solid state features.
- ID:
- ivo://CDS.VizieR/J/other/PASAu/6.471
- Title:
- Magellanic Clouds bridge region HI profiles
- Short Name:
- J/other/PASAu/6.
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Two hundred and seventeen HI profiles at positions approximately 1degree apart in the bridge region between the Small and Large Magellanic Clouds have been observed with a 15' arc beam. Diagrams of all the profiles, lists of column densities and average radial velocities are given, together with details of the extensive Gaussian analysis needed to account for the components. It is shown that the bridge region is most complex. (a) Two radial velocity (1) groups, +214 and +238km/s, represent the actual HI bridge between the two galaxies. (b) Three other components, at mean radial velocities of +155, +177 and +195km/s are seen to be integral parts of the SMC, stretching east to RA~04h. (c) A further three components in groups at mean radial Velocities +253, +272 and +293km/s appear to be extensions of HI from the main body of the LMC. Nine sets of five closely spaced observations in the lower Magellanic Stream and in the bridge region at high sensitivity supply further information about the region.
