- ID:
- ivo://CDS.VizieR/J/MNRAS/357/645
- Title:
- LMC far-UV HST observations
- Short Name:
- J/MNRAS/357/645
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a new analysis of the deepest pure-ultraviolet (UV) observations with the highest angular resolution ever performed. A set of 12 exposures with the Hubble Space Telescope (HST) WFPC2 and F160BW filter obtained in parallel observing mode, which cover ~12arcmin^2^ in the Large Magellanic Cloud (LMC), north of the bar and in the 'general field' region of the LMC, contain stars with far-UV monochromatic magnitudes as faint as 22mag. The 198 detected UV sources represent an accumulated exposure of 2x10^4^s and reveal stars as faint as m_UV_=~20mag. We combine these observations with deep UBVI charge-coupled device (CCD) imaging of the same region reaching as faint as V=~26mag, and reselect probable optical counterparts for the UV sources. After a two-stage search-and-analysis process, we detect robust counterparts for 129 stars. These are mostly upper main-sequence stars, from early B to early A spectral classes, with several F stars. We point out the lack of blue supergiants, which could have been easily detected in our survey. We measure a foreground extinction E(B-V)=~0.08mag by Galactic dust and a surface density of star formation rate twice the average Galactic value. These observations indicate that relatively recent star formation took place even off the bar of the LMC.
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- ID:
- ivo://CDS.VizieR/J/A+AS/121/247
- Title:
- LMC galactic foreground stars UBV photometry
- Short Name:
- J/A+AS/121/247
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In addition to the list of UBV photometries of 955 galactic foreground stars in the direction to the Large Magellanic Cloud published by Gochermann et al. (1993A&AS...99..591G), a supplement of 545 stars is presented, which have been measured with the same photometric accuracy. Moreover, less reliable photometries of 379 further foreground stars are listed in a separate table. The homogeneous data base of more than 1500 high accuracy photometries represented by these stars has been used to construct a reddening distribution map of the galactic foreground towards the LMC by Oestreicher et al. (1995A&AS..112..495O).
- ID:
- ivo://CDS.VizieR/J/AJ/149/117
- Title:
- LMC infrared survey. I. Photometry of Cepheids
- Short Name:
- J/AJ/149/117
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present observational details and first results of a near-infrared (JHK_s_) synoptic survey of the central region of the Large Magellanic Cloud (LMC) using the CPAPIR camera at the CTIO 1.5m telescope. We covered 18 square degrees to a depth of K_s_~16.5mag and obtained an average of 16 epochs in each band at any given location. Our catalog contains more than 3.5x10^6^ sources, including 1417 Cepheid variables previously studied at optical wavelengths by the OGLE survey. Our sample of fundamental-mode pulsators represents a nine-fold increase in the number of these variables with time-resolved, multi-band near-infrared photometry. We combine our large Cepheid sample and a recent precise determination of the distance to the LMC to derive a robust absolute calibration of the near-infrared Leavitt Law for fundamental-mode and first-overtone Cepheids with 10x better constraints on the slopes relative to previous work. We also obtain calibrations for the tip of the red giant branch and the red clump based on our ensemble photometry which are in good agreement with previous determinations.
- ID:
- ivo://CDS.VizieR/J/AJ/136/1242
- Title:
- LMC long-period variables from MACHO
- Short Name:
- J/AJ/136/1242
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a new analysis of the long-period variables in the Large Magellanic Cloud (LMC) from the MACHO Variable Star Catalog. Three-quarters of our sample of evolved, variable stars have periodic light curves. We characterize the stars in our sample using the multiple periods found in their frequency spectra. Additionally, we use single-epoch Two Micron All Sky Survey measurements to construct the average infrared light curves for different groups of these stars.
- ID:
- ivo://CDS.VizieR/J/AJ/153/154
- Title:
- LMC NIR survey. IV. Type II Cepheid variables
- Short Name:
- J/AJ/153/154
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present time-series observations of Population II Cepheids in the Large Magellanic Cloud at near-infrared (JHK_s_) wavelengths. Our sample consists of 81 variables with accurate periods and optical (VI) magnitudes from the OGLE survey, covering various subtypes of pulsators (BL Herculis, W Virginis, and RV Tauri). We generate light-curve templates using high-quality I-band data in the LMC from OGLE and K_s_-band data in the Galactic bulge from VISTA Variables in Via Lactea survey (2010NewA...15..433M) and use them to obtain robust mean magnitudes. We derive period-luminosity (P-L) relations in the near-infrared and Period-Wesenheit (P-W) relations by combining optical and near-infrared data. Our P-L and P-W relations are consistent with published work when excluding long-period RV Tauris. We find that Pop II Cepheids and RR Lyraes follow the same P-L relations in the LMC. Therefore, we use trigonometric parallax from the Gaia DR1 (Cat. I/337) for VY Pyx and the Hubble Space Telescope parallaxes for k Pav and 5 RR Lyrae variables to obtain an absolute calibration of the Galactic K_s_-band P-L relation, resulting in a distance modulus to the LMC of {mu}_LMC_=18.54+/-0.08 mag. We update the mean magnitudes of Pop II Cepheids in Galactic globular clusters using our light-curve templates and obtain distance estimates to those systems, anchored to a precise late-type eclipsing binary distance to the LMC. We find that the distances to these globular clusters based on Pop II Cepheids are consistent (within 2{sigma}) with estimates based on the M_V_-[Fe/H] relation for horizontal branch stars.
- ID:
- ivo://CDS.VizieR/J/AJ/151/88
- Title:
- LMC NIR Synoptic Survey. II. Wesenheit relations
- Short Name:
- J/AJ/151/88
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new near-infrared (NIR) Cepheid period-Wesenheit (P-W) relations in the LMC using time-series observations from the Large Magellanic Cloud NIR Synoptic Survey. We also derive optical+NIR P-W relations using V and I magnitudes from the Optical Gravitational Lensing Experiment. We employ our new JHK_s_ data to determine an independent distance to the LMC of {mu}_LMC_=18.47+/-0.07 (statistical) mag, using an absolute calibration of the Galactic relations based on several distance determination methods and accounting for the intrinsic scatter of each technique. We also derive new NIR period-luminosity and Wesenheit relations for Cepheids in M31 using observations from the Panchromatic Hubble Andromeda Treasury survey. We use the absolute calibrations of the Galactic and LMC W_J,H_ relations to determine the distance modulus of M31, {mu}_M31_=24.46+/-0.20 mag. We apply a simultaneous fit to Cepheids in several Local Group galaxies covering a range of metallicities (7.7<12+log[O/H]<8.6 dex) to determine a global slope of -3.244+/-0.016 mag/dex for the W_J,H_ relation and obtain robust distance estimates. Our distances are in good agreement with recent TRGB based distance estimates and we do not find any evidence for a metallicity dependence in the NIR P-W relations.
- ID:
- ivo://CDS.VizieR/J/AJ/154/149
- Title:
- LMC NIR synoptic survey. V. NIR photometry of Miras
- Short Name:
- J/AJ/154/149
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study the near-infrared properties of 690 Mira candidates in the central region of the Large Magellanic Cloud, based on time-series observations at JHK_s_. We use densely sampled I-band observations from the OGLE project to generate template light curves in the near-infrared and derive robust mean magnitudes at those wavelengths. We obtain near-infrared Period-Luminosity relations for oxygen-rich Miras with a scatter as low as 0.12 mag at K_s_. We study the Period-Luminosity-Color relations and the color excesses of carbon-rich Miras, which show evidence for a substantially different reddening law.
- ID:
- ivo://CDS.VizieR/J/AcA/63/159
- Title:
- LMC OGLE-III Shallow Survey variable stars
- Short Name:
- J/AcA/63/159
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We describe variable stars found in the data collected during the OGLE-III Shallow Survey covering the I-band magnitude range from 9.7mag to 14.5mag. The main result is the extension of period-luminosity relations for Cepheids up to 134 days. We also detected 82 binary systems and 110 long-period variables not present in the main OGLE catalogs. Additionally 558 objects were selected as candidates for miscellaneous variables.
- ID:
- ivo://CDS.VizieR/J/AcA/62/247
- Title:
- LMC photometric maps from OGLE-III shallow survey
- Short Name:
- J/AcA/62/247
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present photometric maps based on data from the shallow survey in the Large Magellanic Cloud performed as the supplementary project during the third phase of the Optical Gravitational Lensing Experiment (OGLE) . They cover about 40 square degrees in the LMC and contain mean calibrated VI photometry and astrometry of about 1.7million stars. The magnitudes of the objects range from 9.1 to 18.5.
- ID:
- ivo://CDS.VizieR/J/A+A/531/A157
- Title:
- LMC planetary nebulae (VMC Survey II)
- Short Name:
- J/A+A/531/A157
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The VISTA Magellanic Cloud (VMC) survey is assembling a deep, multi-epoch atlas of YJKs photometry across the Magellanic Clouds. Prior to the VMC survey only the brightest Magellanic Cloud PNe (MCPNe) were accessible at near-infrared (NIR) wavelengths. It is now possible for the first time to assemble the NIR properties of MCPNe and to identify contaminating non-PNe mimics which are best revealed at NIR wavelengths (e.g. HII regions and symbiotic stars). To maintain the unique scientific niche that MCPNe occupy these contaminants must be removed. Here we conduct a VMC-led, multi-wavelength study of 102 objects previously classified as PNe that are located within the first six VMC tiles observed. We present images, photometry, lightcurves, diagnostic colour - colour diagrams and spectral energy distributions used to analyse the entire sample. At least five PNe have newly resolved nebula morphologies, a task previously only possible with the HST.
