- ID:
- ivo://CDS.VizieR/J/AJ/117/206
- Title:
- LMC far-ultraviolet imaging
- Short Name:
- J/AJ/117/206
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an analysis of the deepest pure UV observations with the highest angular resolution ever performed, a set of 12 exposures with the Hubble Space Telescope (HST) Wide Field Planetary Camera 2 and F160BW filter obtained in parallel observing mode, which covers ~12arcmin^2^ in the Large Magellanic Cloud (LMC), north of the bar, and in the "general field" regime of the LMC. The 341 independent measurements of 198 objects represent an accumulated exposure of >=2x10^4^s and reveal stars as faint as m_UV_~=22mag. The observations show that about two-thirds of the UV emission from the LMC is emitted by our HST-detected UV stars in the field, that is, not in clusters or associations. We identified optical counterparts in the Royal Observatory Edinburgh/Naval Research Laboratory photometric catalog for about one-third of the objects.
Number of results to display per page
Search Results
- 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.
263. LMC F supergiants
- ID:
- ivo://CDS.VizieR/J/A+A/293/347
- Title:
- LMC F supergiants
- Short Name:
- J/A+A/293/347
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- (no description available)
- 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/A+A/586/A71
- Title:
- LMC 0.2-100GeV images
- Short Name:
- J/A+A/586/A71
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The nearby Large Magellanic Cloud (LMC) provides a rare opportunity of a spatially resolved view of an external star-forming galaxy in {gamma}-rays. The LMC was detected at 0.1-100GeV as an extended source with CGRO/EGRET and using early observations with the Fermi-LAT. The emission was found to correlate with massive star-forming regions and to be particularly bright towards 30 Doradus. Studies of the origin and transport of cosmic rays (CRs) in the Milky Way are frequently hampered by line-of-sight confusion and poor distance determination. The LMC offers a complementary way to address these questions by revealing whether and how the {gamma}-ray emission is connected to specific objects, populations of objects, and structures in the galaxy. We revisited the {gamma}-ray emission from the LMC using about 73 months of Fermi-LAT P7REP data in the 0.2-100GeV range. We developed a complete spatial and spectral model of the LMC emission, for which we tested several approaches: a simple geometrical description, template-fitting, and a physically driven model for CR-induced interstellar emission.
- ID:
- ivo://CDS.VizieR/J/AJ/140/328
- Title:
- LMC High-amplitude delta Scuti stars
- Short Name:
- J/AJ/140/328
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present 2323 high-amplitude {delta}-Scuti (HADS) candidates discovered in the Large Magellanic Cloud by the SuperMACHO survey (Rest et al., 2005ApJ...634.1103R). Frequency analyses of these candidates reveal that several are multimode pulsators, including 119 whose largest amplitude of pulsation is in the fundamental (F) mode and 19 whose largest amplitude of pulsation is in the first overtone (FO) mode.
- 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/A+A/655/A12
- Title:
- LMC N113 and N159W ALMA para-H_2_CO datacubes
- Short Name:
- J/A+A/655/A12
- Date:
- 07 Mar 2022 07:15:12
- Publisher:
- CDS
- Description:
- We mapped the kinetic temperature structure of two massive star-forming regions, N113 and N159W, in the Large Magellanic Cloud (LMC). We have used ~1.6" (~0.4pc) resolution measurements of the para-H_2_CO J_KaKc_=3_03_-2_02_, 3_22_-2_21_, and 3_21_-2_20_ transitions near 218.5GHz to constrain RADEX non local thermodynamic equilibrium models of the physical conditions. The gas kinetic temperatures derived from the para-H_2_CO line ratios 3_22_-2_21_/3_03_-2_02_ and 3_21_-2_20_/3_03_-2_02_ range from 28 to 105K in N113 and 29 to 68K in N159W. Distributions of the dense gas traced by para-H_2_CO agree with those of the 1.3mm dust and Spitzer 8.0um emission, but they do not significantly correlate with the H emission. The high kinetic temperatures (T_kin_>~50K) of the dense gas traced by para-H_2_CO appear to be correlated with the embedded infrared sources inside the clouds and/or young stellar objects in the N113 and N159W regions. The lower temperatures (T_kin_<50K) were measured at the outskirts of the H_2_CO-bearing distributions of both N113 and N159W. It seems that the kinetic temperatures of the dense gas traced by para-H_2_CO are weakly affected by the external sources of the H{alpha} emission. The non thermal velocity dispersions of para-H_2_CO are well correlated with the gas kinetic temperatures in the N113 region, implying that the higher kinetic temperature traced by para-H_2_CO is related to turbulence on a ~0.4pc scale. The dense gas heating appears to be dominated by internal star formation activity, radiation, and/or turbulence. It seems that the mechanism heating the dense gas of the star-forming regions in the LMC is consistent with that in Galactic massive star-forming regions located in the Galactic plane.
- 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.
