- ID:
- ivo://CDS.VizieR/J/AJ/142/88
- Title:
- Segue 3 photometric and kinematic data
- Short Name:
- J/AJ/142/88
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate the kinematic and photometric properties of the Segue 3 Milky Way companion using Keck/DEIMOS spectroscopy and Magellan/IMACS g- and r-band imaging. Using maximum likelihood methods to analyze the photometry, we study the structure and stellar population of Segue 3. We find that the half-light radius of Segue 3 is 26"+/-5" (2.1+/-0.4pc, for a distance of 17kpc) and the absolute magnitude is a mere M_V_=0.0+/-0.8mag, making Segue 3 the least luminous old stellar system known.
Number of results to display per page
Search Results
- ID:
- ivo://CDS.VizieR/J/AJ/136/2050
- Title:
- SEGUE stellar parameter pipeline. II.
- Short Name:
- J/AJ/136/2050
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We validate the accuracy and precision of the current SEGUE (Sloan Extension for Galactic Understanding and Exploration) Stellar Parameter Pipeline (SSPP), which determines stellar atmospheric parameters (effective temperature, surface gravity, and metallicity) and radial velocities (RVs), by comparing these estimates for selected members of three globular clusters (M 13, M 15, and M 2) and two open clusters (NGC 2420 and M 67) to the literature values. Spectroscopic and photometric data obtained during the course of the original Sloan Digital Sky Survey (SDSS-I) and its first extension (SDSS-II/SEGUE) are used to determine atmospheric parameter and RV estimates for stars in these clusters.
- ID:
- ivo://CDS.VizieR/J/AJ/141/89
- Title:
- SEGUE stellar parameter pipeline. IV.
- Short Name:
- J/AJ/141/89
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Spectroscopic and photometric data for likely member stars of five Galactic globular clusters (M3, M53, M71, M92, and NGC 5053) and three open clusters (M35, NGC 2158, and NGC 6791) are processed by the current version of the SEGUE Stellar Parameter Pipeline (SSPP), in order to determine estimates of metallicities and radial velocities (RVs) for the clusters. These results are then compared to values from the literature.
5904. Segue 3 VI photometry
- ID:
- ivo://CDS.VizieR/J/MNRAS/433/1966
- Title:
- Segue 3 VI photometry
- Short Name:
- J/MNRAS/433/1966
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Deep Galileo (Telescopio Nazionale Galileo) B, V and I images of Segue 3, reaching V~25, reveal that it is the youngest globular cluster known so far in the Galaxy. A young age of 3.2Gyr is found, differently from a previous estimate of 12Gyr. It also appears to be moderately metal rich with [Fe/H]~-0.8, rather than [Fe/H]~-1.7, as previously suggested by Fadely et al. (2011AJ....142...88F, Cat. J/AJ/142/88). A main difference in the age derivation relative to Fadely et al. comes from the consideration of subgiant branch stars in the isochrone fitting. A deduced distance of d_{sun}_=29.1kpc is compatible with the outer halo location of other low luminosity globular clusters.
- ID:
- ivo://CDS.VizieR/J/A+A/597/A30
- Title:
- Seismology and spectroscopy of CoRoGEE red giants
- Short Name:
- J/A+A/597/A30
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the CoRoGEE dataset -- obtained from CoRoT lightcurves for 606 red giant stars in two fields of the Galactic disc which have been co-observed for an ancillary project of the Apache Point Observatory Galactic Evolution Experiment (APOGEE). The CoRoGEE stars cover a large radial range of the Milky Way's disc (5kpc<RGal<14kpc) and thus provide a valuable dataset for Galactic Archaeology studies. We have used the Bayesian parameter estimation code PARAM to calculate distances, extinctions, masses, and ages for these stars in a homogeneous analysis, resulting in relative statistical uncertainties of 2% in distance, 4% in radius, ~9% in mass and ~25% in age. We also assess systematic age uncertainties due to different input physics and mass loss.
- ID:
- ivo://CDS.VizieR/J/A+AS/112/367
- Title:
- Selected Regions C and E in the LMC
- Short Name:
- J/A+AS/112/367
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present CCD data of objects in the LMC selected regions C and E. These data include the young globular cluster NGC 1818, the association NGC 1948 and the intermediate age cluster NGC 1978. We discuss the calibration of the data and provide complete tables of the photometry and astrometry of all stars within our field of view.
- ID:
- ivo://CDS.VizieR/J/A+A/656/A66
- Title:
- Semi-regular red giants as distance indicators
- Short Name:
- J/A+A/656/A66
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- Semi-regular variables (SRVs) are similar to Miras in brightness, and they also follow PLRs, though not necessarily the same as Miras. As potential standard candles they are more challenging than Miras due to their smaller variability amplitudes and less regular light curves, but they are substantially more numerous and especially promising to probe old stellar populations. We aim to characterize the variability of SRVs, with focus on their connection with Miras, in order to prepare the ground for investigating their potential as distance indicators. We examine SRVs and Miras in the Magellanic Clouds from OGLE-III observations, with data from Gaia and 2MASS. After cleaning the sample from variability periods unrelated to pulsation, we classify each source by chemical type and combination of pulsation modes. We examine the results in terms of global photometric and pulsation properties. We identify four SRVs groups that fit the general evolutionary scenario predicted by theory. SRVs dominated by fundamental-mode pulsation are very similar to Miras, especially if mono-periodic. They further split into two sub-groups, one of which follows the same sequence as Miras in the period-luminosity and period-amplitude diagram, without discontinuity. The similarities between Miras and SRVs suggest that the latter can be adopted as complementary distance indicators to the former, thereby at least doubling the available number of LPVs suitable for use as distance indicators. The traditional amplitude-based separation between Miras and SRVs is not necessarily appropriate, and a more physically sound criterion should also involve pulsation periods. While this would require comparatively longer time series, they are expected to become accessible in the coming years even for weak sources thanks to current and future large-scale surveys. The table of reclassified LPVs is made public.
- ID:
- ivo://CDS.VizieR/J/ApJ/552/289
- Title:
- Semiregular variable stars in Baade's windows
- Short Name:
- J/ApJ/552/289
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- By cross-correlating the results of two recent large-scale surveys, the general properties of a well-defined sample of semiregular variable stars have been determined. ISOGAL mid-infrared photometry (7 and 15{mu}m and MACHO V and R light curves are assembled for approximately 300 stars in the Baade's windows of low extinction toward the Galactic bulge. These stars are mainly giants of late M spectral type, evolving along the asymptotic giant branch (AGB). They are found to possess a wide and continuous distribution of pulsation periods and to obey an approximate logP-M_bol_ relation or set of such relations.
- ID:
- ivo://CDS.VizieR/J/A+A/555/A63
- Title:
- Semi-sinusoidal variability with CoRoT
- Short Name:
- J/A+A/555/A63
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- To date, the CoRoT space mission has produced more than 124471 light curves. Classifying these curves in terms of unambiguous variability behavior is mandatory for obtaining an unbiased statistical view on their controlling root-causes. The present study provides an overview of semi-sinusoidal light curves observed by the CoRoT exo-field CCDs. We selected a sample of 4206 light curves presenting well-defined semi-sinusoidal signatures. The variability periods were computed based on Lomb-Scargle periodograms, harmonic fits, and visual inspection.
- ID:
- ivo://CDS.VizieR/J/MNRAS/453/3729
- Title:
- Sersic + exponential disc morphologies in Coma
- Short Name:
- J/MNRAS/453/3729
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Galaxies are not limited to simple spheroid or bulge + disc morphologies. We explore the diversity of internal galaxy structures in the Coma Cluster across a wide range of luminosities (-17>Mg>-22) and cluster-centric radii (0<r_cluster_<1.3r_200_) through analysis of deep Canada-France-Hawaii Telescope i-band imaging. We present 2D multicomponent decomposition via galfit, encompassing a wide range of candidate model morphologies with up to three photometric components. Particular focus is placed on early-type galaxies with outer discs (i.e. S0s), and deviations from simple ('unbroken') exponential discs. Rigorous filtering ensures that each model component provides a statistically significant improvement to the goodness-of-fit. The majority of Coma Cluster members in our sample (478 of 631) are reliably fitted by symmetric structural models. Of these, 134 (28 percent) are single Sersic objects, 143 (30 percent) are well-described by 2-component structures, while 201 (42 percent) require more complex models. Multicomponent Sersic galaxies resemble compact pseudo-bulges (n~2, R_e_~4kpc) surrounded by extended Gaussian-like outer structures (R_e_>10kpc). 11 percent of galaxies (N=52) feature a break in their outer profiles, indicating 'truncated' or 'antitruncated' discs. Beyond the break radius, truncated galaxies are structurally consistent with exponential discs, disfavouring physical truncation as their formation mechanism. Bulge luminosity in antitruncated galaxies correlates strongly with galaxy luminosity, indicating a bulge-enhancing origin for these systems. Both types of broken disc are found overwhelmingly (>70 percent) in 'barred' galaxies, despite a low measured bar fraction for Coma (20+/-2 percent). Thus, galaxy bars play an important role in formation of broken disc structures. No strong variation in galaxy structure is detected with projected cluster-centric radius.