Search

Start Over Subject photometry Capability Type Simple Cone Search
4521. Solar neighbourhood metallicity distribution
ID:
ivo://CDS.VizieR/J/MNRAS/325/1365
Title:
Solar neighbourhood metallicity distribution
Short Name:
J/MNRAS/325/1365
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a revised metallicity distribution of dwarfs in the solar neighbourhood. This distribution is centered on solar metallicity. We show that previous metallicity distributions, selected on the basis of spectral type, are biased against stars with solar metallicity or higher. A selection of G-dwarf stars is inherently biased against metal-rich stars and is not representative of the solar neighbourhood metallicity distribution. Using a sample selected on colour, we obtain a distribution where approximately half the stars in the solar neighbourhood have metallicities higher than [Fe/H]=0. The percentage of mid-metal-poor stars ([Fe/H}<-0.5) is approximately 4 per cent, in agreement with the present estimates of the thick disc.
4522. Sombrero galaxy globular clusters
ID:
ivo://CDS.VizieR/J/MNRAS/417/1823
Title:
Sombrero galaxy globular clusters
Short Name:
J/MNRAS/417/1823
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a large sample of over 200 integrated-light spectra of confirmed globular clusters (GCs) associated with the Sombrero (M104) galaxy taken with the Deep Imaging Multi-Object Spectrograph (DEIMOS) instrument on the Keck telescope. A significant fraction of the spectra have signal-to-noise ratio levels high enough to allow measurements of GC metallicities using the method of Brodie & Huchra. We find a distribution of spectroscopic metallicities in the range -2.2<[Fe/H]<+0.1 that is bimodal, with peaks at [Fe/H]~-1.4 and -0.6. Thus, the GC system of the Sombrero galaxy, like a few other galaxies now studied in detail, reveals a bimodal spectroscopic metallicity distribution supporting the long-held belief that colour bimodality reflects two metallicity subpopulations. This further suggests that the transformation from optical colour to metallicity for old stellar populations, such as GCs, is not strongly non-linear. We also explore the radial and magnitude distribution with metallicity for GC subpopulations but small number statistics prevent any clear trends in these distributions.
4523. SONYC census of substellar objects in Lupus 3
ID:
ivo://CDS.VizieR/J/ApJ/785/159
Title:
SONYC census of substellar objects in Lupus 3
Short Name:
J/ApJ/785/159
Date:
21 Oct 2021
Publisher:
CDS
Description:
SONYC -Substellar Objects in Nearby Young Clusters- is a survey program to investigate the frequency and properties of substellar objects in nearby star-forming regions. We present a new imaging and spectroscopic survey conducted in the young (~1 Myr), nearby (~200 pc) star-forming region Lupus 3. Deep optical and near-infrared images were obtained with MOSAIC-II and NEWFIRM at the CTIO 4 m telescope, covering ~1.4 deg^2^ on the sky. The i-band completeness limit of 20.3 mag is equivalent to 0.009-0.02 M_{sun}_, for A_V_<=5. Photometry and 11-12 yr baseline proper motions were used to select candidate low-mass members of Lupus 3. We performed a spectroscopic follow-up of 123 candidates, using VIMOS at the Very Large Telescope, and we identify 7 probable members, among which 4 have spectral type later than M6.0 and T_eff_<=3000 K, i.e., are probably substellar in nature. Two of the new probable members of Lupus 3 appear underluminous for their spectral class and exhibit emission line spectrum with strong H_{alpha}_ or forbidden lines associated with active accretion. We derive a relation between the spectral type and effective temperature: T_eff_=(4120+/-175)-(172+/-26)xSpT, where SpT refers to the M spectral subtype between 1 and 9. Combining our results with the previous works on Lupus 3, we show that the spectral type distribution is consistent with that in other star-forming regions, as well as the derived star-to-brown dwarf ratio of 2.0-3.3. We compile a census of all spectroscopically confirmed low-mass members with spectral type M0 or later.
4524. SONYC census of very low-mass objects in NGC1333
ID:
ivo://CDS.VizieR/J/ApJ/744/6
Title:
SONYC census of very low-mass objects in NGC1333
Short Name:
J/ApJ/744/6
Date:
21 Oct 2021
Publisher:
CDS
Description:
SONYC - Substellar Objects in Nearby Young Clusters - is a program to investigate the frequency and properties of young substellar objects with masses down to a few times that of Jupiter. In a series of papers we have obtained follow-up spectroscopy for a large number of candidate very low mass (VLM) members of the ~1Myr old cluster NGC1333 in the Perseus star forming region. For more details on the survey, see the associated paper (Scholz et al., 2012ApJ...744....6S). Here we present a census of spectroscopically confirmed very low mass objects in NGC1333. We include all objects with spectral type of M5 or later and/or effective temperature of 3200K or cooler. In total, there are now 58 objects which fulfill these criteria. In three tables we list photometric and spectroscopic properties for our own sample as well as for objects listed in the literature. In addition, we also include three tables of the objects that have been rejected as very low mass cluster members based on our spectroscopic follow-up. Finally, we attach the two photometric candidate lists from which the spectroscopic sample was extracted, see Scholz et al. (2012ApJ...756...24S) for more details on these catalogues.
4525. SONYC new brown dwarfs in {rho} Oph
ID:
ivo://CDS.VizieR/J/ApJ/744/134
Title:
SONYC new brown dwarfs in {rho} Oph
Short Name:
J/ApJ/744/134
Date:
21 Oct 2021
Publisher:
CDS
Description:
SONYC - Substellar Objects in Nearby Young Clusters - is a survey program to investigate the frequency and properties of substellar objects with masses down to a few times that of Jupiter in nearby star-forming regions. In two papers of the SONYC series we have obtained follow-up spectroscopy for a large number of candidate very low ma ss (VLM) members of the ~1Myr old cluster rho Ophiuchi. For more details on the survey, see the associated paper (Muzic et al., 2012ApJ...744..134M). Here we publish the two catalogues of photometric candidate members from which the spectroscopic samples were extracted (see Geers et al. 2011ApJ...726...23G and Muzic et al. 2012ApJ...744..134M for more details on these catalogues). We include a table containing all the spectroscopically confirmed VLM members of the cluster observed within the SONYC campaign. We also attach and a table with all the objects that have been rejected as VLM members based on our spectroscopic follow-up. The majority of these latter objects are expected to be background contaminants, although some of them could also be embedded cluster members with spectral types earlier than M.
4526. Sources around target stars in Upper Scorpius
ID:
ivo://CDS.VizieR/J/ApJ/785/47
Title:
Sources around target stars in Upper Scorpius
Short Name:
J/ApJ/785/47
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of a multiplicity survey of 91 stars spanning masses of ~0.2-10 M_{sun}_ in the Upper Scorpius star-forming region, based on adaptive optics imaging with the Gemini North telescope. Our observations identified 29 binaries, 5 triples, and no higher order multiples. The corresponding raw multiplicity frequency is 0.37+/-0.05. In the regime where our observations are complete - companion separations of 0.1''-5'' (~15-800 AU) with magnitude limits ranging from K <9.3 at 0.1'' to K<15.8 at 5'' - the multiplicity frequency is 0.27_0.04_^+0.05^. For similar separations, the multiplicity frequency in Upper Scorpius is comparable to that in other dispersed star-forming regions, but is a factor of two to three higher than in denser star-forming regions or in the field. Our sample displays a constant multiplicity frequency as a function of stellar mass. Among our sample of binaries, we find that both wider (>100 AU) and higher-mass systems tend to have companions with lower companion-to-primary mass ratios. Three of the companions identified in our survey are unambiguously substellar and have estimated masses below 0.04 M_{sun}_ (two of them are new discoveries from this survey - 1RXS J160929.1-210524b and HIP 78530B - although we have reported them separately in earlier papers). These three companions have projected orbital separations of 300-900 AU. Based on a statistical analysis factoring in sensitivity limits, we calculate an occurrence rate of 5-40 M_Jup_ companions of ~4.0% for orbital separations of 250-1000 AU, compared to <1.8% at smaller separations, suggesting that such companions are more frequent on wider orbits.
4527. Southern catalogue of isolated pairs extension
ID:
ivo://CDS.VizieR/J/other/ApL/30.1
Title:
Southern catalogue of isolated pairs extension
Short Name:
J/other/ApL/30.1
Date:
21 Oct 2021
Publisher:
CDS
Description:
The paper presents a sample of double galaxies selected from The Surface Photometry Catalog of the ESO-Uppsala Galaxies (Cat. <VII/115>) using the Karachentsev (1972: K72, Cat. <VII/77>) criteria. Considering the large and growing number of observing facilities in that hemisphere, the sample aims to supply investigators with targets as homogeneous as possible to those in the Northern Catalog of Isolated Pairs of Galaxies (K72) which have been studied in a large frequency range. The paper discusses the sample degree of completeness, separation and velocity distributions. First inferences are sketched from the morphological association of pair members and from the study of the Holmberg effect. Being the primary purpose of the paper to provide a tool to investigators, an Atlas of images for the 301 best candidate pairs obtained using the Digitized Sky Survey (The Digitized Sky Survey was produced at the Space Telescope Science Institute (ST ScI) under U.S. Government grant NAG W-2166) is given. The Atlas reports for each pair member the relevant data as obtained from the current literature.
4528. Southern emission-line stars multiphotometry
ID:
ivo://CDS.VizieR/J/A+A/380/609
Title:
Southern emission-line stars multiphotometry
Short Name:
J/A+A/380/609
Date:
21 Oct 2021
Publisher:
CDS
Description:
This paper presents a catalogue of previously unpublished optical and infrared photometry for a sample of 162 emission-line objects and shell stars visible from the southern hemisphere. The data were obtained between 1978 and 1997 in the Walraven (WULBV), Johnson/Cousins UBV(RI)_c_ and ESO and SAAO near-infrared (JHKLM) photometric systems. Most of the observed objects are Herbig Ae/Be (HAeBe) stars or HAeBe candidates appearing in the list of HAeBe candidates of The et al. (1994, Cat. <J/A+AS/104/315>), although several B[e] stars, LBVs and T Tauri are also included in the sample. For many of the stars the data presented here are the first photo-electric measurements in the literature. The resulting catalogue consists of 1809 photometric measurements. Optical variability was detected in 66 out of the 116 sources that were observed more than once. 15 out of the 50 stars observed multiple times in the infrared showed variability at 2.2 microns (K band). Table 1 contains the stars identifiers, positions, types and a summary of the observational data on each star. Tables 2, 3 and 4 contain all obtained photometry in the Walraven WULBV, Johnson/Cousins UBV(RI)_c and ESO and SAAO near-infrared (JHKLM) photometric systems.
4529. Southern Galactic Be star candidates
ID:
ivo://CDS.VizieR/J/PASP/126/219
Title:
Southern Galactic Be star candidates
Short Name:
J/PASP/126/219
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the result of a search for southern Galactic Be star candidates within the group of miscellaneous variables of the ASAS-2 catalog of variable stars, using statistical, morphological, photometric, and color criteria. This search lead us to obtain a catalog of 213 new Be star candidates. The I-band light curves of these candidates show outbursts (Type-1 stars) only in 9% of the sample, and stochastic variations (Type-4 stars) in 91% of the sample. We do not find stars showing clear high and low states (Type-2 stars) or showing outbursts and high and low states simultaneously (Type-1/Type-2 stars). Our sample of southern Galactic Be star candidates provide valuable new bright targets for high resolution spectroscopic studies with small/medium size telescopes.
4530. Southern Infrared Proper Motion Survey
ID:
ivo://CDS.VizieR/J/A+A/435/363
Title:
Southern Infrared Proper Motion Survey
Short Name:
J/A+A/435/363
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the first results from the Southern Infrared Proper Motion Survey. Using 2 Micron All Sky Survey (<II/246>) data along with that of the SuperCOSMOS sky survey (Hambly et al., 2001MNRAS.326.1279H) we have been able to produce the first widefield infrared proper motion survey. Having targeted the survey to identify nearby M, L and T dwarfs we have discovered 70 such new objects with proper motions greater than 0.5"/yr with 10 of these having proper motions in excess of 1"/yr.