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2241. Multiphotometry of NGC 6611
ID:
ivo://CDS.VizieR/J/A+AS/121/223
Title:
Multiphotometry of NGC 6611
Short Name:
J/A+AS/121/223
Date:
21 Oct 2021
Publisher:
CDS
Description:
For the search of Herbig Ae/Be objects in the extremely young open cluster NGC 6611 we have selected a sample of 52 pre-main sequence candidates, discovered by Walker (1961ApJ...133..438W), Sagar & Joshi (1979Ap&SS..66....3S), Chini & Wargau (1990A&A...227..213C) and The et al. (1990A&AS...82..319T). We continue the approach of the last paper by studying each star individually with new and unpublished Walraven WULBV, Johnson/Cousins UBV(RI)_C_ and Johnson JHKLM photometric data as well as low resolution spectroscopy. For a description of the Walraven, UBVRI, IJHKLMN and RI Cousins photometric systems, see e.g. <GCPD/11>, <GCPD/08>, <GCPD/09> and <GCPD/54>
2242. Multiple M dwarf stars with Robo-AO and Gaia DR2
ID:
ivo://CDS.VizieR/J/AJ/159/139
Title:
Multiple M dwarf stars with Robo-AO and Gaia DR2
Short Name:
J/AJ/159/139
Date:
21 Oct 2021
Publisher:
CDS
Description:
We analyze observations from Autonomous laser-adaptive-optics for few-meter-class telescopes (Robo-AO)'s field M dwarf survey taken on the 2.1m Kitt Peak telescope and perform a multiplicity comparison with Gaia DR2. Through its laser-guided, automated system, the Robo-AO instrument has yielded the largest adaptive optics M dwarf multiplicity survey to date. After developing an interface to visually identify and locate stellar companions, we selected 11 low-significance Robo-AO detections for follow-up on the Keck II telescope using NIRC2. In the Robo-AO survey we find 553 candidate companions within 4" around 534 stars out of 5566 unique targets, most of which are new discoveries. Using a position cross-match with DR2 on all targets, we assess the binary recoverability of Gaia DR2 and compare the properties of multiples resolved by both Robo-AO and Gaia. The catalog of nearby M dwarf systems and their basic properties presented here can assist other surveys which observe these stars, such as the NASA Transiting Exoplanet Survey Satellite (TESS) mission.
2243. Multiple systems:relative positions and residuals
ID:
ivo://CDS.VizieR/J/AJ/155/160
Title:
Multiple systems:relative positions and residuals
Short Name:
J/AJ/155/160
Date:
21 Oct 2021
Publisher:
CDS
Description:
This paper draws attention to the class of resolved triple stars with moderate ratios of inner and outer periods (possibly in a mean motion resonance) and nearly circular, mutually aligned orbits. Moreover, stars in the inner pair are twins with almost identical masses, while the mass sum of the inner pair is comparable to the mass of the outer component. Such systems could be formed either sequentially (inside-out) by disk fragmentation with subsequent accretion and migration, or by a cascade hierarchical fragmentation of a rotating cloud. Orbits of the outer and inner subsystems are computed or updated in four such hierarchies: LHS 1070 (GJ 2005, periods 77.6 and 17.25 years), HIP 9497 (80 and 14.4 years), HIP 25240 (1200 and 47.0 years), and HIP 78842 (131 and 10.5 years).
2244. Multiplicity among peculiar A stars I.
ID:
ivo://CDS.VizieR/J/A+AS/130/223
Title:
Multiplicity among peculiar A stars I.
Short Name:
J/A+AS/130/223
Date:
21 Oct 2021
Publisher:
CDS
Description:
Radial velocities measured with the Coravel scanner are used to determine the orbits of two Ap stars and of two Am stars. The Ap stars HD 8441 appears to be a triple system (though of SB1 type), while improved orbital elements and masses are given for the classical Ap star beta CrB. Both Am stars HD 43478 and HD 93961 are SB2 binaries, and the fundamental elements of the former can be known thanks to its eclipsing nature.
2245. Multiplicity in transiting planet-host stars
ID:
ivo://CDS.VizieR/J/A+A/546/A10
Title:
Multiplicity in transiting planet-host stars
Short Name:
J/A+A/546/A10
Date:
21 Oct 2021
Publisher:
CDS
Description:
In the exoplanetary era, the Kepler spacecraft is causing a revolution by discovering thousands of new planet candidates. However, a follow-up program is needed to reject false candidates and fully characterize the bona-fide exoplanets. Our main aims are to 1./ detect and analyze close companions inside the typical Kepler point spread function (PSF) to study whether they are the responsible for the dimming found in Kepler light curves, 2./ study the change in the stellar and planetary parameters caused by an unresolved object, 3./ help validate the Kepler objects of interest (KOI) that do not have any object inside the Kepler PSF, and 4./ study the multiplicity rate of planet-host candidates. Such a large sample of observed planet-host candidates allows us to derive statistics for close (visual or bounded) companions to the harboring star.
2246. Multiply imaged supernova Refsdal
ID:
ivo://CDS.VizieR/J/ApJ/817/60
Title:
Multiply imaged supernova Refsdal
Short Name:
J/ApJ/817/60
Date:
21 Oct 2021
Publisher:
CDS
Description:
Supernova "Refsdal", multiply imaged by cluster MACS1149.5+2223, represents a rare opportunity to make a true blind test of model predictions in extragalactic astronomy, on a timescale that is short compared to a human lifetime. In order to take advantage of this event, we produced seven gravitational lens models with five independent methods, based on Hubble Space Telescope (HST) Hubble Frontier Field images, along with extensive spectroscopic follow-up observations by HST, the Very Large and the Keck Telescopes. We compare the model predictions and show that they agree reasonably well with the measured time delays and magnification ratios between the known images, even though these quantities were not used as input. This agreement is encouraging, considering that the models only provide statistical uncertainties, and do not include additional sources of uncertainties such as structure along the line of sight, cosmology, and the mass sheet degeneracy. We then present the model predictions for the other appearances of supernova "Refsdal". A future image will reach its peak in the first half of 2016, while another image appeared between 1994 and 2004. The past image would have been too faint to be detected in existing archival images. The future image should be approximately one-third as bright as the brightest known image (i.e., H_AB_~25.7mag at peak and H_AB_~26.7mag six months before peak), and thus detectable in single-orbit HST images. We will find out soon whether our predictions are correct.
2247. Multisite UBVRI photometry in Tau-Aur cloud
ID:
ivo://CDS.VizieR/J/A+AS/101/485
Title:
Multisite UBVRI photometry in Tau-Aur cloud
Short Name:
J/A+AS/101/485
Date:
21 Oct 2021
Publisher:
CDS
Description:
(no description available)
2248. Multiwavelength analysis of NGC 2362
ID:
ivo://CDS.VizieR/J/ApJ/646/269
Title:
Multiwavelength analysis of NGC 2362
Short Name:
J/ApJ/646/269
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a multi-wavelength analysis of the young open cluster NGC 2362; UBVRcIc CCD photometric observations, together with available data in the Chandra database, near-infrared data from the Two Micron All Sky Survey (2MASS), and recently published H{alpha} spectroscopy were used to get information about the evolutionary stage of the cluster and the main physical properties of its stellar content. Cluster membership is estimated for every individual star by means of zero-age main sequence (ZAMS) and isochrone fitting. The cluster is confirmed to host a rich population of pre-main-sequence (PMS) objects and to contain a large number of X-ray-emitting stars, which reach from the PMS members of GK spectral type up to the most luminous OB main-sequence (MS) members. The PMS cluster members show no significant age spread, and the comparison to both PMS and post-MS isochrones suggests an homogeneous age for all cluster members. The analysis allows us to assess the validity of currently used PMS evolutionary models and supports the suggestion of a well-defined positive correlation of the X-ray emission from PMS stars with their bolometric luminosity. Clear differences are found between the X-ray activity properties of MS and PMS cluster members, both in the relation between X-ray luminosity and bolometric luminosity, and in spectral properties as well.
2249. Multiwavelength catalog in the SEP field
ID:
ivo://CDS.VizieR/J/ApJS/223/1
Title:
Multiwavelength catalog in the SEP field
Short Name:
J/ApJS/223/1
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the Spitzer-IRAC/MIPS Extragalactic survey (SIMES) in the South Ecliptic Pole field. The large area covered (7.7deg^2^), together with one of the lowest Galactic cirrus emissions in the entire sky and a very extensive coverage by Spitzer, Herschel, Akari, and GALEX, make the SIMES field ideal for extragalactic studies. The elongated geometry of the SIMES area (~4:1), allowing for significant cosmic variance reduction, further improves the quality of statistical studies in this field. Here we present the reduction and photometric measurements of the Spitzer/IRAC data. The survey reaches depths of 1.93 and 1.75{mu}Jy (1{sigma}) at 3.6 and 4.5{mu}m, respectively. We discuss the multiwavelength IRAC-based catalog, completed with optical, mid-, and far-IR observations. We detect 341000 sources with F_3.6um_>=3{sigma}. Of these, 10% have an associated 24{mu}m counterpart, while 2.7% have an associated SPIRE source. We release the catalog through the NASA/IPAC Infrared Science Archive. Two scientific applications of these IRAC data are presented in this paper. First, we compute integral number counts at 3.6{mu}m. Second, we use the [3.6]-[4.5] color index to identify galaxy clusters at z>1.3. We select 27 clusters in the full area, a result consistent with previous studies at similar depth.
2250. Multiwavelength catalog in the SEP field. II.
ID:
ivo://CDS.VizieR/J/ApJ/857/64
Title:
Multiwavelength catalog in the SEP field. II.
Short Name:
J/ApJ/857/64
Date:
21 Oct 2021
Publisher:
CDS
Description:
For a sample of star-forming galaxies in the redshift interval 0.15<z<0.3, we study how both the relative strength of the active galactic nucleus (AGN) infrared emission, compared to that due to the star formation (SF), and the numerical fraction of AGNs change as a function of the total stellar mass of the hosting galaxy group (M_group_^*^) between 10^10.25^ and 10^11.9^M_{sun}_. Using a multicomponent spectral energy distribution SED fitting analysis, we separate the contribution of stars, AGN torus, and star formation to the total emission at different wavelengths. This technique is applied to a new multiwavelength data set in the SIMES field (23 not-redundant photometric bands), spanning the wavelength range from the UV (GALEX) to the far-IR (Herschel) and including crucial AKARI and WISE mid-IR observations (4.5{mu}m<{lambda}<24{mu}m), where the black hole thermal emission is stronger. This new photometric catalog, which includes our best photo-z estimates, is released through the NASA/IPAC Infrared Science Archive (IRSA). Groups are identified through a friends-of-friends algorithm (~62% purity, ~51% completeness). We identified a total of 45 galaxies requiring an AGN emission component, 35 of which are in groups and 10 in the field. We find the black hole accretion rate (BHAR){prop.to}(M_group_^*^)^1.21+/-0.27^ and (BHAR/SFR) {\prop} (M_group_^*^)^1.04+/- 0.24^, while, in the same range of M_group_^*^, we do not observe any sensible change in the numerical fraction of AGNs. Our results indicate that the nuclear activity (i.e., the BHAR and the BHAR/SFR ratio) is enhanced when galaxies are located in more massive and richer groups.