- ID:
- ivo://CDS.VizieR/J/AJ/126/2449
- Title:
- Nearby ultracool dwarfs in galactic plane
- Short Name:
- J/AJ/126/2449
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Surveys for nearby low-luminosity dwarfs tend to avoid the crowded regions of the Galactic plane. We have devised near-infrared color-magnitude and color-color selection criteria designed to identify late-type M and early-type L dwarfs within 12pc of the Sun. We use those criteria to search for candidates within the regions of the Galactic plane (|b|<10{deg}) covered by the Second Incremental Data Release from the Two Micron All Sky Survey (<II/241>). Detailed inspection of the available photographic images of the resulting 1299 candidates confirms only two as ultracool dwarfs. Both are known proper-motion stars, identified in the recent survey by Lepine et al. (2003, Cat. <J/AJ/125/1598>). Despite the low numbers, the inferred surface density is consistent with comparable surveys at higher latitudes. We discuss the implications for the luminosity function and consider means of improving the efficiency and scope of photometric surveys in the plane.
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Search Results
- ID:
- ivo://CDS.VizieR/J/A+A/422/1023
- Title:
- Nearby visual double stars UBVRI photometry
- Short Name:
- J/A+A/422/1023
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present accurate CCD astrometric and photometric data for 31 nearby visual double stars in the standard filters BVRI. The observations were collected with a 1.3-m telescope in 2001-2002. The results consist of relative astrometric positions (epoch, angular separation and position angle) and differential BVRI photometry of the components. Mean errors are: 0.01" for the separation; 0.06{deg} for the position angle; and 0.015mag for the photometric data. Comparing the relative positions at different epochs, we evaluate the physical association of the systems. We additionally derive fractional masses and true separations for the most probable binary systems and, whenever orbits are available, also total and component masses.
- ID:
- ivo://CDS.VizieR/J/A+A/627/A172
- Title:
- Near-Earth asteroid (1917) Cuyo opt. and IR obs.
- Short Name:
- J/A+A/627/A172
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The near-Earth asteroid (1917) Cuyo was subject to radar and light curve observations during a close approach in 1989, and observed up until 2008. It was selected as one of our ESO Large Programme targets, aimed at observational detections of the Yarkovsky-O'Keefe-Radzievskii-Paddack (YORP) effect through long-term light curve monitoring and physical modelling of near-Earth asteroids. We aim to constrain the physical properties of Cuyo: shape, spin-state, and spectroscopic & thermophysical properties of the surface. We acquired photometric light curves of Cuyo spanning the period between 2010 and 2013, which we combined with published light curves from 1989-2008. Our thermal-infrared observations were obtained in 2011. Rotationally resolved optical spectroscopy data were acquired in 2011 and combined with all available published spectra to investigate any surface material variegation. We developed a convex light-curve-inversion shape of Cuyo that suggests the presence of an equatorial ridge, typical for an evolved system close to shedding mass due to fast rotation. We determine limits of YORP strength through light-curve-based spin-state modelling, including both negative and positive acceleration values, between -0.7x10^-8^rad/day^2^ and 1.7x10^-8^rad/day^2^. Thermo-physical modelling with the ATPM provides constraints on the geometric albedo, pV=0.24+/-0.07, the effective diameter Deff=3.15+/-0.08km, the thermal inertia =44+/-9J/m^2^/s^1/2^/K, and a roughness fraction of 0.52+/-0.26. This enabled a YORP strength prediction of (-6.39+/-0.96)x10^-10^rad/day^2^. We also see evidence of surface compositional variation. The low value of YORP predicted by means of thermophysical analysis, consistent with the results of the light curve study, might be due to the self-limiting properties of rotational YORP, possibly involving movement of sub-surface and surface material. This may also be consistent with the surface compositional variation that we see. The physical model of Cuyo can be used to investigate cohesive forces as a way to explain why some targets survive rotation rates faster than the fission limit.
- ID:
- ivo://CDS.VizieR/J/A+A/564/A6
- Title:
- Near-infrared emission from the dayside of WASP-5b
- Short Name:
- J/A+A/564/A6
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- WASP-5b is a highly irradiated dense hot Jupiter orbiting a G4V star every 1.6 days. We observed two secondary eclipses of WASP-5b in the J, H and K bands simultaneously. Thermal emission of WASP-5b is detected in the J and K bands. The retrieved planet-to-star flux ratios in the J and K bands are 0.168 +0.050/-0.052% and 0.269+/-0.062%, corresponding to brightness temperatures of 2996 +212/-261K and 2890 +246/-269K, respectively. No thermal emission is detected in the H band, with a 3-sigma upper limit of 0.166%, corresponding to a maximum temperature of 2779K. On the whole, our J, H, K results can be explained by a roughly isothermal temperature profile of ~2700K in the deep layers of the planetary dayside atmosphere that are probed at these wavelengths. Together with Spitzer observations, which probe higher layers that are found to be at ~1900K, a temperature inversion is ruled out in the range of pressures probed by the combined data set. While an oxygen-rich model is unable to explain all the data, a carbon-rich model provides a reasonable fit but violates energy balance.
- ID:
- ivo://CDS.VizieR/J/A+A/510/A1
- Title:
- Near infrared imaging of cometary globule CG12
- Short Name:
- J/A+A/510/A1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Cometary globule 12 is a relatively little investigated medium- and low mass star forming region 210pc above the Galactic plane. This study sets out to discover the possibly embedded members of the CG 12 stellar cluster, to refine the NIR photometry of the known member stars and to study the star formation activity in CG 12 and its relation to the distribution of molecular gas, dust and mid- to far-infrared emission in the cloud. NIR J, H, and Ks imaging and stellar photometry is used to analyse the stellar content and the structure of CG 12.
- ID:
- ivo://CDS.VizieR/J/AJ/137/3149
- Title:
- Near-infrared imaging polarimetry in S106
- Short Name:
- J/AJ/137/3149
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of wide-field JHKS polarimetry toward the HII region S106 using the Infrared Survey Facility telescope. Our polarimetry data revealed an extended (up to ~5') polarized nebula over S106. We confirmed the position of the illuminating source of most of the nebula as consistent with S106 IRS 4 through an analysis of polarization vectors. The bright portion of the polarized intensity is consistent with the red wing component of the molecular gas.
- ID:
- ivo://CDS.VizieR/J/ApJ/824/95
- Title:
- Near-infrared imaging polarimetry of GGD 27
- Short Name:
- J/ApJ/824/95
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Near-infrared imaging polarimetry in the J, H, and K_ s_ bands was carried out for GGD 27 in the dark cloud Lynds 291. Details of an infrared reflection nebula associated with the optical nebulosity GGD27 and the infrared nebula GGD 27 IRS are presented. Aperture photometry of 1263 point-like sources, detected in all three bands, was used to classify them based on a color-color diagram, and the linear polarization of several hundred sources was determined, with the latter used to map the magnetic field structure around GGD 27. This field, around GGD 27 IRS, appears to be associated with the extended CO outflow of IRAS 18162-2048; however, there are partly distorted or bent components in the field. The Chandrasekhar-Fermi method gives an estimate of the magnetic field strength as ~90{mu}G. A region associated with GGD 27 IRS is discovered to have a circular polarization in the range of ~2%-11% in the K_s_ band. The circular polarization has an asymmetric positive/negative pattern and extends out to ~120" or 1.0pc. The circular and linear polarization patterns are explained as resulting from a combination of dense inner and fainter outer lobes, suggesting episodic outflow.
- ID:
- ivo://CDS.VizieR/J/AJ/156/112
- Title:
- Near-infrared Mira period-luminosity relations in M33
- Short Name:
- J/AJ/156/112
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We analyze sparsely sampled near-infrared (JHK_s_) light curves of a sample of 1781 Mira variable candidates in M33, originally discovered using I-band time-series observations. We extend our single-band semi-parametric Gaussian process modeling of Mira light curves to a multiband version and obtain improved period determinations. We use our previous results on near-infrared properties of candidate Miras in the LMC to classify the majority of the M33 sample into oxygen- or carbon-rich subsets. We derive period-luminosity relations for O-rich Miras and determine a distance modulus for M33 of 24.80+/-0.06 mag.
- ID:
- ivo://CDS.VizieR/J/AJ/153/25
- Title:
- Near-infrared observations of 84 KOI systems
- Short Name:
- J/AJ/153/25
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We determine probabilities of physical association for stars in blended Kepler Objects of Interest (KOIs), and find that 14.5%_-3.4%_^+3.8%^ of companions within ~4'' are consistent with being physically unassociated with their primary. This produces a better understanding of potential false positives in the Kepler catalog and will guide models of planet formation in binary systems. Physical association is determined through two methods of calculating multi-band photometric parallax using visible and near-infrared adaptive optics observations of 84 KOI systems with 104 contaminating companions within ~4''. We find no evidence that KOI companions with separations of less than 1'' are more likely to be physically associated than KOI companions generally. We also reinterpret transit depths for 94 planet candidates, and calculate that 2.6%+/-0.4% of transits have R>15R_{oplus}_, which is consistent with prior modeling work.
- ID:
- ivo://CDS.VizieR/J/MNRAS/369/751
- Title:
- Near-infrared photometry of carbon stars
- Short Name:
- J/MNRAS/369/751
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Near-infrared, JHKL, photometry of 239 Galactic C-rich variable stars is presented and discussed. From these and published data, the stars were classified as Mira or non-Mira variables, and amplitudes and pulsation periods, ranging from 222 to 948d for the Miras, were determined for most of them. A comparison of the colour and period relations with those of similar stars in the Large Magellanic Cloud indicates minor differences, which may be the consequence of sample selection effects. Apparent bolometric magnitudes were determined by combining the mean JHKL fluxes with mid-infrared photometry from IRAS and MSX.
