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4191. Nearby visual double stars UBVRI photometry
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.
4192. Near-Earth asteroid (1917) Cuyo opt. and IR obs.
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.
4193. Near-Earth Object Survey (MANOS) spectroscopy
ID:
ivo://CDS.VizieR/J/AJ/158/196
Title:
Near-Earth Object Survey (MANOS) spectroscopy
Short Name:
J/AJ/158/196
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Mission Accessible Near-Earth Object Survey (MANOS) aims to observe and characterize small (mean absolute magnitude H~25 mag) Near-Earth Objects (NEOs) that are accessible by spacecraft (mean {Delta}~5.7 km/s) and that make close approaches with the Earth (mean Minimum Orbital Intersection Distance MOID ~0.03 au). We present here the first results of the MANOS visible spectroscopic survey. The spectra were obtained from August 2013 to March 2018 at Lowell Observatory's Discovery Channel 4.3 m telescope, and both Gemini North and South facilities. In total, 210 NEOs have been observed and taxonomically classified. Our taxonomic distribution shows significant variations with respect to surveys of larger objects. We suspect these to be due to a dependence of Main Belt source regions on object size. Compared to previous surveys of larger objects, we report a lower fraction of S+Q-complex asteroids of 43.8+/-4.6%. We associate this decrease with a lack of Phocaea family members at very small size. We also report higher fractions of X-complex and A-type asteroids of 23.8+/-3.3% and 3.8+/-1.3% respectively due to an increase of Hungaria family objects at small size. We find a strong correlation between the Q/S ratio and perihelion distance. We suggest this correlation is due to planetary close encounters with Venus playing a major role in turning asteroids from S to Q-type. This hypothesis is supported by a similar correlation between the Q/S ratio and Venus MOID.
4194. Near-Earth Object Survey (MANOS): 4yrs photometry
ID:
ivo://CDS.VizieR/J/ApJS/239/4
Title:
Near-Earth Object Survey (MANOS): 4yrs photometry
Short Name:
J/ApJS/239/4
Date:
21 Oct 2021
Publisher:
CDS
Description:
Over 4.5 years, the Mission Accessible Near-Earth Object Survey assembled 228 near-Earth object (NEO) light curves. We report rotational light curves for 82 NEOs, constraints on amplitudes and periods for 21 NEOs, light curves with no detected variability within the image signal-to-noise and length of our observing block for 30 NEOs, and 10 tumblers. We uncovered two ultra-rapid rotators with periods below 20s,--2016 MA with a potential rotational periodicity of 18.4s, and 2017 QG18 rotating in 11.9s--and estimated the fraction of fast/ultra-rapid rotators undetected in our project plus the percentage of NEOs with a moderate/long periodicity undetectable during our typical observing blocks. We summarize the findings of a simple model of synthetic NEOs to infer the object's morphology distribution using the measured distribution of light curve amplitudes. This model suggests that a uniform distribution of axis ratio can reproduce the observed sample. This suggests that the quantity of spherical NEOs (e.g., Bennu) is almost equivalent to the quantity of highly elongated objects (e.g., Itokawa), a result that can be directly tested thanks to shape models from Doppler delay radar imaging analysis. Finally, we fully characterized two NEOs-2013 YS2 and 2014 FA7-as appropriate targets for a potential robotic/human mission due to their moderate spin periods and low {Delta}v.
4195. Near-infrared emission from the dayside of WASP-5b
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.
4196. Near infrared imaging of cometary globule CG12
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.
4197. Near-infrared imaging polarimetry in S106
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.
4198. Near-infrared imaging polarimetry of GGD 27
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.
4199. Near-infrared Mira period-luminosity relations in M33
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.
4200. Near-infrared observations of 84 KOI systems
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.