- ID:
- ivo://CDS.VizieR/J/AJ/155/48
- Title:
- California-Kepler Survey (CKS). V. Masses and radii
- Short Name:
- J/AJ/155/48
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have established precise planet radii, semimajor axes, incident stellar fluxes, and stellar masses for 909 planets in 355 multi-planet systems discovered by Kepler. In this sample, we find that planets within a single multi-planet system have correlated sizes: each planet is more likely to be the size of its neighbor than a size drawn at random from the distribution of observed planet sizes. In systems with three or more planets, the planets tend to have a regular spacing: the orbital period ratios of adjacent pairs of planets are correlated. Furthermore, the orbital period ratios are smaller in systems with smaller planets, suggesting that the patterns in planet sizes and spacing are linked through formation and/or subsequent orbital dynamics. Yet, we find that essentially no planets have orbital period ratios smaller than 1.2, regardless of planet size. Using empirical mass-radius relationships, we estimate the mutual Hill separations of planet pairs. We find that 93% of the planet pairs are at least 10 mutual Hill radii apart, and that a spacing of ~20 mutual Hill radii is most common. We also find that when comparing planet sizes, the outer planet is larger in 65%+/-0.4% of cases, and the typical ratio of the outer to inner planet size is positively correlated with the temperature difference between the planets. This could be the result of photo-evaporation.
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- ID:
- ivo://CDS.VizieR/J/AJ/156/264
- Title:
- California-Kepler Survey. VII. Planet radius gap
- Short Name:
- J/AJ/156/264
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The distribution of planet sizes encodes details of planet formation and evolution. We present the most precise planet size distribution to date based on Gaia parallaxes, Kepler photometry, and spectroscopic temperatures from the California-Kepler Survey. Previously, we measured stellar radii to 11% precision using high-resolution spectroscopy; by adding Gaia astrometry, the errors are now 3%. Planet radius measurements are, in turn, improved to 5% precision. With a catalog of ~1000 planets with precise properties, we probed in fine detail the gap in the planet size distribution that separates two classes of small planets, rocky super-Earths and gas-dominated sub-Neptunes. Our previous study and others suggested that the gap may be observationally under-resolved and inherently flat-bottomed, with a band of forbidden planet sizes. Analysis based on our new catalog refutes this; the gap is partially filled in. Two other important factors that sculpt the distribution are a planet's orbital distance and its host-star mass, both of which are related to a planet's X-ray/UV irradiation history. For lower-mass stars, the bimodal planet distribution shifts to smaller sizes, consistent with smaller stars producing smaller planet cores. Details of the size distribution including the extent of the "sub-Neptune desert" and the width and slope of the gap support the view that photoevaporation of low-density atmospheres is the dominant evolutionary determinant of the planet size distribution.
- ID:
- ivo://CDS.VizieR/J/AJ/156/254
- Title:
- California-Kepler Survey.VI. Kepler multis & singles
- Short Name:
- J/AJ/156/254
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The California-Kepler Survey (CKS) catalog contains precise stellar and planetary properties for the Kepler planet candidates, including systems with multiple detected transiting planets ("multis") and systems with just one detected transiting planet ("singles", although additional planets could exist). We compared the stellar and planetary properties of the multis and singles in a homogeneous subset of the full CKS-Gaia catalog. We found that sub-Neptune-sized singles and multis do not differ in their stellar properties or planet radii. In particular: (1) The distributions of stellar properties M_*_, [Fe/H], and vsini for the Kepler sub-Neptune-sized singles and multis are statistically indistinguishable. (2) The radius distributions of the sub-Neptune-sized singles and multis with P>3 days are indistinguishable, and both have a valley at ~1.8 R_{Earth}_. However, there are significantly more detected short-period (P<3 days), sub-Neptune-sized singles than multis. The similarity of the host-star properties, planet radii, and radius valley for singles and multis suggests a common origin. The similar radius valley, which is likely sculpted by photo-evaporation from the host star within the first 100 Myr, suggests that planets in both singles and multis spend much of the first 100 Myr near their present, close-in locations. One explanation that is consistent with the similar fundamental properties of singles and multis is that many of the singles are members of multi-planet systems that underwent planet-planet scattering.
- ID:
- ivo://CDS.VizieR/J/A+A/642/A76
- Title:
- California molecular cloud CO datacubes
- Short Name:
- J/A+A/642/A76
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Dense molecular filaments are central to the star formation process, but the detailed manner in which they fragment into prestellar cores is not well understood yet. Here, we investigate the fragmentation properties and dynamical state of several star-forming filaments in the X-shaped nebula region of the California molecular cloud in an effort to shed some light on this issue. We used multiwavelength far-infrared images from Herschel as well as the getsources and getfilaments extraction methods to identify dense cores and filaments in the region and derive their basic properties. We also used a map of ^13^CO(2-1) emission from the Arizona 10m Submillimeter Telescope (SMT) to constrain the dynamical state of the filaments. We identified ten filaments with aspect ratios of AR>4 and column density contrasts of C>0.5, as well as 57 dense cores, including two protostellar cores, 20 robust prestellar cores, 11 candidate prestellar cores, and 24 unbound starless cores. All ten filaments have roughly the same deconvolved full width at half maximum (FWHM), with a median value of 0.12+/-0.03pc, which is independent of their column densities ranging from <10^21^cm^-2^ to >10^22^cm^-2^. Two star-forming filaments (# 8 and # 10) stand out since they harbor quasi-periodic chains of dense cores with a typical projected core spacing of ~0.15pc. These two filaments have thermally supercritical line masses and are not static. Filament 8 exhibits a prominent transverse velocity gradient, suggesting that it is accreting gas from the parent cloud gas reservoir at an estimated rate of ~40+/-10M_{sun}_/Myr/pc. Filament 10 includes two embedded protostars with outflows and it is likely at a somewhat later evolutionary stage than filament 8. In both cases, the observed (projected) core spacing is similar to the filament width and significantly shorter than the canonical separation of ~4 times the filament width predicted by classical cylinder fragmentation theory. It is unlikely that projection effects can explain this discrepancy. We suggest that the continuous accretion of gas onto the two star-forming filaments, as well as the geometrical bending of the filaments, may account for the observed core spacing. Our findings suggest that the characteristic fragmentation lengthscale of molecular filaments is quite sensitive to external perturbations from the parent cloud, such as the gravitational accretion of ambient material.
- ID:
- ivo://CDS.VizieR/J/AJ/157/229
- Title:
- CALSPEC: WFC3 infrared grism spectrophotometry
- Short Name:
- J/AJ/157/229
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The collections of spectral energy distributions (SEDs) in the Hubble Space Telescope (HST) CALSPEC database are augmented by 19 infrared (IR) SEDs from Wide Field Camera 3 (WFC3) IR grism spectra. Together, the two IR grisms, G102 and G141, cover the 0.8-1.7 {mu}m range with resolutions of R=200 and 150, respectively. These new WFC3 SEDs overlap existing CALSPEC Space Telescope Imaging Spectrograph (STIS) standard star flux distributions at 0.8-1 {mu}m with agreement to ~<1%. Some CALSPEC standards already have near-IR camera and multi-object spectrogragh (NICMOS) SEDs; but in their overlap region at 0.8-1.7 {mu}m, the WFC3 data have better wavelength accuracy, better spectral resolution, better repeatability, and, consequently, better flux distributions of ~1% accuracy in our CALSPEC absolute flux SEDs versus ~2% for NICMOS. With the improved SEDs in the WFC3 range, the modeled extrapolations to 32 {mu}m for the James Webb Space Telescope flux standards begin to lose precision longward of the 1.7 {mu}m WFC3 limit, instead of at the 1.0-{mu}m-long wavelength limit for STIS. For example, the extrapolated IR flux longward of 1.7 {mu}m for 1808347 increases by ~1% for the model fit to the data with WFC3, instead of just to the STIS SED alone.
- ID:
- ivo://CDS.VizieR/J/AJ/120/2190
- Title:
- Caltech Faint Galaxy Redshift Survey. XIV
- Short Name:
- J/AJ/120/2190
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Morphological classifications are reported for Hubble Space Telescope images of 241 galaxies in the Hubble Deep Field and its flanking fields with measured redshifts in the interval 0.25<z<1.2, drawn from a magnitude-limited redshift survey to R=24.0. The galaxies are divided into three groups with redshifts in the intervals 0.25-0.6, 0.6-0.8, and 0.8-1.2. R_606_ images from the first group and I814 images from the second and third groups are compared with B-band images of nearby galaxies. All classifications were therefore made at approximately the same rest wavelength. Selection biases are discussed.
- ID:
- ivo://CDS.VizieR/J/AJ/122/611
- Title:
- Caltech Faint Galaxy Redshift Survey. XV.
- Short Name:
- J/AJ/122/611
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- To circumvent the spatial effects of resolution on galaxy classification, the images of 233 objects of known redshift in the Hubble Deep Field (HDF) and its flanking fields that have redshifts in the range 0.20<z<1.10 were degraded to the resolution that they would have had if they were all located at a redshift of z=1.00. As in Paper XIV (Cat. <J/AJ/120/2190>) of the present series, the effects of shifts in rest wavelength were mitigated by using R-band images for the classification of galaxies with 0.2<z<0.6 and I-band images for objects with redshifts 0.6<z<1.1. A special effort was made to search for bars in distant galaxies. The present data strongly confirm the previous conclusion that the Hubble tuning fork diagram only provides a satisfactory framework for the classification of galaxies with z<0.3. More distant disk galaxies are often difficult to shoehorn into the Hubble classification scheme. The paucity of barred spirals and grand-design spirals at large redshifts is confirmed. It is concluded that the morphology of disk galaxies observed at look-back times smaller than 3-4Gyr differs systematically from that of more distant galaxies viewed at look-back times of 4-8Gyr. The disks of late-type spirals at z>0.5 are seen to be more chaotic than those of their nearer counterparts. Furthermore, the spiral structure in distant early-type spirals appears to be less well developed than it is in nearby early galaxies.
2528. CALYMHA survey. I.
- ID:
- ivo://CDS.VizieR/J/MNRAS/466/1242
- Title:
- CALYMHA survey. I.
- Short Name:
- J/MNRAS/466/1242
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the CAlibrating LYMan-{alpha} with H{alpha} (CALYMHA) pilot survey and new results on Lyman {alpha} (Ly{alpha}) selected galaxies at z~2. We use a custom-built Ly{alpha} narrow-band filter at the Isaac Newton Telescope, designed to provide a matched volume coverage to the z=2.23H{alpha} HiZELS survey. Here, we present the first results for the COSMOS and UDS fields. Our survey currently reaches a 3{sigma} line flux limit of ~4x10^-17^erg/s/cm^2^, and a Ly{alpha} luminosity limit of ~10^42.3^erg/s. We find 188 Ly{alpha} emitters over 7.3x10^5^Mpc^3^, but also find significant numbers of other line-emitting sources corresponding to HeII, CIII] and CIV emission lines. These sources are important contaminants, and we carefully remove them, unlike most previous studies. We find that the Ly{alpha} luminosity function at z=2.23 is very well described by a Schechter function up to L_Ly{alpha}_~=10^43^erg/s^ with L*=10^42.59(10^42.75^-10^42.01^)erg/s, {phi}*=10^-3.09^(10^-3.43^-10^2.95)Mpc^-3^ and {alpha}=-1.75+/-0.25. Above L_Ly{alpha}_~=10^43^erg/s, the Ly{alpha} luminosity function becomes power-law like, driven by X-ray AGN. We find that Ly{alpha}-selected emitters have a high escape fraction of 37+/-7 per cent, anticorrelated with Ly{alpha} luminosity and correlated with Ly{alpha} equivalent width. Ly{alpha} emitters have ubiquitous large (~=40kpc) Ly{alpha} haloes, ~2 times larger than their H{alpha} extents. By directly comparing our Ly{alpha} and H{alpha} luminosity functions, we find that the global/overall escape fraction of Ly{alpha} photons (within a 13kpc radius) from the full population of star-forming galaxies is 5.1+/-0.2 per cent at the peak of the star formation history. An extra 3.3+/-0.3 per cent of Ly{alpha} photons likely still escape, but at larger radii.
- ID:
- ivo://CDS.VizieR/J/BaltA/16/327
- Title:
- Camelopardalis dust and molecular clouds
- Short Name:
- J/BaltA/16/327
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using infrared photometric data extracted from the 2MASS, IRAS and MSX databases, 142 suspected young stellar objects (YSOs) are selected from about 2 million stars in the Camelopardalis segment of the Milky Way limited by Galactic coordinates, b=132-158{deg},+/-12{deg}.
- ID:
- ivo://nasa.heasarc/cgpsngpcat
- Title:
- Canadian Galactic Plane Survey (CGPS) 1420-MHz Compact Source Catalog
- Short Name:
- CGPSNGPCAT
- Date:
- 09 May 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains a catalog of compact sources of radio emission at 1420 MHz in the northern Galactic plane from the Canadian Galactic Plane Survey (CGPS). The catalog contains 72,758 compact sources with an angular size less than 3 arcminutes within the Galactic longitude range 52 < l<sub>II</sub> < 192 degrees down to a 5-sigma detection level of ~1.2 mJy. Linear polarization properties are included for 12,368 sources with signals greater than 4 x sigma<sub>QU</sub> in the CGPS Stokes Q and U images at the position of the total intensity peak. In the reference paper, the authors compare the CGPS flux densities with the catalogued flux densities in the Northern VLA Sky Survey (NVSS) catalog for 10,897 isolated unresolved sources with CGPS flux density greater than 4 mJy in order to search for sources that show variable flux density on timescales of several years. They identify 146 candidate variables that exhibit high fractional variations between the two surveys. In addition, they identify 13 candidate transient sources that have CGPS flux density above 10 mJy but that are not detected in the NVSS. In the CGPS, the Synthesis Telescope at the Dominion Radio Astrophysical Observatory (the DRAO ST) provided arcminute-resolution images of the radio continuum and atomic-hydrogen line emission of the northern Galactic Plane. The CGPS DRAO radio continuum observations provided images of Stokes I, Q, and U in four 7.5-MHz sub-bands spanning 35 MHz, centered on 1420 MHz. The observations were carried out in three phases beginning in 1995 and ending in 2009. The sky coverage of each phase and the observing dates are listed in Table 1 of the reference paper. The Galactic plane was covered with a width in Galactic latitude of 9 degrees, centered at b<sub>II</sub> = 1 degree to accommodate the warp of the Galactic disk. The longitude coverage was constrained by the southern Declination limit of ~20 degrees, the range that could be effectively imaged by a linear east-west synthesis telescope array. The Phase II observations included an extension to higher latitudes (b<sub>II</sub> = 17.5 degrees) over a restricted range of longitude. In this table, we present the CGPS 1420-MHz compact source catalog covering 1,464 square degrees and spanning a range of 140 degrees of Galactic longitude between 52 and 192 degrees. This table was created by the HEASARC in June 2017 based upon a machine-readable version of Table 2 from the reference paper that was obtained from the AJ web site. This is a service provided by NASA HEASARC .