- ID:
- ivo://CDS.VizieR/J/A+A/631/A136
- Title:
- 7 CMa system velocity curves
- Short Name:
- J/A+A/631/A136
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the discovery of a second planet orbiting the K giant star 7 CMa based on 166 high-precision radial velocities obtained with Lick, HARPS, UCLES and SONG. The periodogram analysis reveals two periodic signals of approximately 745 and 980d, associated to planetary companions. A double-Keplerian orbital fit of the data reveals two Jupiter-like planets with minimum masses M_b_sini~1.9Mj and M_c_sini~0.9Mj, orbiting at semi-major axes of a_b_~1.75au and a_c_~2.15au, respectively. Given the small orbital separation and the large minimum masses of the planets close encounters may occur within the time baseline of the observations, thus, a more accurate N-body dynamical modeling of the available data is performed. The dynamical best-fit solution leads to collision of the planets and we explore the long-term stable configuration of the system in a Bayesian framework, confirming that 13% of the posterior samples are stable for at least 10Myr. The result from the stability analysis indicates that the two-planets are trapped in a low-eccentricity 4:3 mean-motion resonance. This is only the third discovered system to be inside a 4:3 resonance, making it very valuable for planet formation and orbital evolution models.
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- ID:
- ivo://CDS.VizieR/J/A+A/591/A50
- Title:
- CMB intensity map from WMAP and Planck PR2 data
- Short Name:
- J/A+A/591/A50
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We describe a new estimate of the cosmic microwave background (CMB) intensity map reconstructed by a joint analysis of the full Planck 2015 data (PR2) and nine years of WMAP data. The proposed map provides more than a mere update of the CMB map introduced in a previous paper since it benefits from an improvement of the component separation method L-GMCA (Local-Generalized Morphological Component Analysis), which facilitates efficient separation of correlated components. Based on the most recent CMB data, we further confirm previous results showing that the proposed CMB map estimate exhibits appealing characteristics for astrophysical and cosmological applications: i) it is a full-sky map as it did not require any inpainting or interpolation postprocessing, ii) foreground contamination is very low even on the galactic center, and iii) the map does not exhibit any detectable trace of thermal SZ contamination. We show that its power spectrum is in good agreement with the Planck PR2 official theoretical best-fit power spectrum. Finally, following the principle of reproducible research, we provide the codes to reproduce the L-GMCA, which makes it the only reproducible CMB map.
- ID:
- ivo://CDS.VizieR/J/A+A/608/A100
- Title:
- CMD and mass distribution of Ba stars
- Short Name:
- J/A+A/608/A100
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- With the availability of parallaxes provided by the Tycho-Gaia Astrometric Solution, it is possible to construct the Hertzsprung-Russell diagram (HRD) of barium and related stars with unprecedented accuracy. A direct result from the derived HRD is that subgiant CH stars occupy the same region as barium dwarfs, contrary to what their designations imply. By comparing the position of barium stars in the HRD with STAREVOL evolutionary tracks, it is possible to evaluate their masses, provided the metallicity is known. We used an average metallicity [Fe/H]=-0.25 and derived the mass distribution of barium giants. The distribution peaks around 2.5M_{sun}_, with a tail at higher masses up to 4.5M_{sun}_. This peak is seen as well in the mass distribution of a sample of normal K and M giants used for comparison and is associated with stars located in the red clump. When we compare these mass distributions, we see a deficit of low-mass (1-2M_{sun}_) barium giants. This is probably because low-mass stars reach large radii at the tip of the red giant branch, which may have resulted in an early binary interaction. Among barium giants, the high-mass tail is however dominated by stars with a barium index (based on a visual inspection of the barium spectral line) less than unity, i.e., with a very moderate barium line strength. We believe that these stars are not genuine barium giants, but rather bright giants (or supergiants) where the barium lines are strengthened because of a positive luminosity effect. Moreover, contrary to previous claims, we do not see differences between the mass distributions of mild and strong barium giants.
- ID:
- ivo://CDS.VizieR/J/ApJS/227/25
- Title:
- 6 & 1.3cm deep VLA obs. toward 58 high-mass SFRs
- Short Name:
- J/ApJS/227/25
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a high-sensitivity radio continuum survey at 6 and 1.3cm using the Karl G. Jansky Very Large Array toward a sample of 58 high-mass star-forming regions. Our sample was chosen from dust clumps within infrared dark clouds with and without IR sources (CMC-IRs and CMCs, respectively), and hot molecular cores (HMCs), with no previous, or relatively weak radio continuum detection at the 1mJy level. Due to the improvement in the continuum sensitivity of the Very Large Array, this survey achieved map rms levels of ~3-10{mu}Jy/beam at sub-arcsecond angular resolution. We extracted 70 continuum sources associated with 1.2mm dust clumps. Most sources are weak, compact, and prime candidates for high-mass protostars. Detection rates of radio sources associated with the millimeter dust clumps for CMCs, CMC-IRs, and HMCs are 6%, 53%, and 100%, respectively. This result is consistent with increasing high-mass star formation activity from CMCs to HMCs. The radio sources located within HMCs and CMC-IRs occur close to the dust clump centers, with a median offset from it of 12000au and 4000au, respectively. We calculated 5-25GHz spectral indices using power-law fits and obtained a median value of 0.5 (i.e., flux increasing with frequency), suggestive of thermal emission from ionized jets. In this paper we describe the sample, observations, and detections.
3865. CMD for And III
- ID:
- ivo://CDS.VizieR/J/AJ/106/986
- Title:
- CMD for And III
- Short Name:
- J/AJ/106/986
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The prime focus CCD camera of the KPNO 4 m telescope has been used to image Andromeda III, a dwarf spheroidal galaxy companion to M31, in the V and I bands. The resulting color-magnitude diagram shows a well defined giant branch whose tip luminosity corresponds to that expected for an old metal-poor population at the distance of M31. By comparing these data with the giant branches of metal-poor population at the distance of M31. By comparing these data with the giant branches of Galactic globular clusters, we determine that the abundance of And III is [Fe/H]=-2.0+/-0.15; with this abundance And III lies on the luminosity-abundance relation defined by the Galactic dwarf spheroidal galaxies. There is some evidence for a small (0.16<{sigma}([Fe/H])<0.24) intrinsic abundance dispersion within And III, but we are unable to unambiguously establish its presence. A study of the And III I-band luminosity function yields a distance modulus (m-M)_0_ of 24.4+/-0.2 for this galaxy, and indicates that the fraction of intermediate-age (3 to 10Gyr) population in And III is approximately 10+/-10 percent. In all these aspects And III, like And I, is similar to the Galactic dwarf spheroidal systems, indicating that M31 and the Galaxy provided similar conditions for the evolution of such galaxies.
- ID:
- ivo://nasa.heasarc/ld7c151mhz
- Title:
- 7C 151-MHz Low-Declination Survey Catalog
- Short Name:
- LD7C151MHZ
- Date:
- 27 Sep 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Cambridge Low Frequency Synthesis Telescope (CLFST) has been used at 151 MHz to survey a region of 1393 square degrees, in the range of RA from 9<sup>h</sup> to 16<sup>h</sup>, and of Dec from 20<sup>o</sup> to 35<sup>o</sup>, with an angular resolution of 108 x 108cosec(Dec) arcsec<sup>2</sup>. The rms noise in the maps is in general ~ 35 - 55 mJy/beam, but varies considerably and exceeds this in some areas. The authors have extracted sources with signal-to-noise ratio > 5.5, a total of 5526 sources, and this table contains the catalog of their positions and flux densities. This table was created by the HEASARC in October 2010 based on CDS table J/MNRAS/282/779 file 7c_low.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://CDS.VizieR/J/MNRAS/282/779
- Title:
- 7C 151-MHz survey of region 9-16h 20-35deg
- Short Name:
- J/MNRAS/282/779
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Cambridge Low Frequency Synthesis Telescope has been used at 151 MHz to survey a region of 1393 square degrees, in the range RA 9h to 16h, Dec 20deg to 35deg, with an angular resolution of 108x108cosec(dec) arcsec^2^. The rms noise on the maps is in general ~35-55 mJy/beam but varies considerably and exceeds this in some areas. We have extracted sources with signal-to-noise ratio > 5.5, a total of 5526, and present a catalogue of their positions and flux densities.
- ID:
- ivo://CDS.VizieR/J/MNRAS/298/637
- Title:
- 7C: 151MHz survey of 3 regions
- Short Name:
- J/MNRAS/298/637
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Cambridge Low Frequency Synthesis Telescope has been used at 151MHz to survey three regions centred at RA=10h05min, DE=53{deg}54', RA=10h42min, DE=57{deg}36' and RA=13h32min, DE=38{deg}10', each of area 7.3x7.3cosec(DE)deg^2^. The resolution is 70x70cosec(DE)arcsec^2^, and the rms noise on the maps is typically 15mJy/beam. We present positions and flux densities for 2381 sources which have signal-to-noise ratios >5.5.
- ID:
- ivo://CDS.VizieR/J/A+A/581/A48
- Title:
- 1.3cm line survey toward Orion KL
- Short Name:
- J/A+A/581/A48
- Date:
- 18 Nov 2021 11:23:37
- Publisher:
- CDS
- Description:
- Orion KL has served as a benchmark for spectral line searches throughout the (sub)millimeter regime. The main goal is to systematically study spectral characteristics of Orion KL in the 1.3cm band. We carried out a spectral line survey (17.9GHz to 26.2GHz) with the Effelsberg-100m telescope towards Orion KL. We find 261 spectral lines, yielding an average line density of about 32 spectral features per GHz above 3 sigma. The identified lines include 164 radio recombination lines (RRLs) and 97 molecular lines. A total of 23 molecular transitions from species known to exist in Orion KL are detected for the first time in the interstellar medium. Non-metastable ^15^NH_3_ transitions are detected in Orion KL for the first time. Based on the velocity information of detected lines and the ALMA images, the spatial origins of molecular emission are constrained and discussed. A narrow feature is found in SO_2_ (8_1,7_-7_2,6_), possibly suggesting the presence of a maser line. Column densities and fractional abundances relative to H_2_ are estimated for 12 molecules with LTE methods. Rotational diagrams of non-metastable ^14^NH_3_ transitions with J=K+1 to J=K+4 yield different results; metastable ^15^NH_3_ is found to have a higher excitation temperature than non-metastable ^15^NH_3_, indicating that they may trace different regions. Elemental and isotopic abundance ratios are estimated: ^12^C/^13^C=63+/-17, ^14^N/^15^N=100+/-51, D/H=0.0083+/-0.0045. The dispersion of the He/H ratios derived from H_alpha/He_alpha_ pairs to H_delta_/He_delta_ pairs is very small, which is consistent with theoretical predictions that the departure coefficients bn factors for hydrogen and helium are nearly identical. Based on a non-LTE code neglecting excitation by the infrared radiation field and a likelihood analysis, we find that the denser regions have lower kinetic temperature, which favors an external heating of the Hot Core.
- ID:
- ivo://CDS.VizieR/J/AJ/136/1889
- Title:
- 20cm observations of deep Swire Field
- Short Name:
- J/AJ/136/1889
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results from deep radio observations taken with the Very Large Array at a center frequency of 1400MHz covering a region of the Spitzer Wide-area InfraRed Extragalactic Survey of the Spitzer Legacy survey, centered at 10:46:00, +59:01:00 (J2000). The reduction and cataloging of radio sources are described. An electronic catalog of the sources detected above 5{sigma} is also presented. The survey presented is the deepest so far in terms of the radio source density on the sky. Perhaps surprisingly, the sources down to the bottom of the catalog appear to have median angular sizes still greater than 1-arcsec, like their cousins 10-100 times stronger. The shape of the differential logN-logS counts also seems to require a correction for the finite sizes of the sources to be self-consistent. If the logN-logS normalization remains constant at the lowest flux densities, there are about six sources per square arcminute at 15uJy at 20cm. Given the finite-source size this implies that we may reach the natural confusion limit near 1uJy.