- ID:
- ivo://CDS.VizieR/J/ApJS/247/11
- Title:
- RV photon limits of well-characterized F-M stars
- Short Name:
- J/ApJS/247/11
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The determination of extrasolar planet masses with the radial velocity (RV) technique requires spectroscopic Doppler information from the planet's host star, which varies with stellar brightness and temperature. We analyze the Doppler information in spectra from dwarfs of spectral types F-M utilizing empirical information from HARPS and CARMENES data and model spectra. We revisit the question of whether optical or near-infrared instruments are more efficient for RV observations in low-mass stars, and we come to the conclusion that an optical setup (BVR bands) is more efficient than a near-infrared one (YJHK) in dwarf stars hotter than 3200K. We publish a catalog of 46480 well-studied F-M dwarfs in the solar neighborhood, and we compare its distribution to more than 1 million stars from Gaia DR2. For all stars, we estimate the RV photon noise achievable in typical observations under the assumption of no activity jitter and slow rotation. We find that with an ESPRESSO-like instrument at an 8m telescope, a photon noise limit of 10cm/s or lower can be reached in more than 280 stars in a 5 minute observation. At 4m telescopes, a photon noise limit of 1m/s can be reached in a 10 minute exposure in approximately 10000 predominantly Sun-like stars with a HARPS-like (optical) instrument. The same applies to ~3000 stars for a red optical setup that covers the R and I bands and ~700 stars for a near-infrared instrument. For the latter two, many of the targets are nearby M dwarfs. Finally, we identify targets in which Earth-mass planets within the liquid water habitable zone can cause RV amplitudes comparable to the RV photon noise. Assuming the same exposure times as above, we find that an ESPRESSO-like instrument can reach this limit for 1M_{Earth}_ planets in more than 1000 stars. The optical, red optical, and near-infrared configurations reach the limit for 2M_{Earth}_ planets in approximately 500, 700, and 200 stars, respectively. An online tool is provided to estimate the RV photon noise as a function of stellar temperature and brightness and wavelength coverage.
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Search Results
- ID:
- ivo://CDS.VizieR/J/A+A/582/A66
- Title:
- SABOCA NGC 3603 IRS 9A images
- Short Name:
- J/A+A/582/A66
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The formation of massive stars and their arrival on the zero-age main-sequence occurs hidden behind dense clouds of gas and dust. In the giant HII region NGC 3603, the radiation of a young cluster of OB stars has dispersed dust and gas in its vicinity. At a projected distance of 2.5pc from the cluster, a bright mid-infrared (mid-IR) source (IRS 9A) was identified as a massive young stellar object (MYSO), located on the side of a molecular clump (MM2) of gas facing the cluster. We investigated the physical conditions in MM2, based on APEX sub-mm observations using the SABOCA and SHFI instruments, and archival ATCA 3mm continuum and CS spectral line data. We resolved MM2 into several compact cores, one of them closely associated with IRS 9A. These are likely to be infrared dark clouds because they do not show the typical hot-core emission lines and are mostly opaque against the mid-IR background. The compact cores have masses of up to several hundred times the solar mass and gas temperatures of about 50K, without evidence of internal ionizing sources. We speculate that IRS 9A is younger than the cluster stars, but is in an evolutionary state after the compact cores.
- ID:
- ivo://CDS.VizieR/J/ApJS/217/17
- Title:
- SAFIRES: Spitzer Archival FIR Extragalactic Survey
- Short Name:
- J/ApJS/217/17
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the Spitzer Archival Far-InfraRed Extragalactic Survey (SAFIRES). This program produces refined mosaics and source lists for all far-infrared (FIR) extragalactic data taken during the more than six years of the cryogenic operation of the Spitzer Space Telescope. The SAFIRES products consist of FIR data in two wavelength bands (70 and 160{mu}m) across approximately 180 square degrees of sky, with source lists containing far-infrared fluxes for almost 40000 extragalactic point sources. Thus, SAFIRES provides a large, robust archival far-infrared data set suitable for many scientific goals.
- ID:
- ivo://CDS.VizieR/II/305
- Title:
- SAGE LMC and SMC IRAC Source Catalog
- Short Name:
- II/305
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The SAGE project is a Cycle 2 legacy program on the Spitzer Space Telescope, entitled, "Spitzer Survey of the Large Magellanic Cloud: Surveying the Agents of a Galaxy's Evolution (SAGE)", with Margaret Meixner (STScI) as the PI. The project overview and initial results are described in a paper by Meixner et al. (2006AJ....132.2268M). The Catalog is a highly reliable list of 6.4 million sources. Faint limits for SAGE are 18.1, 17.5, 15.3, and 14.2 for IRAC 3.6, 4.5, 5.8, 8.0 um, respectively. The SAGE-SMC project is a Cycle 4 legacy program on the Spitzer Space Telescope, entitled, "SAGE-SMC: Surveying the Agents of Galaxy Evolution in the Tidally-Disrupted, Low-Metallicity Small Magellanic Cloud", with Karl Gordon (STScI) as the PI. The project overview and initial results are described in a paper by Gordon et al. (2011AJ....142..102G). The Catalog is a highly reliable list of 2.0 million sources. Faint limits for SAGE-SMC are 18.3, 17.7, 15.7, and 14.5 for IRAC 3.6, 4.5, 5.8, 8.0 um, respectively. The archive tables are more complete but less reliable than the catalogs. IRAC Single Frame + Mosaic Photometry Catalog: a combination of mosaic photometry source list extracted from the combined Epoch 1 and Epoch 2 12 second frametime mosaics with all-epochs single frame source list, bandmerged with 2MASS or 2MASS6X. Detailed documentations are available from http://irsa.ipac.caltech.edu/data/SPITZER/SAGE/doc/ as SAGEDataProductsDescription_Sep09.pdf and from http://irsa.ipac.caltech.edu/data/SPITZER/SAGE-SMC/docs/ as sage-smc_delivery_apr11.pdf
- ID:
- ivo://CDS.VizieR/J/MNRAS/470/3250
- Title:
- SAGE LMC point-sources classification
- Short Name:
- J/MNRAS/470/3250
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Infrared Spectrograph (IRS) on the Spitzer Space Telescope observed nearly 800 point sources in the Large Magellanic Cloud (LMC), taking over 1000 spectra. 197 of these targets were observed as part of the SAGE-Spec Spitzer Legacy program; the remainder are from a variety of different calibration, guaranteed time and open time projects. We classify these point sources into types according to their infrared spectral features, continuum and spectral energy distribution shape, bolometric luminosity, cluster membership and variability information, using a decision-tree classification method. We then refine the classification using supplementary information from the astrophysical literature. We find that our IRS sample is comprised substantially of YSO and HII regions, post-main-sequence low-mass stars: (post-)asymptotic giant branch stars and planetary nebulae and massive stars including several rare evolutionary types. Two supernova remnants, a nova and several background galaxies were also observed. We use these classifications to improve our understanding of the stellar populations in the LMC, study the composition and characteristics of dust species in a variety of LMC objects, and to verify the photometric classification methods used by mid-IR surveys. We discover that some widely used catalogues of objects contain considerable contamination and others are missing sources in our sample.
- ID:
- ivo://CDS.VizieR/J/ApJ/872/58
- Title:
- Sagittarius stream stars with APOGEE obs.
- Short Name:
- J/ApJ/872/58
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The SDSS-IV Apache Point Observatory Galactic Evolution Experiment (APOGEE) survey provides precise chemical abundances of 18 chemical elements for ~176000 red giant stars distributed over much of the Milky Way Galaxy (MW), and includes observations of the core of the Sagittarius dwarf spheroidal galaxy (Sgr). The APOGEE chemical abundance patterns of Sgr have revealed that it is chemically distinct from the MW in most chemical elements. We employ a k-means clustering algorithm to six-dimensional chemical space defined by [(C+N)/Fe], [O/Fe], [Mg/Fe], [Al/Fe], [Mn/Fe], and [Ni/Fe] to identify 62 MW stars in the APOGEE sample that have Sgr-like chemical abundances. Of the 62 stars, 35 have Gaia kinematics and positions consistent with those predicted by N-body simulations of the Sgr stream, and are likely stars that have been stripped from Sgr during the last two pericenter passages (<2Gyr ago). Another 20 of the 62 stars exhibit chemical abundances indistinguishable from the Sgr stream stars, but are on highly eccentric orbits with median rapo ~25kpc. These stars are likely the "accreted" halo population thought to be the result of a separate merger with the MW 8-11 Gyr ago. We also find one hypervelocity star candidate. We conclude that Sgr was enriched to [Fe/H]~-0.2 before its most recent pericenter passage. If the "accreted halo" population is from one major accretion event, then this progenitor galaxy was enriched to at least [Fe/H]~-0.6, and had a similar star formation history to Sgr before merging.
- ID:
- ivo://CDS.VizieR/J/A+A/635/A54
- Title:
- SBNAF Infrared Database
- Short Name:
- J/A+A/635/A54
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this paper, we present the Small Bodies: Near and Far (SBNAF) Infrared Database, an easy-to-use tool intended to facilitate the modelling of thermal emission of small bodies of the Solar System. Our database collects measurements of thermal emissions for small Solar System targets that are otherwise available in scattered sources and provides a complete description of the data, including all information necessary to perform direct scientific analyses and without the need to access additional external resources. This public database contains representative data of asteroid observations of large surveys (e.g. AKARI, IRAS, and WISE) as well as a collection of small body observations of infrared space telescopes (e.g. the Herschel Space Observatory) and provides a web interface to access this data (https://ird.konkoly.hu).We also provide an example for the direct application of the database and show how it can be used to estimate the thermal inertia of specific populations, e.g. asteroids within a given size range. We show how different scalings of thermal inertia with heliocentric distance (i.e. temperature) may affect our interpretation of the data and discuss why the widely-used radiative conductivity exponent (alpha=-3/4) might not be adequate in general, as suggested in previous studies.
- ID:
- ivo://CDS.VizieR/J/ApJ/820/82
- Title:
- S2CLS: multiwavelength counterparts to SMGs
- Short Name:
- J/ApJ/820/82
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present multiwavelength identifications for the counterparts of 1088 submillimeter sources detected at 850{mu}m in the SCUBA-2 Cosmology Legacy Survey (S2CLS) study of the UKIRT Infrared Deep Sky Survey-Ultra-Deep Survey (UDS) field. By utilizing an Atacama Large Millimeter Array (ALMA) pilot study on a subset of our bright SCUBA-2 sample as a training set, along with the deep optical-near-infrared (OIR) data available in this field, we develop a novel technique, Optical-IR Triple Color (OIRTC), using z-K, K-[3.6], [3.6]-[4.5] colors to select the candidate submillimeter galaxy (SMG) counterparts. By combining radio identification and the OIRTC technique, we find counterpart candidates for 80% of the Class = 1 >=4{sigma} SCUBA-2 sample, defined as those that are covered by both radio and OIR imaging and the base sample for our scientific analyses. Based on the ALMA training set, we expect the accuracy of these identifications to be 82%+/-20%, with a completeness of 69%+/-16%, essentially as accurate as the traditional p-value technique but with higher completeness. We find that the fraction of SCUBA-2 sources having candidate counterparts is lower for fainter 850{mu}m sources, and we argue that for follow-up observations sensitive to SMGs with S_850_>~1mJy across the whole ALMA beam, the fraction with multiple counterparts is likely to be >40% for SCUBA-2 sources at S_850_>~4mJy. We find that the photometric redshift distribution for the SMGs is well fit by a lognormal distribution, with a median redshift of z=2.3+/-0.1. After accounting for the sources without any radio and/or OIRTC counterpart, we estimate the median redshift to be z=2.6+/-0.1 for SMGs with S_850_>1mJy. We also use this new large sample to study the clustering of SMGs and the far-infrared properties of the unidentified submillimeter sources by stacking their Herschel SPIRE far-infrared emission.
- ID:
- ivo://CDS.VizieR/J/MNRAS/379/1571
- Title:
- SCUBA Half-Degree Extragalactic Survey. IV
- Short Name:
- J/MNRAS/379/1571
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the redshift distribution of the Submillimetre Common-User Bolometer Array (SCUBA) Half Degree Survey (SHADES) galaxy population based on the rest-frame radio-mm-far-infrared (FIR) colours of 120 robustly detected 850um sources in the Lockman Hole East (LH) and Subaru XMM-Newton Deep Field (SXDF). The redshift distribution derived from the full spectral energy distribution (SED) information is shown to be narrower than that determined from the radiosub-mm spectral index, as more photometric bands contribute to a higher redshift accuracy.
- ID:
- ivo://CDS.VizieR/J/A+A/561/A83
- Title:
- SDC13 infrared dark clouds spectra
- Short Name:
- J/A+A/561/A83
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Formation of stars is now believed to be tightly linked to the dynamical evolution of interstellar filaments in which they form. In this paper we analyze the density structure and kinematics of a small network of infrared dark filaments, SDC13, observed in both dust continuum and molecular line emission with the IRAM 30m telescope. These observations reveal the presence of 18 compact sources amongst which the two most massive, MM1 and MM2, are located at the intersection point of the parsec-long filaments. The dense gas velocity and velocity dispersion observed along these filaments show smooth, strongly correlated, gradients. We discuss the origin of the SDC13 velocity field in the context of filament longitudinal collapse. We show that the collapse timescale of the SDC13 filaments (from 1Myr to 4Myr depending on the model parameters) is consistent with the presence of Class I sources in them, and argue that, on top of bringing more material to the centre of the system, collapse could generate additional kinematic support against local fragmentation, helping the formation of starless super-Jeans cores. SDC13 is composed of three Spitzer Dark Clouds from the Peretto & Fuller (2009, cat J/A+A/505/405) catalogue (SDC13.174-0.07, SDC13.158-0.073, SDC13.194-0.073).
