- ID:
- ivo://CDS.VizieR/J/ApJ/709/L114
- Title:
- Protoplanetary disks in PMS binaries
- Short Name:
- J/ApJ/709/L114
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this Letter, I examine several observational trends regarding protoplanetary disks, debris disks, and exoplanets in binary systems in an attempt to constrain the physical mechanisms of planet formation in such a context. Binaries wider than about 100AU are indistinguishable from single stars in all aspects. Binaries in the 5-100AU range, on the other hand, are associated with shorter lived but (at least in some cases) equally massive disks. Furthermore, they form planetesimals and mature planetary systems at a similar rate as wider binaries and single stars, albeit with the peculiarity that they predominantly produce high-mass planets. I posit that the location of a stellar companion influences the relative importance of the core accretion and disk fragmentation planet formation processes, with the latter mechanism being predominant in binaries tighter than 100AU.
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Search Results
- ID:
- ivo://CDS.VizieR/J/ApJ/692/973
- Title:
- Protostars in Perseus, Serpens and Ophiuchus
- Short Name:
- J/ApJ/692/973
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an unbiased census of deeply embedded protostars in Perseus, Serpens, and Ophiuchus, assembled by combining large-scale 1.1mm Bolocam continuum and Spitzer Legacy surveys. We identify protostellar candidates based on their mid-infrared (mid-IR) properties, correlate their positions with 1.1mm core positions from Enoch et al. in 2006 (Cat. J/ApJ/638/293) and 2007ApJ...666..982E, and Young et al. in 2006ApJ...644..326Y, and construct well-sampled spectral energy distributions using our extensive wavelength coverage ({lambda}=1.25-1100um). Source classification based on the bolometric temperature yields a total of 39 Class 0 and 89 Class I sources in the three-cloud sample. We compare to protostellar evolutionary models using the bolometric temperature-luminosity diagram, finding a population of low-luminosity Class I sources that are inconsistent with constant or monotonically decreasing mass accretion rates.
- ID:
- ivo://CDS.VizieR/J/A+A/647/A106
- Title:
- PSZSPT, joint Planck and SPT-SZ cluster catalog
- Short Name:
- J/A+A/647/A106
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first cluster catalogue extracted from combined space- (Planck) and ground-based (South Pole Telescope; SPT-SZ) millimeter data. We develop and apply a Matched Multi-Filter (MMF) capable of dealing with the different transfer functions and resolutions of the two datasets. We verified that it produces results consistent with publications from Planck and SPT collaborations when applied on the datasets individually. We also verified that Planck and SPT-SZ cluster fluxes are consistent with each other. When applied blindly to the combined dataset, the MMF generated a catalogue of 419 detections (S/N>5), of which 323 are already part of the SPT-SZ or PSZ2 catalogues; 54 are new SZ detections, identified in other catalogues or surveys; and 42 are new unidentified candidates. The MMF takes advantage of the complementarity of the two datasets, Planck being particularly useful for detecting clusters at low redshift (z<0.3) while SPT is efficient at finding higher redshift (z>0.3) sources. This work represents a proof of concept that blind cluster extraction can be performed on combined, inhomogeneous millimeter datasets acquired from space and ground. This result is of prime importance for planned ground-based cosmic microwave background (CMB) experiments (e.g., Simons Observatory, CMB-S4) and envisaged CMB space missions (e.g., PICO, Backlight) that will detect hundreds of thousands of clusters in the low mass regime (M500<10^14^M_{sun}_), for which the various sources of intra-cluster emission (gas, dust, synchrotron) will be of same order of magnitude and hence require broad ground+space frequency coverage with comparable spatial resolution for adequate separation.
- ID:
- ivo://CDS.VizieR/J/ApJ/703/285
- Title:
- Radio and IR counterparts of BLAST sources in CDFS
- Short Name:
- J/ApJ/703/285
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have identified radio and/or mid-infrared counterparts to 198 out of 350 sources detected at >=5{sigma} over ~9deg^2^ centered on the Chandra Deep Field South by the Balloon-borne Large Aperture Submillimeter Telescope (BLAST) at 250, 350, and 500um. We have matched 114 of these counterparts to optical sources with previously derived photometric redshifts and fitted spectral energy distributions to the BLAST fluxes and fluxes at 70 and 160um acquired with the Spitzer Space Telescope. In this way, we have constrained dust temperatures, total far-infrared/submillimeter luminosities, and star formation rates for each source. Our findings show that, on average, the BLAST sources lie at significantly lower redshifts and have significantly lower rest-frame dust temperatures compared to submillimeter sources detected in surveys conducted at 850um. We demonstrate that an apparent increase in dust temperature with redshift in our sample arises as a result of selection effects. Finally, we provide the full multiwavelength catalog of >=5{sigma} BLAST sources contained within the complete ~9deg^2^ survey area.
- ID:
- ivo://CDS.VizieR/J/MNRAS/413/2314
- Title:
- Radio and mid-IR counterpart of submm galaxies
- Short Name:
- J/MNRAS/413/2314
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present radio and infrared (3.6-24um) counterparts to submillimetre galaxies (SMGs) detected in the Extended Chandra Deep Field-South with the Large APEX Bolometer Camera (LABOCA) 870um bolometer camera on the 12m Atacama Pathfinder Experiment. Using the Very Large Array at .4GHz and Spitzer, we have identified secure counterparts to 79 of the 126 SMGs [signal-to-noise ratio (S/N)>3.7, S870>4.4mJy] in the field, 62 via their radio and/or 24um emission, the remainder using a colour-flux cut on Infrared Array Camera 3.6um and 5.8um sources chosen to maximize the number of secure, coincident radio and 24um counterparts.
- ID:
- ivo://CDS.VizieR/J/ApJ/886/48
- Title:
- Radio & opt/NIR counterparts of S2COSMOS submm galaxies
- Short Name:
- J/ApJ/886/48
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We identify multi-wavelength counterparts to 1147 submillimeter sources from the S2COSMOS SCUBA-2 survey of the COSMOS field by employing a recently developed radio+machine-learning method trained on a large sample of Atacama Large Millimeter/submillimeter Array (ALMA)-identified submillimeter galaxies (SMGs), including 260 SMGs identified in the AS2COSMOS pilot survey. In total, we identify 1222 optical/near-infrared (NIR)/radio counterparts to the 897 S2COSMOS submillimeter sources with S_850_>1.6mJy, yielding an overall identification rate of (78+/-9)%. We find that (22+/-5)% of S2COSMOS sources have multiple identified counterparts. We estimate that roughly 27% of these multiple counterparts within the same SCUBA-2 error circles very likely arise from physically associated galaxies rather than line-of-sight projections by chance. The photometric redshift of our radio+machine-learning-identified SMGs ranges from z=0.2 to 5.7 and peaks at z=2.3+/-0.1. The AGN fraction of our sample is (19+/-4)%, which is consistent with that of ALMA SMGs in the literature. Comparing with radio/NIR-detected field galaxy population in the COSMOS field, our radio+machine-learning-identified counterparts of SMGs have the highest star formation rates and stellar masses. These characteristics suggest that our identified counterparts of S2COSMOS sources are a representative sample of SMGs at z<~3. We employ our machine-learning technique to the whole COSMOS field and identified 6877 potential SMGs, most of which are expected to have submillimeter emission fainter than the confusion limit of our S2COSMOS surveys (S_850um_<~1.5mJy). We study the clustering properties of SMGs based on this statistically large sample, finding that they reside in high-mass dark matter halos ((1.2+/-0.3)x10^13^h^-1^M_{sun}_), which suggests that SMGs may be the progenitors of massive ellipticals we see in the local universe.
- ID:
- ivo://CDS.VizieR/J/A+A/616/L10
- Title:
- RCW120 fragmentation at 0.01pc scale
- Short Name:
- J/A+A/616/L10
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Little is known about how high-mass stars form. Around 30% of the young high-mass stars in the Galaxy are observed at the edges of ionized (HII) regions. Therefore these are places of choice to study the earliest stages of high-mass star formation, especially towards the most massive condensations. High-spatial resolution observations in the millimeter range might reveal how these stars form and how they assemble their mass. We want to study the fragmentation process down to the 0.01pc scale in the most massive condensation (1700M_{sun}_) observed at the south-western edge of the HII region RCW 120 where the most massive Herschel cores (~124M_{sun}_ in average) could form high-mass stars. Using ALMA 3mm continuum observations towards the densest and most massive millimetric condensation (Condensation 1) of RCW 120, we used the getimages and getsources algorithms to extract the sources detected with ALMA and obtained their physical parameters. The fragmentation of the Herschel cores is discussed through their Jeans mass to understand the properties of the future stars. We extracted 18 fragments from the ALMA continuum observation at 3mm towards 8 cores detected with Herschel, whose mass and deconvolved size range from 2M_{sun}_ to 32M_{sun}_ and from 1.6mpc to 28.8mpc, respectively. The low degree of fragmentation observed, regarding to the thermal Jeans fragmentation, suggests that the observed fragmentation is inconsistent with ideal gravitational fragmentation and other ingredients such as turbulence or magnetic fields should be added in order to explain it. Finally, the range of fragments' mass indicates that the densest condensation of RCW 120 is a favourable place for the formation of high-mass stars with the presence of a probable UCHII region associated with the 27M_{sun}_ Fragment 1 of Core 2.
- ID:
- ivo://CDS.VizieR/J/A+A/525/A149
- Title:
- Red MSX Survey (RMS): bolometric fluxes of YSOs
- Short Name:
- J/A+A/525/A149
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Red MSX Source (RMS) survey is returning a large sample of massive young stellar objects (MYSOs) and ultra-compact (UC) HII regions using follow-up observations of colour-selected candidates from the MSX point source catalogue. To obtain the bolometric fluxes and, using kinematic distance information, the luminosities for young RMS sources with far-infrared fluxes.
- ID:
- ivo://CDS.VizieR/J/MNRAS/478/5579
- Title:
- Refined sample of Lyman excess H II regions
- Short Name:
- J/MNRAS/478/5579
- Date:
- 08 Feb 2022 11:53:49
- Publisher:
- CDS
- Description:
- A large number (67) of the compact/ultra-compact HII regions identified in the Coordinated Radio and Infrared Survey for High-Mass Star Formation catalogue were determined to be powered by a Lyman continuum flux in excess of what was expected given their corresponding luminosity. In this study we attempt to reasonably explain the Lyman excess phenomenon in as many of the 67 HII regions as possible through a variety of observational and astrophysical means including new luminosity estimates, new Herschel photometry, new distance determinations, the use of different models for dust and ionized gas covering factors, and the use of different stellar calibrations. This phenomenon has been observed before; however, the objects shown to exhibit this behaviour in the literature have decidedly different physical properties than the regions in our sample, and thus the origin of the excess is not the same. We find that the excess can be reproduced using OB stellar atmosphere models that have been slightly modified in the extreme ultraviolet. Though the exact mechanism producing the excess is still uncertain, we do find that a scaled up magnetospheric accretion model, often used to explain similar emission from T Tauri stars, is unable to match our observations. Our results suggest that the Lyman excess may be associated with younger HII regions, and that it is more commonly found in early B-type stars. Our refined sample of 24 Lyman excess HII regions provides an ideal sample for comparative studies with regular HII regions, and can act as the basis for the further detailed study of individual regions.
360. RMC143 ALMA images
- ID:
- ivo://CDS.VizieR/J/A+A/626/A126
- Title:
- RMC143 ALMA images
- Short Name:
- J/A+A/626/A126
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The luminous blue variable (LBV) RMC143 is located in the outskirts of the 30~Doradus complex, a region rich with interstellar material and hot luminous stars. We report the 3{sigma} sub-millimetre detection of its circumstellar nebula with ALMA. The observed morphology in the sub-millimetre is different than previously observed with HST and ATCA in the optical and centimetre wavelength regimes. The spectral energy distribution (SED) of RMC suggests that two emission mechanisms contribute to the sub-mm emission: optically thin bremsstrahlung and dust. Both the extinction map and the SED are consistent with a dusty massive nebula with a dust mass of 0.055+/-0.018M_{sun}_ (assuming {kappa}_850_=1.7cm^2^/g). To date, RMC143 has the most dusty LBV nebula observed in the Magellanic Clouds. We have also re-examined the LBV classification of RMC143 based on VLT/X-shooter spectra obtained in 2015/16 and a review of the publication record. The radiative transfer code CMFGEN is used to derive its fundamental stellar parameters. We find an effective temperature of ~8500K, luminosity of log(L/L_{sun}_)=5.32, and a relatively high mass-loss rate of 1.0x10^-5^M_{sun}_/yr. The luminosity is much lower than previously thought, which implies that the current stellar mass of ~8M_{sun}_ is comparable to its nebular mass of ~5.5~M_{sun}_ (from an assumed gas-to-dust ratio of 100), suggesting that the star has lost a large fraction of its initial mass in past LBV eruptions or binary interactions. While the star may have been hotter in the past, it is currently not hot enough to ionize its circumstellar nebula. We propose that the nebula is ionized externally by the hot stars in the 30 Doradus star-forming region.
