- ID:
- ivo://CDS.VizieR/J/A+A/628/A68
- Title:
- SPHERE image of RY Tau
- Short Name:
- J/A+A/628/A68
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Jets are rarely associated with pre-main-sequence intermediate-mass stars. This contrasts with the frequent detection of jets in lower-mass or younger stars. Optical and near-IR observations of jet-driving sources are often hindered by the presence of a natal envelope. Jets around partly embedded sources are a useful diagnostic to constrain the geometry of the concealed protoplanetary disk. In fact, the jet-driving mechanisms are affected by both spatial anisotropies and episodic variations at the (sub-)au scale from the star. We obtained a rich set of high-contrast VLT/SPHERE observations from 0.6um to 2.2um of the young intermediate-mass star RY Tau. Given the proximity to the Sun of this source, our images have the highest spatial resolution ever obtained for an atomic jet (down to 4au). Optical observations in polarized light show no sign of the protoplanetary disk detected by ALMA. Instead, we observed a diffuse signal resembling a remnant envelope with an outflow cavity. The jet is detected in the H{alpha}, [SII] at 1.03um, HeI at 1.08um, and [FeII] lines in the 1.25um and 1.64um. The jet appears to be wiggling and its radial width increasing with the distance is complementary to the shape of the outflow cavity suggesting a strong jet/envelope interaction. Through the estimated tangential velocity (~100km/s), we revealed a possible connection between the launching time of the jet sub-structures and the stellar activity of RY Tau. RY Tau is at an intermediate stage toward the dispersal of the natal envelope. This source shows episodic increases of mass accretion /ejection similarly to other known intermediate-mass stars. The amount of observed jet wiggle is consistent with the presence of a precessing disk warp or misaligned inner disk that would be induced by an unseen planetary/sub-stellar companion at sub-/few-au scales. The high disk mass of RY Tau and of two other jet-driving intermediate-mass stars, HD163296 and MWC480, suggests that massive, full disks are more efficient at launching prominent jets.
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Search Results
- ID:
- ivo://CDS.VizieR/J/A+A/570/A55
- Title:
- Spiderweb galaxy 870um and 1.4GHz images
- Short Name:
- J/A+A/570/A55
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present APEX LABOCA 870{mu}m observations of the field around the high-redshift radio galaxy MRC1138-262 at z=2.16. We detect 16 submillimeter galaxies (SMGs) in this ~140-arcmin^2^ bolometer map with flux densities in the range 3-11mJy. The raw number counts indicate a density of SMGs that is up to four times that of blank field surveys. Based on an exquisite multiwavelength database, including VLA 1.4 GHz radio and infrared observations, we investigate whether these sources are members of the protocluster structure at z=~2.2. Using Herschel PACS and SPIRE and Spitzer MIPS photometry, we derive reliable far-infrared (FIR) photometric redshifts for all sources. Follow-up VLT ISAAC and SINFONI NIR spectra confirm that four of these SMGs have redshifts of z=~2.2. We also present evidence that another SMG in this field, detected earlier at 850{mu}m, has a counterpart that exhibits H{alpha} and CO(1-0) emission at z=2.15. Including the radio galaxy and two SMGs with FIR photometric redshifts at z=2.2, we conclude that at least eight submm sources are part of the protocluster at z=2.16 associated with the radio galaxy MRC1138-262. We measure a star formation rate density SFRD~1500M_{sun}_/yr/Mpc^3^, four magnitudes higher than the global SFRD of blank fields at this redshift. Strikingly, these eight sources are concentrated within a region of 2Mpc (the typical size of clusters in the local universe) and are distributed within the filaments traced by the HAEs at z=~2.2. This concentration of massive, dusty starbursts is not centered on the submillimeter-bright radio galaxy which could support the infalling of these sources into the cluster center. Approximately half (6/11) of the SMGs that are covered by the H{alpha} imaging data are associated with HAEs, demonstrating the potential of tracing SMG counterparts with this population. To summarize, our results demonstrate that submillimeter observations may enable us to study (proto)clusters of massive, dusty starbursts.
- ID:
- ivo://CDS.VizieR/J/A+A/648/A19
- Title:
- Spiral structure in the gas disc of CQ Tau
- Short Name:
- J/A+A/648/A19
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We used spatially resolved ALMA observations of the three CO isotopologues ^12^CO, ^13^CO and C^18^O (J=2-1) from CQ Tau to analyse the brightness temperature and kinematics of the gas disc. We detect significant spiral structures in both the brightness temperature and the rotation velocity of ^12^CO after subtraction of an azimuthally symmetric model, which may be tracing planet-disc interactions with an embedded planet or low-mass companion. The brightness temperature spirals are morphologically connected to spirals observed in NIR scattered light in the same disc, indicating a common origin. Together with the observed large dust and gas cavity, these spiral structures support the hypothesis of a massive embedded companion in the CQ Tau disc.
- ID:
- ivo://CDS.VizieR/J/MNRAS/417/2239
- Title:
- SPIRE (f250um>17.4mJy) GOODS-N galaxies
- Short Name:
- J/MNRAS/417/2239
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- For the first time, we investigate the X-ray/infrared (IR) correlation for star-forming galaxies (SFGs) at z~1, using SPIRE submm data from the recently launched Herschel Space Observatory and deep X-ray data from the 2-Ms Chandra Deep Field-North survey. We examine the X-ray/IR correlation in the soft X-ray (SX; 0.5-2keV) and hard X-ray (HX; 2-10keV) bands by comparing our z~1 SPIRE-detected SFGs to equivalently IR-luminous (L_IR_>10^10^L_{sun}_) samples in the local/low-redshift Universe.
- ID:
- ivo://CDS.VizieR/J/MNRAS/456/3335
- Title:
- SPIRE observations of Herschel-BAT sample
- Short Name:
- J/MNRAS/456/3335
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present far-infrared (FIR) and submillimetre photometry from the Herschel Space Observatory's Spectral and Photometric Imaging Receiver (SPIRE) for 313 nearby (z<0.05) active galactic nuclei (AGN). We selected AGN from the 58 month Swift Burst Alert Telescope (BAT) catalogue, the result of an all-sky survey in the 14-195keV energy band, allowing for a reduction in AGN selection effects due to obscuration and host galaxy contamination. We find 46 per cent (143/313) of our sample is detected at all three wavebands and combined with our Photoconductor Array Camera and Spectrometer (PACS) observations represents the most complete FIR spectral energy distributions of local, moderate-luminosity AGN. We find no correlation among the 250, 350, and 500{mu}m luminosities with 14-195keV luminosity, indicating the bulk of the FIR emission is not related to the AGN. However, Seyfert 1s do show a very weak correlation with X-ray luminosity compared to Seyfert 2s and we discuss possible explanations. We compare the SPIRE colours (F_250_/F_350_ and F_350_/F_500_) to a sample of normal star-forming galaxies, finding the two samples are statistically similar, especially after matching in stellar mass. But a colour-colour plot reveals a fraction of the Herschel-BAT AGN are displaced from the normal star-forming galaxies due to excess 500{mu}m emission (E_500_). Our analysis shows E_500_ is strongly correlated with the 14-195keV luminosity and 3.4/4.6{mu}m flux ratio, evidence the excess is related to the AGN. We speculate these sources are experiencing millimetre excess emission originating in the corona of the accretion disc.
- ID:
- ivo://CDS.VizieR/J/A+A/575/A79
- Title:
- SPIRE 250um maps of 4 molecular clouds
- Short Name:
- J/A+A/575/A79
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Column-density maps of molecular clouds are one of the most important observables in the context of molecular cloud- and starformation (SF) studies. With the Herschel satellite it is now possible to precisely determine the column density from dust emission, which is the best tracer of the bulk of material in molecular clouds. However, line-of-sight (LOS) contamination from fore- or background clouds can lead to overestimating the dust emission of molecular clouds, in particular for distant clouds. This implies values that are too high for column density and mass, which can potentially lead to an incorrect physical interpretation of the column density probability distribution function (PDF). In this paper, we use observations and simulations to demonstrate how LOS contamination affects the PDF. We apply a first-order approximation (removing a constant level) to the molecular clouds of Auriga and Maddalena (low-mass star-forming), and Carina and NGC3603 (both high-mass SF regions).
- ID:
- ivo://CDS.VizieR/J/ApJ/660/167
- Title:
- Spitzer AGN candidates in CDFN
- Short Name:
- J/ApJ/660/167
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We define a sample of 62 galaxies in the Chandra Deep Field-North whose Spitzer IRAC SEDs exhibit the characteristic power-law emission expected of luminous AGNs. We study the multi-wavelength properties of this sample and compare the AGNs selected in this way to those selected via other Spitzer color-color criteria. Only 55% of the power-law galaxies are detected in the X-ray catalog at exposures of >0.5Ms, although a search for faint emission results in the detection of 85% of the power-law galaxies at the >=2.5sigma detection level. Most of the remaining galaxies are likely to host AGNs that are heavily obscured in the X-ray. Because the power-law selection requires the AGNs to be energetically dominant in the near- and mid-infrared, the power-law galaxies comprise a significant fraction of the Spitzer-detected AGN population at high luminosities and redshifts. The high 24um detection fraction also points to a luminous population. The power-law galaxies comprise a subset of color-selected AGN candidates.
- ID:
- ivo://CDS.VizieR/J/ApJS/244/30
- Title:
- Spitzer catalog of Herschel star-forming galaxies
- Short Name:
- J/ApJS/244/30
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The largest Herschel extragalactic surveys, H-ATLAS and HerMES, have selected a sample of "ultrared" dusty star-forming galaxies (DSFGs) with rising SPIRE flux densities (S_500_>S_350_>S_250_; the so-called "500{mu}m risers") as an efficient way for identifying DSFGs at higher redshift (z>4). In this paper, we present a large Spitzer follow-up program of 300 Herschel ultrared DSFGs. We have obtained high-resolution Atacama Large Millimeter/submillimeter Array, Northern Extended Millimeter Array, and SMA data for 63 of them, which allow us to securely identify the Spitzer/IRAC counterparts and classify them as gravitationally lensed or unlensed. Within the 63 ultrared sources with high-resolution data, ~65% appear to be unlensed and ~27% are resolved into multiple components. We focus on analyzing the unlensed sample by directly performing multiwavelength spectral energy distribution modeling to derive their physical properties and compare with the more numerous z~2 DSFG population. The ultrared sample has a median redshift of 3.3, stellar mass of 3.7x10^11^M_{sun}_, star formation rate (SFR) of 730M_{sun}_/yr, total dust luminosity of 9.0x10^12^L_{sun}_, dust mass of 2.8x10^9^M_{sun}_, and V-band extinction of 4.0, which are all higher than those of the ALESS DSFGs. Based on the space density, SFR density, and stellar mass density estimates, we conclude that our ultrared sample cannot account for the majority of the star-forming progenitors of the massive, quiescent galaxies found in infrared surveys. Our sample contains the rarer, intrinsically most dusty, luminous, and massive galaxies in the early universe that will help us understand the physical drivers of extreme star formation.
- ID:
- ivo://CDS.VizieR/J/AJ/133/1560
- Title:
- Spitzer c2d small clouds and cores
- Short Name:
- J/AJ/133/1560
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a submillimeter survey of 53 low-mass dense cores with the Submillimeter High Angular Resolution Camera II (SHARC-II). The survey is a follow-up project to the Spitzer Legacy Program "From Molecular Cores to Planet-Forming Disks," with the purpose of creating a complete data set of nearby low-mass dense cores from the infrared to the millimeter. We present maps of 52 cores at 350um and three cores at 450um, two of which were observed at both wavelengths. Of these 52 cores, 41 were detected by SHARC-II; 32 contained one submillimeter source, while 9 contained multiple sources. For each submillimeter source detected, we report various source properties including source position, fluxes in various apertures, size, aspect ratio, and position angle.
- ID:
- ivo://CDS.VizieR/J/ApJ/669/493
- Title:
- Spitzer/Chandra YSOs in Serpens cloud core
- Short Name:
- J/ApJ/669/493
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present Spitzer and Chandra observations of the nearby (~260pc) embedded stellar cluster in the Serpens cloud core. We observed, using Spitzer's IRAC and MIPS instruments, in six wavelength bands from 3 to 70um, to detect thermal emission from circumstellar disks and protostellar envelopes and to classify stars using color-color diagrams and SEDs. These data are combined with Chandra observations to examine the effects of circumstellar disks on stellar X-ray properties. Young diskless stars were also identified from their increased X-ray emission. We have identified 138 YSOs in Serpens: 22 Class 0/I, 16 flat-spectrum, 62 Class II, 17 transition disk, and 21 Class III stars; 60 of these exhibit X-ray emission.
