- ID:
- ivo://CDS.VizieR/J/ApJ/751/138
- Title:
- VRIJHK photometry of IRAS 09149-4743 region
- Short Name:
- J/ApJ/751/138
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The RCW41 star-forming region is embedded within the Vela Molecular Ridge, hosting a massive stellar cluster surrounded by a conspicuous HII region. Understanding the role of interstellar magnetic fields and studying the newborn stellar population is crucial to building a consistent picture of the physical processes acting on this kind of environment. We carried out a detailed study of the interstellar polarization toward RCW41 with data from an optical and near-infrared polarimetric survey. Additionally, deep near-infrared images from the 3.5 meter New Technology Telescope were used to study the photometric properties of the embedded young stellar cluster, revealing several YSO candidates. By using a set of pre-main-sequence isochrones, a mean cluster age in the range 2.5-5.0 million years was determined, and evidence of sequential star formation was revealed. An abrupt decrease in R-band polarization degree was noticed toward the central ionized area, probably due to low grain alignment efficiency caused by the turbulent environment and/or the weak intensity of magnetic fields. The distortion of magnetic field lines exhibits dual behavior, with the mean orientation outside the area approximately following the borders of the star-forming region and directed radially toward the cluster inside the ionized area, in agreement with simulations of expanding H II regions. The spectral dependence of polarization allowed a meaningful determination of the total-to-selective extinction ratio by fittings of the Serkowski relation. Furthermore, a large rotation of polarization angle as a function of wavelength was detected toward several embedded stars.
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Search Results
- ID:
- ivo://CDS.VizieR/J/ApJ/766/114
- Title:
- Water and methanol masers in G75.78+0.34
- Short Name:
- J/ApJ/766/114
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present subarcsecond observations toward the massive star-forming region G75.78+0.34. We used the Very Large Array to study the centimeter continuum and H_2_O and CH_3_OH maser emission, and the Owens Valley Radio Observatory and Submillimeter Array to study the millimeter continuum and recombination lines (H40{alpha} and H30{alpha}). We found radio continuum emission at all wavelengths, coming from three components: (1) a cometary ultracompact (UC) H II region with an electron density ~3.7x10^4^/cm3, excited by a B0 type star, and with no associated dust emission; (2) an almost unresolved UCH II region (EAST), located ~6" to the east of the cometary UCH II region, with an electron density ~1.3x10^5^/cm3, and associated with a compact dust clump detected at millimeter and mid-infrared wavelengths; and (3) a compact source (CORE), located ~2" to the southwest of the cometary arc, with a flux density increasing with frequency, and embedded in a dust condensation of 30M_{sun}_. The CORE source is resolved into two compact and unresolved sources which can be well fit by two homogeneous hypercompact H II regions each one photoionized by a B0.5 zero-age main sequence star, or by free-free radiation from shock-ionized gas resulting from the interaction of a jet/outflow system with the surrounding environment. The spatial distribution and kinematics of water masers close to the CORE-N and S sources, together with excess emission at 4.5{mu}m and the detected dust emission, suggest that the CORE source is a massive protostar driving a jet/outflow.
- ID:
- ivo://CDS.VizieR/J/A+A/434/613
- Title:
- Water maser survey of methanol maser sources
- Short Name:
- J/A+A/434/613
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- High sensitivity observations of the 22GHz water maser emission have been carried out with the Effelsberg 100m radio telescope. The observed sample was 79 candidate high-mass protostellar objects from a flux-limited sample of 6.7GHz methanol sources (Szymczak et al., 2002A&A...392..277S). Water maser emission was found in 41 sources of which 28 were not previously catalogued.
- ID:
- ivo://CDS.VizieR/J/A+A/466/137
- Title:
- Westerlund 2 JHKs photometry
- Short Name:
- J/A+A/466/137
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Photometry for the stars detected with SOFI, NTT in J, H and Ks in the field containing the massive cluster Westerlund 2 (also know as RCW 49) associated with the HII region Gum29. For each star detected in all three bands the table contains the ID, equatorial coordinates, J, H and Ks magnitude and photometric errors. For the stars detected only in Ks or in H and Ks the magnitude and photometric error fields in the absent bands are filled with the values 99.99 and 9.999 respectively.
- ID:
- ivo://CDS.VizieR/J/A+A/589/A44
- Title:
- W51 Main NH_3_ and CH_3_OH data cubes
- Short Name:
- J/A+A/589/A44
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper is the third in a series of NH_3_ multilevel imaging studies in well-known, high-mass star-forming regions. The main goal is to characterize kinematics and physical conditions of (hot and dense) circumstellar molecular gas around O-type young stars. We want to map at subarcsecond resolution highly excited inversion lines of NH_3_ in the high-mass star-forming region W51 Main (distance = 5.4kpc), which is an ideal target to constrain theoretical models of high-mass star formation. Using the Karl Jansky Very Large Array (JVLA), we mapped the hot and dense molecular gas in W51 Main with ~0.2"-0.3" angular resolution in five metastable (J = K) inversion transitions of ammonia (NH_3_): (J,K) = (6, 6), (7, 7), (9, 9), (10, 10), and (13, 13). These lines arise from energy levels between ~400K and ~1700K above the ground state. We also made maps of the (free-free) continuum emission at frequencies between 25 and 36GHz.
- ID:
- ivo://CDS.VizieR/J/ApJS/180/283
- Title:
- WMAP five-year source catalog
- Short Name:
- J/ApJS/180/283
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the list of point sources found in the Wilkinson Microwave Anisotropy Probe (WMAP) five-year maps. The technique used in the first-year and three-year analyses now finds 390 point sources, and the five-year source catalog is complete for regions of the sky away from the Galactic plane to a 2Jy limit, with SNR>4.7 in all bands in the least covered parts of the sky. The noise at high frequencies is still mainly radiometer noise, but at low frequencies the cosmic microwave background (CMB) anisotropy is the largest uncertainty. A separate search of CMB-free V-W maps finds 99 sources of which all but one can be identified with known radio sources. The sources seen by WMAP are not strongly polarized. Many of the WMAP sources show significant variability from year to year, with more than a 2:1 range between the minimum and maximum fluxes.
- ID:
- ivo://CDS.VizieR/J/A+A/567/L5
- Title:
- W3(OH) high angular resolution 7mm images
- Short Name:
- J/A+A/567/L5
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Recent high angular resolution radio observations of the ultracompact Hii region W3(OH) confirm the presence of an extremely compact (0.05"), time-variable source near its center. We use new, sensitive high angular resolution observations of radio continuum and recombination lines to study the compact source in W3(OH) and the ultracompact HII region itself. We reduced and analyzed extensive Jansky Very Large Array observations of W3(OH) in the continuum at 41.0GHz and in the H54{alpha} and He54{alpha} lines.
- ID:
- ivo://CDS.VizieR/J/MNRAS/420/3091
- Title:
- Wolf-Rayet population in NGC 5068
- Short Name:
- J/MNRAS/420/3091
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a narrow-band Very Large Telescope/Focal Reduced Low-dispersion Spectrograph #1 imaging survey of the SAB(rs)cd spiral galaxy NGC 5068, located at a distance of 5.45Mpc, from which 160 candidate Wolf-Rayet sources have been identified, of which 59 cases possess statistically significant {lambda}4686 excesses. Follow-up Gemini Multi-Object Spectrograph spectroscopy of 64 candidates, representing 40 per cent of the complete photometric catalogue, confirms Wolf-Rayet signatures in 30 instances, corresponding to a 47 per cent success rate. 21 out of 22 statistically significant photometric sources are spectroscopically confirmed.
- ID:
- ivo://CDS.VizieR/J/A+AS/136/35
- Title:
- WR galaxies and HII regions catalog
- Short Name:
- J/A+AS/136/35
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a new compilation of Wolf-Rayet (WR) galaxies and extra-galactic HII regions showing broad He II {lambda}4686 emission drawn from the literature. Relevant information on the presence of other broad emission lines (N III {lambda}4640, C IV {lambda}5808 and other) from WR stars of WN and WC subtypes, and other existing broad nebular lines is provided. In total we include 139 known WR galaxies. Among these, 57 objects show both broad He II {lambda}4686 and C IV {lambda}5808 features. In addition to the broad (stellar) He II {lambda}4686 emission, a nebular He II component is well established (suspected) in 44 (54) objects. We find 19 extra-galactic HII regions without WR detections showing nebular He II {lambda}4686 emission. The present sample can be used for a variety of studies on massive stars, interactions of massive stars with the ISM, stellar populations, starburst galaxies etc. The data is accessible electronically and will be updated periodically
- ID:
- ivo://CDS.VizieR/J/A+A/418/841
- Title:
- XMM-Newton observations of N11 in the LMC
- Short Name:
- J/A+A/418/841
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using the XMM-Newton observatory, we have observed the giant H II region N11 of the LMC. The field includes three OB associations LH9, LH9, and LH13. Our XMM observations included parallel observations with the OM camera that provided us with unique UV and optical photometry of more than 6000 sources. In this paper we present the photometrical data for these sources as well as their cross-identifications with several catalogues.
