- ID:
- ivo://CDS.VizieR/J/ApJ/835/55
- Title:
- AzTEC/ASTE survey at 1.1mm toward the SMC
- Short Name:
- J/ApJ/835/55
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The first 1.1mm continuum survey toward the Small Magellanic Cloud (SMC) was performed using the AzTEC instrument installed on the ASTE 10m telescope. This survey covered 4.5deg^2^ of the SMC with 1{sigma} noise levels of 5-12mJy/beam, and 44 extended objects were identified. The 1.1mm extended emission has good spatial correlation with Herschel 160{mu}m, indicating that the origin of the 1.1mm extended emission is thermal emission from a cold dust component. We estimated physical properties using the 1.1mm and filtered Herschel data (100, 160, 250, 350, and 500{mu}m). The 1.1mm objects show dust temperatures of 17-45K and gas masses of 4x10^3^-3x10^5^M_{sun}_, assuming single-temperature thermal emission from the cold dust with an emissivity index, {beta}, of 1.2 and a gas-to-dust ratio of 1000. These physical properties are very similar to those of giant molecular clouds (GMCs) in our galaxy and the Large Magellanic Cloud. The 1.1mm objects also displayed good spatial correlation with the Spitzer 24{mu}m and CO emission, suggesting that the 1.1mm objects trace the dense gas regions as sites of massive star formation. The dust temperature of the 1.1mm objects also demonstrated good correlation with the 24{mu}m flux connected to massive star formation. This supports the hypothesis that the heating source of the cold dust is mainly local star-formation activity in the 1.1mm objects. The classification of the 1.1mm objects based on the existence of star-formation activity reveals the differences in the dust temperature, gas mass, and radius, which reflects the evolution sequence of GMCs.
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Search Results
- ID:
- ivo://CDS.VizieR/J/MNRAS/423/529
- Title:
- AzTEC deep-field observations
- Short Name:
- J/MNRAS/423/529
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Instruments using arrays of many bolometers have become increasingly common in the past decade. The maps produced by such instruments typically include the filtering effects of the instrument as well as those from subsequent steps performed in the reduction of the data. Therefore interpretation of the maps is dependent upon accurately calculating the transfer function of the chosen reduction technique on the signal of interest. Many of these instruments use non-linear and iterative techniques to reduce their data because such methods can offer an improved signal-to-noise ratio over those that are purely linear, particularly for signals at scales comparable to that subtended by the array. We discuss a general approach for measuring the transfer function of principal component analysis on point sources that are small compared to the spatial extent seen by any single bolometer within the array. The results are applied to previously released AzTEC catalogues of the Cosmic Evolution Survey (COSMOS), Lockman Hole, Subaru XMM-Newton Deep Field, Great Observatories Origins Deep Survey (GOODS)-North and GOODS-South fields. Source flux density and noise estimates increase by roughly +10 per cent for fields observed while AzTEC was installed at the Atacama Submillimeter Telescope Experiment and +15-25 per cent while AzTEC was installed at the James Clerk Maxwell Telescope. Detection significance is, on average, unaffected by the revised technique. The revised photometry technique will be used in subsequent AzTEC releases.
- ID:
- ivo://CDS.VizieR/J/MNRAS/385/2225
- Title:
- AzTEC millimetre survey of COSMOS field
- Short Name:
- J/MNRAS/385/2225
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a 1.1mm wavelength imaging survey covering 0.3deg^2^ in the COSMOS field. These data, obtained with the AzTEC continuum camera on the James Clerk Maxwell Telescope, were centred on a prominent large-scale structure overdensity which includes a rich X-ray cluster at z>>0.73. A total of 50mm-galaxy candidates, with a significance ranging from 3.5 to 8.5sigma, are extracted from the central 0.15deg^2^ area which has a uniform sensitivity of 1.3mJy/beam. 16 sources are detected with S/N>=4.5, where the expected false-detection rate is zero, of which a surprisingly large number (9) have intrinsic (deboosted) fluxes >=5mJy at 1.1mm.
- ID:
- ivo://CDS.VizieR/J/MNRAS/401/160
- Title:
- AzTEC survey of the SHADES fields. I.
- Short Name:
- J/MNRAS/401/160
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first results from the largest deep extragalactic mm-wavelength survey undertaken to date. These results are derived from maps covering over 0.7deg^2^, made at {lambda}=1.1mm, using the AzTEC continuum camera mounted on the James Clerk Maxwell Telescope. The maps were made in the two fields originally targeted at {lambda}=850um with the Submillimetre Common-User Bolometer Array (SCUBA) in the SCUBA Half-Degree Extragalactic Survey (SHADES) project, namely the Lockman Hole East (mapped to a depth of 0.9-1.3mJy rms) and the Subaru/XMM-Newton Deep Field (mapped to a depth of 1.0-1.7mJy rms). The wealth of existing and forthcoming deep multifrequency data in these two fields will allow the bright mm source population revealed by these new wide-area 1.1mm images to be explored in detail in subsequent papers. Here, we present the maps themselves, a catalogue of 114 high-significance submillimetre galaxy detections, and a thorough statistical analysis leading to the most robust determination to date of the 1.1mm source number counts. These new maps, covering an area nearly three times greater than the SCUBA SHADES maps, currently provide the largest sample of cosmological volumes of the high-redshift Universe in the mm or sub-mm. Through careful comparison, we find that both the Cosmic Evolution Survey (COSMOS) and the Great Observatories Origins Deep Survey (GOODS) North fields, also imaged with AzTEC, contain an excess of mm sources over the new 1.1mm source-count baseline established here.
- ID:
- ivo://CDS.VizieR/J/MNRAS/426/1845
- Title:
- AzTEC survey of the SHADES fields. II.
- Short Name:
- J/MNRAS/426/1845
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Astronomical Thermal Emission Camera (AzTEC) 1.1mm survey of the two SCUBA HAlf Degree Extragalactic Survey (SHADES) fields is the largest (0.7deg^2^) blank-field millimetre-wavelength (mm-wavelength) survey undertaken to date at a resolution of 18arcsec and a depth of 1mJy. We have used the deep optical to radio multiwavelength data in the SHADES Lockman Hole East and SXDF/UDS fields to obtain galaxy identifications for 64 per cent (80 per cent including tentative identifications) of the 148 AzTEC-SHADES 1.1mm sources reported by Austermann et al., exploiting deep radio and 24um data complemented by methods based on 8um flux density and red optical-infrared (i-K) colour.
- ID:
- ivo://CDS.VizieR/J/other/IBVS/4459
- Title:
- Baade's variables in Sagitta and Cygnus
- Short Name:
- J/other/IBVS/445
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The tables below show identifications and precise positions for a group of variables found by Walter Baade (1928AN....232...65B) during his Bergedorfer days. The stars reported in this survey are of some historical interest because it was as a result of this work that Baade conceived ideas that led to his later recognition of the two stellar populations among Galactic stars (cf. Osterbrock, 1995, Journ. Hist. Astron., 26, 1).
- ID:
- ivo://CDS.VizieR/J/A+A/406/829
- Title:
- Background galaxies in the WSRT wide-field Survey
- Short Name:
- J/A+A/406/829
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have used the Westerbork array to carry out an unbiased wide-field survey for H I emission features, achieving an RMS sensitivity of about 18mJy/beam at a velocity resolution of 17km/s over 1800deg2 and between -1000<VHel<+6500 km/s. The primary data consists of auto-correlation spectra with an effective angular resolution of 49' FWHM. The survey region is centered approximately on the position of Messier 31 and is Nyquist-sampled over 60x30 deg in RAxDec. In this paper we present the results for our HI detections of external galaxies at positive Local Group Standard of Rest (LGSR) velocity. We detect 155 external galaxies in excess of 8 sigma in integrated HI flux density. Plausible optical associations are found within a 30' search radius for all but one of our HI detections in DSS images, although several are not previously catalogued or do not have published redshift determinations. Our detection without a DSS association is at low galactic latitude. Twenty-three of our objects are detected in HI for the first time. We classify almost half of our detections as "confused", since one or more companions is catalogued within a radius of 30' and a velocity interval of 400km/s. Nine of the detected galaxies fall so near the edges of the survey coverage (either spatially or in velocity) that their parameters can not be reliably determined. These nine objects are excluded from the enclosed table.
- ID:
- ivo://CDS.VizieR/J/A+A/587/A136
- Title:
- Balmer break galaxies at z<1.5 star formation
- Short Name:
- J/A+A/587/A136
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a spectroscopic study of the properties of 64 Balmer break galaxies that show signs of star formation. The studied sample of star-forming galaxies spans a redshift range from 0.094 to 1.475 with stellar masses in the range 10^8^-10^12^M_{sun}_. The sample also includes eight broad emission line galaxies with redshifts between 1.5<z<3.0. We derived star formation rates (SFRs) from emission line luminosities and investigated the dependence of the SFR and specific SFR (SSFR) on the stellar mass and color. Furthermore, we investigated the evolution of these relations with the redshift. We found that the SFR correlates with the stellar mass; our data is consistent with previous results from other authors in that there is a break in the correlation, which reveals the presence of massive galaxies with lower SFR values (i.e., decreasing star formation). We also note an anticorrelation for the SSFR with the stellar mass. Again in this case, our data is also consistent with a break in the correlation, revealing the presence of massive star-forming galaxies with lower SSFR values, thereby increasing the anticorrelation. These results might suggest a characteristic mass (M_0_) at which the red sequence could mostly be assembled. In addition, at a given stellar mass, high-redshift galaxies have on average higher SFR and SSFR values than local galaxies. Finally, we explored whether a similar trend could be observed with redshift in the SSFR-(u-B) color diagram, and we hypothesize that a possible (u-B)_0_ break color may define a characteristic color for the formation of the red sequence.
- ID:
- ivo://CDS.VizieR/II/63A
- Title:
- Balmer Lines Photometric Data
- Short Name:
- II/63A
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The purpose of the catalogue is to collect the photometric determination of the Balmer line-strength. Eleven different systems, including the measurements of one or more lines, from H{alpha} to H{delta}, have been found when surveying the literature. These include alpha, beta, gamma, alpha,beta, beta,gamma, and alpha,beta,gamma from various authors. The Stroemgren H{beta} photometry is not not included in this version.
1170. BAL QSOs from SDSS DR3
- ID:
- ivo://CDS.VizieR/J/ApJS/165/1
- Title:
- BAL QSOs from SDSS DR3
- Short Name:
- J/ApJS/165/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a total of 4784 unique broad absorption line quasars from the Sloan Digital Sky Survey Third Data Release (Cat. <VII/243>). An automated algorithm was used to match a continuum to each quasar and to identify regions of flux at least 10% below the continuum over a velocity range of at least 1000km/s in the CIV and MgII absorption regions. The model continuum was selected as the best-fit match from a set of template quasar spectra binned in luminosity, emission line width, and redshift, with the power-law spectral index and amount of dust reddening as additional free parameters. We characterize our sample through the traditional balnicity index and a revised absorption index, as well as through parameters such as the width, outflow velocity, fractional depth, and number of troughs.
