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4141. Multiwavelength view of blazar PKS 2155-304
ID:
ivo://CDS.VizieR/J/A+A/539/A149
Title:
Multiwavelength view of blazar PKS 2155-304
Short Name:
J/A+A/539/A149
Date:
21 Oct 2021
Publisher:
CDS
Description:
Multiwavelength (MWL) observations of the blazar PKS 2155-304 during two weeks in July and August 2006, the period when two exceptional flares at very high energies (VHE, E>=100GeV) occurred, provide a detailed picture of the evolution of its emission. The complete data set from this campaign is presented, including observations in VHE gamma-rays (H.E.S.S.), X-rays (RXTE, CHANDRA, SWIFT XRT), optical (SWIFT UVOT, Bronberg, Watcher, ROTSE), and in the radio band (NRT, HartRAO, ATCA). Optical and radio light curves from 2004 to 2008 are compared to the available VHE data from this period, to put the 2006 campaign into the context of the long-term evolution of the source. The data set offers a close view of the evolution of the source on different time scales and yields new insights into the properties of the emission process. The predictions of synchrotron self-Compton (SSC) scenarios are compared to the MWL data, with the aim of describing the dominant features in the data down to the hour time scale. The spectral variability in the X-ray and VHE bands is explored and correlations between the integral fluxes at different wavelengths are evaluated. SSC modelling is used to interpret the general trends of the varying spectral energy distribution.
4142. 16{mu}m imaging around the HDF-N
ID:
ivo://CDS.VizieR/J/ApJ/634/128
Title:
16{mu}m imaging around the HDF-N
Short Name:
J/ApJ/634/128
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a pilot study of 16{mu}m imaging within the GOODS northern field. Observations were obtained using the "peak-up" imaging capability of the Spitzer IRS. We survey 35arcmin^2^ to an average 3{sigma} depth of 0.075mJy and detect 149 sources.
4143. 500{mu}m-risers sources
ID:
ivo://CDS.VizieR/J/A+A/614/A33
Title:
500{mu}m-risers sources
Short Name:
J/A+A/614/A33
Date:
21 Oct 2021
Publisher:
CDS
Description:
Context. Over the last decade a large number of dusty star-forming galaxies has been discovered up to redshift z=2-3 and recent studies have attempted to push the highly confused Herschel SPIRE surveys beyond that distance. To search for z>=4 galaxies they often consider the sources with fluxes rising from 250{mu}m to 500{mu}m (so-called "500{mu}m-risers"). Herschel surveys offer a unique opportunity to efficiently select a large number of these rare objects, and thus gain insight into the prodigious star-forming activity that takes place in the very distant Universe. Aims. We aim to implement a novel method to obtain a statistical sample of 500{mu}m-risers and fully evaluate our selection inspecting different models of galaxy evolution. Methods. We consider one of the largest and deepest Herschel surveys, the Herschel Virgo Cluster Survey. We develop a novel selection algorithm which links the source extraction and spectral energy distribution fitting. To fully quantify selection biases we make end-to-end simulations including clustering and lensing. Results. We select 133 500{mu}m-risers over 55deg^2^, imposing the criteria: S_500_>S_350_>S_250_, S_250_>13.2mJy and S_500_>30mJy. Differential number counts are in fairly good agreement with models, displaying a better match than other existing samples. The estimated fraction of strongly lensed sources is 24_+6_^-5^% based on models.Conclusions. We present the faintest sample of 500{mu}m-risers down to S_250_=13.2mJy. We show that noise and strong lensing have an important impact on measured counts and redshift distribution of selected sources. We estimate the flux-corrected star formation rate density at 4<z<5 with the 500{mu}m-risers and find it to be close to the total value measured in far-infrared. This indicates that colour selection is not a limiting effect to search for the most massive, dusty z>4 sources.
4144. 16{mu}m sources in the NOAO Bootes field
ID:
ivo://CDS.VizieR/J/ApJ/634/L1
Title:
16{mu}m sources in the NOAO Bootes field
Short Name:
J/ApJ/634/L1
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using the 16{mu}m peak-up imager on the Infrared Spectrograph (IRS) on Spitzer, we present a serendipitous survey of 0.0392{deg}^2^ within the area of the NOAO Deep Wide-Field Survey in Bootes. Combining our results with the available Multiband Imaging Photometer for Spitzer (MIPS) 24{mu}m survey of this area, we produce a catalog of 150 16{mu}m sources brighter than 0.18mJy (3{sigma}) for which we derive measures or limits on the 16{mu}m/24{mu}m colors. Such colors are especially useful in determining redshifts for sources whose mid-infrared spectra contain strong emission or absorption features that characterize these colors as a function of redshift.
4145. 3{mu}m survey of the Chamaeleon I dark cloud
ID:
ivo://CDS.VizieR/J/AJ/121/2673
Title:
3{mu}m survey of the Chamaeleon I dark cloud
Short Name:
J/AJ/121/2673
Date:
21 Oct 2021
Publisher:
CDS
Description:
We describe an L-band photometric survey of ~0.5deg^2^ of the Chamaeleon I dark cloud. The survey has a completeness limit of L<11.0. Our survey detects 124 sources, including all known pre-main-sequence stars with L<=11. The fraction of sources with near-IR excess emission is 58%+/-4% for K=9-11. Cha I sources have bluer H-K and K-L colors than pre-main-sequence stars in Taurus-Auriga. These sources also have a strong correlation between EW(H{alpha} and K-L. Stars with K-L<=0.6 have weak H{alpha} emission; stars with K-L>=0.6 have strong H{alpha]mission. Because many Cha I sources are heavily reddened, this division between weak emission T Tauri stars and classical T Tauri stars occurs at a redder K-L than in Taurus-Auriga. We acquired L-band photometry of Cha I sources and standard stars using the South Pole Infrared Explorer (SPIREX) during the 1999 March-October observing season. The SPIREX 60cm telescope developed by CARA for observations at the South Pole was equipped with the NOAO/KPNO Abu infrared camera, which includes a first generation 1024x1024 InSb detector array.
4146. MUSE and HFFs Photometry of A2744
ID:
ivo://CDS.VizieR/J/MNRAS/473/663
Title:
MUSE and HFFs Photometry of A2744
Short Name:
J/MNRAS/473/663
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present an analysis of Multi Unit Spectroscopic Explorer (MUSE) observations obtained on the massive Frontier Fields (FFs) cluster A2744. This new data set covers the entire multiply imaged region around the cluster core. The combined catalogue consists of 514 spectroscopic redshifts (with 414 new identifications). We use this redshift information to perform a strong-lensing analysis revising multiple images previously found in the deep FF images, and add three new MUSE-detected multiply imaged systems with no obvious Hubble Space Telescope counterpart. The combined strong-lensing constraints include a total of 60 systems producing 188 images altogether, out of which 29 systems and 83 images are spectroscopically confirmed, making A2744 one of the most well-constrained clusters to date. Thanks to the large amount of spectroscopic redshifts, we model the influence of substructures at larger radii, using a parametrization including two cluster-scale components in the cluster core and several group scale in the outskirts. The resulting model accurately reproduces all the spectroscopic multiple systems, reaching an rms of 0.67-arcsec in the image plane. The large number of MUSE spectroscopic redshifts gives us a robust model, which we estimate reduces the systematic uncertainty on the 2D mass distribution by up to ~2.5 times the statistical uncertainty in the cluster core. In addition, from a combination of the parametrization and the set of constraints, we estimate the relative systematic uncertainty to be up to 9 per cent at 200kpc.
4147. MUSE 3D view of HDF-S
ID:
ivo://CDS.VizieR/J/A+A/575/A75
Title:
MUSE 3D view of HDF-S
Short Name:
J/A+A/575/A75
Date:
21 Oct 2021
Publisher:
CDS
Description:
We observed Hubble Deep Field South with the new panoramic integral-field spectrograph MUSE that we built and have just commissioned at the VLT. The data cube resulting from 27h of integration covers one arcmin^2^ field of view at an unprecedented depth with a 1{sigma} emission-line surface brightness limit of 1x10^-19^erg/s/cm2/arcsec2, and contains ~90000 spectra. We present the combined and calibrated data cube, and we performed a first-pass analysis of the sources detected in the Hubble Deep Field South imaging. We measured the redshifts of 189 sources up to a magnitude I_814_=29.5, increasing the number of known spectroscopic redshifts in this field by more than an order of magnitude. We also discovered 26 Ly{alpha} emitting galaxies that are not detected in the HST WFPC2 deep broad-band images. The intermediate spectral resolution of 2.3{AA} allows us to separate resolved asymmetric Ly{alpha} emitters, [OII]3727 emitters, and [CIII]1908 emitters, and the broad instantaneous wavelength range of 4500{AA} helps to identify single emission lines, such as [OIII]5007, H{beta}, and H{alpha}, over a very wide redshift range. We also show how the three-dimensional information of MUSE helps to resolve sources that are confused at ground-based image quality. Overall, secure identifications are provided for 83% of the 227 emission line sources detected in the MUSE data cube and for 32% of the 586 sources identified in the HST catalogue. The overall redshift distribution is fairly flat to z=6.3, with a reduction between z=1.5 to 2.9, in the well-known redshift desert. The field of view of MUSE also allowed us to detect 17 groups within the field. We checked that the number counts of [OII]3727 and Ly{alpha} emitters are roughly consistent with predictions from the literature. Using two examples, we demonstrate that MUSE is able to provide exquisite spatially resolved spectroscopic information on the intermediate-redshift galaxies present in the field. This unique data set can be used for a wide range of follow-up studies. We release the data cube, the associated products, and the source catalogue with redshifts, spectra, and emission-line fluxes.
4148. MUSYC deep near-infrared imaging
ID:
ivo://CDS.VizieR/J/AJ/134/1103
Title:
MUSYC deep near-infrared imaging
Short Name:
J/AJ/134/1103
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present deep near-infrared JHK imaging of four 10x10 fields. The observations were carried out as part of the Multiwavelength Survey by Yale-Chile (MUSYC) with ISPI on the CTIO 4m telescope. The typical point-source limiting depths are J~22.5, H~21.5, and K~21 (5{sigma}; Vega). The effective seeing in the final images is 1.0". We combine these data with MUSYC UBVRIz imaging to create K-selected catalogs that are unique for their uniform size, depth, filter coverage, and image quality.
4149. MUSYC optical imaging in ECDF-S
ID:
ivo://CDS.VizieR/J/ApJS/189/270
Title:
MUSYC optical imaging in ECDF-S
Short Name:
J/ApJS/189/270
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present deep optical 18-medium-band photometry from the Subaru telescope over the ~30'x30' Extended Chandra Deep Field-South, as part of the Multiwavelength Survey by Yale-Chile (MUSYC). This field has a wealth of ground- and space-based ancillary data, and contains the GOODS-South field and the Hubble Ultra Deep Field. We combine the Subaru imaging with existing UBVRIzJHK and Spitzer IRAC images to create a uniform catalog. Detecting sources in the MUSYC "BVR" image we find ~40,000 galaxies with R_AB_<25.3, the median 5{sigma} limit of the 18 medium bands. Photometric redshifts are determined using the EAzY code and compared to ~2000 spectroscopic redshifts in this field. The medium-band filters provide very accurate redshifts for the (bright) subset of galaxies with spectroscopic redshifts, particularly at 0.1<z<1.2 and at z~>3.5. For 0.1<z<1.2, we find a 1{sigma} scatter in {DELTA}z/(1+z) of 0.007, similar to results obtained with a similar filter set in the COSMOS field. As a demonstration of the data quality, we show that the red sequence and blue cloud can be cleanly identified in rest-frame color-magnitude diagrams at 0.1<z<1.2. We find that ~20% of the red sequence galaxies show evidence of dust emission at longer rest-frame wavelengths. The reduced images, photometric catalog, and photometric redshifts are provided through the public MUSYC Web site (http://www.astro.yale.edu/MUSYC/).
4150. MUSYC: optical source catalog
ID:
ivo://CDS.VizieR/J/ApJS/162/1
Title:
MUSYC: optical source catalog
Short Name:
J/ApJS/162/1
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present UBVRIz' optical images taken with MOSAIC on the CTIO 4m telescope of the 0.32{deg}^2^ Extended Hubble Deep Field-South. This is one of four fields comprising the MUSYC survey, which is optimized for the study of galaxies at z=3, active galactic nucleus (AGN) demographics, and Galactic structure. Our methods used for astrometric calibration, weighted image combination, and photometric calibration in AB magnitudes are described. We calculate corrected aperture photometry and its uncertainties and find through tests that these provide a significant improvement upon standard techniques. Our photometric catalog of 62,968 objects is complete to a total magnitude of R_AB_=25, with R-band counts consistent with results from the literature.