- ID:
- ivo://CDS.VizieR/J/ApJ/707/1201
- Title:
- LABOCA ECDFS Submillimeter Survey (LESS)
- Short Name:
- J/ApJ/707/1201
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a sensitive 870um survey of the Extended Chandra Deep Field South (ECDFS) combining 310hr of observing time with the Large Apex BOlometer Camera (LABOCA) on the APEX telescope. The LABOCA ECDFS Submillimetre Survey (LESS) covers the full 30'x30' field size of the ECDFS and has a uniform noise level of {sigma}_870um_~1.2mJy/beam. LESS is thus the largest contiguous deep submillimeter survey undertaken to date. The noise properties of our map show clear evidence that we are beginning to be affected by confusion noise. We present a catalog of 126 submillimeter galaxies (SMGs) detected with a significance level above 3.7{sigma}, at which level we expect five false detections given our map area of 1260arcmin^2^.
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Search Results
- ID:
- ivo://CDS.VizieR/J/ApJS/234/5
- Title:
- LaCoSSPAr in the Southern Galactic Cap. I.
- Short Name:
- J/ApJS/234/5
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a spectroscopic redshift catalog from the LAMOST Complete Spectroscopic Survey of Pointing Area (LaCoSSPAr) in the Southern Galactic Cap (SGC), which is designed to observe all sources (Galactic and extragalactic) by using repeating observations with a limiting magnitude of r=18.1mag in two 20deg^2^ fields. The project is mainly focusing on the completeness of LAMOST ExtraGAlactic Surveys (LEGAS) in the SGC, the deficiencies of source selection methods, and the basic performance parameters of the LAMOST telescope. In both fields, more than 95% of galaxies have been observed. A post-processing has been applied to the LAMOST 1D spectrum to remove the majority of remaining sky background residuals. More than 10000 spectra have been visually inspected to measure the redshift by using combinations of different emission/absorption features with an uncertainty of {sigma}_z_/(1+z)<0.001. In total, 1528 redshifts (623 absorption and 905 emission line galaxies) in Field A and 1570 redshifts (569 absorption and 1001 emission line galaxies) in Field B have been measured. The results show that it is possible to derive redshift from low S/N galaxies with our post-processing and visual inspection. Our analysis also indicates that up to one-fourth of the input targets for a typical extragalactic spectroscopic survey might be unreliable. The multi-wavelength data analysis shows that the majority of mid-infrared-detected absorption (91.3%) and emission line galaxies (93.3%) can be well separated by an empirical criterion of W2-W3=2.4. Meanwhile, a fainter sequence paralleled to the main population of galaxies has been witnessed both in Mr/W2-W3 and M*/W2-W3 diagrams, which could be the population of luminous dwarf galaxies but contaminated by the edge-on/highly inclined galaxies (~30%).
- ID:
- ivo://CDS.VizieR/J/MNRAS/468/1123
- Title:
- LAE among star-forming galaxies at z=2.5
- Short Name:
- J/MNRAS/468/1123
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We conducted a deep narrow-band imaging survey with the Subaru Prime Focus Camera on the Subaru Telescope and constructed a sample of Ly{alpha} emitters (LAEs) at z=2.53 in the UDS-CANDELS field, where a sample of H{alpha} emitters (HAEs) at the same redshift is already obtained from our previous narrow-band observation at near-infrared. The deep narrow-band and multibroad-band data allow us to find LAEs of stellar masses and star formation rates (SFRs) down to >=10^8^M_{sun}_ and >=0.2 M_{sun}_/yr, respectively. We show that the LAEs are located along the same mass-SFR sequence traced by normal star-forming galaxies such as HAEs, but towards a significantly lower mass regime. Likewise, LAEs seem to share the same mass-size relation with typical star-forming galaxies, except for the massive LAEs that tend to show significantly compact sizes. We identify a vigorous mass growth in the central part of LAEs: the stellar mass density in the central region of LAEs increases as their total galaxy mass grows. On the other hand, we see no Ly{alpha} line in emission for most of the HAEs. Rather, we find that the Ly{alpha} feature is either absent or in absorption (Ly{alpha} absorbers, LAAs), and its absorption strength may increase with reddening of the UV continuum slope. We demonstrate that a deep Ly{alpha} narrow-band imaging like this study is able to search for not only LAEs but also LAAs in a certain redshift slice. This work suggests that LAEs trace normal star-forming galaxies in the low-mas
- ID:
- ivo://CDS.VizieR/J/ApJ/863/92
- Title:
- LAE cand. at z~5.7 in the field of QSO J0148+0600
- Short Name:
- J/ApJ/863/92
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The observed scatter in intergalactic Ly{alpha} opacity at z<~6 requires large-scale fluctuations in the neutral fraction of the intergalactic medium (IGM) after the expected end of reionization. Post-reionization models that explain this scatter invoke fluctuations in either the ionizing ultraviolet background (UVB) or IGM temperature. These models make very different predictions, however, for the relationship between Ly{alpha} opacity and local density. Here, we test these models using Ly{alpha}-emitting galaxies (LAEs) to trace the density field surrounding the longest and most opaque known Ly{alpha} trough at z<6. Using deep Subaru Hyper Suprime-Cam narrowband imaging, we find a highly significant deficit of z~5.7 LAEs within 20h^-1^Mpc of the trough. The results are consistent with a model in which the scatter in Ly{alpha} opacity near z~6 is driven by large-scale UVB fluctuations, and disfavor a scenario in which the scatter is primarily driven by variations in IGM temperature. UVB fluctuations at this epoch present a boundary condition for reionization models, and may help shed light on the nature of the ionizing sources.
- ID:
- ivo://CDS.VizieR/J/ApJ/744/110
- Title:
- LAE galaxies between 2.1=<z<=3.1
- Short Name:
- J/ApJ/744/110
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We describe the results of a new, wide-field survey for z=3.1 Ly{alpha} emitters (LAEs) in the Extended Chandra Deep Field South (ECDF-S). By using a nearly top-hat 5010{AA} filter and complementary broadband photometry from the MUSYC survey, we identify a complete sample of 141 objects with monochromatic fluxes brighter than 2.4x10^-17^erg/cm^2^/s and observers-frame equivalent widths (EWs) greater than ~80{AA} (i.e., 20{AA} in the rest frame of Ly{alpha}). The bright end of this data set is dominated by X-ray sources and foreground objects with Galaxy Evolution Explorer detections, but when these interlopers are removed, we are still left with a sample of 130 LAE candidates, 39 of which have spectroscopic confirmations. This sample overlaps the set of objects found in an earlier ECDF-S survey, but due to our filter's redder bandpass, it also includes 68 previously uncataloged sources. We confirm earlier measurements of the z=3.1 LAE emission-line luminosity function and show that an apparent anticorrelation between EW and continuum brightness is likely due to the effect of correlated errors in our heteroskedastic data set. Finally, we compare the properties of z=3.1 LAEs to LAEs found at z=2.1. We show that in the ~1Gyr after z~3, the LAE luminosity function evolved significantly, with L* fading by ~0.4mag, the number density of sources with L>1.5x10^42^erg/s declining by ~50%, and the EW scale length contracting from 70^+7^_-5_{AA} to 50^+9^_-6_{AA}. When combined with literature results, our observations demonstrate that over the redshift range z~0 to z~4, LAEs contain less than ~10% of the star formation rate density of the universe.
- ID:
- ivo://CDS.VizieR/J/ApJ/753/95
- Title:
- LAE galaxies in the ECDF-S at z~2.1 and z~3.1
- Short Name:
- J/ApJ/753/95
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a rest-frame ultraviolet morphological analysis of 108 z~2.1 Ly{alpha} emitters (LAEs) in the Extended Chandra Deep Field South and compare it to a similar sample of 171 LAEs at z~3.1. Using Hubble Space Telescope images from the Galaxy Evolution from Morphology and SEDs survey, Great Observatories Origins Deep Survey, and Hubble Ultradeep Field, we measure size and photometric component distributions, where photometric components are defined as distinct clumps of UV-continuum emission. At both redshifts, >80% of LAEs have observed half-light radii <2kpc, but the median half-light radius rises from 0.95+/-0.04kpc at z=3.1 to 1.41+/-0.14kpc at z=2.1. A similar evolution is seen in the sizes of individual rest-UV components, but there is no evidence for evolution in the number of multi-component systems. In the z=2.1 sample, we see clear correlations between the size of an LAE and other physical properties derived from its spectral energy distribution (SED). LAEs are found to be larger for galaxies with higher stellar mass, star formation rate, and dust obscuration, but there is no evidence for a trend between equivalent width and half-light radius at either redshift. The presence of these correlations suggests that a wide range of objects are being selected by LAE surveys at z~2, including a significant fraction of objects for which a massive and moderately extended population of old stars underlies the young starburst giving rise to the Ly{alpha} emission.
- ID:
- ivo://CDS.VizieR/J/ApJ/706/762
- Title:
- LAEs at z~4.5 in the LALA Cetus field
- Short Name:
- J/ApJ/706/762
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a large sample of Ly{alpha}-emitting galaxies (LAEs) spectroscopically confirmed at redshift z~4.5, based on Inamori-Magellan Areal Camera and Spectrograph spectroscopic observations of candidate z~4.5 Ly{alpha}-emitting galaxies in the large area Lyman alpha (LALA) narrowband imaging survey Cetus field. We identify 110 of them as z~4.5 Ly{alpha} emitters based on single-line detections with no continuum emission blueward of the line. Six foreground galaxies are identified, either based on multiple lines or blueward continuum emission. The Ly{alpha} confirmation rate varies from <50% to 76% for candidates selected in different narrowband filters at slightly different redshifts. The sample includes many objects with equivalent widths (EWs)>~200{AA}. These large EW candidates are spectroscopically confirmed at the same rate as candidates with more modest EWs.
- ID:
- ivo://CDS.VizieR/J/ApJ/738/136
- Title:
- LAEs between 0.19<z<1.25 with GALEX grism
- Short Name:
- J/ApJ/738/136
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present optical spectroscopy of two samples of Galaxy Evolution Explorer grism selected Ly{alpha} emitters (LAEs): one at z=0.195-0.44 and the other at z=0.65-1.25. We have also observed a comparison sample of galaxies in the same redshift intervals with the same UV magnitude distributions but with no detected Ly{alpha}. We use the optical spectroscopy to eliminate active galactic nuclei and to obtain the optical emission-line properties of the samples. We compare the luminosities of the LAEs in the two redshift intervals and show that there is dramatic evolution in the maximum Ly{alpha} luminosity over z=0-1. Focusing on the z=0.195-0.44 samples alone, we show that there are tightly defined relations between all of the galaxy parameters and the rest-frame equivalent width (EW) of H{alpha}. The higher EW(H{alpha}) sources all have lower metallicities, bluer colors, smaller sizes, and less extinction, consistent with their being in the early stages of the galaxy formation process.
- ID:
- ivo://CDS.VizieR/J/ApJ/865/L1
- Title:
- LAEs discovered with ultra-deep MUSE sp. in UDF
- Short Name:
- J/ApJ/865/L1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using an ultra-deep blind survey with the MUSE integral field spectrograph on the European Southern Observatory Very Large Telescope, we obtain spectroscopic redshifts to a depth never before explored: galaxies with observed magnitudes m_AB_>~30-32. Specifically, we detect objects via Ly{alpha} emission at 2.9<z<6.7 without individual continuum counterparts in areas covered by the deepest optical/near-infrared imaging taken by the Hubble Space Telescope, the Hubble Ultra Deep Field. In total, we find 102 such objects in 9 square arcminutes at these redshifts. Detailed stacking analyses confirm the Ly{alpha} emission as well as the 1216 {AA} breaks and faint ultraviolet continua (M_UV_~-15). This makes them the faintest spectroscopically confirmed objects at these redshifts, similar to the sources believed to reionize the universe. A simple model for the expected fraction of detected/undetected Ly{alpha} emitters as a function of luminosity is consistent with these objects being the high-equivalent width tail of the normal Ly{alpha}-emitter population at these redshifts.
- ID:
- ivo://org.gavo.dc/lamost5/q/ssa
- Title:
- LAMOST DR5 survey spectra
- Short Name:
- LAMOST DR5 SSAP
- Date:
- 27 Dec 2024 08:31:13
- Publisher:
- The GAVO DC team
- Description:
- This services provides 1D spectra from DR5 of LAMOST (Large Sky Area Multi-Object Fiber Spectroscopic Telescope) through SSAP; data is served both in VO-standard SDM and, via datalink, the original SDSS-inspired FITS described in http://dr5.lamost.org/doc/data-production-description .
