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2001. Las Campanas Infrared Survey. V.
ID:
ivo://CDS.VizieR/J/MNRAS/361/525
Title:
Las Campanas Infrared Survey. V.
Short Name:
J/MNRAS/361/525
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present deep Keck spectroscopy, using the Deep Imaging Multi-Object Spectrograph and the Low-Resolution Imaging Spectrometer spectrographs, of a large and representative sample of 67 extremely red objects (EROs) to H=20.5 in three fields (SSA22, Chandra Deep Field South and NTT Deep Field) drawn from the Las Campanas Infrared Survey (LCIRS). Using the colour cut (I-H)>3.0 (Vega magnitudes) adopted in earlier papers in this series, we verify the efficiency of this selection for locating and studying distant old sources. Spectroscopic redshifts are determined for 44 sources, of which only two are contaminating low-mass stars. When allowance is made for incompleteness, the spectroscopic redshift distribution closely matches that predicted earlier on the basis of photometric data.
2002. Las Campanas Redshift Survey
ID:
ivo://CDS.VizieR/VII/203
Title:
Las Campanas Redshift Survey
Short Name:
VII/203
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Las Campanas Redshift Survey (LCRS) consists of 26,418 redshifts of galaxies selected from a CCD-based catalog obtained in the R band. The survey covers over 700deg^2 in six strips, each 1.5x80deg, three each in the north and south Galactic caps. The median redshift in the survey is about 30,000km/s. Essential features of the galaxy selection and redshift measurement methods are described and tabulated here. These details are important for subsequent analysis of the LCRS data. Two-dimensional representations of the redshift distributions reveal many repetitions of voids, on the scale of about 5000km/s, sharply bounded by large walls of galaxies as seen in nearby surveys. Statistical investigations of the mean galaxy properties and of clustering on the large scale are reported elsewhere. These include studies of the luminosity function, power spectrum in two and three dimensions, correlation function, pairwise velocity distribution, identification of large-scale structures, and a group catalog.
2003. LBDS Hercules sample griJHK photometry
ID:
ivo://CDS.VizieR/J/MNRAS/317/801
Title:
LBDS Hercules sample griJHK photometry
Short Name:
J/MNRAS/317/801
Date:
21 Oct 2021
Publisher:
CDS
Description:
The results are presented of an extensive programme of optical and infrared imaging of radio sources in a complete subsample of the Leiden-Berkeley Deep Survey. The LBDS Hercules sample consists of 72 sources observed at 1.4GHz, with flux densities S_1.4_>=1.0mJy, in a 1.2deg^2^ region of Hercules. This sample is almost completely identified in the g, r, i and K bands, with some additional data available at J and H. The magnitude distributions peak at r~22mag, K~6mag and extend down to r~26mag, K~21mag. The K-band magnitude distributions for the radio galaxies and quasars are compared with those of other radio surveys. At S_1.4GHz_<~1Jy, the K-band distribution does not change significantly with radio flux density. The sources span a broad range of colours, with several being extremely red (r-K>~6). Though small, this is the most optically complete sample of mJy radio sources available at 1.4GHz, and is ideally suited for studying the evolution of the radio luminosity function out to high redshifts.
2004. LBDS-Lynx region GMRT 150-MHz obs.
ID:
ivo://CDS.VizieR/J/MNRAS/405/436
Title:
LBDS-Lynx region GMRT 150-MHz obs.
Short Name:
J/MNRAS/405/436
Date:
21 Oct 2021
Publisher:
CDS
Description:
It has been known for nearly three decades that high-redshift radio galaxies exhibit steep radio spectra, and hence ultrasteep spectrum radio sources provide candidates for high-redshift radio galaxies. Nearly all radio galaxies with z>3 have been found using this redshift-spectral index correlation. We have started a programme with the Giant Metrewave Radio Telescope (GMRT) to exploit this correlation at flux density levels about 10 to 100 times deeper than the known high-redshift radio galaxies which were identified primarily using the already available radio catalogues. In our programme, we have obtained deep, high-resolution radio observations at 150MHz with GMRT for several "deep" fields which are well studied at higher radio frequencies and in other bands of the electromagnetic spectrum, with an aim to detect candidate high-redshift radio galaxies. In this paper we present results from the deep 150-MHz observations of the LBDS-Lynx field (Leiden-Berkeley Deep Survey), which has been already imaged at 327, 610 and 1412MHz with the Westerbork Synthesis Radio Telescope and at 1400 and 4860MHz with the Very Large Array.
2005. LCID project. I. Cetus and Tucana variables
ID:
ivo://CDS.VizieR/J/ApJ/699/1742
Title:
LCID project. I. Cetus and Tucana variables
Short Name:
J/ApJ/699/1742
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the first study of the variable star populations in the isolated dwarf spheroidal galaxies (dSphs) Cetus and Tucana. Based on Hubble Space Telescope images obtained with the Advanced Camera for Surveys in the F475W and F814W bands, we identified 180 and 371 variables in Cetus and Tucana, respectively. The vast majority are RR Lyrae stars. In Cetus, we also found three anomalous Cepheids (ACs), four candidate binaries and one candidate long-period variable (LPV), while six ACs and seven LPV candidates were found in Tucana. Of the RR Lyrae stars, 147 were identified as fundamental mode (RRab) and only eight as first-overtone mode (RRc) in Cetus, with mean periods of 0.614 and 0.363 day, respectively. In Tucana, we found 216 RRab and 82 RRc giving mean periods of 0.604 and 0.353 day. These values place both galaxies in the so-called Oosterhoff Gap, as is generally the case for dSph. We found numerous RR Lyrae variables pulsating in both modes simultaneously (RRd): 17 in Cetus and 60 in Tucana. We provide the photometry and pulsation parameters for all the variables, and compare the latter with values from the literature for well studied dSph of the Local Group and Galactic globular clusters. The parallel WFPC2 fields were also searched for variables, as they lie well within the tidal radius of Cetus, and at its limit in the case of Tucana. No variables were found in the latter, while 15 were discovered in the outer field of Cetus (11 RRab, three RRc, and one RRd), even though the lower signal-to-noise ratio of the observations did not allow us to measure their periods accurately. We provide their coordinates and approximate properties for completeness.
2006. LCID project. II. Variables in IC1613
ID:
ivo://CDS.VizieR/J/ApJ/712/1259
Title:
LCID project. II. Variables in IC1613
Short Name:
J/ApJ/712/1259
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of a new search for variable stars in the Local Group (LG) isolated dwarf galaxy IC 1613, based on 24 orbits of F475W and F814W photometry from the Advanced Camera for Surveys (ACS) on board the Hubble Space Telescope. We detected 259 candidate variables in this field, of which only 13 (all of them bright Cepheids) were previously known. Out of the confirmed variables, we found 90 RR Lyrae stars, 49 classical Cepheids (including 36 new discoveries), and 38 eclipsing binary stars for which we could determine a period. The RR Lyrae include 61 fundamental (RRab) and 24 first-overtone (FO, RRc) pulsators, and five pulsating in both modes simultaneously (RRd). As for the majority of LG dwarfs, the mean periods of the RRab and RRc (0.611 and 0.334 days, respectively) as well as the fraction of overtone pulsators (f_c_=0.28) place this galaxy in the intermediate regime between the Oosterhoff types. From their position on the period-luminosity diagram and light-curve morphology, we can unambiguously classify 25 and 14 Cepheids as fundamental and FO mode pulsators, respectively. Another two are clearly second-overtone Cepheids, the first ones to be discovered beyond the Magellanic Clouds. Among the remaining candidate variables, five were classified as {delta}-Scuti and five as long-period variables. Most of the others are located on the main sequence, the majority of them likely eclipsing binary systems, although some present variations similar to pulsating stars.
2007. LCID project VIII. Cepheids of Leo A
ID:
ivo://CDS.VizieR/J/MNRAS/432/3047
Title:
LCID project VIII. Cepheids of Leo A
Short Name:
J/MNRAS/432/3047
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of a new search for variable stars in the Local Group dwarf galaxy Leo A, based on deep photometry from the Advanced Camera for Surveys onboard the Hubble Space Telescope. We detected 166 bona fide variables in our field, of which about 60% are new discoveries and 33 candidate variables. Of the confirmed variables, we found 156 Cepheids, but only 10 RR Lyrae stars despite nearly 100percent completeness at the magnitude of the horizontal branch. The RR Lyrae stars include seven fundamental and three first-overtone pulsators, with mean periods of 0.636 and 0.366d, respectively. From their position on the period-luminosity (PL) diagram and light-curve morphology, we classify 91, 58 and 4 Cepheids as fundamental, first-overtone and second-overtone mode Classical Cepheids (CC), respectively, and two as Population II Cepheids. However, due to the low metallicity of Leo A, about 90percent of the detected Cepheids have periods shorter than 1.5d. Comparison with theoretical models indicate that some of the fainter stars classified as CC could be Anomalous Cepheids. We estimate the distance to Leo A using the tip of the red giant branch (TRGB) and various methods based on the photometric and pulsational properties of the Cepheids and RR Lyrae stars. The distances obtained with the TRGB and RR Lyrae stars agree well with each other while that from the Cepheid PL relations is somewhat larger, which may indicate a mild metallicity effect on the luminosity of the short-period Cepheids. Due to its very low metallicity, Leo A thus serves as a valuable calibrator of the metallicity dependences of the variable star luminosities.
2008. LCRS loose groups of galaxies
ID:
ivo://CDS.VizieR/J/ApJS/130/237
Title:
LCRS loose groups of galaxies
Short Name:
J/ApJS/130/237
Date:
21 Oct 2021
Publisher:
CDS
Description:
A "friends-of-friends" percolation algorithm has been used to extract a catalog of {delta}n/n=80 density enhancements (groups) from the six slices of the Las Campanas Redshift Survey (LCRS). The full catalog contains 1495 groups and includes 35% of the LCRS galaxy sample. A clean sample of 394 groups has been derived by culling groups from the full sample that either are too close to a slice edge, have a crossing time greater than a Hubble time, have a corrected velocity dispersion of zero, or contain a 55"-'orphan' (a galaxy with a mock redshift that was excluded from the original LCRS redshift catalog due to its proximity to another galaxy, i.e., within 55").
2009. LDSS Deep Redshift Survey
ID:
ivo://CDS.VizieR/J/MNRAS/244/408
Title:
LDSS Deep Redshift Survey
Short Name:
J/MNRAS/244/408
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using a multisplit spectrograph, LDSS, we have obtained intermediate dispersion spectroscopy for a new sample of 149 faint objects selected randomly from the magnitude range 21<=bJ<=22.5 in three high-latitude fields.
2010. LEDA CMD/tip of the red giant branch
ID:
ivo://CDS.VizieR/J/AJ/138/332
Title:
LEDA CMD/tip of the red giant branch
Short Name:
J/AJ/138/332
Date:
21 Oct 2021
Publisher:
CDS
Description:
The color-magnitude diagrams/tip of the red giant branch (CMDs/TRGB) section of the Extragalactic Distance Database contains a compilation of observations of nearby galaxies from the Hubble Space Telescope. Approximately 250 (and increasing) galaxies in the Local Volume have CMDs and the stellar photometry tables used to produce them available through the Web. Various stellar populations that make up a galaxy are visible in the CMDs, but our primary purpose for collecting and analyzing these galaxy images is to measure the TRGB in each. We can estimate the distance to a galaxy by using stars at the TRGB as standard candles. In this paper, we describe the process of constructing the CMDs and make the results available to the public.

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