- ID:
- ivo://CDS.VizieR/J/AJ/138/1667
- Title:
- HST survey of young clusters in M31. III.
- Short Name:
- J/AJ/138/1667
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Surface brightness profiles for 23 M31 star clusters were measured using images from the Wide Field Planetary Camera 2 on the Hubble Space Telescope, and fitted to two types of models to determine the clusters' structural properties. The clusters are primarily young (~108yr) and massive (~104.5M_{sun}_), with median half-light radius 7pc and dissolution times of a few Gyr. The properties of the M31 clusters are comparable to those of clusters of similar age in the Magellanic Clouds. Simulated star clusters are used to derive a conversion from statistical measures of cluster size to half-light radius so that the extragalactic clusters can be compared to young massive clusters in the Milky Way. All three sets of star clusters fall approximately on the same age-size relation. The young M31 clusters are expected to dissolve within a few Gyr and will not survive to become old, globular clusters. However, they do appear to follow the same fundamental plane (FP) relations as old clusters; if confirmed with velocity dispersion measurements, this would be a strong indication that the star cluster FP reflects universal cluster formation conditions.
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- ID:
- ivo://CDS.VizieR/J/A+AS/129/583
- Title:
- Hubble Deep Field surface photometry
- Short Name:
- J/A+AS/129/583
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The detailed surface photometry of a sample of early-type galaxies in the Hubble Deep Field is presented as part of a long-term project aimed to settle strong observational constraints to the theories modelling the evolution of elliptical galaxies from the early stages. The sample has been extracted, in the V_606_ band, from the database provided by the ESO-STECF-HDF Group (Couch, 1996, <http://ecf.hq.eso.org>). The selection criteria involve the total magnitude, the number of pixels detected above the background level and an automatic star/galaxy classifier. Moreover, form visual inspection of the frames, we excluded the galaxies showing unambiguous late-type morphology. The analysis of the luminosity and geometrical profiles, carried out on the 162 candidates obeying our selection criteria, resulted in a list of 99 'bona fide' early-type galaxies, for which accurate total magnitudes and effective radii were computed on the basis of the equivalent luminosity profiles. The comparison with the magnitudes given by Williams et al. (1996, Cat. <J/AJ/112/1335>) indicates that the automated photometry tends to underestimate the total luminosity of the ellipticals. The luminosity profiles of most of galaxies in our sample follow fairly well the de~Vaucouleurs law ('Normal' profiles). However, a relevant fraction of galaxies, even following the r^1/4^ law in the main body light distribution, exhibit in the inner region a flattening of the luminosity profile not attributable to the PSF (`Flat' profiles) or, in some cases, a complex (multi-nucleus) structure (`Merger' profiles). A statistically significant correlation is found between the shapes of the luminosity profiles and the ellipticity distribution. In particular, the average ellipticity of galaxies belonging to the `Flat' and `Merger' classes is significantly higher than that of the `Normal' galaxies. Finally, even taken into account the relevant uncertainty of the outer position angle profiles, the amount of isophotal twisting of HDF ellipticals turns out to be significantly larger with respect to that of the local samples.
- ID:
- ivo://CDS.VizieR/J/AJ/127/704
- Title:
- Low surface brightness galaxies in SDSS
- Short Name:
- J/AJ/127/704
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this paper we present results of a pilot study to use imaging data from the Sloan Digital Sky Survey (SDSS) to search for low surface brightness (LSB) galaxies. For our pilot study we use a test sample of 92 galaxies from the Impey et al. catalog distributed over 93 SDSS fields of the Early Data Release (EDR, <J/AJ/123/567>). Many galaxies from the test sample are either LSB or dwarf galaxies. To deal with the SDSS data most effectively, a new photometry software was created, which is described in this paper. We present the results of the selection algorithms applied to these 93 EDR fields. Two galaxies from the Impey et al. (1996, <J/ApJS/105/209>) test sample are very likely artifacts, as confirmed by follow-up imaging. With our algorithms we were able to recover 87 of the 90 remaining test sample galaxies, implying a detection rate of ~96.5%. The three missed galaxies fall too close to very bright stars or galaxies. In addition, 42 new galaxies with parameters similar to the test sample objects were found in these EDR fields (i.e.,~47% additional galaxies). We present the main photometric parameters of all identified galaxies and carry out first statistical comparisons. We tested the quality of our photometry by comparing the magnitudes for our test sample galaxies and other bright galaxies with values from the literature. All these tests yielded consistent results. We briefly discuss a few unusual galaxies found in our pilot study, including an LSB galaxy with a two-component disk and 10 new giant LSB galaxies.
- ID:
- ivo://CDS.VizieR/J/A+A/458/341
- Title:
- LSBG in Arecibo HI Strip Survey
- Short Name:
- J/A+A/458/341
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In order to estimate the contribution of low surface brightness (LSB) galaxies to the local (z<=0.1) galaxy number density, we performed an optical search for LSB candidates in a 15.5{deg}^2^ part of the region covered by the 65{deg}^2^ blind Arecibo HI Strip Survey (AHISS)
- ID:
- ivo://CDS.VizieR/J/MNRAS/240/785
- Title:
- Multicolour photometry of Sersic 129-01
- Short Name:
- J/MNRAS/240/785
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- (no description available)
- ID:
- ivo://CDS.VizieR/J/other/RAA/11.309
- Title:
- Nearby early-type galaxies in Stripe 82
- Short Name:
- J/other/RAA/11.3
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We make use of the images from the Sloan Digital Sky Survey Stripe 82 (Stripe 82) to present an analysis of r band surface brightness profiles and radial color gradients (g-r, u-r) in our sample of 111 nearby early-type galaxies (ETGs). Thanks to the Stripe 82 images, each of which is co-added from about 50 single frames, we are able to pay special attention to the low-surface-brightness areas (LSB areas) of the galaxies.
- ID:
- ivo://CDS.VizieR/J/A+AS/121/507
- Title:
- Near-IR surface photometry of Virgo galaxies
- Short Name:
- J/A+AS/121/507
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The basic parameters of galaxies observed in this work: table 3: total H and K' magnitudes derived using circular apertures; table 5: photometric parameters derived along elliptical apertures
- ID:
- ivo://CDS.VizieR/J/A+A/654/A40
- Title:
- NGC1042 g and r deep final images
- Short Name:
- J/A+A/654/A40
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- We present the first results of the LBT Imaging of Galaxy Haloes and Tidal Structures (LIGHTS) survey. LIGHTS is an ongoing observational campaign with the 2x8.4m Large Binocular Telescope (LBT) aiming to explore the stellar haloes and the low surface brightness population of satellites down to a depth of mu_V_~31mag/arcsec^2^ (3s in 10"x10" boxes) of nearby galaxies. We simultaneously collected deep imaging in the g and r Sloan filters using the Large Binocular Cameras (LBCs). The resulting images are 60 times (i.e. 4.5mag) deeper than those from the Sloan Digital Sky Survey (SDSS), and they have characteristics comparable (in depth and spatial resolution) to the ones expected from the future Legacy Survey of Space and Time (LSST). Here we show the first results of our pilot programme targeting NGC1042 (an M33 analogue at a distance of 13.5Mpc) and its surroundings. The depth of the images allowed us to detect an asymmetric stellar halo in the outskirts of this galaxy whose mass (1.4+/-0.4x10^8^M_{sun}_) is in agreement with the Lambda Cold Dark Matter (LambdaCDM) expectations. Additionally, we show that deep imaging from the LBT reveals low mass satellites (a few times 10^5^M_{sun}_) with very faint central surface brightness mu_V(0)_~27mag/arcsec^2^(i.e. similar to Local Group dwarf spheroidals, such as Andromeda XIV or Sextans, but at distances well beyond the local volume). The depth and spatial resolution provided by the LIGHTS survey open up a unique opportunity to explore the `missing satellites' problem in a large variety of galaxies beyond our Local Group down to masses where the difference between the theory and observation (if any) should be significant.
- ID:
- ivo://CDS.VizieR/J/ApJ/833/167
- Title:
- PAndAS view of Andromeda satellites. II.
- Short Name:
- J/ApJ/833/167
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a comprehensive analysis of the structural properties and luminosities of the 23 dwarf spheroidal galaxies that fall within the footprint of the Pan-Andromeda Archaeological Survey (PAndAS). These dwarf galaxies represent the large majority of Andromeda's known satellite dwarf galaxies and cover a wide range in luminosity (-11.6<~M_V_<~-5.8 or 10^4.2^<~L<~10^6.5^L_{sun}_) and surface brightness (25.1<~{mu}_0_<~29.3mag/arcsec^2^). We confirm most previous measurements, but we find And XIX to be significantly larger than before (r_h_=3065_-935_^+1065^pc, M_V_=-10.1_-0.4_^+0.8^) and cannot derive parameters for And XXVII as it is likely not a bound stellar system. We also significantly revise downward the luminosities of And XV and And XVI, which are now M_V_~-7.5 or L~10^5^L_{sun}_. Finally, we provide the first detailed analysis of Cas II/And XXX, a fairly faint system (M_V_=-8.0_-0.3_^+0.4^) of typical size (r_h_=270+/-50pc), located in close proximity to the two bright elliptical dwarf galaxies NGC 147 and NGC 185. Combined with the set of homogeneous distances published in an earlier contribution, our analysis dutifully tracks all relevant sources of uncertainty in the determination of the properties of the dwarf galaxies from the PAndAS photometric catalog. We further publish the posterior probability distribution functions of all the parameters we fit for in the form of MCMC chains available online; these inputs should be used in any analysis that aims to remain truthful to the data and properly account for covariance between parameters.
- ID:
- ivo://CDS.VizieR/J/A+AS/118/7
- Title:
- Photometry & morphology of UCM galaxies
- Short Name:
- J/A+AS/118/7
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of Thuan & Gunn r CCD imaging observations of the Universidad Complutense de Madrid (UCM) sample of emission-line galaxies (ELGs), selected by the presence of H{alpha} emission in low-resolution objective prism spectra. In this work we characterize photometrically and morphologically a total of 212 objects from the UCM survey. This Paper presents the observations and basic reductions, and lists a set of photometric parameters calculated for each UCM object. In addition, for the first time in a ELGs sample, we have determined the morphological classification of the objects using simultaneously five different criteria.
