- ID:
- ivo://CDS.VizieR/J/MNRAS/426/1475
- Title:
- CaT in 903 globular clusters
- Short Name:
- J/MNRAS/426/1475
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Although the colour distribution of globular clusters in massive galaxies is well known to be bimodal, the spectroscopic metallicity distribution has been measured in only a few galaxies. After redefining the calcium triplet index-metallicity relation, we use our relation to derive the metallicity of 903 globular clusters in 11 early-type galaxies. This is the largest sample of spectroscopic globular cluster metallicities yet assembled. We compare these metallicities with those derived from Lick indices finding good agreement. In six of the eight galaxies with sufficient numbers of high-quality spectra we find bimodality in the spectroscopic metallicity distribution. Our results imply that most massive early-type galaxies have bimodal metallicity as well as colour distributions. This bimodality suggests that most massive early-type galaxies experienced two periods of star formation.
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Search Results
- ID:
- ivo://CDS.VizieR/J/A+A/285/785
- Title:
- 3C 295 BRri photometry
- Short Name:
- J/A+A/285/785
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We observed the cluster Cl 1409+524 (z=0.46) with an imaging Fabry-Perot interferometer. A sequence of Fabry-Perot images (FWHM=1.0-1.3nm) was used to search for redshifted [OII]{lambda}372.7nm- and [OIII]{lambda}500.7nm line emission. We studied 144 galaxies up to a limiting continuum R-band magnitude of 22.5mag within 1 Mpc around the cluster center. Previously known emission-line galaxies in the cluster were confirmed and 17 new members with emission lines were found. Their star formation rate of 1-2M_{sun}_/yr is typical for normal spirals. We have imaged the cluster with broad band B, R and seven intermediate band filters (FWHM=10.0-20.0nm) in order to derive low-resolution spectral energy distributions of cluster galaxies. These were fitted by template spectra to estimate Hubble class and redshifts. Based on this decomposition, we derived a percentage of emission-line galaxies of 40+/-11%.
- ID:
- ivo://CDS.VizieR/J/A+A/644/A107
- Title:
- 3C 129 candidate cluster galaxies
- Short Name:
- J/A+A/644/A107
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalogue of 261 new infrared selected members of the 3C 129 galaxy cluster. The cluster, located at z=0.02, forms part of the Perseus-Pisces filament and is obscured at optical wavelengths due to its location in the zone of avoidance. We identified these galaxies using the J- and K-band imaging data provided by the UKIDSS Galactic Plane Survey within an area with a radius of 1.1{deg} centred on the X-ray emission of the cluster at (l, b) = (160.52{deg}, 0.27{deg}). A total of 26 of the identified galaxy members have known redshifts 24 of which are from our 2016 Westerbork HI survey and two are from optical spectroscopy. An analysis of the galaxy density at the core of the 3C 129 cluster shows it to be less dense than the Coma and Norma clusters, but comparable to the galaxy density in the core of the Perseus cluster. From an assessment of the spatial and velocity distributions of the 3C 129 cluster galaxies that have redshifts, we derived a velocity of cz=5227+/-171km/s and=1097+/-252km/s for the main cluster, with a substructure in the cluster outskirts at cz=6923+/-71km/s with {sigma}=422+/-100km/s. The presence of this substructure is consistent with previous claims based on the X-ray analysis that the cluster is not yet virialised and may have undergone a recent merger.
- ID:
- ivo://CDS.VizieR/J/A+A/620/A137
- Title:
- CCD B,V,R,I,Ha photometry of 3C120
- Short Name:
- J/A+A/620/A137
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- At the Universitaetssternwarte Bochum near Cerro Armazones we have monitored the Seyfert-1 galaxy 3C 120 between September 2014 and March 2015 in BVRI and a narrow band filter covering the redshifted H{alpha} line; in addition we obtained a single con-temporary spectrum with FAST at Mt. Hopkins. Compared to earlier epochs 3C 120 is about a factor of three brighter, allowing us to study the shape of the broad line region (BLR) and the dust torus in a high luminosity phase. The analysis of the light curves yields that the dust echo is rather sharp and symmetric in contrast to the more complex broad H{alpha} BLR echo. We investigate how far this supports an optically thick bowl-shaped BLR and dust torus geometry as proposed by Kawaguchi & Mori (2010ApJ...724L.183K) and Goad et al. (2012MNRAS.426.3086G). The comparison with several parameterizations of these models supports the following geometry: the BLR clouds lie inside the bowl closely above the bowl rim, up to a half covering angle 0{deg}<theta<40{deg} (measured against the equatorial plane). Then the BLR is spread over many isodelay surfaces, yielding a smeared and structured echo as observed. Furthermore, if the BLR clouds shield the bottom of the bowl rim against radiation from the nucleus, the hot dust emission comes essentially from the top edge of the bowl (40{deg}<theta< 45{deg}). Then, for small inclinations as for 3C120, the top dust edge forms a ring which largely coincides with a narrow range of isodelay surfaces, yielding the observed sharp dust echo. The scale height of the BLR increases with radial distance from the black hole. This leads to luminosity dependent foreshortening effects of the lag. We discuss implications and possible corrections of the foreshortening for the black hole mass determination and consequences for the lag (size) - luminosity relationships and the difference to interferometric torus sizes.
- ID:
- ivo://CDS.VizieR/J/A+A/414/23
- Title:
- CCD H{alpha} and R photometry of 334 galaxies
- Short Name:
- J/A+A/414/23
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We discuss the selection and observations of a large sample of nearby galaxies, which we are using to quantify the star formation activity in the local Universe. The sample consists of 334 galaxies across all Hubble types from S0/a to Im and with recession velocities of between 0 and 3000km/s. The basic data for each galaxy are narrow band H{alpha}+[NII] and R-band imaging, from which we derive star formation rates, H{alpha}+[NII] equivalent widths and surface brightnesses, and R-band total magnitudes. A strong correlation is found between total star formation rate and Hubble type, with the strongest star formation in isolated galaxies occurring in Sc and Sbc types. More surprisingly, no significant trend is found between H{alpha}+[NII] equivalent width and galaxy R-band luminosity. More detailed analyses of the data set presented here will be described in subsequent papers.
- ID:
- ivo://CDS.VizieR/J/MNRAS/246/433
- Title:
- CCD photometry & APM parameters for galaxies
- Short Name:
- J/MNRAS/246/433
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The sequences for UKS fields 152 246 and 249 appear to be discrepant with the plate matching in the APM survey, and so may not be completely reliable.
- ID:
- ivo://CDS.VizieR/J/A+AS/111/527
- Title:
- CCD photometry of 11 dwarf irregular galaxies
- Short Name:
- J/A+AS/111/527
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present CCD imaging and photometry in B and Cousins R of the dwarf irregular galaxies UGC 4459 (=DDO 53), UGC 5272 (A=DDO 64 and B), UGC 5340 (=DDO 68), UGC 6456, UGC 7559 (=DDO 126), UGC 8024 (=NGC 4789A=DDO 154), UGC 8091 (= GR 8=DDO 155), UGC 8320 (=DDO 168), UGC 8760 (=DDO 183), and DDO 210. For DDO 210 we also give results in the V filter. Photometry of the resolved stars was carried out on background-subtracted images using DAOPHOT. The tables of measurements include positions, magnitudes, colors, a magnitude error, and a color error. Integrated fluxes and colors are also reported. The single-star photometry is compared to previous results in three of the galaxies (UGC 8024, UGC 8091, DDO 210).
- ID:
- ivo://CDS.VizieR/J/AJ/129/729
- Title:
- CCD photometry of luminous stars in M33
- Short Name:
- J/AJ/129/729
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The M33 galaxy is a nearby, relatively metal-poor, late-type spiral. Its proximity and almost face-on inclination means that it projects over a large area on the sky, making it an ideal candidate for wide-field CCD mosaic imaging. Photometry was obtained for more than 106 stars covering a 74'x56' field centered on M33. Main-sequence, supergiant branch, red giant branch, and asymptotic giant branch (AGB) populations are identified and classified based on broadband V and I photometry. Narrowband filters are used to measure spectral features allowing, the AGB population to be further divided into C and M star types. The galactic structure of M33 is examined using star counts, color-color, and color-magnitude-selected stellar populations. We use the C to M star ratio to investigate the metallicity gradient in the disk of M33.
- ID:
- ivo://CDS.VizieR/J/ApJ/682/135
- Title:
- CCD photometry of M60
- Short Name:
- J/ApJ/682/135
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a photometric study of the globular clusters (GCs) in the giant elliptical galaxy M60 in the Virgo Cluster, based on deep, relatively wide field Washington CT_1_ CCD images. The CMD reveals a significant population of GCs in M60 and a large number of young luminous clusters in NGC 4647, a small companion spiral northwest of M60. The color distribution of the GCs in M60 is clearly bimodal, with a blue peak at (C-T_1_)=1.37 and a red peak at (C-T_1_)=1.87. We derive two new transformation relations between the (C-T_1_)_0_ color and [Fe/H] using the data for the GCs in our Galaxy and M49. Using these relations, we derive the metallicity distribution of the GCs in M60, which is also bimodal: a dominant metal-poor component with center at [Fe/H]=-1.2, and a weaker metal-rich component with center at [Fe/H]=-0.2. We estimate the total number of the GCs in M60 to be 3600+/-500 and the specific frequency to be S_N_=3.8+/-0.4.
- ID:
- ivo://CDS.VizieR/J/A+A/382/389
- Title:
- CCD R photometry of 17 clusters of galaxies
- Short Name:
- J/A+A/382/389
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a study of streaming motion of galaxy clusters around the Giant Void (RA~13h, DE~40{deg}, z~0.11 and a diameter of 150/hMpc) in the distribution of rich Abell clusters. We used the Kormendy relation as a distance indicator taking into account galaxy luminosities. Observations were carried out in Kron-Cousins R_c_ system on the 6m and 1m telescopes of SAO RAS. For 17 clusters in a spherical shell of 25/hMpc in thickness centered on the void no significant diverging motion (expected to be generated by the mass deficit in the void) has been detected. This implies that cosmological models with low {Omega}_m_ are preferred. To explain small mass underdensity inside the Giant Void, a mechanism of void formation with strong biasing is required.
