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2431. Near-infrared survey around PKS 1343-601
ID:
ivo://CDS.VizieR/J/A+A/466/481
Title:
Near-infrared survey around PKS 1343-601
Short Name:
J/A+A/466/481
Date:
21 Oct 2021
Publisher:
CDS
Description:
The highly obscured radio-bright galaxy PKS 1343-601 at Galactic coordinates of (l,b)=(309.7,+1.8) has been suspected to mark the centre of a hitherto unknown cluster in the wider Great Attractor region. As such it presents an ideal region for a search of galaxies in the near-infrared (NIR) and an in-depth study of their colours as a function of extinction. A visual search of a ~30 square-degree area centred on this radio galaxy on images of the NIR DENIS survey (IJK) revealed 83 galaxies (including two AGNs) and 39 possible candidates. Of these, 49 are also listed in the 2MASS Extended Source Catalog 2MASX. Taking the IRAS/DIRBE extinction values (Schlegel et al., 1998ApJ...500..525S) at face value, the absorption in the optical (AB) ranges from ~2mag to over 100mag across the Galactic Plane. Comparing the detections with other systematic surveys, we conclude that this search is highly complete up to the detection limits of the DENIS survey and certainly surpasses any automatic galaxy finding algorithm applied to crowded areas.
2432. Near-infrared survey around PKS 1343-601
ID:
ivo://CDS.VizieR/J/MNRAS/354/980
Title:
Near-infrared survey around PKS 1343-601
Short Name:
J/MNRAS/354/980
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of a deep near-infrared survey of a 36x36arcmin^2^ region centred on the giant elliptical radio galaxy PKS 1343-601, suggested to be the core of an unknown rich cluster located at the low Galactic latitude of b=1.73{deg} in the Great Attractor (GA) region. 19 obvious galaxies and 38 galaxy candidates have been detected; only three of them were previously identified as a galaxy.
2433. Near IR Imaging of Early-Type Galaxies
ID:
ivo://CDS.VizieR/J/ApJS/124/127
Title:
Near IR Imaging of Early-Type Galaxies
Short Name:
J/ApJS/124/127
Date:
21 Oct 2021
Publisher:
CDS
Description:
An imaging survey of 341 nearby early-type galaxies in the near-infrared K-band atmospheric window (2.2{micron}) is described. The galaxies primarily reside in 13 nearby rich clusters (85%), while some additional galaxies are drawn from loose groups (12%) and the general field (3%). Surface photometry was measured for the entire sample. Detailed corrections were derived from an extensive grid of seeing-convolved r^1/4^ models and then applied to the isophotal surface brightness, aperture magnitude, and ellipticity profiles. Global photometric parameters were derived from this seeing-corrected photometry. More than 25% of the sample has been observed at least twice, and these repeat measurements demonstrate the small internal uncertainties on the derived global photometric parameters. Extensive comparisons with aperture photometry from the literature demonstrate that the photometric system is fully consistent with other photometric systems to <=0.01mag and confirm the estimates of internal random uncertainties. Additional global parameters are drawn from the literature in a homogeneous manner in order to construct a large catalog of galaxy properties: 95% of the galaxies have a velocity dispersion, 69% have a Mg_2_ index, 80% have an optical r_eff_ and {mu}_eff_, 82% have a D_n_, and 81% have a derived optical - infrared color measurement. This large data set provides excellent source material for investigations of the physical origins of the global scaling relations of early-type galaxies, velocity fields in the local universe, and comparisons to higher redshift early-type galaxies.
2434. Near-IR observations of XMM-LSS J02182-05102
ID:
ivo://CDS.VizieR/J/ApJ/750/93
Title:
Near-IR observations of XMM-LSS J02182-05102
Short Name:
J/ApJ/750/93
Date:
21 Oct 2021
Publisher:
CDS
Description:
We discuss the structural and morphological properties of galaxies in a z=1.62 proto-cluster using near-IR imaging data from Hubble Space Telescope Wide Field Camera 3 data of the Cosmic Assembly Near-IR Deep Extragalactic Legacy Survey (CANDELS). The cluster galaxies exhibit a clear color-morphology relation: galaxies with colors of quiescent stellar populations generally have morphologies consistent with spheroids, and galaxies with colors consistent with ongoing star formation have disk-like and irregular morphologies. The size distribution of the quiescent cluster galaxies shows a deficit of compact (<~1kpc), massive galaxies compared to CANDELS field galaxies at z=1.6. As a result, the cluster quiescent galaxies have larger average effective sizes compared to field galaxies at fixed mass at greater than 90% significance. Combined with data from the literature, the size evolution of quiescent cluster galaxies is relatively slow from z=~1.6 to the present, growing as (1+z)^-0.6+/-0.1^. If this result is generalizable, then it implies that physical processes associated with the denser cluster region seem to have caused accelerated size growth in quiescent galaxies prior to z=1.6 and slower subsequent growth at z<1.6 compared to galaxies in the lower density field. The quiescent cluster galaxies at z=1.6 have higher ellipticities compared to lower redshift samples at fixed mass, and their surface-brightness profiles suggest that they contain extended stellar disks. We argue that the cluster galaxies require dissipationless (i.e., gas-poor or "dry") mergers to reorganize the disk material and to match the relations for ellipticity, stellar mass, size, and color of early-type galaxies in z<1 clusters.
2435. Near-IR photometry of AGB stars in IC 1613
ID:
ivo://CDS.VizieR/J/A+A/578/A51
Title:
Near-IR photometry of AGB stars in IC 1613
Short Name:
J/A+A/578/A51
Date:
21 Oct 2021
Publisher:
CDS
Description:
We investigated the photometric properties of asymptotic giant branch (AGB) stars of dwarf irregular galaxy IC 1613 and its metallicity. We used near-infrared JHKs photometric data obtained with the WIRCam array on Canada-France-Hawaii Telescope (CHFT). The optical gi imaging data of previous study were cross-matched with ours to distinguish the stellar populations in the galaxy and to select the AGB stars. We also separated the C stars from the M-giant stars in the JHKs color-color diagram. We identified 140 C stars and 306 M-giant stars in IC 1613. The (J-Ks) color histogram of AGB stars shows the main peak of M-giant stars and the red tail of C stars. The broad color distribution of M-giant stars and the isochrones in color magnitude diagram indicate that IC 1613 has a wide range of intermediate-age stars. We also know that most C stars were formed over the past 2-8Gyr according the M_bol-age relation. The C/M ratio of 0.46+/-0.05 was estimated and [Fe/H] abundance of -1.23+/-0.06 was derived from the C/M ratio. Radial distributions of C/M ratio and metallicity show the shallow trend of the negative metallicity gradient from the center. The local C/M ratio also indicates that the HI cavity has higher C/M values than the bright HI spot and HI gas region. However, the low [Fe/H] value near the central region of the galaxy is likely to be caused by the change in age of the dominant stellar population according to the radial distance, not the real metallicity variation. It might also be that relatively younger and metal-rich C stars are concentrated in the center of the galaxy, while the M-giant stars were homogeneously distributed from the center to the borders of the galaxy.
2436. Near-IR photometry of C and AGB stars in NGC 6822
ID:
ivo://CDS.VizieR/J/A+A/454/717
Title:
Near-IR photometry of C and AGB stars in NGC 6822
Short Name:
J/A+A/454/717
Date:
21 Oct 2021
Publisher:
CDS
Description:
Images of JHK and gi obtained with the Canada-France-Hawaii Telescope are used to investigate the stellar contents of the resolved asymptotic giant branch (AGB) population in the area of 3.6'x6.3' on the central bar of the dwarf irregular galaxy NGC 6822. The upper envelope of near-infrared (J-K, K) and (H-K, K) color-magnitude diagrams (CMDs) shows four components of main-sequence stars, foreground stars, massive supergiants, and AGB stars. These components are also noticeable in the bright part of (g-i, g) CMD. We select AGB stars in NGC 6822 from the (g-K, g) CMD, which has a long spectral wavelength base line in the color index. There are 141 C stars with a mean absolute magnitude of <M_K_>=-7.60+/-0.50, and with mean colors of <(J-K)_o_>=1.77+/-0.41, and <(H-K)_o_>=0.75+/-0.28. The number ratio of C stars to M-giants (C/M) is estimated as 0.27+/-0.03, while the northern part of the bar has a somewhat lower C/M ratio than the southern part. The (J-K) and (H-K) color distributions of AGB stars contain a main peak of M-giant stars and a red tail of C stars. The broad color distributions for M-giants indicate that NGC 6822 has a wide range of intermediate ages with a peak at log(t_yr_)~9.0. The M_K_ luminosity function (LF) for C stars in the central bar of NGC 6822 is likely to be a Gaussian distribution, while the LF of C stars in the southern part is slightly skewed to the brighter side than in northern part. The mean bolometric magnitude of 141 C stars in NGC 6822 is <M_bol_>=-4.36+/-0.54. The bolometric LF for M-giants extends up to M_bol_=-6.5, while the one for C stars spans -5.8<M_bol_<-3.5.
2437. Near-IR photometry of C stars in NGC 205
ID:
ivo://CDS.VizieR/J/A+A/543/A35
Title:
Near-IR photometry of C stars in NGC 205
Short Name:
J/A+A/543/A35
Date:
21 Oct 2021
Publisher:
CDS
Description:
We investigated the distribution of resolved asymptotic giant branch (AGB) stars over a much larger area than covered by previous near-infrared studies in the nearby dwarf elliptical galaxy NGC 205. Using data obtained with the WIRCam near-infrared imager of the CFHT, we selected the AGB stars in the JHKs color - magnitude diagrams, and separated the C stars from M-giant stars in the JHKs color - color diagram. We identified 1,550 C stars in NGC 205 with a mean absolute magnitude of <M_Ks>=-7.49+/-0.54, and colors of <(J-K)_0>=1.81+/-0.41 and <(H-Ks)_0>=0.76+/-0.24. The ratio of C stars to M-giant stars was estimated to be 0.15+/-0.01 in NGC 205, and the local C/M ratios for the southern region are somewhat lower than those for the northern region. The (J-K) color distributions of AGB stars contain the main peak of the M-giant stars and the red tail of the C stars. A comparison of the theoretical isochrone models with the observed color distribution indicates that most of the bright M-giant stars in NGC 205 were formed at log(t_yr_)~9.0-9.7. The logarithmic slope of the M_Ks_ luminosity function for M-giant stars was estimated to be 0.84+/-0.01, which is comparable with dwarf elliptical galaxies NGC 147 and NGC 185. Furthermore, we found that the logarithmic slopes of the M_Ks_ luminosity function for C and M-giant stars are different to places, implying a different star formation history within NGC 205. The bolometric luminosity function for M-giant stars extends to M_bol_=-6.0mag, and that for C stars spans -5.6<M_bol_<-3.0. The bolometric luminosity function of C stars is unlikely to be a Gaussian distribution and the mean bolometric magnitude of C stars is estimated to be M_bol_=-4.24+/-0.55, which is consistent with our results for dwarf elliptical galaxies NGC 147 and NGC 185.
2438. Near-IR photometry of 86 galaxies. II.
ID:
ivo://CDS.VizieR/J/A+AS/118/557
Title:
Near-IR photometry of 86 galaxies. II.
Short Name:
J/A+AS/118/557
Date:
21 Oct 2021
Publisher:
CDS
Description:
In this Paper I present a new two-dimensional decomposition technique, which models the surface photometry of a galaxy with an exponential light profile for both bulge and disk and, when necessary, with a Freeman bar. The new technique w as tested for systematic errors on both artificial and real data and compared with widely used one-dimensional decomposition techniques, where the luminosity profile of the galaxy is used. The comparisons indicate that a decomposition of the two-dimensional image of the galaxy with an exponential light profile for both bulge and disk yields the most reproducible and representative bulge and disk parameters. An extensive error analysis was made to determine the reliability of the model parameters. If the model with an exponential bulge profile is a reasonable description of a galaxy, the maximum errors in the derived model parameters are of order 20%. The uncertainties in the model parameters will increase, if the exponential bulge function is replaced by other often used bulge functions as the de Vaucouleurs law. All decomposition methods were applied to the optical and near-infrared data set presented by de Jong & van der Kruit (1994), which comprises 86 galaxies in six passbands.
2439. Near IR properties of Galaxy disks
ID:
ivo://CDS.VizieR/J/ApJ/510/637
Title:
Near IR properties of Galaxy disks
Short Name:
J/ApJ/510/637
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have derived the near-infrared structural components of a sample of Seyfert and starburst (SBN) host galaxies by fitting near-infrared images with a new two-dimensional decomposition algorithm. An analysis of the fitted parameters shows that Seyfert 1 and SBN bulges resemble normal early-type bulges in structure and color, with (J-K)^c^_b_ about 0.1 mag redder than disk (J-K)^c^_d_. Seyfert 2 bulges, on the other hand, are bluer than normal, with (J-K)^c^_b_{approx}(J-K)^c^_d_. Seyfert disks (especially type 1), but not those of SBNs, are abnormally bright (in surface brightness), significantly more so than even the brightest normal disks. Seyfert disks are also compact, but similar to those in normal early-type spirals. For a given mass, Seyfert and particularly SBN galaxies are abnormally rich in neutral hydrogen, and there is strong, albeit indirect, evidence for lower mass-to-light (M/L) ratios in Seyfert and SBN disks, but normal M/L ratios in their bulges. In Seyfert and SBN galaxies, H I mass fractions and M/L ratios are anticorrelated, and we attribute the high gas mass fractions and low M/L ratios in SBNs and several Seyfert galaxies to ongoing star formation. Such abundant gas in Seyfert galaxies would be expected to inhibit bar formation, which may explain why active galaxies are not always barred.
2440. Near-IR surface photometry of Virgo 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