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- ID:
- ivo://CDS.VizieR/J/MNRAS/365/439
- Title:
- JHK photometry for UKIRT faint galaxies
- Short Name:
- J/MNRAS/365/439
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a multicolour catalogue of faint galaxies situated close to bright stars, V<15, with the aim of identifying high-redshift galaxies suitable for study with adaptive optics-equipped near-infrared imagers and spectrographs. The catalogue is constructed from archival calibration observations of the United Kingdom Infrared Telescope (UKIRT) Faint Standard stars with the UKIRT Fast Track Imager (UFTI) camera on UKIRT. We have analysed the deepest 16 fields from the archive to provide a catalogue of galaxies brighter than K~20.3 lying between 3 and 25-arcsec of the guide stars. We identify 111 objects in a total survey area of 8.7arcmin^2^. Of these, 87 are classified as galaxies based on their light profiles in our ~0.5arcsec median seeing K-band images. 12 of the galaxies have (J-K)>~2.0 consistent with them lying at high redshifts, z>~2. These 12 very red galaxies have K-band magnitudes of K=18.1-20.1 and separations from the guide stars of 4-20arcsec and hence are very well suited to adaptive optics studies to investigate their morphologies and spectral properties on sub-kpc scales. We provide coordinates and JHK photometry for all catalogued objects.
- ID:
- ivo://CDS.VizieR/J/A+A/429/115
- Title:
- JHK' photometry of Blue Compact Dwarf Galaxies
- Short Name:
- J/A+A/429/115
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper is part of a series of publications which present a systematic study of Blue Compact Dwarf (BCD) Galaxies in the near infrared (NIR). Compared to the visible light, NIR data allow a better separation of the starburst emission from the light distribution of the old stellar low-surface brightness (LSB) host galaxy. We analyze deep NIR broad band images of a sample of 11 BCDs, observed with the Calar Alto 3.6m telescope. This work enlarges the samples presented in preceding papers of this study (Noeske et al., 2003A&A...410..481N, Cairos et al., 2003ApJ...593..312C) by BCDs of the most common morphological type, displaying a regular elliptical LSB host galaxy. The data presented here allow the detection and quantitative study of the extended stellar LSB host galaxy in all sample BCDs.
- ID:
- ivo://CDS.VizieR/J/A+A/445/69
- Title:
- JHK' photometry of C stars in NGC 147
- Short Name:
- J/A+A/445/69
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Near-infrared J, H and K' images were used to investigate the stellar contents of the asymptotic giant branch (AGB) population in the nearby dwarf elliptical galaxy NGC 147. The obtained (K,J-K) and (K,H-K) color-magnitude diagrams contain stars of AGB and red giant branch populations, where the former consists of a group of bright blue stars, a dominant population of M giant and a red C star population.We identified 91 AGB C stars in NGC 147 with the mean absolute magnitude and colors of <M_K_>=-7.56, <(J-K)_0_>=1.81 and <(H-K)_0_>=0.74. The estimated number ratio of C stars to M giant stars (C/M) is 0.16+/-0.02. The estimated local C/M ratios of 0.14+/-0.02 for the inner region (r<70") and 0.19+/-0.03 for the outer region (r>70") indicate a weak radial gradient. The mean bolometric magnitude of 91 C stars in NGC 147 is <M_bol_>=-4.32+/-0.49. The bolometric luminosity function of M giant stars in NGC 147 extends up to M_bol_=-5.8 magnitude, and that of only C stars spans -5.6<M_bol_<-3.5. The color histograms of AGB stars in (J-K) and (H-K) show a main peak containing M giant stars, a red tail containing C stars with a weak excess, and a blue excess possibly due to bright blue foreground stars and AGB stars younger than M giants. The comparison of the theoretical isochrone models with the color distribution and the brightness of AGB stars indicates that most of the bright M giants in NGC 147 were formed at log(t_yr_)~8.4 with a range of 8.2~8.6. Ages of the majority of M giant stars in NGC 147 are similar to those of younger M giant stars in its companion NGC 185, while their formation occurred more recently than the older M giant stars in NGC 185 by ~2Gyrs.
- ID:
- ivo://CDS.VizieR/J/A+A/467/1025
- Title:
- JHK photometry of Fornax red giant branch
- Short Name:
- J/A+A/467/1025
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a study of the evolved stellar populations in the dwarf spheroidal galaxy Fornax based on wide-area near-infrared observations, aimed at obtaining new independent estimates of its distance and metallicity distribution. Assessing the reliability of near-infrared methods is most important in view of future space- and ground-based deep near-infrared imaging of resolved stellar systems.
- ID:
- ivo://CDS.VizieR/J/ApJ/491/93
- Title:
- JHK photometry of 9 gamma-ray burst fields
- Short Name:
- J/ApJ/491/93
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Results of a deep, near-infrared survey of a predetermined, consistent sample of gamma-ray burst localizations are presented. This systematic study, conducted from 1994 to 1996, is the first to be designed specifically to examine the extragalactic content of these regions of sky. JHK images of nine of the smallest error boxes from the third Interplanetary Network together with 70arcmin^2^ of control fields were obtained reaching levels up to 200 times fainter than those reached by previous infrared studies of burst locations. Photometric measurements and star/galaxy separation measurements of more than 3000 detected objects were made. An overabundance of brighter galaxies exists in the gamma-ray burst images at the 98% confidence level, which indicates that the bursts are cosmological. Both the level of this enhancement and the galaxy brightness, where it appears, match what is expected for host galaxies. As a group, the brightest galaxy within each error box is slightly brighter than normal but is still consistent with a random population of galaxies. Their positions within the boxes are also consistent with a random distribution, with no preference toward the center. The bright galaxy excess in these regions of sky, combined with a seemingly random population of brightest error box galaxies, suggest that either the true host galaxies are fainter or the error boxes do not point accurately to the hosts.
- ID:
- ivo://CDS.VizieR/J/AJ/148/4
- Title:
- JHK photometry of 913 globular clusters in M31
- Short Name:
- J/AJ/148/4
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present Two Micron All Sky Survey JHK_s_ photometry for 913 star clusters and candidates in the field of M31, which are selected from the latest Revised Bologna Catalog of M31 globular clusters (GCs) and candidates. The photometric measurements in this paper supplement this catalog, and provide the most comprehensive and homogeneous photometric catalog for M31 GCs in the JHK_s_bandpasses. In general, our photometry is consistent with previous measurements. The globular cluster luminosity function (GCLF) peaks for the confirmed GCs derived by fitting a t_5_distribution using the maximum likelihood method are J_0_=15.348_-0.208_^+0.206^, H_0_=14.703_-0.180_^+0.176^, and K_s0_=14.534_-0.146_^+0.142^, all of which agree well with previous studies. The GCLFs are different between metal-rich (MR) and metal-poor (MP), and between inner and outer subpopulations, as MP clusters are fainter than their MR counterparts and the inner clusters are brighter than the outer ones, which confirm previous results. The NIR colors of the GC candidates are on average redder than those of the confirmed GCs, which leads to an obscure bimodal distribution of color indices. The relation of (V-K_s_)_0_ and metallicity shows a notable departure from linearity, with a shallower slope toward the redder end. The color-magnitude diagram (CMD) and color-color diagram show that many GC candidates are located out of the evolutionary tracks, suggesting that some of them may be false M31 GC candidates. The CMD also shows that the initial mass function of M31 GCs covers a large range, and the majority of the clusters have initial masses between 10^3^ and 10^6^M_{sun}_.
- ID:
- ivo://CDS.VizieR/J/A+A/573/A84
- Title:
- JHK photometry of IC 1613 AGB stars
- Short Name:
- J/A+A/573/A84
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A member of the Local Group, IC 1613 is a gas rich irregular dwarf galaxy that appears to have formed stars continuously over the last 10Gyr and is relatively independent of external influences from other galaxies. This paper aims to study the spatial distribution of the asymptotic giant branch (AGB) population in IC 1613 and its metallicity.
- ID:
- ivo://CDS.VizieR/J/MNRAS/404/1475
- Title:
- JHK photometry of Leo I AGB and red giants
- Short Name:
- J/MNRAS/404/1475
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A near-infrared imaging study of the evolved stellar populations in the dwarf spheroidal galaxy Leo I is presented. Based on JHK observations obtained with the WFCAM wide-field array at the United Kingdom Infrared Telescope, we build a near-infrared photometric catalogue of red giant branch (RGB) and asymptotic giant branch (AGB) stars in Leo I over a 13.5arcmin^2^ area. The V-K colours of RGB stars, obtained by combining the new data with existing optical observations, allow us to derive a distribution of global metallicity [M/H] with average [M/H]=-1.51 (uncorrected) or [M/H]=-1.24+/-.05(int)+/-0.15(syst) after correction for the mean age of Leo I stars.
- ID:
- ivo://CDS.VizieR/J/ApJS/118/177
- Title:
- JHK photometry of M31 spiral arm
- Short Name:
- J/ApJS/118/177
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Deep high-resolution JHK images of a 2'x2' field around the OB association A24 near the 7kpc spiral arm in M31 were measured to yield photometric data of more than 3000 stars with the faintest magnitude being J=21.3, H=20.5, and K=19.6. The photometric data for the 1037 stars that are brightest in the K band are presented. Judging from the color-magnitude and the two-color diagrams, we find that the majority of the observed stars are AGB stars including large-amplitude variables. They are distributed smoothly over the observed field, and we find no clear evidence of varying extinction over the field for these red stars. The present sample includes bright AGB stars of M_K_<=-8 and about 30 young blue objects of (J-H)<0.75 that are brighter than M_J_~=-6.5.
