- ID:
- ivo://CDS.VizieR/J/AJ/110/2844
- Title:
- JHK photometry of globular clusters. III.
- Short Name:
- J/AJ/110/2844
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new JHK photometry for the disk globular clusters NGC 6440 and NGC 6624. These data are initially used to confirm and refine several important results from Kuchinski et al. (1995AJ....109.1131K) for other disk globular. First, we again demonstrate the ability to derive a reddening-independent estimate for the [Fe/H] of a cluster from the slope if its giant branch (GB) in a K, J-K color magnitude diagram (CMD). Second, the reddening corrected J-K color and K magnitude of the center of the horizontal branch (HB) and the J-K color of its red edge are confirmed to be independent of [Fe/H] for these clusters. Thus these parameters can be used to estimate E(J-K) of metal-rich clusters with no knowledge of distance or [Fe/H] and to estimate (m-M) if one can first estimate the reddening. We also confirm that the reddening-independent quantities, the half width of a cluster's horizontal branch (HB), and the color difference between the center of the HB and the GB at the level of the HB, both appear to be insensitive to metallicity. The JHK colors of NGC 6440 are similar to those of Liller 1; in both cases these colors are unlike those seen for other globular clusters, field giants, or bulge giants. We have not been able to identify any other cluster parameter that would help to explain these anomalous colors. We have assembled V photometry from the literature for the clusters in our sample and VK photometry for two additional disk globular clusters from Davidge et al. (1992ApJS...81..251D). We conclude that K, J-K CMDs are preferable to K, V-K CMDs as tools to study basic cluster properties. Finally, we compare our data with theoretical isochrones for metal-rich clusters and present observational evidence that the dependence of the V-K color of the GB on [Fe/H] may be different for halo and disk globular clusters. This difference may be related to differences in the [O/Fe] values for the two cluster systems.
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- 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/AJ/109/1154
- Title:
- JHK Photometry of Liller 1
- Short Name:
- J/AJ/109/1154
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first color-magnitude diagram of Liller 1, a globular cluster with an angular separation of only 5 deg from the galactic center and a latitude of 0.2 deg. We estimate a metallicity for this cluster of [Fe/H] = +0.25 +/- 0.3 based on the slope of Liller 1's giant branch in the near-infrared. This implies that Liller 1 is the most metal rich galactic globular cluster known. Any reasonable uncertainty in the age of the cluster will not affect our method for deriving the metallicity. We also conclude that for Liller 1 E(J-K) = 1.70 +/- 0.06 (or A_V ~ 9.5) and (m-M)0 = 14.68 +/- 0.23. The atypical JHK colors of the Liller 1 stars, the extreme slope of its giant branch, and its physical closeness to the galactic center raise the question of whether it is a normal globular cluster or if its formation and evolution have been strongly influenced by its proximity to the galactic center.
- ID:
- ivo://CDS.VizieR/J/PASJ/58/L29
- Title:
- JHK photometry of low-mass stars in BRC 14
- Short Name:
- J/PASJ/58/L29
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We carried out a deep near-infrared survey of a bright-rimmed molecular cloud, BRC 14 (IC 1848A). The 10{sigma} limiting magnitude of the survey is 17.7mag at the K-band. Seventy-four sources are classified as young stellar object (YSO) candidates based on a near-infrared color-color diagram. The faintest YSO candidates may have masses on the order of tenths of the solar mass, assuming an age of 1Myr. We examined three values as indicators of star formation: fraction of the YSO candidates, extinctions of all sources, and near-infrared excesses of the YSO candidates. All indicators increase from outside of the rim to the center of the molecular cloud, which suggests that the formation of the low-mass stars in the BRC 14 region proceeds from outside to the center of the cloud.
- ID:
- ivo://CDS.VizieR/J/ApJ/672/398
- Title:
- JHK' photometry of M17 silhouette object
- Short Name:
- J/ApJ/672/398
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- To study how the structure of the envelopes of young stellar objects (YSOs) evolve, we carried out a deep JHK'-band imaging survey of the M17 star-forming region using a near-infrared camera and the Infrared Camera and Spectrograph with adaptive optics mounted on the Subaru Telescope. In this survey, we found 51 dark silhouettes against bright near-infrared nebula emissions as background lights. They are regarded as envelopes associated with YSOs due to their size and association with the YSOs. We derived size, morphology, extinction, and mass for each silhouette envelope.
- 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.
- ID:
- ivo://CDS.VizieR/J/AJ/129/2714
- Title:
- JHK photometry of M92 variable stars
- Short Name:
- J/AJ/129/2714
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present near-infrared (NIR) J-, H-, and K-band time series observations of the Galactic globular cluster (GGC) M92.
- ID:
- ivo://CDS.VizieR/J/AJ/111/1964
- Title:
- JHK photometry of NGC1333
- Short Name:
- J/AJ/111/1964
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of an extensive near-infrared (JHK) imaging survey of the NGC 1333 star forming region. Our survey covers an area more than 4 times larger than the previous imaging survey of this cloud reported by Aspin et al. (1994, Cat. <J/A+AS/106/165>) and is sufficiently sensitive to render an accurate census of the embedded stellar population in the cloud. We detected 275 sources with m_K_<14.5mag within the 432 square arcminute region surveyed.
