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3171. JHK photometry of 36 Galactic globular clusters
ID:
ivo://CDS.VizieR/J/MNRAS/402/1729
Title:
JHK photometry of 36 Galactic globular clusters
Short Name:
J/MNRAS/402/1729
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present near-infrared colour-magnitude diagrams and physical parameters for a sample of 12 galactic globular clusters located towards the inner bulge region. For each cluster we provide measurements of the reddening, distance and photometric metallicity and of the luminosity of the horizontal branch red clump and the red giant branch bump and tip. The sample discussed here, together with that presented in Valenti, Ferraro & Origlia (2007, Cat. J/AJ/133/1287), represents the largest homogeneous catalogue of bulge globular clusters (comprising ~80 per cent of the entire bulge cluster population) ever studied. The compilation is available in electronic form on the World Wide Web (http://www.bo.astro.it/~GC/ir_archive).
3172. JHK photometry of 9 gamma-ray burst fields
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.
3173. JHK photometry of globular clusters. III.
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.
3174. JHK photometry of 913 globular clusters in M31
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}_.
3175. JHK photometry of IC 1613 AGB stars
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.
3176. JHK photometry of Leo I AGB and red giants
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.
3177. JHK Photometry of Liller 1
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.
3178. JHK photometry of low-mass stars in BRC 14
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.
3179. JHK' photometry of M17 silhouette object
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.
3180. JHK photometry of M31 spiral arm
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.