- 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.
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- ID:
- ivo://CDS.VizieR/J/MNRAS/373/781
- Title:
- JHK photometry of faint standard stars
- Short Name:
- J/MNRAS/373/781
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- JHK photometry in the Mauna Kea Observatories (MKO) near-infrared system is presented for 115 stars. Of these stars, 79 are United Kingdom Infrared Telescope (UKIRT) standards from Hawarden et al. (2001MNRAS.325..563H), and 42 are Las Campanas Observatory (LCO, or NICMOS) standards from Persson et al. The average brightness of the sample in all three bandpasses is 11.5mag, with a range between 10 and 15. The average number of nights each star was observed is 4, and the average of the internal error of the final results is 0.011mag. These JHK data agree with those reported by other groups to 0.02mag, for stars in common, which is consistent with the uncertainties. The measurements are used to derive colour transformations between the MKO JHK photometric system and the UKIRT, LCO and Two Micron All-Sky Survey (2MASS) systems.
- 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/A+AS/97/587
- Title:
- JHK photometry of Galactic center stars
- Short Name:
- J/A+AS/97/587
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present K-counts and JHK detailed photometry for a number of stars with K<=+9.0 in three clear regions near the galactic centre. These regions are all located approximately at l~0.0 and at latitudes b~-3.5,-4.0 and 4.5 respectively. Their Cumulative Counts Functions (CCF's) are formed, and with the aid of an exponential disk model for the Galaxy they are separated into disk and bulge CCF. As for the case in Baade's Window (BW) (Ruelas-Mayorga & Teague, 1992A&AS...95..379R) the disk is dominant at bright magnitudes whereas the bulge dominates at the faint end of the CCF. The slope of the bulge CCF is steeper than that for the disk in all three cases corroborating the result obtained for BW. The two colour JHK diagram and the K vs J-K diagram for the three regions show that the stellar population in these areas is similar to that studied in BW by us and by Frogel & Whitford (1987ApJ...320..199F). An average value of E(J-K)~0.42mag for the reddening is obtained, which is somewhat larger than that found for BW (0.27). Finally it is shown that at K<=+9.0, the disk population may be accounted for by those sources with J-K<=+1.6 whereas the bulge population presents values for J-K in excess of +1.6.
- ID:
- ivo://CDS.VizieR/J/AJ/133/1287
- Title:
- JHK photometry of 24 Galactic globular clusters
- Short Name:
- J/AJ/133/1287
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present near-IR color-magnitude diagrams and physical parameters for a sample of 24 Galactic globular clusters toward the bulge. In this paper we discuss the properties of 12 new clusters (out of the 24) in addition to those previously studied and published by our group. The compilation includes measurements of the cluster reddening, distance, photometric metallicity, horizontal branch red clump, and red giant branch morphological (e.g., mean ridgelines) and evolutionary (e.g., bump and tip) features. The compilation is available in electronic form on the World Wide Web, and it will be updated regularly.
- 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).
- 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.
