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1891. JHKs photometry of Sculptor dSph galaxy
ID:
ivo://CDS.VizieR/J/MNRAS/414/3492
Title:
JHKs photometry of Sculptor dSph galaxy
Short Name:
J/MNRAS/414/3492
Date:
21 Oct 2021
Publisher:
CDS
Description:
JHKs photometry is presented for a 35 arcmin^2^ field centred on the Sculptor dwarf spheroidal galaxy. With the aid of published kinematic data definite galaxy members are identified and the width in J-K of the colour-magnitude diagram is shown to be consistent with an old population of stars with a large range in metal abundance. We identify two Asymptotic Giant Branch variables, both carbon Miras, with periods of 189 and 554d, respectively, and discuss their ages, metallicities and mass-loss as well as their positions in the Mira period-luminosity diagram. There is evidence for a general period-age relation for Local Group Miras. The mass-loss rate for the 554d variable, MAG29, appears to be consistent with that found for Miras of comparable period in other Local Group galaxies.
1892. JHK variable stars in M33
ID:
ivo://CDS.VizieR/J/MNRAS/411/263
Title:
JHK variable stars in M33
Short Name:
J/MNRAS/411/263
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have conducted a near-infrared monitoring campaign at the UK InfraRed Telescope (UKIRT), of the Local Group spiral galaxy M 33 (Triangulum). The main aim was to identify stars in the very final stage of their evolution, and for which the luminosity is more directly related to the birth mass than the more numerous less-evolved giant stars that continue to increase in luminosity. The most extensive dataset was obtained in the K-band with the UIST instrument for the central 4'x4' (1kpc^2^) --- this contains the nuclear star cluster and inner disc. These data, taken during the period 2003-2007, were complemented by J- and H-band images. Photometry was obtained for 18,398 stars in this region; of these, 812 stars were found to be variable, most of which are Asymptotic Giant Branch (AGB) stars. Our data were matched to optical catalogues of variable stars and carbon stars, and to mid-infrared photometry from the Spitzer Space Telescope. In this first of a series of papers, we present the methodology of the variability survey and the photometric catalogue, which is made publicly available at the Centre de Donnees astronomiques de Strasbourg (CDS), and discuss the properties of the variable stars. Most dusty AGB stars had not been previously identified in optical variability surveys, and our survey is also more complete for these types of stars than the Spitzer survey.
1893. JK photometry in SA 57-6575, Her 1-5677 fields
ID:
ivo://CDS.VizieR/J/ApJ/505/50
Title:
JK photometry in SA 57-6575, Her 1-5677 fields
Short Name:
J/ApJ/505/50
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have used the Keck 10m telescope to count objects as a function of image size in two high Galactic latitude fields covering 1.5arcmin^2^ and reaching 50% completeness depths of K=24 and J=24.5 for stellar sources. Our counts extend ~1mag deeper in K than those of surveys with other telescopes; complement other Keck surveys in the K-band that provide counts at comparable or shallower depths but that have not utilized image structure; and extend by several magnitudes the J-band counts from brighter surveys using smaller telescopes that cover larger areas.
1894. JKs, i'g'r' photometry of C stars in NGC 6822
ID:
ivo://CDS.VizieR/J/A+A/456/905
Title:
JKs, i'g'r' photometry of C stars in NGC 6822
Short Name:
J/A+A/456/905
Date:
21 Oct 2021
Publisher:
CDS
Description:
From a 2{deg}x2{deg} survey of NGC 6822 we have previously established that this Local Group dwarf irregular galaxy possesses a huge spheroid having more than one degree in length. This spheroid is in rotation but its rotation curve is known only within ~15' from the center. It is therefore critical to identify bright stars belonging to the spheroid to characterize, as far as possible, its outer kinematics. We use the new wide field near infrared imager CPAPIR, operated by the SMARTS consortium, to acquire J, K_s_ images of two 34.8'x34.8' areas in the outer spheroid to search for C stars. The colour diagram of the fields allows the identification of 192 C stars candidates but a study of the FWHM of the images permits the rejection of numerous non-stellar objects with colours similar to C stars. We are left with 75 new C stars, their mean K_s_ magnitude and mean colour are similar to the bulk of known NGC 6822 C stars. This outer spheroid survey confirms that the intermediate-age AGB stars are a major contributor to the stellar populations of the spheroid. The discovery of some 50 C stars well beyond the limit of the previously known rotation curve calls for a promising spectroscopic follow-up to a major axis distance of 40'.
1895. JKs photometry of C stars in IC10 and WLM
ID:
ivo://CDS.VizieR/J/A+A/474/35
Title:
JKs photometry of C stars in IC10 and WLM
Short Name:
J/A+A/474/35
Date:
21 Oct 2021
Publisher:
CDS
Description:
The selection of AGB C and M stars from NIR colours has been done in recent years using adjustable criteria that are in needs of standardization if one wants to compare, in a coherent manner, properties of various populations. We intend to assess the NIR colour technique to identify C and M stars. We compare the NIR colours of several C stars previously identified from spectroscopy or narrow band techniques in WLM, IC 10 and NGC 6822. We demonstrate that very few M stars have (J-K)_0_>1.4 but a non negligible number of C stars are bluer than this limit. Thus, counts of M and C stars based on such limit do not produce pure samples. C/M ratios determined from NIR colours must be regarded as underestimates mainly because the M numbers include many warm C stars and also K stars if no blue limit is considered.
1896. JKs photometry of local universe galaxies
ID:
ivo://CDS.VizieR/J/ApJS/149/327
Title:
JKs photometry of local universe galaxies
Short Name:
J/ApJS/149/327
Date:
21 Oct 2021
Publisher:
CDS
Description:
This paper presents empirical results from a deep imaging survey of galaxies in the local universe at the J and Ks wavelengths. Three hundred ninety-one images have been obtained and calibrated using the same camera and filter set with the Steward Observatory 1.6m Kuiper Telescope on Mount Bigelow and the 2.3m Bok Telescope on Kitt Peak. The limiting magnitude is typically 22mag/arcsec at J and 21mag/arcsec at Ks. The central surface brightness, apparent magnitudes, sizes, scale lengths, and inclinations are tabulated from measurements made using these data. The purpose of this paper is to provide basic near-infrared data on a variety of galaxy types.
1897. JKs photometry of WLM galaxy carbon stars
ID:
ivo://CDS.VizieR/J/A+A/466/501
Title:
JKs photometry of WLM galaxy carbon stars
Short Name:
J/A+A/466/501
Date:
21 Oct 2021
Publisher:
CDS
Description:
We identify the rich carbon star population of the Magellanic-type dwarf irregular galaxy WLM (Wolf-Lundmark-Melotte) and study its photometric properties from deep near-IR observations. The galaxy also exhibits a clear presence of oxygen-rich population. We derive a carbon to M-star ratio of C/M=0.56+/-0.12, relatively high in comparison with many galaxies. The spatial distribution of the AGB stars in WLM hints at the presence of two stellar complexes with a size of a few hundred parsecs. Using the HI map of WLM and the derived gas-to-dust ratio for this galaxy N(HI)/E(B-V)=60+/-10[10^21^at/cm^2^/mag] we re-determined the distance modulus of WLM from the IR photometry of four known Cepheids, obtaining (m-M)0=24.84+/-0.14mag. In addition, we determine the scale length of 0.75+/-0.14kpc of WLM disk in the J-band.
1898. j-M law from dwarf to massive spirals
ID:
ivo://CDS.VizieR/J/A+A/612/L6
Title:
j-M law from dwarf to massive spirals
Short Name:
J/A+A/612/L6
Date:
21 Oct 2021
Publisher:
CDS
Description:
In a {LAMBDA} CDM Universe, the specific stellar angular momentum (j*) and stellar mass (M*) of a galaxy are correlated as a consequence of the scaling existing for dark matter haloes (jh{prop.to}2/3). The shape of this law is crucial to test galaxy formation models, which are currently discrepant especially at the lowest masses, allowing to constrain fundamental parameters, such as, for example, the retained fraction of angular momentum. In this study, we accurately determine the empirical j*-M* relation (Fall relation) for 92 nearby spiral galaxies (from S0 to Irr) selected from the Spitzer Photometry and Accurate Rotation Curves (SPARC) sample in the unprecedented mass range 7<~logM*/M_{sun}_<~11.5. We significantly improve all previous estimates of the Fall relation by determining j* profiles homogeneously for all galaxies, using extended HI rotation curves, and selecting only galaxies for which a robust j* could be measured (converged j*(<R) radial profile). We find the relation to be well described by a single, unbroken power-law j*{alpha}M*^{alpha}^ over the entire mass range, with {alpha}=0.55+/-0.02 and orthogonal intrinsic scatter of 0.17+/-0.01dex. We finally discuss some implications of this fundamental scaling law for galaxy formation models and, in particular, the fact that it excludes models in which discs of all masses retain the same fraction of the halo angular momentum.
1899. j-M relation for disk and bulge type galaxies
ID:
ivo://CDS.VizieR/J/ApJ/868/133
Title:
j-M relation for disk and bulge type galaxies
Short Name:
J/ApJ/868/133
Date:
21 Oct 2021
Publisher:
CDS
Description:
We show that the stellar specific angular momentum j_*_, mass M_*_, and bulge fraction {beta}_*_ of normal galaxies of all morphological types are consistent with a simple model based on a linear superposition of independent disks and bulges. In this model, disks and bulges follow scaling relations of the form j_*_d{propto}M_*_d^{alpha}^ and j_*_b{propto}M_*_b^{alpha}^ with {alpha}=0.67+/-0.07 but offset from each other by a factor of 8+/-2 over the mass range 8.9<=log(M_*/M_{sun})<=11.8. Separate fits for disks and bulges alone give {alpha}=0.58+/-0.10 and {alpha}=0.83+/-0.16, respectively. This model correctly predicts that galaxies follow a curved 2D surface in the 3D space of log(j_*_), log(M_*_), and {beta}_*_. We find no statistically significant indication that galaxies with classical and pseudo bulges follow different relations in this space, although some differences are permitted within the observed scatter and the inherent uncertainties in decomposing galaxies into disks and bulges. As a byproduct of this analysis, we show that the j_*_-M_*_ scaling relations for disk-dominated galaxies from several previous studies are in excellent agreement with each other. In addition, we resolve some conflicting claims about the {beta}_*_ dependence of the j_*_-M_*_ scaling relations. The results presented here reinforce and extend our earlier suggestion that the distribution of galaxies with different {beta}_*_ in the j_*_-M_*_ diagram constitutes an objective, physically motivated alternative to subjective classification schemes such as the Hubble sequence.
1900. J-PLUS Ly{alpha}-emitting candidates
ID:
ivo://CDS.VizieR/J/A+A/643/A149
Title:
J-PLUS Ly{alpha}-emitting candidates
Short Name:
J/A+A/643/A149
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the photometric determination of the bright-end of the Ly{alpha} luminosity function (at L_Ly{alpha}_>~10^43.5^erg/s) within four redshifts windows ({Delta}z<0.16) in the interval 2.2<~z<~3.3. Our work is based on the Javalambre Photometric Local Universe Survey (J-PLUS) first data-release, which provides multiple narrow-band measurements over ~1000deg^2^, with limiting magnitude ~22. Theanalysis of high-z Ly{alpha}-emitting sources over such a wide area is unprecedented, and allows to select a total of ~14500 hyper-bright(L_Ly{alpha}_>10^43.3^erg/s) Ly{alpha}-emitting candidates. We test our selection with two spectroscopic follow-up programs at the GTC telescope,which confirm as line-emitting sources ~89% of the targets, with ~64% being genuine z~2.2 QSOs. We extend the 2.2<~z<~3.3 Ly{alpha} luminosity function for the first time above L_Ly{alpha}_~10^44^erg/s and down to densities of ~10^-8^Mpc^-3^. Our results unveil with high detail the Schechter exponential-decay of the brightest-end of the Ly{alpha} LF, complementing the power-law component of previous LF determinations at 43.3<~Log10(L_Ly{alpha}_/(erg/s))<~44. We measure {PHI}*=(3.33+/-0.19)x10^-6^, Log(L*)=44.65+/-0.65 and {alpha}=-1.35+/-0.84 as an average over the redshifts we probe. These values are significantly different than the typical Schechter parameters measured for the Ly{alpha} LF of high-z star-forming LAEs. This suggests that z>2 AGN/QSOs (likely dominant in our samples) are described by a structurally different LF than z>2 star-forming LAEs, namely with L*_QSOs_~100 L*_LAEs_ and {PHI}*_QSOs_~10^-3^{PHI}*_LAEs_. Finally, our method identifies very efficiently as high-z line-emitters sources without previous spectroscopic confirmation, currently classified as stars (~2000 objects in each redshift bin, on average). Assuming a large predominance of Ly{alpha}-emitting AGN/QSOs in our samples, this supports the scenario by which these are the most abundant class of z>~2 Ly{alpha} emitters at L_Ly{alpha}_>~10^43.3^erg/s.

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