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1981. Photoelectric UBV from HK survey. II.
ID:
ivo://CDS.VizieR/J/PASP/103/973
Title:
Photoelectric UBV from HK survey. II.
Short Name:
J/PASP/103/973
Date:
21 Oct 2021
Publisher:
CDS
Description:
Photoelectric UBV photometry is presented for a sample of 165 stars drawn from the extension of the HK objective-prism/interference-filter survey of Beers, Preston and Shectman (1985AJ.....90.2089B) to the northern galactic hemisphere. These results are part of continuing follow-up observations of candidate metal-deficient and horizontal-branch field stars and other interesting stars identified in the survey. A complete set of photometric observations is now available for three of the 25-square-degree survey fields. We estimate that the complete photometric sample of 299 northern HK candidates obtained to date contains on order 90 main-sequences turnoff, subgiant, and giant stars with [Fe/H]<=-1.0, 50 field blue horizontal-branch stars, and 30 stars with the photometric properties of field blue stragglers.
1982. Photographic astrometry. VIII.
ID:
ivo://CDS.VizieR/J/AJ/108/2338
Title:
Photographic astrometry. VIII.
Short Name:
J/AJ/108/2338
Date:
21 Oct 2021
Publisher:
CDS
Description:
300 trigonometric parallaxes, 15 revised binary-star orbits, and 24 mass ratios are listed and annotated.
1983. Photographic observations of variable stars in M9
ID:
ivo://CDS.VizieR/J/AJ/89/1707
Title:
Photographic observations of variable stars in M9
Short Name:
J/AJ/89/1707
Date:
21 Oct 2021
Publisher:
CDS
Description:
New observations from the southern hemisphere have been used to check the periods for the 11 RR Lyrae variables in and around the globular cluster Messier 9. The periods were determined previously with data from northern observatories where M9 can only be observed over a small range in hour angle. Three of the eleven published periods were found to be in error. As a result of this, the mean period of the RRc variables has been revised from 0.279d to 0.341d, the mean period of the RRab variables has been revised from 0.614d to 0.621d,and a star previously believed to be an RR Lyrae has been reclassified as a Population II Cepheid. One of the RRc variables may be a double-mode pulsator. Another variable was studied, but the data were not sufficient for determining its period.
1984. Photographic study of A2197 and A2199
ID:
ivo://CDS.VizieR/J/MNRAS/239/459
Title:
Photographic study of A2197 and A2199
Short Name:
J/MNRAS/239/459
Date:
21 Oct 2021
Publisher:
CDS
Description:
Radii, b26 magnitudes, (b-r) colors, position angles, and ellipticities have been measured on the plates of Palomar 48-inch Schmidt telescope taken in May 1976, for 6925 galaxies in a 5-sq deg field enclosing the close pair of rich clusters A2197 and A2199.
1985. Photometric and astrometric study of NGC 6530
ID:
ivo://CDS.VizieR/J/A+A/623/A25
Title:
Photometric and astrometric study of NGC 6530
Short Name:
J/A+A/623/A25
Date:
21 Oct 2021
Publisher:
CDS
Description:
NGC 6530 is a young cluster, with a complex morphology and star-formation history. We present a statistical study of its global properties, using a new, large list of candidate members down to masses of 0.2-0.4M_{sun}_ and Gaia DR2 astrometry. We consider a larger sky region compared to previous studies, to investigate the entire cluster until its periphery, including any diffuse population all around the main cluster. We study the distribution of extinction and age across the different regions, and obtain constraints on the star-formation history. We also study the dynamics of cluster members. Cluster membership was determined on the basis of literature X-ray data, H{alpha} emission, near-IR and UV excesses from the VPHAS+ and UKIDSS photometric surveys and published near-IR catalogs, and Gaia DR2 astrometry; moreover, we used a method for photometric selection of M-type pre-main-sequence cluster members, which we recently developed and used for other star-formation regions. The list of candidates includes nearly 3700 stars, of which we estimate approximately 2700 to be genuine NGC 6530 members. Using Gaia parallaxes, the cluster distance is found to be 1325pc, with errors of 0.5% (statistical) and 8.5% (systematic), in agreement with previous determinations. The cluster morphology and boundaries are established with great confidence, from the agreement between the subsamples of members selected using different criteria. There is no diffuse population of members around the cluster, but there are minor condensations of true members in addition to the two main groups in the cluster core and in the Hourglass nebula. Two such subgroups are spatially associated with the stars 7 Sgr (F2II-III) and HD 164536 (O7.5V). There is a definite pattern of sequential star formation across the cluster, within an age range from less than 0.5Myr to ~5Myr. Extinction is spatially non-uniform, with part of the population still embedded or obscured by thick dust. The precise Gaia proper motion data indicate that the NGC 6530 parent cloud collided with the Galactic plane around 4Myr ago, and we suggest that event as the trigger of the bulk of star formation in NGC 6530. The internal cluster dynamics is also partially resolved by the Gaia data, indicating expansion of the main cluster population with respect to its center.
1986. Photometric and Spectroscopic Databases for LSS Stars
ID:
ivo://CDS.VizieR/V/92A
Title:
Photometric and Spectroscopic Databases for LSS Stars
Short Name:
V/92A
Date:
21 Oct 2021
Publisher:
CDS
Description:
This catalog contains databases of published photoelectric UBVbeta data, MK-system spectral classifications, and Stroemgren four-color uvby photometry for objects in the Stephenson-Sanduleak "Luminous Stars in the Southern Milky Way" catalog (LSS catalog). The catalog contains mostly OB stars and A and F supergiants. These databases have been compiled from the literature.
1987. Photometric Calibration of SNLS
ID:
ivo://CDS.VizieR/J/A+A/506/999
Title:
Photometric Calibration of SNLS
Short Name:
J/A+A/506/999
Date:
21 Oct 2021
Publisher:
CDS
Description:
This is the photometric calibration of the SuperNova Legacy Survey (SNLS) three year dataset. The SNLS corresponds to the DEEP component of the larger Canada-France-Hawaii Telescope Legacy Survey (CFHTLS). The SNLS repeatedly monitors four one square degree fields (labeled D[1-4]) with the MegaCam wide-field imager, in the g, r, i and z bands. u-band observations of the same fields are also available, although not formally part of the SNLS dataset. The non-uniformities of the MegaCam imager photometric response have been mapped as a function of the position on the focal plane. The fluxes, measured on the survey images processed with the CFHT Elixir pipeline, have been corrected for these non-uniformities in order to obtain measurements that are uniform at the ~1% level. The MegaCam passband transmissions were found to be non-uniform, the filters being 3 to 6 nanometers bluer on the edges of the camera than on the center. This result agrees with the filter scans provided by the filter manufacturer (Sagem/REOSC). This has important consequences on the definition of the MegaCam magnitudes: the natural magnitude system depends on the focal plane location where the observations were made. In order not to break the connection between calibrated magnitudes and their physical flux counterparts, we chose to report the *natural magnitudes* of each object, measured in the MegaCam passbands, at the focal plane location where the object was observed. We call this system, "Local Natural Magnitudes". The non-uniformities of the MegaCam effective passbands are small and, for main sequence stellar objects, they may be accounted for using linear color corrections. The relation between the Local Natural Magnitudes of a given star, observed at two locations x_0 and x of the focal plane are: g|x = g|x_0 + dk_g_gr(x) * ( (g-r)|x_0 - (g-r)BD+17|x_0 ) ... z|x = z|x_0 + dk_z_iz(x) * ( (i-z)|x_0 - (i-z)BD+17|x_0 ) where the dk(x) are (position dependant) color terms. We provide dk(x) maps for each MegaCam band (see below). The SNLS 3 year calibration relies on the (Landolt, 1992AJ....104..340) standard star catalog. Landolt fields are observed during each photometric night along with the SNLS fields. Zero-points are derived from these observations. Stable and isolated stars are detected on the SNLS fields and selected as "tertiary standards". The calibrated magnitudes of each tertiary standard obtained under photometric conditions are combined to produce a calibration catalog for each SNLS field. To interpret the tertiary standard magnitudes as physical fluxes, we need a primary standard, i.e. a star with known MegaCam magnitudes and whose spectral energy distribution has been measured absolutely. The SNLS uses BD+17 4708 whose SED has been measured in Bohlin & Gilliland, 2004, Cat. <J/AJ/128/3053> using the HST STIS and NICMOS spectrographs. BD+17 4708 has not been directly observed by SNLS, however, its MegaCam magnitudes were inferred from its known Landolt magnitudes (this paper, table 7). The tertiary star Local Natural Magnitudes are defined so that the associated physical broadband flux f|x is given by: f|x = 10^{-0.4*(m|x-m_ref_)}^*{int}[S_ref(l)_*T(l;x)]dl where m|x is the tertiary star magnitudes at location x on the focal plane, m_ref_ is the MegaCam magnitude of BD+17 4708 (at the center of the focal plane, see table 7 of this paper), S_ref(l)_ is the SED of BD+17 4708 measured in 2004AJ....128.3053B, and T(l;x) is the effective passband of MegaCam at location x. Attached is all the necessary information to tie MegaCam observations to this system. We provide (a) the griz magnitudes of the SNLS tertiary standards for all four SNLS fields (b) the MegaCam open transmission and the ugriz MegaCam filter scans at various position along a diagonal (c) the final uncertainty budget in the form of 3 covariance matrices. The u-band observations of the SNLS DEEP fields are not formally part of the SNLS. Nevetheless we give u-band magnitudes for a subset of the SNLS tertiary stars.
1988. Photometric catalogs for ECDF-S and CDF-N
ID:
ivo://CDS.VizieR/J/ApJ/742/3
Title:
Photometric catalogs for ECDF-S and CDF-N
Short Name:
J/ApJ/742/3
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present an analysis of deep multiwavelength data for z~0.3-3 starburst galaxies selected by their 70um emission in the Extended-Chandra Deep Field-South and Extended Groth Strip. We identify active galactic nuclei (AGNs) in these infrared sources through their X-ray emission and quantify the fraction that host an AGN. Lastly, we investigate the ratio between the supermassive black hole accretion rate (inferred from the AGN X-ray luminosity) and the bulge growth rate of the host galaxy (approximated as the SFR) and find that, for sources with detected AGNs and star formation (and neglecting systems with low star formation rates to which our data are insensitive), this ratio in distant starbursts agrees well with that expected from the local scaling relation assuming the black holes and bulges grew at the same epoch. These results imply that black holes and bulges grow together during periods of vigorous star formation and AGN activity.
1989. Photometric catalogue of CALIFA galaxies
ID:
ivo://CDS.VizieR/J/MNRAS/477/845
Title:
Photometric catalogue of CALIFA galaxies
Short Name:
J/MNRAS/477/845
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present an extensive compendium of photometrically determined structural properties for all Calar Alto Legacy Integral Field spectroscopy Area (CALIFA)galaxies in the third data release (DR3). We exploit Sloan Digital Sky Survey (SDSS) images in order to extract one-dimensional (1D) gri surface brightness profiles for all CALIFA DR3 galaxies. We also derive a variety of non-parametric quantities and parametric models fitted to 1D i-band profiles. The galaxy images are decomposed using the 2D bulge-disc decomposition programs IMFIT and GALFIT. The relative performance and merit of our 1D and 2D modelling approaches are assessed. Where possible, we compare and augment our photometry with existing measurements from the literature. Close agreement is generally found with the studies of Walcher et al. (2014A&A...569A...1W) and Mendez-Abreu et al. (2017A&A...598A..32M, Cat. J/A+A/598/A32), though some significant differences exist. Various structural metrics are also highlighted on account of their tight dispersion against an independent variable, such as the circular velocity.
1990. Photometric Classification Catalogue of SDSS DR7
ID:
ivo://CDS.VizieR/J/MNRAS/419/80
Title:
Photometric Classification Catalogue of SDSS DR7
Short Name:
J/MNRAS/419/80
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a catalogue of about six million unresolved photometric detections in the Sloan Digital Sky Survey (SDSS) Seventh Data Release, classifying them into stars, galaxies and quasars. We use a machine learning classifier trained on a subset of spectroscopically confirmed objects from 14th to 22nd magnitude in the SDSS i band. Our catalogue consists of 2430625 quasars, 3544036 stars and 63586 unresolved galaxies from 14th to 24th magnitude in the SDSS i-band. Our algorithm recovers 99.96 per cent of spectroscopically confirmed quasars and 99.51 per cent of stars to i~21.3 in the colour window that we study. The level of contamination due to data artefacts for objects beyond i=21.3 is highly uncertain and all mention of completeness and contamination in the paper are valid only for objects brighter than this magnitude. However, a comparison of the predicted number of quasars with the theoretical number counts shows reasonable agreement.