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5111. Photometry of M giant candidates in the Milky Way
ID:
ivo://CDS.VizieR/J/AJ/147/76
Title:
Photometry of M giant candidates in the Milky Way
Short Name:
J/AJ/147/76
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a new catalog of 404 M giant candidates found in the UKIRT Infrared Deep Sky Survey (UKIDSS). The 2400deg^2^ available in the UKIDSS Large Area Survey Data Release 8 resolve M giants through a volume four times larger than that of the entire Two Micron All Sky Survey. Combining near-infrared photometry with optical photometry and proper motions from the Sloan Digital Sky Survey yields an M giant candidate catalog with less M dwarf and quasar contamination than previous searches for similarly distant M giants. Extensive follow-up spectroscopy of this sample will yield the first map of our Galaxy's outermost reaches over a large area of sky. Our initial spectroscopic follow-up of ~30 bright candidates yielded the positive identification of five M giants at distances ~20-90kpc. Each of these confirmed M giants have positions and velocities consistent with the Sagittarius stream. The fainter M giant candidates in our sample have estimated photometric distances ~200kpc (assuming [Fe/H]=0.0), but require further spectroscopic verification. The photometric distance estimates extend beyond the Milky Way's virial radius, and increase by ~50% for each 0.5dex decrease in assumed [Fe/H]. Given the number of M giant candidates, initial selection efficiency, and volume surveyed, we loosely estimate that at least one additional Sagittarius-like accretion event could have contributed to the hierarchical build-up of the Milky Way's outer halo.
5112. Photometry of M31 globular cluster EXT8
ID:
ivo://CDS.VizieR/J/A+A/651/A102
Title:
Photometry of M31 globular cluster EXT8
Short Name:
J/A+A/651/A102
Date:
22 Feb 2022
Publisher:
CDS
Description:
We recently found the globular cluster (GC) EXT8 in M31 to have an extremely low metallicity of [Fe/H]=-2.91+/-0.04 using high-resolution spectroscopy. Here we present a colour-magnitude diagram (CMD) for EXT8, obtained with the Wide Field Camera 3 on board the Hubble Space Telescope. Compared with the CMDs of metal-poor Galactic GCs, we find that the upper red giant branch (RGB) of EXT8 is about 0.03mag bluer in F606W-F814W and slightly steeper, as expected from the low spectroscopic metallicity. The observed colour spread on the upper RGB is consistent with being caused entirely by the measurement uncertainties, and we place an upper limit of sigma(F606W-F814W)=0.015mag on any intrinsic colour spread. The corresponding metallicity spread can be up to sigma([Fe/H])=0.2dex or >0.7dex, depending on the isochrone library adopted. The horizontal branch (HB) is located mostly on the blue side of the instability strip and has a tail extending to at least M(F606W)=+3, as in the Galactic GC M15. We identify two candidate RR Lyrae variables and several UV-luminous post-HB/post-AGB star candidates, including one very bright (M(F300X)=-3.2) source near the centre of EXT8. The surface brightness of EXT8 out to a radius of 25 arcsec is well fitted by a Wilson-type profile with an ellipticity of epsilon=0.20, a semi-major axis core radius of 0.25", and a central surface brightness of 15.2mag per square arcsec in the F606W band, with no evidence of extra-tidal structure. Overall, EXT8 has properties consistent with it being a "normal", but very metal-poor GC, and its combination of relatively high mass and very low metallicity thus remains challenging to explain in the context of GC formation theories operating within the hierarchical galaxy assembly paradigm.
5113. Photometry of multiples at NAOR and ASV in 2012
ID:
ivo://CDS.VizieR/J/AJ/149/150
Title:
Photometry of multiples at NAOR and ASV in 2012
Short Name:
J/AJ/149/150
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using the 2m telescope of the Bulgarian National Astronomical Observatory at Rozhen, observations of 246 double or multiple stars were carried out during six nights in 2012. This is the seventh series of measurements of CCD frames of double and multiple stars obtained at Rozhen. Also in 2012, using the 0.6m telescope of the Serbian Astronomical Station on the mountain of Vidojevica, observations of 117 double or multiple stars were carried out during five nights. This is the second series of measurements of CCD frames of double and multiple stars obtained at this station. In this paper we present the results for the position angle and angular separation for 453 pairs and residuals for 105 pairs with published orbital elements or linear solutions. These observations have angular separations in the range from 1.50'' to 178.12'', with a median angular separation of 8.13''. We also present the recalculated linear solution for one pair and three linear solutions that have been calculated for the first time.
5114. Photometry of multiple stars at NAOR&ASV in 2015
ID:
ivo://CDS.VizieR/J/AJ/153/195
Title:
Photometry of multiple stars at NAOR&ASV in 2015
Short Name:
J/AJ/153/195
Date:
21 Oct 2021
Publisher:
CDS
Description:
Results of CCD observations of 154 double or multiple stars, made with the 2 m telescope of the Bulgarian National Astronomical Observatory at Rozhen over five nights in 2015, are presented. This is the ninth series of measurements of CCD frames obtained at Rozhen. We also present results of CCD observations of 323 double or multiple stars made with the 0.6 m telescope of the Serbian Astronomical Station on the mountain of Vidojevica over 23 nights in 2015. This is the fourth series of measurements of CCD frames obtained at this station. This paper contains the results for the position angle and angular separation for 801 pairs and residuals for 127 pairs with published orbital elements or linear solutions. The angular separations are in the range from 1.52" to 201.56", with a median angular separation of 8.26". We also present eight pairs that are measured for the first time and linear elements for five pairs.
5115. Photometry of nearby cluster galaxies
ID:
ivo://CDS.VizieR/J/ApJS/153/397
Title:
Photometry of nearby cluster galaxies
Short Name:
J/ApJS/153/397
Date:
21 Oct 2021
Publisher:
CDS
Description:
Photometric observations are presented for 8747 galaxies in the fields of 28 clusters with redshifts in the range 0.05<z<0.11 and spanning a wide range in Abell richness class. The primary motivation for this study is to provide a nearby sample of clusters whose galaxy populations can be used to provide an anchor point for evolutionary studies of cluster galaxy populations.
5116. Photometry of NGC 6171
ID:
ivo://CDS.VizieR/J/MNRAS/252/357
Title:
Photometry of NGC 6171
Short Name:
J/MNRAS/252/357
Date:
21 Oct 2021
Publisher:
CDS
Description:
B and V CCD photometry is presented for 1565 stars in the low-concentration globular cluster NGC6171=M107
5117. Photometry of NGC 2808
ID:
ivo://CDS.VizieR/J/A+AS/84/59
Title:
Photometry of NGC 2808
Short Name:
J/A+AS/84/59
Date:
21 Oct 2021
Publisher:
CDS
Description:
(no description available)
5118. Photometry of NGC 1962-65-66-70
ID:
ivo://CDS.VizieR/J/A+A/301/396
Title:
Photometry of NGC 1962-65-66-70
Short Name:
J/A+A/301/396
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present CCD data in the Johnson passbands B and V of the young association NGC 1962-65-66-70 in the Large Magellanic Cloud.
5119. Photometry of NGC 5053
ID:
ivo://CDS.VizieR/J/AJ/109/269
Title:
Photometry of NGC 5053
Short Name:
J/AJ/109/269
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present (V,B-V), (V,V-I), and (V,B-I) color-magnitude diagrams for NGC 5053, which is the most metal-poor globular cluster known in the galaxy. The horizontal branch (HB) is predominantly blueward of the RR Lyrae instability strip and the slope of the red giant branch (RGB) is relatively steep, both characteristic of a metal-poor system. Monte- Carlo simulations show that both the RGB and HB are underpopulated relative to those of the metal-poor cluster M15, indicative of the relatively lower total luminosity of NGC 5053. Based on the mean magnitude of stars located at the red and blue edges of the instability strip, we find V(HB) = 16.65 +/- 0.03. At this magnitude, polynomial fits to the cluster RGBs in the two measured colors yield (B-V)_g = 0.71 +/- 0.016 and (V-I)_g = 0.93 +/- 0.016. Using the BVI two-color diagram in a differential manner with respect to M68 and M15 gives a reddening of E(B-V) = 0.06 +/- 0.02 for NGC 5053. We have utilized these quantities to extend the calibration of the simultaneous reddening and metallicity method [Sarajedini, AJ, 107, 618 (1994a)] to [Fe/H] = -2.4. Another feature of the color-magnitude diagram that is evident is the rich population of blue straggler stars (BSSs). We are able to recover 22 of 24 previously known BSSs, and we have added 3 more BSSs.
5120. Photometry of NGC 3109 carbon stars
ID:
ivo://CDS.VizieR/J/A+A/410/795
Title:
Photometry of NGC 3109 carbon stars
Short Name:
J/A+A/410/795
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a CFH12K wide field survey of the carbon star population in and around NGC 3109. Carbon stars, the brightest members of the intermediate-age population, were found nearly exclusively in and near the disk of NGC 3109, ruling out the existence of an extensive intermediate-age halo like the one found in NGC 6822. Over 400 carbon stars identified have M_I_=-4.71, confirming the nearly universality of mean magnitude of C star populations in Local Group galaxies. Star counts over the field reveal that NGC 3109 is a truncated disk shaped galaxy without an extensive stellar halo. The minor axis star counts reach the foreground density between 4' and 5', a distance that can be explained by an inclined disk rather than a spheroidal halo. We calculate a global C/M ratio of 1.75+/-0.20, a value expected for such a metal poor galaxy.