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2271. MUSYC optical imaging in ECDF-S
ID:
ivo://CDS.VizieR/J/ApJS/189/270
Title:
MUSYC optical imaging in ECDF-S
Short Name:
J/ApJS/189/270
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present deep optical 18-medium-band photometry from the Subaru telescope over the ~30'x30' Extended Chandra Deep Field-South, as part of the Multiwavelength Survey by Yale-Chile (MUSYC). This field has a wealth of ground- and space-based ancillary data, and contains the GOODS-South field and the Hubble Ultra Deep Field. We combine the Subaru imaging with existing UBVRIzJHK and Spitzer IRAC images to create a uniform catalog. Detecting sources in the MUSYC "BVR" image we find ~40,000 galaxies with R_AB_<25.3, the median 5{sigma} limit of the 18 medium bands. Photometric redshifts are determined using the EAzY code and compared to ~2000 spectroscopic redshifts in this field. The medium-band filters provide very accurate redshifts for the (bright) subset of galaxies with spectroscopic redshifts, particularly at 0.1<z<1.2 and at z~>3.5. For 0.1<z<1.2, we find a 1{sigma} scatter in {DELTA}z/(1+z) of 0.007, similar to results obtained with a similar filter set in the COSMOS field. As a demonstration of the data quality, we show that the red sequence and blue cloud can be cleanly identified in rest-frame color-magnitude diagrams at 0.1<z<1.2. We find that ~20% of the red sequence galaxies show evidence of dust emission at longer rest-frame wavelengths. The reduced images, photometric catalog, and photometric redshifts are provided through the public MUSYC Web site (http://www.astro.yale.edu/MUSYC/).
2272. MUSYC: optical source catalog
ID:
ivo://CDS.VizieR/J/ApJS/162/1
Title:
MUSYC: optical source catalog
Short Name:
J/ApJS/162/1
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present UBVRIz' optical images taken with MOSAIC on the CTIO 4m telescope of the 0.32{deg}^2^ Extended Hubble Deep Field-South. This is one of four fields comprising the MUSYC survey, which is optimized for the study of galaxies at z=3, active galactic nucleus (AGN) demographics, and Galactic structure. Our methods used for astrometric calibration, weighted image combination, and photometric calibration in AB magnitudes are described. We calculate corrected aperture photometry and its uncertainties and find through tests that these provide a significant improvement upon standard techniques. Our photometric catalog of 62,968 objects is complete to a total magnitude of R_AB_=25, with R-band counts consistent with results from the literature.
2273. MUTA; the {mu}Tau Association
ID:
ivo://CDS.VizieR/J/ApJ/903/96
Title:
MUTA; the {mu}Tau Association
Short Name:
J/ApJ/903/96
Date:
15 Mar 2022
Publisher:
CDS
Description:
We present an analysis of the newly identified {mu}Tau Association (MUTA) of young stars at ~150pc from the Sun that is part of the large Cas-Tau structure, coeval and comoving with the {alpha}Persei cluster. This association is also located in the vicinity of the Taurus-Auriga star-forming region and the Pleiades association, although it is unrelated to them. We identify more than 500 candidate members of MUTA using Gaia DR2 data and the BANYAN {Sigma} tool, and we determine an age of 62{+/-}7Myr for its population based on an empirical comparison of its color-magnitude diagram sequence with those of other nearby young associations. The MUTA association is related to the Theia 160 group of Kounkel & Covey and corresponds to the e Tau group of Liu et al. It is also part of the Cas-Tau group of Blaauw. As part of this analysis, we introduce an iterative method based on spectral templates to perform an accurate correction of interstellar extinction of Gaia DR2 photometry, needed because of its wide photometric bandpasses. We show that the members of MUTA display an expected increased rate of stellar activity and faster rotation rates compared with older stars, and that literature measurements of the lithium equivalent width of nine G0- to K3-type members are consistent with our age determination. We show that the present- day mass function of MUTA is consistent with other known nearby young associations. We identify WD0340+103 as a hot, massive white dwarf remnant of a B2 member that left its planetary nebula phase only 270000yr ago, posing an independent age constraint of 60_-6_^+8^ Myr for MUTA, consistent with our isochrone age. This relatively large collection of comoving young stars near the Sun indicates that more work is required to unveil the full kinematic structure of the complex of young stars surrounding {alpha} Persei and Cas-Tau.
2274. M68 variable star light curves
ID:
ivo://CDS.VizieR/II/331
Title:
M68 variable star light curves
Short Name:
II/331
Date:
21 Oct 2021
Publisher:
CDS
Description:
110 plates of the globular cluster M68, taken during 1951 to 1953 with the 24-inch reflector of the station of Lojano, have been the subject of a photometric investigation.
2275. M30 V1-V3 variable light curves
ID:
ivo://CDS.VizieR/J/other/MmSAI/20.63
Title:
M30 V1-V3 variable light curves
Short Name:
J/other/MmSAI/20
Date:
21 Oct 2021
Publisher:
CDS
Description:
175 plates of the globular cluster M30 in Capricornus, taken mainly in the years 1946, 1947 and 1948, with the 24-inch reflector, have been the object of a photometric investigation.
2276. MWC 560 UBV(RI)c light curves
ID:
ivo://CDS.VizieR/J/other/NewA/49.43
Title:
MWC 560 UBV(RI)c light curves
Short Name:
J/other/NewA/49.
Date:
21 Oct 2021
Publisher:
CDS
Description:
After 26 years from the major event of 1990, in early 2016 the puzzling symbiotic binary MWC 560 has gone into a new and even brighter outburst. We present our tight BVRCIC photometric monitoring of MWC 560 (451 independent runs distributed over 357 different nights), covering the 2005-2016 interval, and the current outburst in particular. A stricking feature of the 2016 outburst has been the suppression of the short term chaotic variability during the rise toward maximum brightness, and its dominance afterward with an amplitude in excess of 0.5mag. Similar to the 1990 event when the object remained around maximum brightness for ~6 months, at the time Solar conjunction prevented further observations of the current outburst, MWC 560 was still around maximum, three months past reaching it. We place our observations into a long term context by combining with literature data to provide a complete 1928-2016 lightcurve. Some strong periodicities are found to modulate the optical photometry of MWC 560. A period of 1860-days regulate the occurence of bright phases at BVRC bands (with exactly 5.0 cycles separating the 1990 and 2016 outbursts), while the peak brightness attained during bright phases seems to vary with a ~9570-days cycle. A clean 331-day periodicity modulate the Ic lightcurve, where the emission from the M giant dominates, with a lightcurve strongly reminiscent of an ellipsoidal distortion plus irradiation from the hot companion. Pros and cons of 1860 and 331 days as the system orbital period are reviewed, waiting for a spectroscopic radial velocity orbit of the M giant to settle the question (provided the orbit is not oriented face-on).
2277. MW Lyr BV(RI)c light curves
ID:
ivo://CDS.VizieR/J/MNRAS/391/164
Title:
MW Lyr BV(RI)c light curves
Short Name:
J/MNRAS/391/164
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have obtained the most extensive and most accurate photometric data of a Blazhko variable MW Lyrae (MW Lyr) during the 2006-2007 observing seasons. The data within each 0.05 phase bin of the modulation period (P_m_=1/f_m_) cover the entire light cycle of the primary pulsation period (P_0_=1/f_0_) , making possible a very rigorous and complete analysis.
2278. MY Cyg differential light curves
ID:
ivo://CDS.VizieR/J/AJ/137/2949
Title:
MY Cyg differential light curves
Short Name:
J/AJ/137/2949
Date:
21 Oct 2021
Publisher:
CDS
Description:
Differential UBV photoelectric photometry for the eclipsing binary MY Cyg is presented. The Wilson-Devinney program is used to simultaneously solve the three light curves together with previously published radial velocities. A comparison is made with the previous solution found with the Russell-Merrill method. We examine the long-term apsidal motion of this well-detached, slightly eccentric system. We determine absolute dimensions, discuss metallicity/Am-star issues, and estimate the evolutionary status of the stars.
2279. M31Y eclipsing binaries and Cepheids
ID:
ivo://CDS.VizieR/J/AJ/126/175
Title:
M31Y eclipsing binaries and Cepheids
Short Name:
J/AJ/126/175
Date:
21 Oct 2021
Publisher:
CDS
Description:
The DIRECT Project aims to obtain direct distances to two Local Group galaxies, M31 and M33, which occupy a crucial position near the base of the cosmological distance ladder. The first step is to search for detached eclipsing binaries (DEBs) and Cepheids using 1m class telescopes to select good candidates, which will be followed up spectroscopically on 6.510m class telescopes. In this ninth paper, we present a catalog of variable stars discovered with image subtraction in field M31Y (RA=10.97{deg}, DE=41.69{deg}; J2000.0). The data were obtained with the Fred Lawrence Whipple Observatory 1.2m telescope on 25 nights, over a period of 6 months. In our search covering 22x22, we discovered 41 eclipsing binaries, 126 Cepheids, and 97 other periodic or nonperiodic variables, including a luminous blue variable candidate, a nova, and a Galactic cataclysmic variable. The catalog of variables, as well as their photometry and finding charts, is available electronically via anonymous ftp and the World Wide Web, at http://cfa-www.harvard.edu/~kstanek/DIRECT . The complete set of the CCD frames is available upon request.
2280. Nainital-Cape Survey. IV.
ID:
ivo://CDS.VizieR/J/A+A/590/A116
Title:
Nainital-Cape Survey. IV.
Short Name:
J/A+A/590/A116
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Nainital-Cape Survey is a dedicated ongoing Survey programme to search for and study pulsational variability in chemically peculiar (CP) stars to understand their internal structure and evolution. The main aims of this Survey are to find new pulsating Ap and Am stars in the northern and southern hemisphere and to perform asteroseismic studies of these new pulsators. The Survey is conducted using high-speed photometry. The candidate stars were selected on the basis of having Stromgren photometric indices similar to those of known pulsating CP stars. Over the last decade a total of 337 candidate pulsating CP stars were observed for the Nainital-Cape Survey, making it one of the longest ground-based surveys for pulsation in CP stars in terms of time span and sample size. The previous papers of this series presented seven new pulsating variables and 229 null results. In this paper we present the light curves, frequency spectra and various astrophysical parameters of the 108 additional CP stars observed since the last reported results. We also tabulated the basic physical parameters of the known roAp stars. As a part of establishing the detection limits in the Nainital-Cape Survey, we investigated the scintillation noise level at the two observing sites used in this Survey, Sutherland and Nainital, by comparing the combined frequency spectra stars observed from each location. Our analysis shows that both the sites permit the detection of variations of the order of 0.6-milli-magnitude (mmag) in the frequency range 1-4mHz, Sutherland is on average marginally better.