- ID:
- ivo://CDS.VizieR/J/PASP/121/1188
- Title:
- Periodic variables in NGC 2301
- Short Name:
- J/PASP/121/1188
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a search for periodic variables within 4078 time-series light curves and an analysis of the period-color plane for stars in the field of the open cluster NGC 2301. One hundred thirty-eight periodic variables were discovered, of which five are eclipsing binary candidates with unequal minima. The remaining 133 periodic variables appear to consist mainly of late-type stars whose variation is due to rotation modulated by star spot activity. The determined periods range from less than a day to over 14 days and have nearly unreddened B-R colors in the range of 0.8 to 2.8. The Barnes (2003ApJ...586..464B) interpretation of the period-color plane of late type stars is tested with our data. Our data did not show distinct I and C sequences, likely due to nonmember field stars contaminating in the background, as we estimate the total contamination to be 43%. Using different assumptions, the gyrochronological age of the cluster is calculated to be 210+/-25Myr, which falls in the range of age values (164-250Myr) determined by previous studies. Finally, we present evidence which nullifies the earlier suggestion that two of the variable stars in NGC 2301 might be white dwarfs.
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Search Results
- ID:
- ivo://CDS.VizieR/J/AJ/135/1459
- Title:
- Period of M15 variable stars
- Short Name:
- J/AJ/135/1459
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new BVI CCD photometry for variables in the globular cluster M15. Our photometry was obtained using both the image subtraction package ISIS and DAOPHOT/ALLFRAME. The data were acquired in 2001 on two observing runs on 11 observing nights using the 2m telescope of the Bulgarian National Astronomical Observatory "Rozhen" with a Photometrics CCD camera. For 39 previously known variables, we present a period for the first time, and improved periods were obtained for many previously known variables. Fourteen new variables are reported. We present updated Bailey diagrams for the cluster, and discuss its Oosterhoff classification. Although many of M15's RRab pulsators fall at an intermediate locus between Oosterhoff types I and II (OoII) in the Bailey diagram, we argue that M15 is indeed a bona fide OoII globular cluster.
703. PESSTO catalog
- ID:
- ivo://CDS.VizieR/J/A+A/579/A40
- Title:
- PESSTO catalog
- Short Name:
- J/A+A/579/A40
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Public European Southern Observatory Spectroscopic Survey of Transient Objects (PESSTO) began as a public spectroscopic survey in April 2012. PESSTO classifies transients from publicly available sources and wide-field surveys, and selects science targets for detailed spectroscopic and photometric follow-up. PESSTO runs for nine months of the year, January - April and August - December inclusive, and typically has allocations of 10 nights per month. We describe the data reduction strategy and data products that are publicly available through the ESO archive as the Spectroscopic Survey data release 1 (SSDR1). PESSTO uses the New Technology Telescope with the instruments EFOSC2 and SOFI to provide optical and NIR spectroscopy and imaging. We target supernovae and optical transients brighter than 20.5^m^ for classification. Science targets are selected for follow-up based on the PESSTO science goal of extending knowledge of the extremes of the supernova population. We use standard EFOSC2 set-ups providing spectra with resolutions of 13-18{AA} between 3345-9995{AA}. A subset of the brighter science targets are selected for SOFI spectroscopy with the blue and red grisms (0.935-2.53{mu}m and resolutions 23-33{AA}) and imaging with broadband JHK_s_ filters. This first data release (SSDR1) contains flux calibrated spectra from the first year (April 2012-2013). A total of 221 confirmed supernovae were classified, and we released calibrated optical spectra and classifications publicly within 24h of the data being taken (via WISeREP). The data in SSDR1 replace those released spectra. They have more reliable and quantifiable flux calibrations, correction for telluric absorption, and are made available in standard ESO Phase 3 formats. We estimate the absolute accuracy of the flux calibrations for EFOSC2 across the whole survey in SSDR1 to be typically ~15%, although a number of spectra will have less reliable absolute flux calibration because of weather and slit losses. Acquisition images for each spectrum are available which, in principle, can allow the user to refine the absolute flux calibration. The standard NIR reduction process does not produce high accuracy absolute spectrophotometry but synthetic photometry with accompanying JHK_s_ imaging can improve this. Whenever possible, reduced SOFI images are provided to allow this. Future data releases will focus on improving the automated flux calibration of the data products. The rapid turnaround between discovery and classification and access to reliable pipeline processed data products has allowed early science papers in the first few months of the survey.
- ID:
- ivo://CDS.VizieR/J/ApJS/155/1
- Title:
- Phoenix Deep Survey: optical and NIR catalogs
- Short Name:
- J/ApJS/155/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Phoenix Deep Survey is a multiwavelength galaxy survey based on deep 1.4GHz radio imaging. The primary goal of this survey is to investigate the properties of star formation in galaxies and to trace the evolution in those properties to a redshift z=1, covering a significant fraction of the age of the universe. By compiling a sample of star-forming galaxies based on selection at radio wavelengths we eliminate possible biases due to dust obscuration, a significant issue when selecting objects at optical and ultraviolet wavelengths. In this paper, we present the catalogs and results of deep optical (UBVRI) and near-infrared (Ks) imaging of the deepest region of the existing decimetric radio imaging. The observations and data processing are summarized and the construction of the optical source catalogs described, together with the details of the identification of candidate optical counterparts to the radio catalogs. Based on our UBVRIKs imaging, photometric redshift estimates for the optical counterparts to the radio detections are explored.
- ID:
- ivo://CDS.VizieR/II/120
- Title:
- Phot and Spectrophot Investigation, South Gal Pole
- Short Name:
- II/120
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Photoelectric magnitudes and colors in the Johnson-Morgan UBV system for 477 stars in 6 square degrees near Kapteyn Selected Area 141 (l=245, b=-86; 00 43 < RA < 01 11, -33.7 < Dec < -26.9, B1950.0) are given in the first data file. The estimated rms accuracies are 0.02 (V), 0.03 (B-V), 0.07 (U-B) for stars in the magnitude range 15 to 16. Table 2 of the source reference gives the mean errors for intervals of magnitude. Photographic V magnitudes and B-V colors are given for 2835 stars to magnitude 17 (in the same region as above) in the second data file. The estimated rms accuracies are 0.05 (V) and 0.08 (B-V). The mean errors of the computed right ascensions and declinations are 0.15s and 2", respectively.
- ID:
- ivo://CDS.VizieR/II/27
- Title:
- Photoelectric measurements in UcBV system
- Short Name:
- II/27
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- All measurements in the literature on the Cape photometric system as of early 1975 have been compiled. The catalog includes measurements from 38 publications as well as 469 unpublished measurements forwarded by Dr. A. W. J. Cousins.
- ID:
- ivo://CDS.VizieR/II/217
- Title:
- Photoelectric observations of Cepheids in UBV(RI)c
- Short Name:
- II/217
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Observations are listed in alphabetical order of the constellations. The standard deviation for every magnitude and color is 0.01 mag.
- ID:
- ivo://CDS.VizieR/II/285
- Title:
- Photoelectric observations of Cepheids in UBV(RI)c
- Short Name:
- II/285
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalog gathers the observation of 894 Cepheids made between 1986 to 2004. Observations are listed in alphabetical order of the constellations. The standard deviation for every magnitude and color is 0.01mag. This version supersedes the 1997 edition (Cat. <II/217>)
- 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.
- 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.
