- ID:
- ivo://CDS.VizieR/J/AJ/109/2376
- Title:
- Case blue/emission-line galaxies
- Short Name:
- J/AJ/109/2376
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present CCD imaging and spectroscopic data for 176 blue and/or emission-line galaxies from Lists I and II of the Case Northern Sky Survey. Our sample consists of all Case galaxies which lie in the region which overlaps the original Slice of the Universe survey. We use the observational data to investigate the physical properties of the galaxies selected by the surveys to compare with various parameters published in the survey lists, and to investigate the selection characteristics and completeness limit of the survey. The majority of the Case galaxies are energized by regions of active star formation; only 5% of the sample are Seyfert galaxies. The dual selection techniques used (both UV-excess and emission lines) allow the survey to detect star-forming galaxies with a wide range of properties and evolutionary states. In particular, the Case survey selects galaxies with lower levels of activity than most previous surveys. The survey also includes a larger fraction of intermediate and low-luminosity galaxies than would be present in a purely magnitude-limited sample. Although galaxies as faint as m_B_=19 are present in the sample, the completeness limit of the UV-excess selected portion of the survey is closer to m_B_=16. The luminosity function of the Case galaxies is derived and compared with that of the "normal" field galaxies in the same volume of space. The shape of the Case luminosity function is similar to that for the field sample. A surprising result is that 31% of the field galaxy population can be accounted for by galaxies of the type selected in the Case survey.
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Search Results
- ID:
- ivo://CDS.VizieR/J/ApJS/66/309
- Title:
- Case low-dispersion Survey VI
- Short Name:
- J/ApJS/66/309
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Positions, estimated magnitudes, and finding charts (when needed) are provided for 183 A-F stars (including both Population I and horizontal-branch stars) contained within the region 12h00m <R.A> <13h00m and +29.0 <decl. <+34.0. These stars, whose blue magnitudes range from 5.5 to 17.5, were identified on low-dispersion, objective-prism plates taken with the Burrell Schmidt telescope.
- ID:
- ivo://CDS.VizieR/J/ApJS/66/387
- Title:
- Case low-dispersion Survey VII.
- Short Name:
- J/ApJS/66/387
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Observational data on 132 faint (R magnitude = 9-17) red stars with carbon-star or late M-type spectra are presented in tables and briefly characterized. The data were collected in a survey of a 1000-sq deg region at high northern Galactic latitude (right ascension 8h15 to 17h30 and declination +29 to +38 deg) on low-dispersion 330-535-nm objective-prism plates obtained with the 61/91-cm Burrell Schmidt telescope at Kitt Peak Observatory.
- ID:
- ivo://CDS.VizieR/J/ApJS/71/549
- Title:
- Case low-dispersion Survey X.
- Short Name:
- J/ApJS/71/549
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Position, estimated magnitudes, and finding charts are provided for 540 A-F stars in the region 8h00m <R.A< 11h10m and +29.0 <Decl.<+43.0 (1950). The Galactic latitudes lie within the range +27 and +68. The A-F stars, with blue magnitudes between 14 and 17, were identified on low-dispersion objective-prism plates taken with the Burell Schmidt telescope. A large fraction of these A-F stars are expected to belong to Population II.
- ID:
- ivo://CDS.VizieR/J/AJ/145/43
- Title:
- CASE. V. Three eclipsing binaries in M4
- Short Name:
- J/AJ/145/43
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use photometric and spectroscopic observations of the eclipsing binaries V65, V66, and V69 in the field of the globular cluster M4 to derive masses, radii, and luminosities of their components. The orbital periods of these systems are 2.29, 8.11, and 48.19days, respectively. The measured masses of the primary and secondary components (M_p_ and M_s_) are 0.8035+/-0.0086 and 0.6050+/-0.0044M_{sun}_ for V65, 0.7842+/-0.0045 and 0.7443+/-0.0042M_{sun}_ for V66, and 0.7665+/-0.0053 and 0.7278+/-0/0048M_{sun}_ for V69. The measured radii (R_p_ and R_s_) are 1.147+/-0.010 and 0.6110 +/- 0.0092R_{sun}_ for V66, 0.9347+/-0.0048 and 0.8298+/-0.0053R_{sun}_ for V66, and 0.8655+/-0.0097 and 0.8074+/-0.0080R_{sun}_ for V69. The orbits of V65 and V66 are circular, whereas that of V69 has an eccentricity of 0.38. Based on systemic velocities and relative proper motions, we show that all three systems are members of the cluster. We find that the distance to M4 is 1.82+/-0.04kpc-in good agreement with recent estimates based on entirely different methods. We compare the absolute parameters of V66 and V69 with two sets of theoretical isochrones in mass-radius and mass-luminosity diagrams, and for assumed [Fe/H]=-1.20, [{alpha}/Fe]=0.4, and Y=0.25 we find the most probable age of M4 to be between 11.2 and 11.3Gyr. Color-magnitude diagram (CMD) fitting with the same parameters yields an age close to, or slightly in excess of, 12Gyr. However, considering the sources of uncertainty involved in CMD fitting, these two methods of age determination are not discrepant. Age and distance determinations can be further improved when infrared eclipse photometry is obtained.
- ID:
- ivo://CDS.VizieR/J/ApJ/742/54
- Title:
- CASH project II. 14 extremely metal-poor stars
- Short Name:
- J/ApJ/742/54
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a comprehensive abundance analysis of 20 elements for 16 new low-metallicity stars from the Chemical Abundances of Stars in the Halo (CASH) project. The abundances have been derived from both Hobby-Eberly Telescope High Resolution Spectrograph snapshot spectra (R~15000) and corresponding high-resolution (R~35000) Magellan Inamori Kyocera Echelle spectra. The stars span a metallicity range from [Fe/H] from -2.9 to -3.9, including four new stars with [Fe/H]<-3.7. We find four stars to be carbon-enhanced metal-poor (CEMP) stars, confirming the trend of increasing [C/Fe] abundance ratios with decreasing metallicity. Two of these objects can be classified as CEMP-no stars, adding to the growing number of these objects at [Fe/H]<-3. We also find four neutron-capture-enhanced stars in the sample, one of which has [Eu/Fe] of 0.8 with clear r-process signatures. These pilot sample stars are the most metal-poor ([Fe/H]<~-3.0) of the brightest stars included in CASH and are used to calibrate a newly developed, automated stellar parameter and abundance determination pipeline. This code will be used for the entire ~500 star CASH snapshot sample. We find that the pipeline results are statistically identical for snapshot spectra when compared to a traditional, manual analysis from a high-resolution spectrum.
- ID:
- ivo://CDS.VizieR/J/ApJ/814/121
- Title:
- CASH project. III. The CEMP star HE0414-0343
- Short Name:
- J/ApJ/814/121
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a detailed abundance analysis of 23 elements for a newly discovered carbon-enhanced metal-poor (CEMP) star, HE0414-0343, from the Chemical Abundances of Stars in the Halo Project. Its spectroscopic stellar parameters are T_eff_=4863K, logg=1.25, {xi}=2.20km/s, and [Fe/H]=-2.24. Radial velocity measurements covering seven years indicate HE 0414-0343 to be a binary. HE0414-0343 has [C/Fe]=1.44 and is strongly enhanced in neutron-capture elements but its abundances cannot be reproduced by a solar-type s-process pattern alone. Traditionally, it could be classified as a "CEMP-r/s" star. Based on abundance comparisons with asymptotic giant branch (AGB) star nucleosynthesis models, we suggest a new physically motivated origin and classification scheme for CEMP-s stars and the still poorly understood CEMP-r/s. The new scheme describes a continuous transition between these two so-far distinctly treated subgroups: CEMP-sA, CEMP-sB, and CEMP-sC. Possible causes for a continuous transition include the number of thermal pulses the AGB companion underwent, the effect of different AGB star masses on their nucleosynthetic yields, and physics that is not well approximated in 1D stellar models such as proton ingestion episodes and rotation. Based on a set of detailed AGB models, we suggest the abundance signature of HE 0414-0343 to have arisen from a >1.3M_{sun}_ mass AGB star and a late-time mass transfer that transformed HE 0414-0343 into a CEMP-sC star. We also find that the [Y/Ba] ratio well parametrizes the classification and can thus be used to easily classify any future such stars.
- ID:
- ivo://CDS.VizieR/J/ApJ/659/162
- Title:
- CAS parameters of 199 nearby galaxies
- Short Name:
- J/ApJ/659/162
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a quantitative analysis of the morphologies for 199 nearby galaxies as parameterized with measurements of the concentration, asymmetry, and clumpiness (CAS) parameters at wavelengths from 0.15 to 0.85um. We find that these CAS parameters depend on both galaxy type and the wavelength of observation. As such, we use them to obtain a quantitative measure of the "morphological k-correction", i.e., the change in appearance of a galaxy with rest-frame wavelength.
- ID:
- ivo://CDS.VizieR/J/A+A/620/A127
- Title:
- Cassification of RR Lyrae and Cepheid
- Short Name:
- J/A+A/620/A127
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The second data release of the Gaia mission (DR2) includes an advance catalogue of variable stars. The classifications of these stars are based on sparse photometry from the first 22 months of the mission. We set out to investigate the purity and completeness of the all-sky Gaia classification results with the help of the continuous light curves of the observed targets from the Kepler and K2 missions, focusing specifically on RR Lyrae and Cepheid pulsators, outside the Galactic bulge region. We cross-matched the Gaia identifications with the observations collected by the Kepler space telescope. We inspected the light curves visually, then calculated the relative Fourier coefficients and period ratios for the single- and double-mode K2 RR Lyrae stars to further classify them. We identified 1443 and 41 stars classified as RR Lyrae or Cepheid variables in Gaia DR2 in the targeted observations of the two missions and 263 more RR Lyre targets in the full-frame images (FFI) of the original mission. We provide the cross-match of these sources. We conclude that the RR Lyrae catalogue has a completeness between 70-78%, and provide a purity estimate of between 92-98% (targeted observations) with lower limits of 75% (FFI stars) and 51% (K2 worst-case scenario). The low number of Cepheids prevents us from drawing detailed conclusions, but the purity of the DR2 sample is estimated to be about 66%.
- ID:
- ivo://CDS.VizieR/J/ApJS/244/14
- Title:
- Cassini CIRS observations of Titan 2004-2017
- Short Name:
- J/ApJS/244/14
- Date:
- 28 Dec 2021 09:28:19
- Publisher:
- CDS
- Description:
- From 2004 to 2017, the Cassini spacecraft orbited Saturn, completing 127 close flybys of its largest moon, Titan. Cassini's Composite Infrared Spectrometer (CIRS), one of 12 instruments carried on board, profiled Titan in the thermal infrared (7-1000{mu}m) throughout the entire 13yr mission. CIRS observed on both targeted encounters (flybys) and more distant opportunities, collecting 8.4 million spectra from 837 individual Titan observations over 3633hr. Observations of multiple types were made throughout the mission, building up a vast mosaic picture of Titan's atmospheric state across spatial and temporal domains. This paper provides a guide to these observations, describing each type and chronicling its occurrences and global-seasonal coverage. The purpose is to provide a resource for future users of the CIRS data set, as well as those seeking to put existing CIRS publications into the overall context of the mission, and to facilitate future intercomparison of CIRS results with those of other Cassini instruments and ground-based observations.
