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.
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.
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%.
This data collection contains fits (both good and bad) that were
found during R. J. Wilson et al's grant from NASA's Cassini Data
Analysis Program (NNX12AG90G).
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.
Cassini-Huygens Plasma Spectrometer (CAPS) Calibrated Electron
Spectrometer Data Collection
Short Name:
cassini_caps_cal
Date:
25 Apr 2025 02:00:17
Publisher:
Planetary Data System
Description:
This collection consists of all of the calibrated electron
spectrometer data from the Cassini Plasma Spectrometer (CAPS) on-board
the Cassini spacecraft during the entire Cassini mission.
Cassini-Huygens Plasma Spectrometer (CAPS) Calibrated Ion Beam
Spectrometer Data Collection
Short Name:
cassini_caps_cal
Date:
25 Apr 2025 02:02:02
Publisher:
Planetary Data System
Description:
This collection consists of all of the calibrated ion beam
spectrometer data from the Cassini Plasma Spectrometer (CAPS) on-board
the Cassini spacecraft during the entire Cassini mission.
Cassini-Huygens Plasma Spectrometer (CAPS) Calibrated Ion Mass
Spectrometer Ion Data Collection
Short Name:
cassini_caps_cal
Date:
25 Apr 2025 01:58:05
Publisher:
Planetary Data System
Description:
This collection consists of all of the calibrated Ion Mass
Spectrometer ion data from the Cassini Plasma Spectrometer (CAPS)
on-board the Cassini spacecraft during the entire Cassini mission.
