Search Publications
Small and Close-in Planets are Uncommon Around A-type Stars
Giacalone, Steven; Dressing, Courtney D.
The Kepler and K2 missions enabled robust calculations of planet occurrence rates around FGKM-type stars. However, these missions observed too few stars with earlier spectral types to tightly constrain the occurrence rates of planets orbiting hotter stars. Using TESS, we calculate the occurrence rate of small (1 R⊕ < Rp &l…
Photometric Determination of Unresolved Main-sequence Binaries in the Pleiades: Binary Fraction and Mass-ratio Distribution
Li, Lu; Shao, Zhengyi; Liu, Rongrong
Accurate determination of binary fractions (fb) and mass ratio (q) distributions is crucial for understanding the dynamical evolution of open clusters. We present an improved multiband fitting technique to enhance the analysis of binary properties. This approach enables an accurate photometric determination of fb and q distri…
Unfolding X-Ray Spectral Data: Conditions and Applications
Huenemoerder, David P.; Gunderson, Sean J.
We present conditions for which X-ray spectra can be "unfolded" to present an accurate representation of the true source spectra. The method we use to unfold the data is implemented in the Interactive Spectral Interpretation Software and distinguishes itself as being model-independent. We find that this method of unfolding makes accurate represent…
Bioverse: Giant Magellan Telescope and Extremely Large Telescope Direct Imaging and High-resolution Spectroscopy Assessment—Surveying Exo-Earth O2 and Testing the Habitable Zone Oxygen Hypothesis
Wagner, Kevin; Apai, Dániel; Schlecker, Martin +4 more
Biosignature detection in the atmospheres of Earth-like exoplanets is one of the most significant and ambitious goals for astronomy, astrobiology, and humanity. Molecular oxygen is among the strongest indicators of life on Earth, but it will be extremely difficult to detect via transmission spectroscopy. We used the Bioverse statistical framework …
Quantifying the Contamination from nearby Stellar Companions in Gaia DR3 Photometry
Huber, Daniel; Berger, Travis A.; Kraus, Adam L. +1 more
Identifying and removing binary stars from stellar samples is a crucial but complicated task. Regardless of how carefully a sample is selected, some binaries will remain and complicate interpretation of results, especially via flux contamination of survey photometry. One such sample is the data from the Gaia spacecraft, which is collecting photome…
Astronomaly Protege: Discovery through Human-machine Collaboration
Rudnick, Lawrence; Lochner, Michelle
Modern telescopes generate catalogs of millions of objects with the potential for new scientific discoveries, but this is beyond what can be examined visually. Here we introduce ASTRONOMALY: PROTEGE, an extension of the general-purpose machine-learning-based active anomaly detection framework ASTRONOMALY. PROTEGE is designed to provide well-select…
Kinematics of Cataclysmic Variables in the Solar Neighborhood in the Gaia Era
Bilir, Selçuk; Canbay, Remziye; AK, Tansel +2 more
Using high-precision astrometric data from Gaia DR3 and updated systemic velocities from the literature, the kinematical properties of cataclysmic variables (CVs) were investigated. By constraining the data according to the total space velocity error and Galactic population class, a reliable sample of data was obtained. Nonmagnetic CVs located in …
Origins of Super Jupiters: TOI-2145b has a Moderately Eccentric and Nearly Aligned Orbit
Mahadevan, Suvrath; Zhou, George; Chontos, Ashley +15 more
Super Jupiters are giant planets with several Jupiter masses. It remains an open question whether these planets originate with such high masses or grow through collisions. Previous work demonstrates that warm super Jupiters tend to have more eccentric orbits compared to regular-mass warm Jupiters. This correlation between mass and eccentricity may…
The 10 pc Neighborhood of Habitable Zone Exoplanetary Systems: Threat Assessment from Stellar Encounters and Supernovae
Swastik, C.; Banyal, Ravinder K.; Pyne, Tisyagupta +1 more
The habitability of a planet is influenced by both its parent star and the properties of its local stellar neighborhood. Potential threats to habitability from the local stellar environment mainly arise from two factors: cataclysmic events such as powerful stellar explosions and orbital perturbations induced by close stellar encounters. Among the …
Analyses of Multiple Balmer Emission Lines from Accreting Brown Dwarfs and Very Low Mass Stars
Hashimoto, Jun; Aoyama, Yuhiko
A planetary growth rate, i.e., the mass accretion rate, is a fundamental parameter in planet formation, as it determines a planet's final mass. Planetary mass accretion rates have been estimated using hydrogen lines, based on the models originally developed for accreting stars, known as the accretion flow model. Recently, Aoyama et al. introduced …