Search Publications
Short-period Variables in TESS Full-frame Image Light Curves Identified via Convolutional Neural Networks
Powell, Brian P.; Barclay, Thomas; Kruse, Ethan +9 more
The Transiting Exoplanet Survey Satellite (TESS) mission measured light from stars in ∼85% of the sky throughout its 2 yr primary mission, resulting in millions of TESS 30-minute-cadence light curves to analyze in the search for transiting exoplanets. To search this vast data set, we aim to provide an approach that is computationally efficient, pr…
Atmospheric parameters and chemical abundances within 100 pc: a sample of G, K, and M main-sequence stars
Stassun, Keivan G.; Kounkel, Marina; Lane, Richard R. +9 more
To date, we have access to enormous inventories of stellar spectra that allow the extraction of atmospheric parameters and chemical abundances essential in stellar studies. However, characterizing such a large amount of data is complex and requires a good understanding of the studied object to ensure reliable and homogeneous results. In this study…
Predicting the Arrival Time of an Interplanetary Shock Based on DSRT Spectrum Observations for the Corresponding Type II Radio Burst and a Blast Wave Theory
Feng, Shiwei; Ruan, Mengsi; Li, Ran +7 more
Since fast head-on coronal mass ejections and their associated shocks represent potential hazards to the space environment of the Earth and even other planets, forecasting the arrival time of the corresponding interplanetary shock is a priority in space weather research and prediction. Based on the radio spectrum observations of the 16-element arr…
The Empirical and Radiative Transfer Hybrid (EaRTH) Disk Model: Merging Analyses of Protoplanetary Dust Disk Mineralogy and Structure
Stassun, Keivan G.; Pinte, Christophe; Principe, David A. +7 more
Our understanding of how exoplanets form and evolve relies on analyses of both the mineralogy of protoplanetary disks and their detailed structures; however, these key complementary aspects of disks are usually studied separately. We present initial results from a hybrid model that combines the empirical characterization of the mineralogy of a dis…
Crimson Behemoth: A massive clumpy structure hosting a dusty AGN at z=4.91
Casey, Caitlin M.; Kartaltepe, Jeyhan S.; Koekemoer, Anton M. +40 more
The current paradigm for the co-evolution of galaxies and their supermassive black holes postulates that dust-obscured active galactic nuclei (AGNs) represent a transitional phase towards a more luminous and unobscured state. However, our understanding of dusty AGNs and their host galaxies at early cosmic times is inadequate due to observational l…
The Age Distribution of Stellar Orbit Space Clumps
Rix, Hans-Walter; Fürnkranz, Verena; Coronado, Johanna +1 more
The orbit distribution of young stars in the Galactic disk is highly structured, from well-defined clusters to streams of stars that may be widely dispersed across the sky, but are compact in orbital action-angle space. The age distribution of such groups can constrain the timescales over which conatal groups of stars disperse into the "field." Ga…
Study of star formation in dual nuclei galaxies using UVIT observations
Kharb, P.; Das, M.; Rahna, P. T. +3 more
We have used the Ultraviolet Imaging Telescope (UVIT) aboard AstroSat to study star formation in a sample of nine dual nuclei galaxies with separations ⪅ 11 kpc, which is an expected outcome of galaxy mergers. To minimize the contribution of active galactic nuclei (AGN) emission, we have used mid-IR colour cut-offs and masked the AGN-dominated nuc…
Can we constrain structure growth from galaxy proper motions?
Alonso, David; Slosar, Anže; Storey-Fisher, Kate +1 more
Galaxy peculiar velocities can be used to trace the growth of structure on cosmological scales. In the radial direction, peculiar velocities cause redshift space distortions, an established cosmological probe, and can be measured individually in the presence of an independent distance indicator. In the transverse direction, peculiar velocities cau…
12C/13C of Kepler giant stars: The missing piece of the mixing puzzle
Reylé, C.; Lagarde, N.; Miglio, A. +6 more
Context. Despite a rich observational background, few spectroscopic studies have dealt with the measurement of the carbon isotopic ratio in giant stars. However, it is a key element in understanding the mixing mechanisms that occur in the interiors of giant stars.
Aims: We present the CNO and 12C/13C abundances derived f…
Age Analysis of Extrasolar Planets: Insight from Stellar Isochrone Models
Narang, Mayank; Swastik, C.; Banyal, Ravinder K. +2 more
There is growing evidence from stellar kinematics and galactic chemical evolution suggesting that giant planets (M P ≥ 0.3M J ) are relatively young compared to the most commonly occurring population of small planets (M P < 0.3M J ). To further test the validity of these results, we analyzed the…