Search Publications
Speckle Interferometry at SOAR in 2022
Tokovinin, Andrei; Mason, Brian D.; Mendez, Rene A. +1 more
Results of the speckle-interferometry observations at the 4.1 m SOuthern Astrophysical Research Telescope obtained during 2022 are presented: 2508 measurements of 1925 resolved pairs or subsystems and 785 nonresolutions of 611 targets; 26 pairs are resolved here for the first time. This work continues our long-term effort to monitor orbital motion…
Independent Validation of the Temperate Super-Earth HD 79211 b using HARPS-N
López-Morales, Mercedes; Bieryla, Allyson; Stassun, Keivan G. +28 more
We present high-precision radial velocities (RVs) from the HARPS-N spectrograph for HD 79210 and HD 79211, two M0V members of a gravitationally bound binary system. We detect a planet candidate with a period of ${24.421}_{-0.017}^{+0.016}$ days around HD 79211 in these HARPS-N RVs, validating the planet candidate originally identified in CARMENES …
Detecting Solar System Analogs through Joint Radial Velocity/Astrometric Surveys
Angus, Ruth; Foreman-Mackey, Daniel; Spergel, David N. +1 more
Earth-mass exoplanets on year-long orbits and cool gas giants (CGG) on decade-long orbits lie at the edge of current detection limits. The Terra Hunting Experiment (THE) will take nightly radial velocity (RV) observations on HARPS3 of at least 40 bright nearby G and K dwarfs for 10 yr, with a target 1σ measurement error of ~0.3 m s-1, i…
SOFIA FEEDBACK Survey: The Pillars of Creation in [C II] and Molecular Lines
Wyrowski, Friedrich; Tiwari, Maitraiyee; Güsten, Rolf +11 more
We investigate the physical structure and conditions of photodissociation regions (PDRs) and molecular gas within the Pillars of Creation in the Eagle Nebula using SOFIA FEEDBACK observations of the [C II] 158 µm line. These observations are velocity resolved to 0.5 km s-1 and are analyzed alongside a collection of complimentary d…
HST/WFC3 Light Curve Supports a Terrestrial Composition for the Closest Exoplanet to Transit an M Dwarf
Winters, Jennifer G.; Eastman, Jason D.; Bean, Jacob L. +6 more
Previous studies of the exoplanet LTT 1445Ac concluded that the light curve from the Transiting Exoplanet Survey Satellite (TESS) was consistent with both grazing and nongrazing geometries. As a result, the radius and hence density of the planet remained unknown. To resolve this ambiguity, we observed the LTT 1445 system for six spacecraft orbits …
A Search for Technosignatures Around 11,680 Stars with the Green Bank Telescope at 1.15-1.73 GHz
Margot, Jean-Luc; Lynch, Ryan S.; Chen, James +77 more
We conducted a search for narrowband radio signals over four observing sessions in 2020-2023 with the L-band receiver (1.15-1.73 GHz) of the 100 m diameter Green Bank Telescope. We pointed the telescope in the directions of 62 TESS Objects of Interest, capturing radio emissions from a total of ~11,680 stars and planetary systems in the ~9' beam of…
Surrounded by Giants: Habitable Zone Stability Within the HD 141399 System
Kane, Stephen R.
The search for exoplanets has revealed a diversity of planetary system architectures, the vast majority of which diverge significantly from the template of the solar system. In particular, giant planets beyond the snow line are relatively rare, especially for low-mass stars, placing the solar system within a small category of systems with multiple…
Comparative Study of TESS Photometry and Radial Velocities on Six Early K-type Contact Binaries with Similar Periods around 0.268 Day
Huang, Y.; Qian, S. -B.; Liao, W. -P. +2 more
High-precision light curves were extracted from TESScut images. Together with APOGEE and LAMOST medium-resolution spectra, a joint study was made for six early K-type contact binary candidates selected unbiasedly with orbital periods around 0.268 day. It is found that all of them (RV CVn, EK Com, V384 Ser, V1038 Her, EH CVn, and CSS_J125403.7+5039…
Contemporaneous Observations of Hα Luminosities and Photometric Amplitudes for M Dwarfs
Kesseli, Aurora Y.; Douglas, Stephanie T.; Newton, Elisabeth R. +2 more
While many M dwarfs are known to have strong magnetic fields and high levels of magnetic activity, we are still unsure about the properties of their starspots and the origin of their magnetic dynamos. Both starspots and chromospheric heating are generated by the surface magnetic field; they produce photometric variability and Hα emission, respecti…
Long-term 4.6 µm Variability in Brown Dwarfs and a New Technique for Identifying Brown Dwarf Binary Candidates
Meisner, Aaron M.; Kirkpatrick, J. Davy; Gelino, Christopher R. +9 more
Using a sample of 361 nearby brown dwarfs, we have searched for 4.6 µm variability, indicative of large-scale rotational modulations or large-scale, long-term changes on timescales of over 10 yr. Our findings show no statistically significant variability in Spitzer's Infrared Array Camera (IRAC) channel 2 (ch2) or Wide-field Infrared Survey …