Search Publications
Disk or Companion: Characterizing Excess Infrared Flux in Seven White Dwarf Systems with Near-infrared Spectroscopy
Zuckerman, B.; Manjavacas, Elena; Dufour, Patrick +7 more
Excess infrared flux from white dwarf stars is likely to arise from a dusty debris disk or a cool companion. In this work, we present near-infrared spectroscopic observations with Keck/MOSFIRE, Gemini/GNIRS, and Gemini/Flamingos-2 of seven white dwarfs with infrared excesses identified in previous studies. We confirmed the presence of dust disks a…
Revisiting the Transit Timing and Atmosphere Characterization of the Neptune-mass Planet HAT-P-26 b
McDonald, Iain; Dhillon, Vik S.; A-thano, Napaporn +11 more
We present a transit-timing variation (TTV) and planetary atmosphere analysis of the Neptune-mass planet HAT-P-26 b. We present a new set of 13 transit light curves from optical ground-based observations and combine them with light curves from the Wide Field Camera 3 on the Hubble Space Telescope, the Transiting Exoplanet Survey Satellite, and pre…
Weighing the Darkness. II. Astrometric Measurement of Partial Orbits with Gaia
Breivik, Katelyn; Andrews, Jeff J.; Chawla, Chirag +2 more
Over the course of several years, stars trace helical trajectories as they traverse across the sky due to the combined effects of proper motion and parallax. It is well known that the gravitational pull of an unseen companion can cause deviations to these tracks. Several studies have pointed out that the astrometric mission Gaia will be able to id…
First BISTRO Observations of the Dark Cloud Taurus L1495A-B10: The Role of the Magnetic Field in the Earliest Stages of Low-mass Star Formation
Zhang, Yapeng; Pattle, Kate; Karoly, Janik +155 more
We present BISTRO Survey 850 µm dust emission polarization observations of the L1495A-B10 region of the Taurus molecular cloud, taken at the James Clerk Maxwell Telescope (JCMT). We observe a roughly triangular network of dense filaments. We detect nine of the dense starless cores embedded within these filaments in polarization, finding that…
The Subtle Effects of Mergers on Star Formation in Nearby Galaxies
Ho, Luis C.; Shangguan, Jinyi; Li, Yang A.
Interactions and mergers play an important role in regulating the physical properties of galaxies, such as their morphology, gas content, and star formation rate (SFR). Controversy exists as to the degree to which these events, even gas-rich major mergers, enhance star formation activity. We study merger pairs selected from a sample of massive (M …
First Infrared Coronal Spectra from DKIST/Cryo-NIRSP: Comparisons with Global MHD Models
Tritschler, Alexandra; Schad, Thomas A.; Kuhn, Jeffrey R. +4 more
The Cryogenic Near-Infrared Spectropolarimeter (Cryo-NIRSP) is now conducting science operations at the National Science Foundation's Daniel K. Inouye Solar Telescope (DKIST). We report results obtained during instrument commissioning that advance multiwavelength coronagraphic observations in the infrared. This includes the first observations of t…
The value-added catalogue of ASAS-SN eclipsing binaries - III. Masses and radii of Gaia spectroscopic binaries
Kochanek, C. S.; Stanek, K. Z.; Thompson, Todd A. +4 more
Masses and radii of stars can be derived by combining eclipsing binary light curves with spectroscopic orbits. In our previous work, we modelled the All-Sky Automated Survey for Supernovae (ASAS-SN) light curves of more than 30 000 detached eclipsing binaries using PHOEBE. Here, we combine our results with 128 double-lined spectroscopic orbits fro…
A large topographic feature on the surface of the trans-Neptunian object (307261) 2002 MS4 measured from stellar occultations
Barnes, J. W.; Burwitz, V.; Hueso, R. +201 more
Context. The physical characterization of trans-Neptunian objects is essential for improving our understanding of the formation and evolution of our Solar System. Stellar occultation is a ground-based technique that can be successfully used to determine some of the TNOs' fundamental physical properties with high precision, such as size and shape. …
Reanalysis of neutron-capture elements in the benchmark r-rich star CS 31082-001
Spite, M.; Evans, C. J.; Barbuy, B. +4 more
We revisit the abundances of neutron-capture elements in the metal-poor ([Fe/H] = -2.9) r-process-rich halo star CS 31082-001. Partly motivated by the development of the new near-ultraviolet Cassegrain U-band Efficient Spectrograph for the Very Large Telescope, we compiled an expanded line list for heavy elements over the range 3000-4000 Å, includ…
The chemical compositions of multiple stellar populations in the globular cluster NGC 2808
Milone, A. P.; Cordoni, G.; Marino, A. F. +8 more
Pseudo two-colour diagrams or Chromosome maps (ChM) indicate that NGC 2808 host five different stellar populations. The existing ChMs have been derived by the Hubble Space Telescope photometry, and comprise of stars in a small field of view around the cluster centre. To overcome these limitations, we built a ChM with U, B, I photometry from ground…