Search Publications
X-Ray Emission from the Exoplanet Hosting LTT 1445 Triple Star System
Brown, Alexander; France, Kevin; Youngblood, Allison +5 more
JWST will be able to observe the atmospheres of rocky planets transiting nearby M dwarfs. The M-dwarf triple star system LTT 1445, at a distance of 6.86 pc, hosts some of the nearest rocky terrestrial planets. These planets most likely orbit the M 3.5V star LTT 1445A. During a 28.6 ks Chandra ACIS-S3 observation we have: (i) spatially resolved and…
Discovery of 34 Low-mass Comoving Systems Using NOIRLab Source Catalog DR2
Kiman, Rocio; Kirkpatrick, J. Davy; Burgasser, Adam J. +12 more
We present the discovery of 34 comoving systems containing an ultracool dwarf found by means of the NOIRLab Source Catalog (NSC) DR2. NSC's angular resolution of ~ 1″ allows for the detection of small separation binaries with significant proper motions. We used the catalog's accurate proper motion measurements to identify the companions by cross-m…
Ages and Masses of Star Clusters in M33: a Multiwavelength Study
Calzetti, Daniela; Moeller, Caitlin
We combine archival images for the nearby galaxy M33 (Triangulum Galaxy) from the ultraviolet (UV) to the infrared to derive ages, masses, and extinctions for the young star cluster population, and compare our physical parameters with published ones. Our goal is to test the robustness of clusters ages and masses, and possibly improve on existing o…
HD 83443c: A Highly Eccentric Giant Planet on a 22 yr Orbit
Kane, Stephen R.; Butler, R. P.; Wittenmyer, Robert A. +20 more
We report the discovery of a highly eccentric long-period Jovian planet orbiting the hot-Jupiter host HD 83443. By combining radial velocity data from four instruments (AAT/UCLES, Keck/HIRES, HARPS, Minerva-Australis) spanning more than two decades, we find evidence for a planet with m sin $i={1.35}_{-0.06}^{+0.07}$ M J, moving on an or…
Kinematics of the Central Stars Powering Bowshock Nebulae and the Large Multiplicity Fraction of Runaway OB Stars
Kobulnicky, Henry A.; Chick, William T.
OB stars powering stellar bowshock nebulae (SBNe) have been presumed to have large peculiar velocities. We measured peculiar velocities of SBN central stars to assess their kinematics relative to the general O-star population using Gaia EDR3 data for 267 SBN central stars and a sample of 455 Galactic O stars to derive projected velocities v 2…
SOFIA FEEDBACK Survey: PDR Diagnostics of Stellar Feedback in Different Regions of RCW 49
Schneider, N.; Stutzki, J.; Tielens, A. G. G. M. +13 more
We quantified the effects of stellar feedback in RCW 49 by determining the physical conditions in different regions using the [C II] 158 µm and [O I] 63 µm observations from SOFIA, the 12CO (3-2) observations from APEX, and the H2 line observations from Spitzer telescopes. Large maps of RCW 49 were observed with t…
ARMADA. II. Further Detections of Inner Companions to Intermediate-mass Binaries with Microarcsecond Astrometry at CHARA and VLTI
Gies, Douglas R.; Monnier, John D.; Lanthermann, Cyprien +18 more
We started a survey with CHARA/MIRC-X and VLTI/GRAVITY to search for low-mass companions orbiting individual components of intermediate-mass binary systems. With the incredible precision of these instruments, we can detect astrometric "wobbles" from companions down to a few tens of microarcseconds. This allows us to detect any previously unseen tr…
Search for Stellar Flybys in the Sco-Cen OB Association with the Gaia DR2
Kalas, Paul; De Rosa, Robert J.; Ma, Yilun
High-contrast imaging studies of debris disks have revealed a significant diversity in their morphologies, including large-scale asymmetries. Theories involving stellar flybys, an external source of gravitational disturbance, have offered a plausible explanation for the origin of these morphological variations. Our study is an experiment to gain e…
Chemically Peculiar Stars in the Open Cluster Stock 2
Bouy, Hervé; Agüeros, Marcel A.; Gebran, Marwan +2 more
The recently rediscovered open cluster Stock 2, located roughly 375 pc away and about 400 Myr old, has the potential to be an exciting new testbed for our understanding of stellar evolution. We present results from a spectroscopic campaign to characterize stars near the cluster's main-sequence turnoff; our goal is to identify candidate chemically …
Optimal Differential Astrometry for Multiconjugate Adaptive Optics. I. Astrometric Distortion Mapping using On-sky GeMS Observations of NGC 6723
McConnachie, Alan W.; Bono, Giuseppe; Fiorentino, Giuliana +7 more
The Extremely Large Telescope and the Thirty Meter Telescope will use state of the art multiconjugate adaptive optics (MCAO) systems to obtain the full D 4 advantage that their apertures can provide. However, to reach the full astrometric potential of these facilities for on-sky science requires understanding any residual astrometric di…