Search Publications
Spectroscopy of Candidate Members of the Sco-Cen Complex
Luhman, K. L.; Esplin, T. L.
We present spectroscopy of 285 previously identified candidate members of populations in the Sco-Cen complex, primarily Ophiuchus, Upper Sco, and Lupus. The spectra are used to measure spectral types and diagnostics of youth. We find that 269 candidates exhibit signatures of youth in our spectra or previous data, which is consistent with their mem…
ACCESS: Tentative Detection of H2O in the Ground-based Optical Transmission Spectrum of the Low-density Hot Saturn HATS-5b
Kirk, James; López-Morales, Mercedes; Jordán, Andrés +13 more
We present a precise ground-based optical transmission spectrum of the hot Saturn HATS-5b (T eq = 1025 K), obtained as part of the ACCESS survey with the IMACS multi-object spectrograph mounted on the Magellan Baade Telescope. Our spectra cover the 0.5-0.9 µm region and are the product of five individual transits observed between …
Fragment Dynamics in Active Asteroid 331P/Gibbs
Jewitt, David; Hui, Man-To
We present a dynamical analysis of the fragmented active asteroid 331P/Gibbs. Using archival images taken by the Hubble Space Telescope from 2015 to 2018, we measured the astrometry of the primary and the three brightest (presumably the largest) components. Conventional orbit determination revealed a high degree of orbital similarity between the c…
The Interferometric Binary ϵ Cnc in Praesepe: Precise Masses and Age
Klement, Robert; Monnier, John D.; Schaefer, Gail H. +16 more
We observe the brightest member of the Praesepe cluster, ϵ Cnc, to precisely measure the characteristics of the stars in this binary system, en route to a new measurement of the cluster's age. We present spectroscopic radial velocity measurements and interferometric observations of the sky-projected orbit to derive the masses, which we find to be …
Constraining the Size of the Circumgalactic Medium Using the Transverse Autocorrelation Function of C IV Absorbers in Paired Quasar Spectra
Martin, Crystal L.; Rafelski, Marc; Jorgenson, Regina A. +6 more
The circumgalactic medium (CGM) plays a vital role in the formation and evolution of galaxies, acting as a lifeline between galaxies and the surrounding intergalactic medium. In this study, we leverage a unique sample of quasar pairs to investigate the properties of the CGM with absorption line tomography. We present a new sample of medium-resolut…
A New Third Planet and the Dynamical Architecture of the HD 33142 Planetary System
Trifonov, Trifon; Stock, Stephan; Henning, Thomas +24 more
Based on recently-taken and archival HARPS, FEROS, and HIRES radial velocities (RVs), we present evidence for a new planet orbiting the first ascent red giant star HD 33142 (with an improved mass estimate of M1.52 ± 0.03 M ⊙), already known to host two planets. We confirm the Jovian-mass planets HD 33142b and c, with periods of P b…
On the Same Wavelength as the Space Telescope Imaging Spectrograph
Ayres, Thomas R.
The Hubble Space Telescope Imaging Spectrograph (STIS) is a powerful tool for high spectral resolution ultraviolet (UV; 1150-3200 Å) studies of bright cosmic sources. However, achieving the superb wavelength precision inherent in its UV echelle channels is hampered by subtle camera distortions that are not fully compensated for by the CALSTIS pipe…
An Unusual Reservoir of Water Emission in the VV CrA A Protoplanetary Disk
Pascucci, Ilaria; Banzatti, Andrea; Carmona, Andrés +7 more
We present an analysis of an unusual pattern of water vapor emission from the ~2 Myr old low-mass binary system VV CrA, as observed in IR spectra obtained with VLT-CRIRES, VLT-VISIR, and Spitzer-IRS. Each component of the binary shows emission from water vapor in both the L (~3 µm) and N (~12 µm) bands. The N-band and Spitzer spectra a…
Environmental Effects in Herschel Observations of the Ionized Carbon Content of Star-forming Dwarf Galaxies in the Virgo Cluster
Fadda, Dario; Davies, Jonathan; Minchin, Robert +2 more
We use archival Herschel data to examine the singly ionized carbon ([C II]) content of 14 star-forming dwarf galaxies in the Virgo cluster. We use spectral energy distribution fits to far-infrared, mid-infrared, near-infrared, optical, and ultraviolet data to derive the total infrared continuum (TIR) for these galaxies. We compare the [C II]/TIR r…
NICMOS Kernel-phase Interferometry. I. Catalogue of Brown Dwarfs Observed in F110W and F170M
Kraus, Adam L.; Factor, Samuel M.
Filling out the dearth of detections between direct imaging and radial velocity surveys will test theories of planet formation and (sub)stellar binarity across the full range of semimajor axes, connecting formation of close- to wide-separation gas giants and substellar companions. Direct detection of close-in companions is notoriously difficult: c…