Search Publications
White dwarf Random Forest classification through Gaia spectral coefficients
Rebassa-Mansergas, Alberto; Torres, Santiago; García-Zamora, Enrique Miguel
Context. The third data release of Gaia has provided approximately 220 million low resolution spectra. Among these, about 100 000 correspond to white dwarfs. The magnitude of this quantity of data precludes the possibility of performing spectral analysis and type determination by human inspection. In order to tackle this issue, we explore the poss…
Models of Rotating Infall for the B335 Protostar
Choi, Minho; Di Francesco, James; Lee, Jeong-Eun +7 more
Models of the protostellar source, B335, are developed using axisymmetric three-dimensional models to resolve conflicts found in one-dimensional models. The models are constrained by a large number of observations, including ALMA, Herschel, and Spitzer data. Observations of the protostellar source B335 with ALMA show redshifted absorption against …
TOI-2525 b and c: A Pair of Massive Warm Giant Planets with Strong Transit Timing Variations Revealed by TESS
Trifonov, Trifon; Henning, Thomas; Kürster, Martin +44 more
The K-type star TOI-2525 has an estimated mass of M = ${0.849}_{-0.033}^{+0.024}$ M ⊙ and radius of R = ${0.785}_{-0.007}^{+0.007}$ R ⊙ observed by the TESS mission in 22 sectors (within sectors 1 and 39). The TESS light curves yield significant transit events of two companions, which show strong transit timing variations (TT…
Evidence for mass-dependent peculiar velocities in compact object binaries: towards better constraints on natal kicks
Maccarone, Thomas J.; Gandhi, Poshak; Zhao, Yue +4 more
We compile a catalogue of low-mass and high-mass X-ray binaries, some recently reported binaries that likely host a neutron star (NS) or a black hole (BH), and binary pulsars (a pulsar and a non-degenerated companion) that have measured systemic radial velocities (γ). Using Gaia and radio proper motions together with γ, we integrate their Galactic…
The R-Process Alliance: Chemodynamically Tagged Groups. II. An Extended Sample of Halo r-process-enhanced Stars
Beers, Timothy C.; Placco, Vinicius M.; Holmbeck, Erika M. +8 more
Orbital characteristics based on Gaia Early Data Release 3 astrometric parameters are analyzed for ~1700 r-process-enhanced (RPE; [Eu/Fe] > +0.3) metal-poor stars ([Fe/H] ≤ -0.8) compiled from the R-Process Alliance, the GALactic Archaeology with HERMES (GALAH) DR3 survey, and additional literature sources. We find dynamical clusters of these s…
Metal-enriched Neutral Gas Reservoir around a Strongly Lensed Low-mass Galaxy at z = 4 Identified by JWST/NIRISS and VLT/MUSE
Chevallard, Jacopo; Fan, Xiaohui; Schaerer, Daniel +19 more
Direct observations of low-mass, low-metallicity galaxies at z ≳ 4 provide an indispensable opportunity for detailed inspection of the ionization radiation, gas flow, and metal enrichment in sources similar to those that reionized the universe. Combining the James Webb Space Telescope (JWST), Very Large Telescope/MUSE, and Atacama Large Millimeter…
X-ray polarimetry of the accreting pulsar GX 301−2
Kaaret, Philip; Wu, Kinwah; Enoto, Teruaki +102 more
The phase- and energy-resolved polarization measurements of accreting X-ray pulsars (XRPs) allow us to test different theoretical models of their emission, and they also provide an avenue to determine the emission region geometry. We present the results of the observations of the XRP GX 301−2 performed with the Imaging X-ray Polarimetry Explorer (…
The MUSE Ultra Deep Field (MUDF). III. Hubble Space Telescope WFC3 Grism Spectroscopy and Imaging
Papovich, Casey; Henry, Alaina; Rafelski, Marc +18 more
We present extremely deep Hubble Space Telescope (HST) Wide Field Camera 3 (WFC3) observations of the MUSE Ultra Deep Field. This unique region of the sky contains two quasars at z ≈ 3.22 that are separated by only ~500 kpc, providing a stereoscopic view of gas and galaxies in emission and absorption across ~10 billion years of cosmic time. We hav…
Updated radial velocities and new constraints on the nature of the unseen source in NGC1850 BH1
Usher, C.; Bastian, N.; Saracino, S. +7 more
A black hole candidate orbiting a luminous star in the Large Magellanic Cloud young cluster NGC 1850 (~100 Myr) has recently been reported based on radial velocity and light-curve modelling. Subsequently, an alternative explanation has been suggested for the system: a bloated post-mass transfer secondary star (Minitial ~ 4-5 M⊙
An Updated Dust-to-Star Geometry: Dust Attenuation Does Not Depend on Inclination in 1.3 ≤z ≤2.6 Star-forming Galaxies from MOSDEF
Barro, Guillermo; Siana, Brian; Shapley, Alice E. +10 more
We investigate dust attenuation and its dependence on viewing angle for 308 star-forming galaxies at 1.3 ≤ z ≤ 2.6 from the MOSFIRE Deep Evolution Field survey. We divide galaxies with a detected Hα emission line and coverage of Hβ into eight groups by stellar mass, star formation rate (SFR), and inclination (i.e., axis ratio), and we then stack t…