Search Publications
DR 21 South Filament: A Parsec-sized Dense Gas Accretion Flow onto the DR 21 Massive Young Cluster
Qiu, Keping; Li, Guangxing; Liu, Junhao +8 more
DR 21 south filament (DR21SF) is a unique component of the giant network of filamentary molecular clouds in the north region of the Cygnus X complex. Unlike the highly fragmented and star-forming active environment wherein it resides, DR21SF exhibits a coherent profile in the column density map with very few star formation signposts, even though t…
Gaia EDR3 Parallax Distances to the Great Carina Nebula and Its Star Clusters (Trumpler 14, 15, 16)
Shull, J. Michael; Danforth, Charles W.; Darling, Jeremy
Using offset-corrected Gaia EDR3 parallax measurements and spectrophotometric methods, we have determined distances for 69 massive stars in the Carina OB1 association and associated clusters: Trumpler 16 (21 stars), Trumpler 14 (20 stars), Trumpler 15 (three stars), Bochum 11 (five stars), and South Pillars region (20 stars). Past distance estimat…
Signature of a Heliotail Organized by the Solar Magnetic Field and the Role of Nonideal Processes in Modeled IBEX ENA Maps: A Comparison of the BU and Moscow MHD Models
Galli, A.; Richardson, J. D.; Zank, G. P. +9 more
Energetic neutral atom (ENA) models typically require post-processing routines to convert the distributions of plasma and H atoms into ENA maps. Here we investigate how two kinetic-MHD models of the heliosphere (the BU and Moscow models) manifest in modeled ENA maps using the same prescription and how they compare with Interstellar Boundary Explor…
A Low-mass Cold and Quiescent Core Population in a Massive Star Protocluster
Sanhueza, Patricio; Smith, Howard A.; Qiu, Keping +23 more
Pre-stellar cores represent the initial conditions of star formation. Although these initial conditions in nearby low-mass star-forming regions have been investigated in detail, such initial conditions remain vastly unexplored for massive star-forming regions. We report the detection of a cluster of low-mass starless and pre-stellar core candidate…
Impact of the Disk Thickness on X-Ray Reflection Spectroscopy Measurements
Tripathi, Ashutosh; Abdikamalov, Askar B.; Ayzenberg, Dimitry +2 more
In a previous paper, we presented an extension of our reflection model relxill_nk to include the finite thickness of the accretion disk following the prescription in Taylor & Reynolds. In this paper, we apply our model to fit the 2013 simultaneous observations by the Nuclear Spectroscopic Telescope Array (NuSTAR) and XMM-Newton of the supermas…
Evidence of Rocky Planet Engulfment in the Wide Binary System HIP 71726/HIP 71737
Meléndez, Jorge; Yana Galarza, Jhon; Lorenzo-Oliveira, Diego +1 more
Binary stars are supposed to be chemically homogeneous, as they are born from the same molecular cloud. However, high-precision chemical abundances show that some binary systems display chemical differences between the components, which could be due to planet engulfment. In this work, we determine precise fundamental parameters and chemical abunda…
Fermi-GBM Observations of GRB 210812A: Signatures of a Million Solar Mass Gravitational Lens
Veres, P.; Fraija, N.; Bhat, N. +1 more
Observing gravitationally lensed objects in the time domain is difficult, and well-observed time-varying sources are rare. Lensed gamma-ray bursts (GRBs) offer improved timing precision for this class of objects, complementing observations of quasars and supernovae. The rate of lensed GRBs is highly uncertain, approximately one in 1000. The Gamma-…
Testing the Limits of Precise Subgiant Characterization with APOGEE and Gaia: Opening a Window to Unprecedented Astrophysical Studies
Stassun, Keivan G.; van Saders, Jennifer L.; Beaton, Rachael L. +6 more
Given their location on the Hertzsprung-Russell (H-R) diagram, thoroughly characterized subgiant stars can place stringent constraints on a wide range of astrophysical problems. Accordingly, they are prime asteroseismic targets for the Transiting Exoplanet Survey Satellite (TESS) mission. In this work, we infer stellar properties for a sample of 3…
On the Use of Field RR Lyrae as Galactic Probes. V. Optical and Radial Velocity Curve Templates
Lemasle, B.; Latour, M.; Zoccali, M. +29 more
We collected the largest spectroscopic catalog of RR Lyrae (RRLs) including ≈20,000 high-, medium-, and low-resolution spectra for ≈10,000 RRLs. We provide the analytical forms of radial velocity curve (RVC) templates. These were built using 36 RRLs (31 fundamental-split into three period bins-and five first-overtone pulsators) with well-sampled R…
The Lithium Abundances from the Large Sky Area Multi-object Fiber Spectroscopic Telescope Medium-resolution Survey. I. The Method
Zhang, Yong; Gao, Qi; Yan, Hong-Liang +9 more
One of the purposes of taking spectra for millions of stars through the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) medium-resolution survey (MRS) is to obtain the elemental abundances, so that one can trace the origin and evolution for the element of interests. Lithium is one of such elements of great importance, which exhi…