Search Publications
A Second Planet Transiting LTT 1445A and a Determination of the Masses of Both Worlds
Butler, R. Paul; Kristiansen, Martti H.; Omohundro, Mark +79 more
LTT 1445 is a hierarchical triple M-dwarf star system located at a distance of 6.86 pc. The primary star LTT 1445A (0.257 M ⊙) is known to host the transiting planet LTT 1445Ab with an orbital period of 5.36 days, making it the second-closest known transiting exoplanet system, and the closest one for which the host is an M dwarf. Using …
X-Ray Coronal Properties of Swift/BAT-selected Seyfert 1 Active Galactic Nuclei
Ricci, Claudio; Stern, Daniel; Urry, C. Megan +9 more
The corona is an integral component of active galactic nuclei (AGNs) which produces the bulk of the X-ray emission above 1-2 keV. However, many of its physical properties and the mechanisms powering this emission remain a mystery. In particular, the temperature of the coronal plasma has been difficult to constrain for large samples of AGNs, as con…
Godzilla, a monster lurks in the Sunburst galaxy
Diego, J. M.; Kelly, P.; Broadhurst, T. +4 more
We model the strong lensing effect in the galaxy cluster PSZ1 G311.65-18.48 (z = 0.443) with an improved version of the hybrid method WSLAP+. We extend the number of constraints by including the position of critical points, which are combined with the classic positional constraints of the lensed galaxies. We pay special attention to a transient ca…
STEPARSYN: A Bayesian code to infer stellar atmospheric parameters using spectral synthesis
Montes, D.; González Hernández, J. I.; Tabernero, H. M. +1 more
Context. STEPARSYN is an automatic code written in Python 3.X designed to infer the stellar atmospheric parameters Teff, log g, and [Fe/H] of FGKM-type stars following the spectral synthesis method.
Aims: We present a description of the STEPARSYN code and test its performance against a sample of late-type stars that were observed w…
One year of AU Mic with HARPS - I. Measuring the masses of the two transiting planets
Owen, James E.; Aigrain, Suzanne; Gandolfi, Davide +11 more
The system of two transiting Neptune-sized planets around the bright, young M-dwarf AU Mic provides a unique opportunity to test models of planet formation, early evolution, and star-planet interaction. However, the intense magnetic activity of the host star makes measuring the masses of the planets via the radial velocity (RV) method very challen…
The Recent LMC-SMC Collision: Timing and Impact Parameter Constraints from Comparison of Gaia LMC Disk Kinematics and N-body Simulations
Choi, Yumi; van der Marel, Roeland P.; Nidever, David L. +4 more
We present analysis of the proper-motion (PM) field of the red clump stars in the Large Magellanic Cloud (LMC) disk using the Gaia Early Data Release 3 catalog. Using a kinematic model based on old stars with 3D velocity measurements, we construct the residual PM field by subtracting the center-of-mass motion and internal rotation motion component…
Luminous Supernovae: Unveiling a Population between Superluminous and Normal Core-collapse Supernovae
Berger, Edo; Nicholl, Matt; Hosseinzadeh, Griffin +2 more
Stripped-envelope core-collapse supernovae can be divided into two broad classes: the common Type Ib/c supernovae (SNe Ib/c), powered by the radioactive decay of 56Ni, and the rare superluminous supernovae (SLSNe), most likely powered by the spin-down of a magnetar central engine. Up to now, the intermediate regime between these two pop…
Luminous Millimeter, Radio, and X-Ray Emission from ZTF 20acigmel (AT 2020xnd)
Kaplan, David L.; Petitpas, Glen; Perley, Daniel A. +7 more
Observations of the extragalactic (z = 0.0141) transient AT 2018cow established a new class of energetic explosions shocking a dense medium, producing luminous emission at millimeter and submillimeter wavelengths. Here we present detailed millimeter- through centimeter-wave observations of a similar transient, ZTF 20acigmel (AT 2020xnd), at z = 0.…
ALMA Reveals Extended Cool Gas and Hot Ionized Outflows in a Typical Star-forming Galaxy at Z = 7.13
Richard, Johan; Fujimoto, Seiji; Inoue, Akio K. +9 more
We present spatially resolved morphological properties of [C II] 158 µm, [O III] 88 µm, dust, and rest-frame ultraviolet (UV) continuum emission for A1689-zD1, a strongly lensed, sub-L* galaxy at z = 7.13, by utilizing deep Atacama Large Millimeter/submillimeter Array (ALMA) and Hubble Space Telescope (HST) observations. While the [O I…
A Blind All-sky Search for Star Clusters in Gaia EDR3: 886 Clusters within 1.2 kpc of the Sun
Luo, Yangping; Wang, Kun; Liu, Xiaochen +3 more
Although previous searches for star clusters have been very successful, many clusters are likely still omitted, especially at high-Galactic-latitude regions. In this work, based on the astrometry of Gaia EDR3, we searched nearby (ϖ > 0.8 mas) all-sky regions, obtaining 886 star clusters, of which 270 candidates have not been cataloged before. A…