Search Publications
Light-curve Evolution of the Nearest Tidal Disruption Event: A Late-time, Radio-only Flare
Yuan, Qiang; Perlman, Eric S.; Meyer, Eileen T. +7 more
Tidal disruption events (TDEs) occur when a star passes close enough to a galaxy's supermassive black hole to be disrupted by tidal forces. We discuss new observations of IGRJ12580+0134, a TDE observed in NGC 4845 (d = 17 Mpc) in 2010 November, with the Karl G. Jansky Very Large Array (VLA 9 9 The National Radio Astronomy Obs…
The Unmixed Debris of Gaia-Sausage/Enceladus in the Form of a Pair of Halo Stellar Overdensities
Chiappini, Cristina; Limberg, Guilherme; Rossi, Silvia +5 more
In the first billion years after its formation, the Galaxy underwent several mergers with dwarf satellites of various masses. The debris of Gaia-Sausage/Enceladus (GSE), the galaxy responsible for the last significant merger of the Milky Way, dominates the inner halo and has been suggested to be the progenitor of both the Hercules-Aquila Cloud (HA…
Discovery of Three Candidate Magnetar-powered Fast X-Ray Transients from Chandra Archival Data
Berger, Edo; Lin, Dacheng; Irwin, Jimmy A. +1 more
It was proposed that a remnant stable magnetar could be formed in a binary neutron-star merger, leading to a fast X-ray transient (FXT) that can last for thousands of seconds. Recently, Xue et al. suggested that CDF-S XT2 was exactly such a kind of source. If confirmed, such emission can be used to search for electromagnetic counterparts to gravit…
The Kiloparsec-scale Neutral Atomic Carbon Outflow in the Nearby Type 2 Seyfert Galaxy NGC 1068: Evidence for Negative AGN Feedback
Tamura, Yoichi; Kohno, Kotaro; Schinnerer, Eva +13 more
Active galactic nucleus (AGN) feedback is postulated as a key mechanism for regulating star formation within galaxies. Studying the physical properties of the outflowing gas from AGNs is thus crucial for understanding the coevolution of galaxies and supermassive black holes. Here we report 55 pc resolution ALMA neutral atomic carbon [C I] 3
Thermal Instability-Induced Fundamental Magnetic Field Strands in the Solar Corona
Antolin, Patrick; Martínez-Sykora, Juan; Şahin, Seray
Thermal instability is a fundamental process of astrophysical plasmas. It is expected to occur whenever the cooling is dominated by radiation and cannot be compensated for by heating. In this work, we conduct 2.5D radiation MHD simulations with the Bifrost code of an enhanced activity network in the solar atmosphere. Coronal loops are produced sel…
Milky Way Thin and Thick Disk Kinematics with Gaia EDR3 and RAVE DR5
Girard, Terrence M.; Vieira, Katherine; Carraro, Giovanni +3 more
We present a detailed analysis of kinematics of the Milky Way disk in the solar neighborhood using the Gaia DR3 catalog. To determine the local kinematics of the stellar disks of the Milky Way we use a complete sample of 278,228 red giant branch (RGB) stars distributed in a cylinder, centered at the Sun with a 1 kpc radius and half-height of 0.5 k…
Strong H2O and CO Emission Features in the Spectrum of KELT-20b Driven by Stellar UV Irradiation
Deming, Drake; Sing, David K.; Fu, Guangwei +7 more
Know thy star, know thy planetary atmosphere. Every exoplanet with atmospheric measurements orbits around a star, and the stellar environment directly affects the planetary atmosphere. Here we present the emission spectrum of ultra-hot Jupiter KELT-20b which provides an observational link between host-star properties and planet atmospheric thermal…
Sculpting the Sub-Saturn Occurrence Rate via Atmospheric Mass Loss
Lee, Eve J.; Hallatt, Tim
The sub-Saturn (~4-8 R ⊕) occurrence rate rises with orbital period out to at least ~300 days. In this work we adopt and test the hypothesis that the decrease in their occurrence toward the star is a result of atmospheric mass loss, which can transform sub-Saturns into sub-Neptunes (≲4 R ⊕) more efficiently at shorter periods…
Modeling the Hα and He 10830 Transmission Spectrum of WASP-52b
Yan, Dongdong; Seon, Kwang-il; Guo, Jianheng +2 more
Escaping atmosphere has been detected by the excess absorption of Lyα, Hα and He triplet (λ10830) lines. Simultaneously modeling the absorption of the Hα and He λ10830 lines can provide useful constraints about the exoplanetary atmosphere. In this paper, we use a hydrodynamic model combined with a non-local thermodynamic model and a new Monte Carl…
New Constraints on the Future Evaporation of the Young Exoplanets in the V1298 Tau System
Sozzetti, A.; Micela, G.; Damasso, M. +7 more
Transiting planets at young ages are key targets for improving our understanding of the evolution of exo-atmospheres. We present results of a new X-ray observation of V 1298 Tau with XMM-Newton, aimed to determine more accurately the high-energy irradiation of the four planets orbiting this pre-main-sequence star, and the possible variability due …