Search Publications
A Surprising Excess of Radio Emission in Extremely Stable Quasars: A Unique Clue to Jet Launching?
Cai, Zhen-Yi; Wang, Jun-Xian; Yuan, Feng +6 more
Quasars are generally divided into jetted radio-loud and nonjetted radio-quiet ones, but why only 10% of quasars are radio-loud has been puzzling for decades. Other than jet-induced phenomena, black hole mass, or Eddington ratio, a prominent difference between jetted and nonjetted quasars has scarcely been detected. Here we show a unique distincti…
Effects of ultrafast outflows on X-ray time lags in active galactic nuclei
Bianchi, Stefano; Kara, Erin; Tombesi, Francesco +3 more
Context. The time lag between soft (e.g., 0.3–1 keV) and hard (e.g., 1–4 keV) X-ray photons has been observed in many active galactic nuclei (AGNs) and can reveal the accretion process and geometry around supermassive black holes. High-frequency Fe K and soft lags are considered to originate from the light-travel distances between the corona and t…
Pulsational and eclipsing nature of TIC 140736015
Gürol, B.; Zhou, A. -Y.
We present the discovery of
Validation of the Bond et al. (2010) SDSS-derived kinematic models for the Milky Way's disk and halo stars with Gaia Data Release 3 proper motion and radial velocity data
Ivezić, Željko; Domínguez, Bruno; Chaini, Siddharth +2 more
We validate the Bond et al. (2010, ApJ, 716, 1) kinematic models for the Milky Way's disk and halo stars with Gaia Data Release 3 data. Bond et al. constructed models for stellar velocity distributions using stellar radial velocities measured by the Sloan Digital Sky Survey (SDSS) and stellar proper motions derived from SDSS and the Palomar Observ…
Analysis of KIC 7023917: Spotted Low-mass Ratio Eclipsing Binary with δ Scuti Pulsations
Skarka, Marek; Karjalainen, Raine; Gajdoš, Pavol +3 more
Times of minima of eclipsing binary KIC 7023917 show quasiperiodic anti-symmetric deviations from the calculated one with an amplitude of up to 10 minutes and a period of 200–300 days. These changes correlate with the observed variations of the light-curve maxima (amplitude and phase separation). We used photometric data obtained by Kepler and TES…
An Extremely Low-density Exoplanet Spins Slow
Zhu, Wei; Cañas, Caleb I.; Bello-Arufe, Aaron +3 more
We present constraints on the shape of Kepler-51d, which is a superpuff with a mass ∼6 M ⊕ and a radius ∼9 R ⊕, based on detailed modeling of the transit light curve from James Webb Space Telescope (JWST) NIRSpec. The projected shape of this extremely low-density planet is consistent with being spherical, and a projected obla…
Investigating the nuclear properties of highly accreting active galactic nuclei with XMM-Newton
Guainazzi, M.; Vignali, C.; Piconcelli, E. +7 more
Highly accreting active galactic nuclei (AGNs) have unique features that make them ideal laboratories for studying black hole accretion physics under extreme conditions. However, our understanding of the nuclear properties of these sources is hampered by the lack of a complete systematic investigation of this AGN class in terms of their main spect…
Probing the emission mechanism and nature of the pulsating compact object in the X-ray binary SAX J1324.4−6200
Santangelo, A.; Serim, M. M.; Ducci, L. +6 more
Recently, there has been renewed interest in the Be X-ray binary (Be/XRB) SAX J1324.4−6200 because of its spatial coincidence with a variable γ-ray source detected by Fermi/LAT. To explore more thoroughly its properties, new X-ray observations were carried out in 2023 by NuSTAR, XMM-Newton, and Swift satellites, jointly covering the energy range f…
DECam Multimessenger Astrophysics Pipeline. I. From Raw Data to Single-exposure Candidates
Matheson, Thomas; Meisner, Aaron; Fu, Shenming +3 more
We introduce a pipeline that performs rapid image subtraction and source selection to detect transients, with a focus on identifying gravitational-wave optical counterparts using the Dark Energy Camera (DECam). In this work, we present the pipeline steps from processing raw data to identification of astrophysical transients on individual exposures…
The chemical evolution of the Milky Way thin disk using solar twins
Spina, L.; Carraro, G.; Casali, G. +2 more
Aims. In this study we address whether the age-metallicity relation (AMR) deviates from the expected trend of metallicity increasing smoothly with age. We also show the presence (or absence) of two populations, as recently claimed using a relatively small dataset. Moreover, we studied the Milky Way thin disk's chemical evolution using solar twins,…