Search Publications
Missions
Journals
Publication Years
Revisiting the Properties of X-Ray Active Galactic Nuclei in the SSA22 Protocluster: Normal Supermassive Black Hole and Host-galaxy Growth for AGNs in a z = 3.09 Overdensity
Kubo, Mariko; Umehata, Hideki; Alexander, David M. +6 more
We analyze the physical properties of eight X-ray-selected active galactic nuclei (AGNs) and one candidate protoquasar system (ADF22A1) in the z = 3.09 SSA22 protocluster by fitting their X-ray-to-IR spectral energy distributions (SEDs) using our SED-fitting code, LIGHTNING (https://www.github.com/rafaeleufrasio/lightning). We recover star formati…
Swing amplification and the Gaia phase spirals
Widrow, Lawrence M.
We explore the interplay between in-plane and vertical dynamics in stellar discs within the framework of the shearing box approximation. Julian and Toomre used the shearing sheet to show that leading density waves are amplified as they swing into trailing ones. We extend their formalism into the dimension perpendicular to the disc to obtain explic…
Surveying nearby brown dwarfs with HGCA: direct imaging discovery of a faint, high-mass brown dwarf orbiting HD 176535 A
Jensen-Clem, Rebecca; Currie, Thayne; Lewis, Briley L. +17 more
Brown dwarfs with well-measured masses, ages, and luminosities provide direct benchmark tests of substellar formation and evolutionary models. We report the first results from a direct imaging survey aiming to find and characterize substellar companions to nearby accelerating stars with the assistance of the Hipparcos-Gaia Catalog of Accelerations…
Gravitational wave physics and astronomy in the nascent era
Fukazawa, Yasushi; Sugita, Satoshi; Sakamoto, Takanori +50 more
The detections of gravitational waves (GW) by the LIGO/Virgo collaborations provide various possibilities for both physics and astronomy. We are quite sure that GW observations will develop a lot, both in precision and in number, thanks to the continuous work on the improvement of detectors, including the expected new detector, KAGRA, and the plan…
Simultaneous Global Ionospheric Disturbances Associated With Penetration Electric Fields During Intense and Minor Solar and Geomagnetic Disturbances
Nishimura, Yukitoshi; Zhang, Shun-Rong; Vierinen, Juha +8 more
A new observational phenomenon, named Simultaneous Global Ionospheric Density Disturbance (SGD), is identified in GNSS total electron content (TEC) data during periods of three typical geospace disturbances: a Coronal Mass Ejection-driven severe disturbance event, a high-speed stream event, and a minor disturbance day with a maximum Kp of 4. SGDs …
HST Imaging of Star-forming Clumps in Six GASP Ram-pressure-stripped Galaxies
Scarlata, Claudia; Calzetti, Daniela; Vulcani, Benedetta +6 more
Exploiting broad- and narrowband images of the Hubble Space Telescope from the near-UV to I-band rest frame, we study the star-forming clumps of six galaxies of the GASP sample undergoing strong ram pressure stripping. Clumps are detected in Hα and near-UV, tracing star formation on different timescales. We consider clumps located in galaxy disks …
AGN STORM 2. III. A NICER View of the Variable X-Ray Obscurer in Mrk 817
Kaspi, Shai; Filippenko, Alexei V.; Hall, Patrick B. +46 more
The AGN STORM 2 Collaboration targeted the Seyfert 1 galaxy Mrk 817 for a year-long multiwavelength, coordinated reverberation mapping campaign including Hubble Space Telescope, Swift, XMM-Newton, NICER, and ground-based observatories. Early observations with NICER and XMM revealed an X-ray state 10 times fainter than historical observations, cons…
The miniJPAS survey. Cluster and galaxy group detections with AMICO
Finoguenov, A.; Diego, J. M.; Zitrin, A. +32 more
Context. Samples of galaxy clusters allow us to better understand the physics at play in galaxy formation and to constrain cosmological models once the mass, position (for clustering studies), and redshift are known. In this context, large optical datasets play a crucial role.
Aims: We investigate the capabilities of the Javalambre-Physics of…
Did the Milky Way just light up? The recent star formation history of the Galactic disc
Rix, Hans-Walter; Zari, Eleonora; Frankel, Neige
We map the stellar age distribution (≲1 Gyr) across a 6 kpc × 6 kpc area of the Galactic disc in order to constrain our Galaxy's recent star formation history. Our modelling draws on a sample that encompasses all presumed disc O-, B-, and A-type stars (∼500 000 sources) with G < 16. To be less sensitive to reddening, we did not forward-model th…
Swift and XMM-Newton observations of an RS CVn-type eclipsing binary SZ Psc: superflare and coronal properties
Karmakar, Subhajeet; Naik, Sachindra; Pandey, Jeewan C. +1 more
We present an in-depth study of a large and long duration (>1.3 d) X-ray flare observed on an RS CVn-type eclipsing binary system SZ Psc using observations from Swift observatory. In the 0.35-10 keV energy band, the peak luminosity is estimated to be 4.2 × 1033 $\rm {erg}~\rm {s}^{-1}$. The quiescent corona of SZ Psc was observed ~5.…