Search Publications
KIC 4150611: A quadruply eclipsing heptuple star system with a g-mode period-spacing pattern: Asteroseismic modelling of the g-mode period-spacing pattern
Li, Gang; Aerts, Conny; Van Reeth, Timothy +7 more
Context. KIC 4150611 is a high-order (seventh-order) multiple composed of a triple system with: a F1V primary (Aa), which is eclipsed on a 94.2 d period by a tight binary composed of two K/M dwarfs (Ab1 and Ab2) that also eclipse each other; an eccentric, eclipsing binary composed of two G stars (Ba and Bb); and another faint eclipsing binary comp…
Chandra Follow-up Observations of Swift-BAT-selected AGNs III
Marchesi, Stefano; Zhao, Xiurui; Ajello, Marco +5 more
The cosmic X-ray background (CXB) is dominated by the obscured and unobscured coronal light of active galactic nuclei (AGN). At energies below 10 keV, the CXB can be well explained by models taking into account the known AGN and the observed distribution of their obscuring, line-of-sight column densities, NH,l.o.s. However, at energies …
Geometrical Distances of Extragalactic Binaries through Spectroastrometry
Zhang, Zhi-Xiang; Wang, Jian-Min; Cai, Rong-Gen +4 more
The growing "Hubble tension" has prompted the need for precise measurements of cosmological distances. This paper demonstrates a purely geometric approach for determining the distances to extragalactic binaries through a joint analysis of spectroastrometry (SA), radial velocity (RV), and light-curve (LC) observations. A parameterized model for the…
XMM-Newton Observations of the Peculiar Be X-Ray Binary A0538-66
Mereghetti, Sandro; Rigoselli, Michela; Ducci, Lorenzo +1 more
A0538-66 is a neutron star/Be x-ray binary located in the Large Magellanic Cloud and, since its discovery in the 70s, it showed a peculiar behavior that makes it a unique object in the high-mass x-ray binaries scene: the extremely eccentric orbit ($$ e=0.72 $$), the short spin period of the neutron star ($$ P=69 $$ ms), the episodes of super-Eddin…
A Systematic Search for Redback and Black Widow Candidates Based on the 4FGL-DR3 Unassociated Sources and the Zwicky Transient Facility Data
Lin, Jiamao; Ren, Liangliang; Lu, Chunyan +3 more
Spider pulsars represent a unique subclass of radio millisecond pulsars in binaries, and are further categorized into black widows and redbacks according to the mass of the low-mass companion. These pulsars, observable across multiple wavelengths, exhibit periodic variability in optical. The discovery and study of additional spider-type pulsars ar…
Centaur 29P/Schwassmann-Wachmann 1 and its near-nucleus environment from a stellar occultation
Sicardy, B.; Ortiz, J. L.; Desmars, J. +9 more
Comets offer valuable insights into the early Solar System's conditions and processes. Stellar occultations enable detailed study of cometary nuclei typically hidden by their coma. Observing the star's light passing through the coma helps infer dust's optical depth near the nucleus and determine dust opacity detection limits. 29P/Schwassmann-Wachm…
Detection of ubiquitous circumbinary matter in hot subdwarfs formed from common-envelope ejections
Han, Zhanwen; Chen, Xuefei; Wolf, Christian +7 more
The formation of compact binary systems is largely driven by their evolution through a common envelope (CE) phase, crucial for understanding phenomena such as type Ia supernovae and black hole mergers. Despite their importance, direct observational evidence for CE material has been elusive due to the transient nature of these envelopes. Numerical …
INTEGRAL Observations of Magnetars
Mereghetti, Sandro; Ducci, Lorenzo; Pacholski, Dominik Patryk +1 more
The INTEGRAL satellite has collected a large amount of data on magnetars in our Galaxy, spanning more than 20 years starting from 2003. The large data set obtained with the IBIS/ISGRI instrument at energies above 20 keV allows us to study both the properties and long-term evolution of their persistent hard X-ray emission and the population charact…
MINCE: III. Detailed chemical analysis of the UVES sample
Hansen, C. J.; Bonifacio, P.; Caffau, E. +14 more
Context. The Measuring at Intermediate Metallicity Neutron-Capture Elements (MINCE) project aims to provide high-quality neutron-capture abundances measurements for several hundred stars at an intermediate metallicity of ‑2.5 < [Fe/H] < ‑1.5. This project will shed light on the origin of the neutron-capture elements and the chemical enrichme…
A Multi-faceted View of the X-Ray Spectral Variability in Seyfert Galaxy Ark 120
Kang, Jia-Lai; Wang, Jun-Xian; Ren, Lu-Xin
Utilizing a range of techniques including multi-band light curves, softness ratio analysis, structure functions, rms spectra, cross-correlation functions, and ratios of spectra from different intervals, we present a comprehensive study of the complex X-ray spectral variability in Seyfert 1 galaxy Ark 120, through re-analyzing its six XMM-Newton ob…