Search Publications
The X-ray disc/wind degeneracy in AGN
Dauser, T.; Matzeu, G. A.; Parker, M. L. +4 more
Relativistic Fe K emission lines from accretion discs and from disc winds encode key information about black holes, and their accretion and feedback mechanisms. We show that these two processes can in principle produce indistinguishable line profiles, such that they cannot be disentangled spectrally. We argue that it is likely that in many cases b…
Cosmological model-independent measurement of cosmic curvature using distance sum rule with the help of gravitational waves
Zhang, Jing-Fei; Zhang, Xin; Wang, Bo +3 more
Although the cosmic curvature has been tightly constrained in the standard cosmological model using observations of cosmic microwave background anisotropies, it is still of great importance to independently measure this key parameter using only late-Universe observations in a cosmological model-independent way. The distance sum rule in strong grav…
First Hard X-Ray Imaging Results by Solar Orbiter STIX
Volpara, Anna; Massa, Paolo; Krucker, Säm +15 more
The Spectrometer/Telescope for Imaging X-rays (STIX) is one of six remote sensing instruments on-board Solar Orbiter. The telescope applies an indirect imaging technique that uses the measurement of 30 visibilities, i.e., angular Fourier components of the solar flare X-ray source. Hence, the imaging problem for STIX consists of the Fourier inversi…
The MMX rover: performing in situ surface investigations on Phobos
Michel, Patrick; Murdoch, Naomi; Zhang, Yun +22 more
The Japanese MMX sample return mission to Phobos by JAXA will carry a rover developed by CNES and DLR that will be deployed on Phobos to perform in situ analysis of the Martian moon's surface properties. Past images of the surface of Phobos show that it is covered by a layer of regolith. However, the mechanical and compositional properties of this…
The disturbed outer Milky Way disc
Chemin, Laurent; Bland-Hawthorn, Joss; Khanna, Shourya +9 more
The outer parts of the Milky Way's disc are significantly out of equilibrium. Using only distances and proper motions of stars from Gaia's Early Data Release 3, in the range |b| < 10°, 130° < ℓ < 230°, we show that for stars in the disc between around 10 and $14\, \mathrm{kpc}$ from the Galactic centre, vertical velocity is strongly depen…
Can high-redshift Hubble diagrams rule out the standard model of cosmology in the context of cosmography?
Pourojaghi, S.; Zabihi, N. F.; Malekjani, M.
Using mock data for the Hubble diagrams of type Ia supernovae (SNIa) and quasars (QSOs) generated based on the standard model of cosmology, and using the least-squares method based on the Markov-Chain-Monte-Carlo (MCMC) algorithm, we first put constraints on the cosmographic parameters in the context of the various model-independent cosmographic m…
A panchromatic view of infrared quasars: excess star formation and radio emission in the most heavily obscured systems
Calistro Rivera, Gabriela; Lapi, Andrea; Villforth, Carolin +13 more
To understand the active galactic nuclei (AGNs) phenomenon and their impact on the evolution of galaxies, a complete AGN census is required; however, finding heavily obscured AGNs is observationally challenging. Here we use the deep and extensive multiwavelength data in the COSMOS field to select a complete sample of 578 infrared (IR) quasars ($L_…
The structure of jets launched from post-AGB binary systems
De Marco, O.; Verhamme, O.; Van Winckel, H. +4 more
Context. In this paper, we focus on post-asymptotic giant branch (post-AGB) binaries and study the interaction between the different components of these complex systems. These components comprise the post-AGB primary, a main sequence secondary, a circumbinary disk, as well as a fast bipolar outflow (jet) launched by the companion. We obtained well…
Elemental Abundances of nearby M Dwarfs Based on High-resolution Near-infrared Spectra Obtained by the Subaru/IRD Survey: Proof of Concept
Henning, Thomas; Nakagawa, Takao; Currie, Thayne +24 more
Detailed chemical analyses of M dwarfs are scarce but necessary to constrain the formation environment and internal structure of planets being found around them. We present elemental abundances of 13 M dwarfs (2900 < T eff < 3500 K) observed in the Subaru/IRD planet search project. They are mid- to late-M dwarfs whose abundance of…
Mass Production of 2021 KMTNet Microlensing Planets. I
Han, Cheongho; Lee, Chung-Uk; Zang, Weicheng +17 more
We inaugurate a program of "mass production" of microlensing planets discovered in 2021 KMTNet data, with the aim of laying the basis for future statistical studies. While we ultimately plan to quickly publish all 2021 planets meeting some minimal criteria, the current sample of four was chosen simply on the basis of having low initial estimates o…