Search Publications

Reanalysis of the MACHO Constraints on PBH in the Light of Gaia DR3 Data
DOI: 10.3390/universe10120449 Bibcode: 2024Univ...10..449G

García-Bellido, Juan; Hawkins, Michael

The recent astrometric data of hundreds of millions of stars from Gaia DR3 has allowed for a precise determination of the Milky Way rotation curve up to 28 kpc. The data suggest a rapid decline in the density of dark matter beyond 19 kpc. We fit the whole rotation curve with four components (gas, disk, bulge, and halo), and compute the microlensin…

2024 Universe
Gaia 7
The Magellanic Clouds Are Very Rare in the IllustrisTNG Simulations
DOI: 10.3390/universe10100385 Bibcode: 2024Univ...10..385H

Kroupa, Pavel; Haslbauer, Moritz; Banik, Indranil +2 more

The Large and Small Magellanic Clouds (LMC and SMC) form the closest interacting galactic system to the Milky Way, therewith providing a laboratory to test cosmological models in the local Universe. We quantify the likelihood for the Magellanic Clouds (MCs) to be observed within the

2024 Universe
Gaia 3
Modeling the TESS Light Curve of Ap Si Star MX TrA
DOI: 10.3390/universe10090341 Bibcode: 2024Univ...10..341P

Pakhomov, Yury; Potravnov, Ilya; Romanovskaya, Anna +1 more

The TESS light curve of the silicon Ap star MX TrA was modeled using the observational surface distribution of silicon, iron, helium, and chromium obtained previously with the Doppler Imaging technique. The theoretical light curve was calculated using a grid of synthetic fluxes from line-by-line stellar atmosphere models with individual chemical a…

2024 Universe
Gaia 1
Study of Nonlinear Evolution of Spacetime Fluctuations in Quantum Gravity Inflation for Deriving Primordial Spectrum
DOI: 10.3390/universe10010033 Bibcode: 2024Univ...10...33H

Hamada, Ken-ji

We study the evolution of quantum fluctuations of gravity around an inflationary solution in renormalizable quantum gravity, in which the initial scalar-fluctuation dominance is shown by the background-free nature expressed by a special conformal invariance. Inflation ignites at the Planck scale and continues until spacetime phase transition occur…

2024 Universe
Gaia 0
X-Ray Views of Galactic Accreting Pulsars in High-Mass X-Ray Binaries
DOI: 10.3390/universe10120453 Bibcode: 2024Univ...10..453W

Weng, Shan-Shan; Ji, Long

Accreting X-ray pulsars, located in X-ray binaries, are neutron stars with magnetic fields as strong as B101213

2024 Universe
Gaia 0
The Property of the Gaia Celestial Reference Frame 3 (Gaia-CRF3)
DOI: 10.3390/universe10120455 Bibcode: 2024Univ...10..455L

Liu, Guangyi; Guo, Sufen

With the release of Gaia DR3, evaluating the performance and consistency of its reference frame (Gaia-CRF3) with the International Celestial Reference Frame (ICRF3) has become a critical task. Gaia-CRF3 serves as the second non-rotating inertial reference frame in the optical wavelength for the implementation of the International Celestial Referen…

2024 Universe
Gaia 0
Disk Evolution Study Through Imaging of Nearby Young Stars (DESTINYS): Dynamical Evidence of a Spiral-Arm-Driving and Gap-Opening Protoplanet from SAO 206462 Spiral Motion
DOI: 10.3390/universe10120465 Bibcode: 2024Univ...10..465X

Ren, Bin B.; Ménard, François; Bae, Jaehan +8 more

In the early stages of planetary system formation, young exoplanets gravitationally interact with their surrounding environments and leave observable signatures on protoplanetary disks. Among these structures, a pair of nearly symmetric spiral arms can be driven by a giant protoplanet. For the double-spiraled SAO 206462 protoplanetary disk, we obt…

2024 Universe
Gaia 0
Observational Detection of Higher-Order Secular Perturbations in Tight Hierarchical Triple Stars
DOI: 10.3390/universe9110485 Bibcode: 2023Univ....9..485B

Borkovits, Tamás; Mitnyan, Tibor

In this work, we search for observational evidence of higher-order secular perturbations in three eclipsing binaries. These are slightly eccentric binaries, and they form the inner pairs of tight, compact, hierarchical triple star systems. Simultaneously, we analyze the high-precision satellite (Kepler and TESS) light curves; eclipse timing variat…

2023 Universe
Gaia 7
The Purport of Space Telescopes in Supernova Research
DOI: 10.3390/universe9060244 Bibcode: 2023Univ....9..244V

Vinkó, József; Könyves-Tóth, Réka; Szalai, Tamás

The violent stellar explosions known as supernovae have received especially strong attention in both the research community and the general public recently. With the advent of space telescopes, the study of these extraordinary events has switched gears and it has become one of the leading fields in modern astrophysics. In this paper, we review som…

2023 Universe
Gaia 5
Oort Constants and Local Stellar Kinematics from GCNS
DOI: 10.3390/universe9060252 Bibcode: 2023Univ....9..252G

Qi, Zhaoxiang; Guo, Sufen

Oort constants and local kinematics are vital parameters with which to study the structure and dynamics of the Milky Way. When GCNS was published, it provided a clean sample of stars in the solar vicinity, which gives us an ideal tool with which to determine these parameters. Our aim was to calculate the reliable Oort constants with GCNS. We deter…

2023 Universe
Gaia 4