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Andromeda's Parachute: Time Delays and Hubble Constant
DOI: 10.3847/1538-4357/acee7e Bibcode: 2023ApJ...955..140S

Dahle, Håkon; Goicoechea, Luis J.; Shalyapin, Vyacheslav N. +1 more

The gravitational lens system PS J0147+4630 (Andromeda's Parachute) consists of four quasar images ABCD and a lensing galaxy. We obtained r-band light curves of ABCD in the 2017-2022 period from monitoring with two 2 m class telescopes. Applying state-of-the-art curve-shifting algorithms to these light curves led to measurements of time delays bet…

2023 The Astrophysical Journal
eHST 3
Dynamical Response of Solar Wind Charge Exchange Soft X-Ray Emission in Earth's Magnetosphere to the Solar Wind Proton Flux
DOI: 10.3847/1538-4357/acc326 Bibcode: 2023ApJ...948...69Z

Ji, Li; Wang, Chi; Liu, Wenhao +5 more

This work studies the dynamic response of solar wind charge exchange (SWCX) soft X-ray emission in the Earth's magnetosphere to the solar wind proton flux. Unlike previous studies that attempted to use complex magnetohydrodynamic models to match the details of observed SWCX of a necessarily limited number of cases, this work focuses on determining…

2023 The Astrophysical Journal
XMM-Newton 3
A Survey of Strong Electric Potential Drops in the Ionosphere of Venus
DOI: 10.1029/2023GL104989 Bibcode: 2023GeoRL..5004989C

Zhang, Tielong; Futaana, Yoshifumi; Collinson, Glyn A. +6 more

Every planet or moon with an ionosphere is thought to generate a weak electrical potential which helps ions overcome gravity and escape to space. A pilot study at Venus by Collinson et al. (2016, https://doi.org/10.1002/2016GL068327) indicated a planetary potential an order of magnitude stronger t…

2023 Geophysical Research Letters
VenusExpress 3
Study of structural parameters and systemic proper motion of Sextans dwarf spheroidal galaxy with Subaru Hyper Suprime-Cam data
DOI: 10.1093/mnras/stad2422 Bibcode: 2023MNRAS.526.1310T

Komiyama, Yutaka; Takada, Masahiro; Hayashi, Kohei +4 more

We use the Subaru Hyper Suprime-Cam (HSC) data to study structural parameters and systemic proper motion of the Sextans dwarf spheroidal galaxy at the heliocentric distance of 86 kpc, which is one of the most important targets for studies of dark matter nature and galaxy formation physics. Thanks to the superb image quality and wide area coverage,…

2023 Monthly Notices of the Royal Astronomical Society
Gaia 3
Dust giant: Extended and clumpy star-formation in a massive dusty galaxy at z = 1.38
DOI: 10.1051/0004-6361/202346937 Bibcode: 2023A&A...677A.172K

Trebitsch, Maxime; Daddi, Emanuele; Liu, Daizhong +8 more

We present NOEMA CO (2-1) line and ALMA 870 µm continuum observations of a main-sequence galaxy at z = 1.38. The galaxy was initially deemed a "gas giant" based on the gas mass derived from sub-mm continuum (log(Mgas/M) = 11.20 ± 0.20), however, the gas mass derived from CO (2−1) luminosity brings the gas mass value down to …

2023 Astronomy and Astrophysics
eHST 3
Tidal debris from Omega Centauri discovered with unsupervised machine learning
DOI: 10.1093/mnras/stad1952 Bibcode: 2023MNRAS.524.2630Y

Lind, Karin; Kushniruk, Iryna; Youakim, Kris

The gravitational interactions between the Milky Way and in-falling satellites offer a wealth of information about the formation and evolution of our Galaxy. In this paper, we explore the high-dimensionality of the GALAH DR3 plus Gaia eDR3 data set to identify new tidally stripped candidate stars of the nearby star cluster Omega Centauri ($\omega …

2023 Monthly Notices of the Royal Astronomical Society
Gaia 3
ALMA Survey of Orion Planck Galactic Cold Clumps (ALMASOP): The Warm-envelope Origin of Hot Corinos
DOI: 10.3847/1538-4357/acefcf Bibcode: 2023ApJ...956..120H

Sanhueza, Patricio; Kwon, Woojin; Chen, Huei-Ru Vivien +24 more

Hot corinos are of great interest due to their richness in interstellar complex organic molecules (COMs) and the consequent potential prebiotic connection to solar-like planetary systems. Recent surveys have reported an increasing number of detected hot corinos in Class 0/I protostars; however, the relationships between their physical properties a…

2023 The Astrophysical Journal
AKARI 3
Identifying and characterising the population of hot sub-luminous stars with multi-colour MeerLICHT data
DOI: 10.1051/0004-6361/202245560 Bibcode: 2023A&A...672A..69R

Groot, P. J.; Aerts, C.; Ranaivomanana, P. +9 more

Context. Colour-magnitude diagrams reveal a population of blue (hot) sub-luminous objects with respect to the main sequence. These hot sub-luminous stars are the result of evolutionary processes that require stars to expel their obscuring, hydrogen-rich envelopes to reveal the hot helium core. As such, these objects offer a direct window into the …

2023 Astronomy and Astrophysics
Gaia 3
A search for missing radio sources at z ≳ 4 using Lyman dropouts
DOI: 10.1093/mnras/stac3319 Bibcode: 2023MNRAS.519.4902S

Norris, Ray P.; Hopkins, Andrew M.; Shabala, Stanislav S. +5 more

Using the Lyman Dropout technique, we identify 148 candidate radio sources at z ≳ 4-7 from the 887.5 MHz Australian Square Kilometre Array Pathfinder (ASKAP) observations of the GAMA23 field. About 112 radio sources are currently known beyond redshift z ~ 4. However, simulations predict that hundreds of thousands of radio sources exist in that red…

2023 Monthly Notices of the Royal Astronomical Society
Gaia Herschel 3
Predicting light curves of RR Lyrae variables using artificial neural network based interpolation of a grid of pulsation models
DOI: 10.1093/mnras/stad937 Bibcode: 2023MNRAS.522.1504K

Marconi, Marcella; Das, Susmita; Kanbur, Shashi M. +4 more

We present a new technique to generate the light curves of RRab stars in different photometric bands (I and V bands) using artificial neural networks (ANN). A pre-computed grid of models was used to train the ANN, and the architecture was tuned using the I-band light curves. The best-performing network was adopted to make the final interpolators i…

2023 Monthly Notices of the Royal Astronomical Society
Gaia 3