Search Publications

On the Formation of Planets in the Milky Way's Thick Disk
DOI: 10.3847/1538-4357/ad9aa1 Bibcode: 2025ApJ...979..120H

Lee, Eve J.; Hallatt, Tim

Exoplanet demographic surveys have revealed that close-in (≲1 au) small planets orbiting stars in the Milky Way's thick disk are ∼50% less abundant than those orbiting stars in the Galactic thin disk. One key difference between the two stellar populations is the time at which they emerged: thick-disk stars are the likely product of cosmic noon (re…

2025 The Astrophysical Journal
Gaia 4
Internal dynamics of multiple populations in 28 Galactic globular clusters: a wide-field study with Gaia and the Hubble Space Telescope
DOI: 10.1093/mnras/staf102 Bibcode: 2025MNRAS.537.2342C

Milone, A. P.; Cordoni, G.; Marino, A. F. +13 more

We present a detailed analysis of the internal dynamics of multiple stellar populations (MPs) in 28 Galactic globular clusters (GCs) across a wide field of view, extending from the innermost regions to the clusters' outskirts. Using astrophotometric catalogues from ground-based observations, Gaia and the Hubble Space Telescope (HST), we identify f…

2025 Monthly Notices of the Royal Astronomical Society
Gaia 4
Spatially coherent 3D distributions of HI and CO in the Milky Way
DOI: 10.1051/0004-6361/202451361 Bibcode: 2025A&A...693A.139S

Edenhofer, Gordian; Mertsch, Philipp; Söding, Laurin +6 more

Context. The spatial distribution of the gaseous components of the Milky Way is of great importance for a number of different fields, for example, Galactic structure, star formation, and cosmic rays. However, obtaining distance information to gaseous clouds in the interstellar medium from Doppler-shifted line emission is notoriously difficult give…

2025 Astronomy and Astrophysics
Gaia 4
Significant Mutual Inclinations Between the Stellar Spin and the Orbits of Both Planets in the HAT-P-11 System
DOI: 10.3847/1538-3881/ad90b4 Bibcode: 2025AJ....169...22A

Brandt, Timothy D.; Brandt, G. Mirek; Li, Gongjie +2 more

Planet–star obliquity and planet–planet mutual inclination encode a planetary system's dynamical history, but both of their values are hard to measure for misaligned systems with close-in companions. HAT-P-11 is a K4 star with two known planets: a close-in, misaligned super-Neptune with a ≈5 day orbit, and an outer super-Jupiter with a ≈10 yr orbi…

2025 The Astronomical Journal
Gaia 4
Detection of the [O I] 63 µm emission line from the z = 6.04 quasar J2054-0005
DOI: 10.1093/pasj/psae105 Bibcode: 2025PASJ...77..139I

Fujimoto, Seiji; Inoue, Akio K.; Hashimoto, Takuya +23 more

We report the highest-redshift detection of [O I] 63 $\mu$m from a luminous quasar, J2054$-$0005, at $z=6.04$

2025 Publications of the Astronomical Society of Japan
ISO 4
Constraining Atmospheric Composition from the Outflow: Helium Observations Reveal the Fundamental Properties of Two Planets Straddling the Radius Gap
DOI: 10.3847/1538-3881/adb490 Bibcode: 2025AJ....169..204Z

Knutson, Heather A.; Horne, Keith; Collins, Karen A. +13 more

TOI-836 is a ∼2–3 Gyr K dwarf with an inner super Earth (R = 1.7 R, P = 3.8 days) and an outer mini-Neptune (R = 2.6 R, P = 8.6 days). JWST/NIRSpec 2.8–5.2 µm transmission spectra are flat for both planets. We present Keck/NIRSPEC observations of escaping helium for super-Earth b, which shows no excess absorption in t…

2025 The Astronomical Journal
XMM-Newton 4
Representation learning for time-domain high-energy astrophysics: Discovery of extragalactic fast X-ray transient XRT 200515
DOI: 10.1093/mnras/stae2808 Bibcode: 2025MNRAS.537..931D

Soria, Roberto; Kashyap, Vinay L.; Martínez-Galarza, Juan Rafael +2 more

We present a novel representation learning method for downstream tasks like anomaly detection, unsupervised classification, and similarity searches in high-energy data sets. This enabled the discovery of a new extragalactic fast X-ray transient (FXT) in Chandra archival data, XRT 200515, a needle-in-the-haystack event and the first Chandra FXT of …

2025 Monthly Notices of the Royal Astronomical Society
Gaia 4
Testing the Breakdown of the Asteroseismic Scaling Relations in Luminous Red Giants
DOI: 10.3847/1538-4357/ad9b18 Bibcode: 2025ApJ...979..135A

Pinsonneault, Marc H.; Vrard, Mathieu; Zinn, Joel C. +1 more

Nearly all cool, evolved stars are solar-like oscillators, and fundamental stellar properties can be inferred from these oscillations with asteroseismology. Scaling relations are commonly used to relate global asteroseismic properties—the frequency of maximum power and the large-frequency separation Δν—to stellar…

2025 The Astrophysical Journal
Gaia 4
Characterization of a Peculiar Einstein Probe Transient EP240408a: An Exotic Gamma-Ray Burst or an Abnormal Jetted Tidal Disruption Event?
DOI: 10.3847/2041-8213/ada7f5 Bibcode: 2025ApJ...979L..30O

Buckley, David; Cenko, S. Bradley; Klingler, Noel +30 more

We present the results of our multiwavelength (X-ray to radio) follow-up campaign of the Einstein Probe transient EP240408a. The initial 10 s trigger displayed bright soft X-ray (0.5–4 keV) radiation with peak luminosity LX ≳ 1049 (1050) erg s‑1 for an assumed redshift z ≳ 0.5 (2.0). The Neil Gehrels Swi…

2025 The Astrophysical Journal
XMM-Newton 4
Primordial black holes in SB SUSY Gauss-Bonnet inflation
DOI: 10.1088/1475-7516/2025/01/025 Bibcode: 2025JCAP...01..025A

Ashrafzadeh, A.; Solbi, M.; Heydari, S. +1 more

Here, we explore the formation of primordial black holes (PBHs) within a scalar field inflationary model coupled to the Gauss-Bonnet (GB) term, incorporating the low-scale spontaneously broken supersymmetric (SB SUSY) potential. The coupling function amplifies the curvature perturbations, consequently leading to the formation of PBHs and detectabl…

2025 Journal of Cosmology and Astroparticle Physics
INTEGRAL 4