165 citations · 610 across the 22 of their papers we have counts for
24 papers
Impact of Gaia-Sausage-Enceladus merger revealed by a single cosmic clock: thick-to-thin disc transition, gas disc shrinking and bar formation
Natsuki Funakoshi, Daisuke Kawata, Jason L. Sanders +5
Whether the formation of the Galactic bar was connected to the Gaia-Sausage-Enceladus (GSE) merger, the last significant merger experienced by the Milky Way, remains an open questi…
High-fidelity stellar extinction with Gaia and APOGEE -- I. The method and a new extinction curve
Jie Yu, Luca Casagrande, John A. Taylor +9
The scarcity of high-fidelity extinction measurements remains a bottleneck in deriving accurate stellar properties from Gaia parallaxes. In this work, we aim to derive precision ex…
Thick-to-thin disc transition and gas disc shrinking induced by the Gaia-Sausage-Enceladus merger
Natsuki Funakoshi, Daisuke Kawata, Jason L. Sanders +3
Understanding the Milky Way disc formation requires characterising its structural and kinematic properties as functions of stellar age. Using red giant stars from APOGEE DR17 and G…
Towards Galactic Archaeology with Inferred Ages of Giant Stars From Gaia Spectra
Aisha S. Almannaei, Daisuke Kawata, Ioana Ciuca +4
In the era of Gaia, the accurate determination of stellar ages is transforming Galactic archaeology. We demonstrate the feasibility of inferring stellar ages from Gaia's RVS spectr…
pathfinder: A Semantic Framework for Literature Review and Knowledge Discovery in Astronomy
Kartheik G. Iyer, Mikaeel Yunus, Charles O'Neill +27
The exponential growth of astronomical literature poses significant challenges for researchers navigating and synthesizing general insights or even domain-specific knowledge. We pr…
Cosmological evolution of metallicity correlation functions from the Auriga simulations
Zefeng Li, Robert J. J. Grand, Emily Wisnioski +7
We study the cosmological evolution of the two-point correlation functions of galactic gas-phase metal distributions using the 28 simulated galaxies from the Auriga Project. Using…
3D NLTE Lithium abundances for late-type stars in GALAH DR3
Ella Xi Wang, Thomas Nordlander, Sven Buder +7
Lithium's susceptibility to burning in stellar interiors makes it an invaluable tracer for delineating the evolutionary pathways of stars, offering insights into the processes gove…
AstroLLaMA-Chat: Scaling AstroLLaMA with Conversational and Diverse Datasets
Ernest Perkowski, Rui Pan, Tuan Dung Nguyen +11
We explore the potential of enhancing LLM performance in astronomy-focused question-answering through targeted, continual pre-training. By employing a compact 7B-parameter LLaMA-2…
Experimenting with Large Language Models and vector embeddings in NASA SciX
Sergi Blanco-Cuaresma, Ioana Ciucă, Alberto Accomazzi +19
Open-source Large Language Models enable projects such as NASA SciX (i.e., NASA ADS) to think out of the box and try alternative approaches for information retrieval and data augme…
AstroLLaMA: Towards Specialized Foundation Models in Astronomy
Tuan Dung Nguyen, Yuan-Sen Ting, Ioana Ciucă +21
Large language models excel in many human-language tasks but often falter in highly specialized domains like scholarly astronomy. To bridge this gap, we introduce AstroLLaMA, a 7-b…
Adversarial Fine-Tuning of Language Models: An Iterative Optimisation Approach for the Generation and Detection of Problematic Content
Charles O'Neill, Jack Miller, Ioana Ciuca +2
In this paper, we tackle the emerging challenge of unintended harmful content generation in Large Language Models (LLMs) with a novel dual-stage optimisation technique using advers…
Steering Language Generation: Harnessing Contrastive Expert Guidance and Negative Prompting for Coherent and Diverse Synthetic Data Generation
Charles O'Neill, Yuan-Sen Ting, Ioana Ciuca +2
Large Language Models (LLMs) hold immense potential to generate synthetic data of high quality and utility, which has numerous applications from downstream model training to practi…
Harnessing the Power of Adversarial Prompting and Large Language Models for Robust Hypothesis Generation in Astronomy
Ioana Ciucă, Yuan-Sen Ting, Sandor Kruk +1
This study investigates the application of Large Language Models (LLMs), specifically GPT-4, within Astronomy. We employ in-context prompting, supplying the model with up to 1000 p…
The outer low- disc of the Milky Way -- I: evidence for the first pericentric passage of Sagittarius?
Payel Das, Yang Huang, Ioana Ciuca +1
Phase-space data, chemistry, and ages together reveal a complex structure in the outer low- disc of the Milky Way. The age-vertical velocity dispersion profiles beyond the Solar…
Galactic ChitChat: Using Large Language Models to Converse with Astronomy Literature
Ioana Ciucă, Yuan-Sen Ting
We demonstrate the potential of the state-of-the-art OpenAI GPT-4 large language model to engage in meaningful interactions with Astronomy papers using in-context prompting. To opt…
Chasing the impact of the Gaia-Sausage-Enceladus merger on the formation of the Milky Way thick disc
Ioana Ciucă, Daisuke Kawata, Yuan-Sen Ting +8
We employ our Bayesian Machine Learning framework BINGO (Bayesian INference for Galactic archaeOlogy) to obtain high-quality stellar age estimates for 68,360 red giant and red clum…
Unsupervised Learning for Stellar Spectra with Deep Normalizing Flows
Ioana Ciuca, Yuan-Sen Ting
Stellar spectra encode detailed information about the stars. However, most machine learning approaches in stellar spectroscopy focus on supervised learning. We introduce Mendis, an…
The GALAH Survey: Chemical tagging and chrono-chemodynamics of accreted halo stars with GALAH+ DR3 and eDR3
Sven Buder, Karin Lind, Melissa K. Ness +27
Since the advent of astrometry, it is possible to identify massive accreted systems within the Galaxy through their unique dynamical signatures. One such system, -Saus…
Galactic Bar Resonances Inferred from Kinematically Hot Stars in Gaia EDR3
Daisuke Kawata, Junichi Baba, Jason A. S. Hunt +5
Using a numerical simulation of an isolated barred disc galaxy, we first demonstrate that the resonances of the inner bar structure induce more prominent features in the action spa…
Unveiling the Distinct Formation Pathways of the Inner and Outer Discs of the Milky Way with Bayesian Machine Learning
Ioana Ciucă, Daisuke Kawata, Andrea Miglio +2
We develop a Bayesian Machine Learning framework called BINGO (Bayesian INference for Galactic archaeOlogy) centred around a Bayesian neural network. After being trained on the APO…
Spectral and spatial analysis of the dark matter subhalo candidates among Fermi Large Area Telescope unidentified sources
Javier Coronado-Blázquez, Miguel A. Sánchez-Conde, Mattia Di Mauro +5
Fermi-LAT unidentified sources (unIDs) have proven to be compelling targets for performing indirect dark matter (DM) searches. In a previous work, we found that among the 1235 unID…
A Gaia DR2 search for dwarf galaxies towards Fermi-LAT sources: implications for annihilating dark matter
Ioana Ciucă, Daisuke Kawata, Shin'ichiro Ando +3
We make a first attempt to find dwarf galaxies in eight \Fermi-LAT extended, unassociated, source fields using \Gaia\ DR2. We probe previously unexplored heliocentric distances of…
Radial Distribution of Stellar Motions in Gaia DR2
Daisuke Kawata, Junichi Baba, Ioana Ciucă +4
By taking advantage of the superb measurements of position and velocity for an unprecedented large number of stars provided in Gaia DR2, we have generated the first maps of the rot…
Confirming chemical clocks: asteroseismic age dissection of the Milky Way disk(s)
V. Silva Aguirre, M. Bojsen-Hansen, D. Slumstrup +22
Investigations of the origin and evolution of the Milky Way disk have long relied on chemical and kinematic identification of its components to reconstruct our Galactic past. Diffi…