193 citations · 1.7k across the 44 of their papers we have counts for
44 papers
Impact of initial mass function on the chemical evolution of high-redshift galaxies
Boyuan Liu, Michela Mapelli, Volker Bromm +10
Recent observations by the James Webb Space Telescope (JWST) have found evidence for an invariant relation between stellar mass, metallicity, and star formation rate up to $z\sim 8…
A-SLOTH reveals the nature of the first stars
Tilman Hartwig, Veronika Lipatova, Simon C. O. Glover +1
The first generation of stars (PopIII) are too dim to be observed directly and probably too short-lived to have survived for local observations. Hence, we rely on simulations and i…
The imprint of the first stars on the faint end of the white dwarf luminosity function
Bartosz Dzięcioł, Tilman Hartwig, Naoki Yoshida
Population III stars are characterized by extremely low metallicities as they are thought to be formed from a pristine gas in the early Universe. Although the existence of Populati…
Gravitational waves from mergers of Population III binary black holes: roles played by two evolution channels
Boyuan Liu, Tilman Hartwig, Nina S. Sartorio +6
The gravitational wave (GW) signal from binary black hole (BBH) mergers is a promising probe of Population III (Pop III) stars. To fully unleash the power of the GW probe, one impo…
The Galaxy Assembly and Interaction Neural Networks (GAINN) for high-redshift JWST observations
Lillian Santos-Olmsted, Kirk Barrow, Tilman Hartwig
We present the Galaxy Assembly and Interaction Neural Networks (GAINN), a series of artificial neural networks for predicting the redshift, stellar mass, halo mass, and mass-weight…
Population III X-ray Binaries and their Impact on the Early Universe
Nina S. Sartorio, A. Fialkov, T. Hartwig +8
The first population of X-ray binaries (XRBs) is expected to affect the thermal and ionization states of the gas in the early Universe. Although these X-ray sources are predicted t…
Binary black hole mergers from Population III stars: uncertainties from star formation and binary star properties
Filippo Santoliquido, Michela Mapelli, Giuliano Iorio +5
Population III (Pop. III) binary stars likely produced the first stellar-born binary black hole (BBH) mergers in the Universe. Here, we quantify the main sources of uncertainty for…
Machine learning detects multiplicity of the first stars in stellar archaeology data
Tilman Hartwig, Miho N. Ishigaki, Chiaki Kobayashi +2
In unveiling the nature of the first stars, the main astronomical clue is the elemental compositions of the second generation of stars, observed as extremely metal-poor (EMP) stars…
First estimate of the local value of the baryonic streaming velocity
Betul Uysal, Tilman Hartwig
Several studies have shown the influence of the relative streaming velocity (SV) between baryons and dark matter on the formation of structures. For the first time, we constrain th…
A machine learning approach to assessing the presence of substructure in quasar host galaxies using the Hyper Suprime-Cam Subaru Strategic Program
Chris Nagele, John D. Silverman, Tilman Hartwig +4
The conditions under which galactic nuclear regions become active are largely unknown, although it has been hypothesized that secular processes related to galaxy morphology could p…
A-SLOTH: Ancient Stars and Local Observables by Tracing Halos
Mattis Magg, Tilman Hartwig, Li-Hsin Chen +1
Galaxies are thought to reside inside of large gravitationally bound structures of dark matter, so-called haloes. While the smallest of these haloes host no or only a few stars, th…
Unveiling the contribution of Pop III stars in primeval galaxies at redshift
Shafqat Riaz, Tilman Hartwig, Muhammad A. Latif
Detection of the first stars has remained elusive so-far but their presence may soon be unveiled by upcoming JWST observations. Previous studies have not investigated the entire po…
Comparing simulated Milky Way satellite galaxies with observations using unsupervised clustering
Li-Hsin Chen, Tilman Hartwig, Ralf S. Klessen +1
We develop a new analysis method that allows us to compare multi-dimensional observables to a theoretical model. The method is based on unsupervised clustering algorithms which ass…
Fast optical flares from M dwarfs detected by a one-second-cadence survey with Tomo-e Gozen
Masataka Aizawa, Kojiro Kawana, Kazumi Kashiyama +18
We report a one-second-cadence wide-field survey for M-dwarf flares using the Tomo-e Gozen camera mounted on the Kiso Schmidt telescope. We detect 22 flares from M3-M5 dwarfs with…
Public Release of A-SLOTH: Ancient Stars and Local Observables by Tracing Halos
Tilman Hartwig, Mattis Magg, Li-Hsin Chen +8
The semi-analytical model A-SLOTH (Ancient Stars and Local Observables by Tracing Halos) is the first public code that connects the formation of the first stars and galaxies to obs…
Tracing stars in Milky Way satellites with A-SLOTH
Li-Hsin Chen, Mattis Magg, Tilman Hartwig +3
We study the stellar mass-to-halo mass relation at in 30 Milky Way-like systems down to the ultra-faint () regime using the semi-analytic model A-SLOTH. A…
Effect of the cosmological transition to metal-enriched star-formation on the hydrogen 21-cm signal
Mattis Magg, Itamar Reis, Anastasia Fialkov +6
Mapping Cosmic Dawn with 21-cm tomography offers an exciting new window into the era of primordial star formation. However, self-consistent implementation of both the process of st…
Gravitational waves from the remnants of the first stars in nuclear star clusters
Boyuan Liu, Volker Bromm
We study Population III (Pop III) binary remnant mergers in nuclear star clusters (NSCs) with a semi-analytical approach for early structure formation. Within this framework, we ke…
Origin of metals in old Milky Way halo stars based on GALAH and Gaia
Miho N. Ishigaki, Tilman Hartwig, Yuta Tarumi +6
Stellar and supernova nucleosynthesis in the first few billion years of the cosmic history have set the scene for early structure formation in the Universe, while little is known a…
Optical Spectroscopy of Dual Quasar Candidates from the Subaru HSC-SSP program
Shenli Tang, John D. Silverman, Xuheng Ding +30
We report on a spectroscopic program to search for dual quasars using Subaru Hyper Suprime-Cam (HSC) images of SDSS quasars which represent an important stage during galaxy mergers…
Metal-Poor Stars Observed with the Southern African Large Telescope
Kaitlin C. Rasmussen, Joseph Zepeda, Timothy C. Beers +5
We present the first release of a large-scale study of relatively bright (V < 13.5) metal-poor stars observed with the Southern African Large Telescope (SALT), based on high-resolu…
Dual supermassive black holes at close separation revealed by the Hyper Suprime-Cam Subaru Strategic Program
John D. Silverman, Shenli Tang, Khee-Gan Lee +30
The unique combination of superb spatial resolution, wide-area coverage, and deep depth of the optical imaging from the Hyper Suprime-Cam (HSC) Subaru Strategic Program is utilized…
Neural Networks Fail to Learn Periodic Functions and How to Fix It
Liu Ziyin, Tilman Hartwig, Masahito Ueda
Previous literature offers limited clues on how to learn a periodic function using modern neural networks. We start with a study of the extrapolation properties of neural networks;…
Implications of inhomogeneous metal mixing for stellar archaeology
Yuta Tarumi, Tilman Hartwig, Mattis Magg
The first supernovae enrich the previously pristine gas with metals, out of which the next generation of stars form. Based on hydrodynamical simulations, we develop a new stochasti…