Results 41 to 50 of about 406 (178)

The Samples and Binary Fractions of Red Supergiants in M31 and M33 by the HST Observations

The Astrophysical Journal
The binarity of red supergiants (RSGs) influences their evolution and the fate of supernovae. We investigate the binary fraction of RSGs in the Andromeda galaxy (M31) and Triangulum galaxy (M33) using photometry from the Hubble Space Telescope (HST ...
Min Dai, Shu Wang, Biwei Jiang, Ying Li
doaj   +1 more source

Mass modelling the Andromeda Dwarf Galaxies: Andromeda VI and Andromeda XXIII

Monthly Notices of the Royal Astronomical Society
ABSTRACT Accurately mapping the mass profiles of low mass dwarf spheroidal (dSph) galaxies allows us to test predictions made by dark matter (DM) models. To date, such analyses have primarily been performed on Milky Way (MW) satellites.
Connor S Pickett, Michelle L M Collins, R Michael Rich, Justin I Read, Emily J E Charles, Nicolas Martin, Scott Chapman, Alan McConnachie, Alessandro Savino, Daniel R Weisz   +9 more
openaire   +4 more sources

Anxiety and Evidence

Philosophical Issues, Volume 35, Issue 1, Page 17-28, October 2025.
ABSTRACT When does an agent possess a proposition P as evidence? According to Timothy Williamson, the answer is when, and only when, they know that P. Call this view E = K. In this article, I point out an unwanted consequence of E = K, which is that people who suffer from anxiety have impoverished empirical evidence due to their anxiety.
Rhys Borchert
wiley   +1 more source

The Isaac Newton Telescope Monitoring Survey of Local Group Dwarf Galaxies. VIII. A Census of Long-period Variable Stars across the Andromeda Dwarf Satellite System

The Astrophysical Journal
We present a comprehensive catalog, in the Sloan i and Harris V filters, of long-period variable (LPV) stars in the spheroidal dwarf satellites of the Andromeda galaxy based on a dedicated survey for variable stars in Local Group dwarf systems.
Hedieh Abdollahi, Atefeh Javadi, Jacco Th. van Loon, Iain McDonald, Mahdi Abdollahi, Elham Saremi, Habib G. Khosroshahi, László Molnár, Hamidreza Mahani   +8 more
doaj   +1 more source

Molecular gas in the Andromeda galaxy [PDF]

Astronomy & Astrophysics, 2006
We present a new 12CO(J=1-0)-line survey of the Andromeda galaxy, M31, covering the bright disk with the highest resolution to date (85 pc along the major axis), observed On-the-Fly (in italics) with the IRAM 30-m telescope. We discuss the distribution of the CO emission and compare it with the distributions of HI and emission from cold dust traced at ...
Nieten, Ch., Neininger, N., Guelin, M., Ungerechts, H., Lucas, R., Berkhuijsen, E. M., Beck, R., Wielebinski, R.   +7 more
openaire   +2 more sources

Redshift‐Agnostic Machine Learning Classification: Unveiling Peak Performance in Galaxy, Star, and Quasar Classification (Using SDSS DR17)

Astronomische Nachrichten, Volume 346, Issue 5, June 2025.
ABSTRACT Classification of galaxies, stars, and quasars using spectral data is fundamental to astronomy, but often relies heavily on redshift. This study evaluates the performance of 10 machine learning algorithms on SDSS data to classify these objects, with a particular focus on scenarios where redshift information is unavailable.
Debashis Chatterjee, Prithwish Ghosh
wiley   +1 more source

Resolved SPLASH Chemodynamics in Andromeda’s PHAT Stellar Halo and Disk: On the Nature of the Inner Halo along the Major Axis

The Astronomical Journal, 2023
Stellar kinematics and metallicity are key to exploring formation scenarios for galactic disks and halos. In this work, we characterized the relationship between kinematics and photometric metallicity along the line of sight to M31's disk.
Ivanna Escala, Amanda C. N. Quirk, Puragra Guhathakurta, Karoline M. Gilbert, J. Leigh Wojno, Lara Cullinane, Benjamin F. Williams, Julianne Dalcanton   +7 more
doaj   +1 more source

Probing the Disk Kinematics of M31 with DESI

Edinburgh Student Journal of Science
M31’s stellar rotation curve and disk line-of-sight dispersion is presented using kinematic data from a novel DESI M31 survey in combination with similar datasets.
Struan Stevenson
doaj   +1 more source

On the α/Fe Bimodality of the M31 Disks

The Astrophysical Journal Letters, 2023
An outstanding question is whether the α /Fe bimodality exists in disk galaxies other than in the Milky Way. Here we present a bimodality using our state-of-the-art galactic chemical evolution models that can explain various observations in the Andromeda
Chiaki Kobayashi, Souradeep Bhattacharya, Magda Arnaboldi, Ortwin Gerhard   +3 more
doaj   +1 more source

Joint Constraints on Fuzzy and Warm Dark Matter from Satellite Populations of the Milky Way and Andromeda

The Astrophysical Journal
We perform a joint analysis of the Milky Way (MW) and Andromeda (M31) satellite populations to constrain the properties of fuzzy dark matter (FDM) and thermal-relic warm dark matter (WDM).
Jianxiang Liu, Yan Gong, Kai Liao
doaj   +1 more source