The pristine Dwarf-Galaxy survey - V. The edges of the dwarf galaxy hercules - INSU - Institut national des sciences de l'Univers Accéder directement au contenu
Article Dans Une Revue Monthly Notices of the Royal Astronomical Society Année : 2023

The pristine Dwarf-Galaxy survey - V. The edges of the dwarf galaxy hercules

Nicolas Longeard
  • Fonction : Auteur
Giuseppina Battaglia
  • Fonction : Auteur
Khyati Malhan
  • Fonction : Auteur
Rubén Sánchez-Janssen
  • Fonction : Auteur
Federico Sestito
  • Fonction : Auteur
Else Starkenburg
  • Fonction : Auteur
Kim A. Venn
  • Fonction : Auteur

Résumé

We present a new spectroscopic study of 175 stars in the vicinity of the dwarf galaxy Hercules (d ~132 kpc) with data from the Anglo-Australian Telescope and its AAOmega spectrograph together with the Two Degree Field multi-object system to solve the conundrum that whether Hercules is tidally disrupting. We combine broadband photometry, proper motions from Gaia, and our Pristine narrow-band and metallicity-sensitive photometry to efficiently weed out the Milky Way contamination. Such cleaning is particularly critical in this kinematic regime, as both the transverse and heliocentric velocities of Milky Way populations overlap with Hercules. Thanks to this method, three new member stars are identified, including one at almost 10rh of the satellite. All three have velocities and metallicities consistent with that of the main body. Combining this new dataset with the entire literature cleaned out from contamination shows that Hercules does not exhibit a velocity gradient (d/dχ $= 0.1^{+0.4}_{-0.2}$ km s-1 arcmin-1, 1.6 km s-1 arcmin-1 as a 3σ upper limit) and, as such, does not show evidence to undergo tidal disruption.
Fichier principal
Vignette du fichier
stad2227.pdf (2.42 Mo) Télécharger le fichier
Origine : Fichiers éditeurs autorisés sur une archive ouverte
Licence : CC BY - Paternité

Dates et versions

insu-04198344 , version 1 (05-01-2024)

Identifiants

Citer

Nicolas Longeard, Pascale Jablonka, Giuseppina Battaglia, Khyati Malhan, Nicolas Martin, et al.. The pristine Dwarf-Galaxy survey - V. The edges of the dwarf galaxy hercules. Monthly Notices of the Royal Astronomical Society, 2023, ⟨10.1093/mnras/stad2227⟩. ⟨insu-04198344⟩
40 Consultations
6 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More