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Browsing by Author "Hartke, Johanna"
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The Andromeda Galaxy’s Last Major Merger: Constraints from the survey of Planetary Nebulae
Bhattacharya, Souradeep; Arnaboldi, Magda; Gerhard, Ortwin; Caldwell, Nelson; Kobayashi, Chiaki; Hammer, Francois; Yang, Yanbin; Freeman, Kenneth C.; Hartke, Johanna; McConnachie, Alan (The International Astronomical Union, 2023-05-04)The Andromeda galaxy (M 31) has experienced a tumultuous merger history as evidenced by the many substructures present in its inner halo. We use planetary nebulae (PNe) as chemodynamic tracers to shed light on the recent ... -
The survey of planetary nebulae in Andromeda (M 31) V. Chemical enrichment of the thin and thicker discs of Andromeda. Oxygen to argon abundance ratios for planetary nebulae and H II regions
Arnaboldi, Magda; Bhattacharya, Souradeep; Gerhard, Ortwin; Kobayashi, Chiaki; Freeman, Kenneth C.; Caldwell, Nelson; Hartke, Johanna; McConnachie, Alan; Guhathakurta, Puragra (2022-10-13)We use oxygen and argon abundances for planetary nebulae (PNe) with low internal extinction (progenitor ages of (>4.5 Gyr) and high extinction (progenitor ages -
The survey of planetary nebulae in Andromeda (M31). IV. Radial oxygen and argon abundance gradients of the thin and thicker disc
Bhattacharya, Souradeep; Arnaboldi, Magda; Caldwell, Nelson; Gerhard, Ortwin; Kobayashi, Chiaki; Hartke, Johanna; Freeman, Kenneth C.; McConnachie, Alan W.; Guhathakurta, Puragra (2022-12-01)We obtain a magnitude-limited sample of Andromeda (M 31) disc PNe with chemical abundance estimated through the direct detection of the [O III] 4363 Å line. This leads to 205 and 200 PNe with oxygen and argon abundances, ...