TY - JOUR
T1 - Extended neutral hydrogen filamentary network in NGC 2403
AU - Veronese, Simone
AU - De Blok, W. J.G.
AU - Walter, F.
N1 - Funding Information:
We would like to thank A. Fergusson for providing us with the stellar catalogue from Barker et al. 2012. We thank F. Fraternali for the useful discussions about the interpretation of our results and F. Maccagni for the initial discussions on the DDO 44 optical data. A. Marasco’s help in the modelling of our data is gratefully acknowledged. Also, we thank J. Carlin for kindly sharing with us the new re-reduced optical data of DDO 44. We thank the anonymous referee for the constructive comments and the suggested improvements for the quality and clarity of this paper. This work has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement No 882793 ‘MeerGas’).
Funding Information:
We would like to thank A. Fergusson for providing us with the stellar catalogue from Barker et al. 2012. We thank F. Fraternali for the useful discussions about the interpretation of our results and F. Maccagni for the initial discussions on the DDO 44 optical data. A. Marasco's help in the modelling of our data is gratefully acknowledged. Also, we thank J. Carlin for kindly sharing with us the new re-reduced optical data of DDO 44.We thank the anonymous referee for the constructive comments and the suggested improvements for the quality and clarity of this paper. This work has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (grant agreement No 882793 'MeerGas').
Publisher Copyright:
© 2023 The Authors.
PY - 2023/4/1
Y1 - 2023/4/1
N2 - We present new neutral hydrogen (H I) observations of the nearby galaxy NGC 2403 to determine the nature of a low-column-density cloud that was detected earlier by the Green Bank Telescope. We find that this cloud is the tip of a complex of filaments of extraplanar gas that is coincident with the thin disk. The total H I mass of the complex is 2 × 107 M⊙ or 0.6% of the total H I mass of the galaxy. The main structure, previously referred to as the 8 kpc filament, is now seen to be even more extended, along a 20 kpc stream. The kinematics and morphological properties of the filaments are unlikely to be the result of outflows related to galactic fountains. It is more likely that the 20 kpc filament is related to a recent galaxy interaction. In this context, a ∼50 kpc long stellar stream has recently been detected connecting NGC 2403 with the nearby dwarf satellite DDO 44. Intriguingly, the southern edge of this stream overlaps with the tip of the 20 kpc H I filament. We conclude that the H I anomalies in NGC 2403 are the result of a recent (∼2Gyr) interaction with DDO 44 leading to the observed filamentary complex.
AB - We present new neutral hydrogen (H I) observations of the nearby galaxy NGC 2403 to determine the nature of a low-column-density cloud that was detected earlier by the Green Bank Telescope. We find that this cloud is the tip of a complex of filaments of extraplanar gas that is coincident with the thin disk. The total H I mass of the complex is 2 × 107 M⊙ or 0.6% of the total H I mass of the galaxy. The main structure, previously referred to as the 8 kpc filament, is now seen to be even more extended, along a 20 kpc stream. The kinematics and morphological properties of the filaments are unlikely to be the result of outflows related to galactic fountains. It is more likely that the 20 kpc filament is related to a recent galaxy interaction. In this context, a ∼50 kpc long stellar stream has recently been detected connecting NGC 2403 with the nearby dwarf satellite DDO 44. Intriguingly, the southern edge of this stream overlaps with the tip of the 20 kpc H I filament. We conclude that the H I anomalies in NGC 2403 are the result of a recent (∼2Gyr) interaction with DDO 44 leading to the observed filamentary complex.
KW - Galaxies: evolution
KW - Galaxies: interactions
KW - Radio lines: galaxies
KW - Techniques: interferometric
UR - http://www.scopus.com/inward/record.url?scp=85153335482&partnerID=8YFLogxK
U2 - 10.1051/0004-6361/202245423
DO - 10.1051/0004-6361/202245423
M3 - Article
AN - SCOPUS:85153335482
SN - 0004-6361
VL - 672
JO - Astronomy and Astrophysics
JF - Astronomy and Astrophysics
M1 - A55
ER -