Praesepe (NGC 2632) and its tidal tails
Aims. Within a 400 pc sphere around the Sun, we search for Praesepe’s tidal tails in the Gaia Data Release 2 (DR2) data set. Methods. We used a modified convergent-point method to find stars with space velocities close to the space velocity of the Praesepe cluster. Results. We find a clear indicatio...
Saved in:
| Main Authors: | , |
|---|---|
| Format: | Article (Journal) |
| Language: | English |
| Published: |
16 April 2019
|
| In: |
Astronomy and astrophysics
Year: 2019, Volume: 627 |
| ISSN: | 1432-0746 |
| DOI: | 10.1051/0004-6361/201935502 |
| Online Access: | Verlag, Volltext: https://doi.org/10.1051/0004-6361/201935502 Verlag, Volltext: https://www.aanda.org/articles/aa/abs/2019/07/aa35502-19/aa35502-19.html 
|
| Author Notes: | Siegfried Röser and Elena Schilbach |
| Summary: | Aims. Within a 400 pc sphere around the Sun, we search for Praesepe’s tidal tails in the Gaia Data Release 2 (DR2) data set. Methods. We used a modified convergent-point method to find stars with space velocities close to the space velocity of the Praesepe cluster. Results. We find a clear indication for the existence of Praesepe’s tidal tails, both extending up to 165 pc from the centre of the cluster. A total of 1393 stars populate the cluster and its tails, giving a total mass of 794 M⊙. We determined a tidal radius of 10.77 pc for the cluster and a tidal mass of 483 M⊙. The corresponding half-mass radius is 4.8 pc. We also found a clear indication for mass segregation in the cluster. The tidal tails outside 2 tidal radii are populated by 389 stars. The total contamination of our sample by field stars lies between 50 and 100 stars or 3.6–7.2%. We used an astrometrically and photometrically clean subsample of Gaia DR2, which makes our Praesepe sample incomplete beyond MG ≈ 12.0 mag; this corresponds to about 0.25 M⊙. A comparison with an N-body model of the cluster and its tails shows remarkably good coincidence. Three new white dwarfs are found in the tails. |
|---|---|
| Item Description: | Gesehen am 05.08.2019 |
| Physical Description: | Online Resource |
| ISSN: | 1432-0746 |
| DOI: | 10.1051/0004-6361/201935502 |