TY - JOUR
T1 - NGTS clusters survey. I. Rotation in the young benchmark open cluster Blanco 1
AU - Gillen, Edward
AU - Briegal, Joshua T.
AU - Hodgkin, Simon T.
AU - Foreman-Mackey, Daniel
AU - Van Leeuwen, Floor
AU - Jackman, James A. G.
AU - McCormac, James
AU - West, Richard G.
AU - Queloz, Didier
AU - Bayliss, Daniel
AU - Goad, Michael R.
AU - Watson, Christopher A.
AU - Wheatley, Peter J.
AU - Belardi, Claudia
AU - Burleigh, Matthew R.
AU - Casewell, Sarah L.
AU - Jenkins, James S.
AU - Raynard, Liam
AU - Smith, Alexis M. S.
AU - Tilbrook, Rosanna H.
AU - Vines, Jose I.
PY - 2020/1/8
Y1 - 2020/1/8
N2 - We determine rotation periods for 127 stars in the ~115 Myr old Blanco 1
open cluster using ~200 days of photometric monitoring with the Next
Generation Transit Survey (NGTS). These stars span F5-M3 spectral types
(1.2 $\gtrsim M \gtrsim$ 0.3 M$_{\odot}$) and increase the number of
known rotation periods in Blanco 1 by a factor of four. We determine
rotation periods using three methods: Gaussian process (GP) regression,
generalised autocorrelation (G-ACF) and Lomb-Scargle (LS) periodograms,
and find that GPs and G-ACF are more applicable to evolving spot
modulation patterns. Between mid-F and mid-K spectral types, single
stars follow a well-defined rotation sequence from ~2 to 10 days,
whereas stars in photometric multiple systems typically rotate faster.
This may suggest that the presence of a moderate-to-high mass ratio
companion inhibits angular momentum loss mechanisms during the early
pre-main sequence, and this signature has not been erased at ~100 Myr.
The majority of mid-F to mid-K stars display evolving modulation
patterns, whereas most M stars show stable modulation signals. This
morphological change coincides with the shift from a well-defined
rotation sequence (mid-F to mid-K stars) to a broad rotation period
distribution (late-K and M stars). Finally, we compare our rotation
results for Blanco 1 to the similarly-aged Pleiades: the single star
populations in both clusters possess consistent rotation period
distributions, which suggests that the angular momentum evolution of
stars follows a well-defined pathway that is, at least for mid-F to
mid-K stars, strongly imprinted by ~100 Myr.
AB - We determine rotation periods for 127 stars in the ~115 Myr old Blanco 1
open cluster using ~200 days of photometric monitoring with the Next
Generation Transit Survey (NGTS). These stars span F5-M3 spectral types
(1.2 $\gtrsim M \gtrsim$ 0.3 M$_{\odot}$) and increase the number of
known rotation periods in Blanco 1 by a factor of four. We determine
rotation periods using three methods: Gaussian process (GP) regression,
generalised autocorrelation (G-ACF) and Lomb-Scargle (LS) periodograms,
and find that GPs and G-ACF are more applicable to evolving spot
modulation patterns. Between mid-F and mid-K spectral types, single
stars follow a well-defined rotation sequence from ~2 to 10 days,
whereas stars in photometric multiple systems typically rotate faster.
This may suggest that the presence of a moderate-to-high mass ratio
companion inhibits angular momentum loss mechanisms during the early
pre-main sequence, and this signature has not been erased at ~100 Myr.
The majority of mid-F to mid-K stars display evolving modulation
patterns, whereas most M stars show stable modulation signals. This
morphological change coincides with the shift from a well-defined
rotation sequence (mid-F to mid-K stars) to a broad rotation period
distribution (late-K and M stars). Finally, we compare our rotation
results for Blanco 1 to the similarly-aged Pleiades: the single star
populations in both clusters possess consistent rotation period
distributions, which suggests that the angular momentum evolution of
stars follows a well-defined pathway that is, at least for mid-F to
mid-K stars, strongly imprinted by ~100 Myr.
KW - Astrophysics - Solar and Stellar Astrophysics
U2 - 10.1093/mnras/stz3251
DO - 10.1093/mnras/stz3251
M3 - Article
VL - 492
SP - 1008
EP - 1024
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
SN - 0035-8711
IS - 1
ER -