J/ApJ/938/118 CFHT monitoring of M67 & members from Gaia EDR3 (Dungee+, 2022)
A 4Gyr M-dwarf gyrochrone from CFHT/MegaPrime monitoring of the open cluster
M67.
Dungee R., van Saders J., Gaidos E., Chun M., Garcia R.A., Magnier E.A.,
Mathur S., Santos A.R.G.
<Astrophys. J., 938, 118 (2022)>
=2022ApJ...938..118D 2022ApJ...938..118D
ADC_Keywords: Clusters, open; Photometry, ugriz; Proper motions;
Parallaxes, trigonometric; Stars, K-type; Stars, M-type
Keywords: Open star clusters ; Stellar evolution ; Stellar ages ;
Stellar rotation
Abstract:
We present stellar rotation periods for late K- and early M-dwarf
members of the 4Gyr old open cluster M67 as calibrators for
gyrochronology and tests of stellar spin-down models. Using Gaia EDR3
astrometry for cluster membership and Pan-STARRS (PS1) photometry for
binary identification, we build this set of rotation periods from a
campaign of monitoring M67 with the Canada-France-Hawaii Telescope's
MegaPrime wide-field imager. We identify 1807 members of M67, of which
294 are candidate single members with significant rotation period
detections. Moreover, we fit a polynomial to the period versus color-
derived effective temperature sequence observed in our data. We find
that the rotation of very cool dwarfs can be explained by simple
solid-body spin-down between 2.7 and 4Gyr. We compare this rotational
sequence to the predictions of gyrochronological models and find that
the best match is Skumanich-like spin-down, Prot∝t0.62,
applied to the sequence of Ruprecht 147. This suggests that, for
spectral types K7-M0 with near-solar metallicity, once a star resumes
spinning down, a simple Skumanich-like relation is sufficient to
describe their rotation evolution, at least through the age of M67.
Additionally, for stars in the range M1-M3, our data show that
spin-down must have resumed prior to the age of M67, in conflict with
the predictions of the latest spin-down models.
Description:
Our campaign used CFHT's MegaPrime to monitor M67 (center coordinates:
RAJ2000=08:51:18,DEJ2000=+11:48:00) from 2018-Oct-15 to 2021-Mar-05 (UT).
In total we obtained 694 exposures of the cluster in discrete runs of
1-2 weeks, producing 131 epochs of data for our light curves. All data
were collected with 121s integration times using the Sloan i filter.
Objects:
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RA (ICRS) DE Designation(s)
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08 51 23.04 +11 48 50.4 M67 = NGC 2682
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 150 45 *Parameters for M dwarfs used for (r-i)-Teff relation
table2.dat 313 1807 Catalog of M67 members
table3.dat 101 383 *Detected Lomb-Scargle failure modes (see Section 5.1)
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Note on table1.dat: All values here are pulled from Mann+ 2015, J/ApJ/804/64,
this is the subset used for creating our relation used to calculate
Teffs from PS1 (r-i) colors, the synthetic PS1 photometry is
calculated using the Sloan to PS1 relations in Tonry+ 2012, J/ApJ/750/99
Note on table3.dat: The lomb-scargle failure modes are computed using
equation 47 of VanderPlas (2008ApJS..236...16V 2008ApJS..236...16V):
Pobs=|(m/Ptrue)+(n/δP)|-1 (Equation (9))
where Pobs is the observed peak in the periodogram, Ptrue is the
true period of the underlying signal, and m and n are integers.
Parameters m=1 and n=0 yield the true period, and m=2 and n=0
represent the classic case of half-period aliasing; however, they can
both take any integer value, positive or negative. The final term,
δP, is the period of a peak in the window function's periodogram
All alias and failure mode values are the output of Equation (9) with
Ptrue=Prot and are only included in the table if a peak was
detected at that period in the periodogram.
The δf value in that equation is computed from peak in window
function of observations, for this table we have included results
using peak at ∼29.5 days and ∼380.8 days, precise value varies
slightly with each target due to variations in exactly how it is
sampled in time.
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See also:
I/350 : Gaia EDR3 (Gaia Collaboration, 2020)
IV/39 : TESS Input Catalog version 8.2 (TIC v8.2) (Paegert+, 2021)
I/355 : Gaia DR3 Part 1. Main source (Gaia Collaboration, 2022)
J/AJ/106/181 : CCD photometry of open cluster M67 (Montgomery+ 1993)
J/AJ/112/628 : BATC Color Survey of M67 (Fan+ 1996)
J/A+A/470/585 : NGC 2682 uvby-Hbeta photometry (Balaguer-Nunez+, 2007)
J/ApJ/687/1264 : Age estimation for solar-type dwarfs (Mamajek+, 2008)
J/A+A/489/403 : Line abundances for solar stars (Pace+, 2008)
J/ApJ/695/679 : Stellar rotation in M35 (Meibom+, 2009)
J/ApJ/743/48 : Stars with rot. periods & X-ray luminosities (Wright+, 2011)
J/ApJ/750/99 : The Pan-STARRS1 photometric system (Tonry+, 2012)
J/MNRAS/432/1203 : Rotation periods of M-dwarf stars (McQuillan+, 2013)
J/ApJ/776/67 : Rotational tracks (van Saders+, 2013)
J/ApJ/780/159 : Rot-mass-age relations of old field stars (Epstein+, 2014)
J/ApJ/807/45 : Habitable planets around M dwarfs (Dressing+, 2015)
J/ApJ/804/64 : Empirical and model parameters of 183 M dwarfs (Mann+, 2015)
J/ApJ/833/281 : Candidate rotating M dwarfs from PS1-MDS (Kado-Fong+, 2016)
J/MNRAS/463/696 : M67 solar twins chemical compositions (Liu+, 2016)
J/ApJ/821/93 : Rot & Galactic kinematics of mid M dwarfs (Newton+, 2016)
J/AJ/152/113 : Pleiades members with K2 LCs. I. Periods (Rebull+, 2016)
J/ApJ/842/83 : Praesepe members rot. periods from K2 LCs (Douglas+, 2017)
J/ApJ/834/85 : Hα emission in nearby M dwarfs (Newton+, 2017)
J/ApJ/839/92 : Praesepe members with K2 light curve data (Rebull+, 2017)
J/ApJ/862/33 : Improved & expanded membership for NGC752 (Agueros+, 2018)
J/ApJ/869/9 : Machine-learning investigation of M67 (Gao, 2018)
J/AJ/156/217 : Stellar data for M dwarfs in MEarth-South (Newton+, 2018)
J/ApJ/879/49 : Rot. periods for Gaia members of NGC 6811 (Curtis+, 2019)
J/A+A/621/A126 : CARMENES input catalog of M dwarfs. IV. (Diez Alonso+ 2019)
J/ApJ/879/100 : K2 rot. per. for Hyades & Praesepe members (Douglas+, 2019)
J/AJ/158/75 : M dwarfs planet occurrence rates (Hardegree-Ullman+, 2019)
J/A+A/621/A21 : Activity of Kepler stars (Reinhold+, 2019)
J/ApJS/244/21 : Surface rot. & activity of Kepler stars. I. (Santos+, 2019)
J/AJ/157/216 : Stellar mult. rate of M dwarfs within 25pc (Winters+, 2019)
J/ApJ/904/140 : R147 members & rot. data for 5 other cl. (Curtis+, 2020)
J/ApJ/895/140 : EvryFlare. II. Param. of cool flare stars (Howard+, 2020)
J/ApJ/898/76 : Rot. vel. of APOGEE stars in Kepler field (Simonian+, 2020)
J/AJ/161/189 : Gyro-kinematic ages for ∼30000 Kepler stars (Lu+, 2021)
J/ApJ/916/77 : K2 rot. periods for SDSS & Gaia M dwarfs (Popinchalk+, 2021)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 15 A15 --- Name Source Name used in Mann+ 2015, J/ApJ/804/64
17- 26 F10.6 deg RAdeg Right Ascension in decimal degrees (J2000)
28- 37 F10.6 deg DEdeg Declination in decimal degrees (J2000)
39- 44 F6.3 mag Gmag [7/13.6] Synthetic Gaia G magnitude
46- 51 F6.3 mag BPmag [0/16.2] Synthetic Gaia BP magnitude
53- 58 F6.3 mag RPmag [0/12.2] Synthetic Gaia RP magnitude
60- 64 F5.3 Msun M0 [0.1/0.7] Stellar mass
66- 70 F5.3 Msun e_M0 [0.004/0.02] Uncertainty in M0
72- 76 F5.2 [Sun] [Fe/H] [-0.06/0.06] Metallicity
78- 81 F4.2 [Sun] e_[Fe/H] [0.03/0.08] Uncertainty in Metallicity
83- 86 I4 K Teff [2829/4013] Effective temperature
88- 93 F6.3 mag gmag [8.41/16.74] Synthetic PS1 g magnitude
95- 99 F5.3 mag e_gmag [0.02/0.03] Uncertainty in gmag
101- 106 F6.3 mag rmag [7.06/15.08] Synthetic PS1 r magnitude
108- 112 F5.3 mag e_rmag [0.01/0.02] Uncertainty in rmag
114- 119 F6.3 mag imag [6.46/12.82] Synthetic PS1 i magnitude
121- 125 F5.3 mag e_imag [0.01/0.02] Uncertainty in imag
127- 132 F6.3 mag zmag [6.13/11.56] Synthetic PS1 z magnitude
134- 138 F5.3 mag e_zmag [0.01/0.02] Uncertainty in zmag
140- 144 F5.3 mag Ksmag [4/9] Synthetic Ks magnitude
146- 150 F5.3 mag e_Ksmag [0.019/0.02] Uncertainty in Ksmag
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 18 I18 --- Gaia Source ID in Gaia EDR3 (gaiaid)
20- 33 F14.10 deg RAdeg [132.1/133.6] Right Ascension (ICRS)
at Ep=2016
35- 39 F5.3 mas e_RAdeg [0.01/1.1] Uncertainty in RAdeg
41- 53 F13.10 deg DEdeg [11.1/12.5] Declination (ICRS) at Ep=2016
55- 60 F6.4 mas e_DEdeg [0.005/0.6] Uncertainty in DEdeg
62- 67 F6.3 mas plx [-0.4/2.7] Parallax in Gaia EDR3
69- 73 F5.3 mas e_plx [0.013/1.4] Uncertainty in plx
75- 81 F7.3 mas/yr pmRA [-12.9/-8.6] Gaia EDR3 proper motion in RA
83- 87 F5.3 mas/yr e_pmRA [0.013/1.7] Uncertainty in pmRA
89- 94 F6.3 mas/yr pmDE [-4.7/-0.7] Gaia EDR3 proper motion in Dec
96- 100 F5.3 mas/yr e_pmDE [0.01/1.3] Uncertainty in pmDE
102- 108 F7.4 --- ruwe [0.76/16] Gaia EDR3 renormalized unit weight
error
110- 116 F7.4 mag Gmag [7.94/20.71]? Gaia EDR3 G magnitude
118- 123 F6.4 mag e_Gmag [0.002/0.01]? Uncertainty in Gmag
125- 131 F7.4 mag BPmag [9.05/21.84]? Gaia EDR3 BP magnitude
133- 138 F6.4 mag e_BPmag [0.002/0.4]? Uncertainty in BPmag
140- 146 F7.4 mag RPmag [6.9/19.9]? Gaia EDR3 RP magnitude
148- 153 F6.4 mag e_RPmag [0.003/0.15]? Uncertainty in RPmag
155- 172 I18 --- objid ?=-1 PS1 DR2 objID (ps1id)
174- 184 F11.6 mag gmag [/22.4]?=-999 PS1 DR2 g magnitude
186- 193 F8.6 mag e_gmag [1.7e-05/0.32]? Uncertainty in gmag
195- 205 F11.6 mag rmag [/21.4]?=-999 PS1 DR2 r magnitude
207- 214 F8.6 mag e_rmag [1.9e-05/0.17]? Uncertainty in rmag
216- 226 F11.6 mag imag [/20.23]?=-999 PS1 DR2 i magnitude
228- 235 F8.6 mag e_imag [4.3e-05/0.32]? Uncertainty in imag
237- 247 F11.6 mag zmag [/20.52]?=-999 PS1 DR2 z magnitude
249- 256 F8.6 mag e_zmag [5.3e-05/0.22]? Uncertainty in zmag
258- 262 F5.3 --- PMm [0.5/1] M67 member probability based on
astrometry (memberprob)
264- 268 A5 --- Single Flagged as a single star
270- 274 A5 --- Bin Flagged as a multiple star system
276- 280 A5 --- G18Mm Is also a member of M67 in
Gao 2018, J/ApJ/869/9 (gaomember)
282- 286 A5 --- suspect Is potentially suspect as a member of M67
288- 292 A5 --- Fit Was used for the fit to sequence (converged)
294- 297 I4 K Teff [3202/4095]? Effective temperature computed
from PS1 r-i
299- 304 F6.2 d Prot [2.97/826.0]? Measured rotation period of star
306- 313 A8 --- Fap False Alarm Probability of rotation period
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 18 I18 --- Gaia The Gaia EDR3 source_id number of star
20- 25 F6.2 d Prot [2.97/826] The measured rotation period of
star
27- 34 A8 --- Fap False Alarm probability of rotation period
36- 41 F6.2 d HalfPer [2.9/413]? If present in periodogram,
lomb-scargle failure mode with m=2 & n=0
43- 48 F6.2 d 3dPer [2.79/275]? If present in periodogram,
lomb-scargle failure mode with m=3 & n=0
50- 54 F5.2 d Month1n-2 [3.69/47]? If present in periodogram,
lomb-scargle failure mode with m=1 & n=-2,
for ∼month peak in window function,
δP∼29.5days
56- 61 F6.2 d Month2n-1 [3.3/806]? If present in periodogram,
lomb-scargle failure mode with m=1 & n=-1,
for ∼month peak in window function,
δP∼29.5days
63- 67 F5.2 d Month3n+1 [2.89/28.7]? If present in periodogram,
lomb-scargle failure mode with m=1 & n=+1,
for ∼month peak in window function,
δP∼29.5days
69- 73 F5.2 d Month4n+2 [3/14.6]? If present in periodogram,
lomb-scargle failure mode with m=1 & n=+2,
for ∼month peak in window function,
δP∼29.5days
75- 80 F6.2 d Year1n-2 [2.99/806]? If present in periodogram,
lomb-scargle failure mode with m=1 & n=-2,
for ∼year peak in window function,
δP∼380.8days
82- 87 F6.2 d Year2n-1 [2.97/806]? If present in periodogram,
lomb-scargle failure mode with m=1 & n=-1,
for ∼year peak in window function,
δP∼380.8days
89- 94 F6.2 d Year3n+1 [2.97/242]? If present in periodogram,
lomb-scargle failure mode with m=1 & n=+1,
for ∼year peak in window function,
δP∼380.8days
96- 101 F6.2 d Year4n+2 [2.9/155]? If present in periodogram,
lomb-scargle failure mode with m=1 & n=+2,
for ∼year peak in window function,
δP∼380.8days
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 29-Aug-2024