J/ApJ/904/140 Ruprecht 147 members & rot. data for 5 other cl. (Curtis+, 2020)
When do stalled stars resume spinning down? Advancing gyrochronology with
Ruprecht 147.
Curtis J.L., Agueros M.A., Matt S.P., Covey K.R., Douglas S.T., Angus R.,
Saar S.H., Cody A.M., Vanderburg A., Law N.M., Kraus A.L., Latham D.W.,
Baranec C., Riddle R., Ziegler C., Lund M.N., Torres G., Meibom S.,
Aguirre V.S., Wright J.T.
<Astrophys. J., 904, 140 (2020)>
=2020ApJ...904..140C 2020ApJ...904..140C
ADC_Keywords: Clusters, open; Stars, ages; Radial velocities; Proper motions;
Photometry, UBVRI; Spectral types; Effective temperatures;
Stars, masses; Cross identifications
Keywords: Open star clusters ; Stellar evolution ; Stellar ages ;
Stellar rotation
Abstract:
Recent measurements of rotation periods (Prot) in the benchmark open
clusters Praesepe (670Myr), NGC6811 (1Gyr), and NGC752 (1.4Gyr)
demonstrate that, after converging onto a tight sequence of slowly
rotating stars in mass-period space, stars temporarily stop spinning
down. These data also show that the duration of this epoch of stalled
spin-down increases toward lower masses. To determine when stalled
stars resume spinning down, we use data from the K2 mission and the
Palomar Transient Factory to measure Prot for 58 dwarf members of
the 2.7Gyr old cluster Ruprecht 147, 39 of which satisfy our criteria
designed to remove short-period or near-equal-mass binaries. Combined
with the Kepler Prot data for the approximately coeval cluster
NGC6819 (30 stars with M*>0.85M☉), our new measurements more
than double the number of ∼2.5Gyr benchmark rotators and extend this
sample down to ∼0.55M☉. The slowly rotating sequence for this
joint sample appears relatively flat (22±2days) compared to
sequences for younger clusters. This sequence also intersects the
Kepler intermediate-period gap, demonstrating that this gap was not
created by a lull in star formation. We calculate the time at which
stars resume spinning down and find that 0.55M☉ stars remain
stalled for at least 1.3Gyr. To accurately age-date low-mass stars in
the field, gyrochronology formulae must be modified to account for
this stalling timescale. Empirically tuning a core-envelope coupling
model with open cluster data can account for most of the apparent
stalling effect. However, alternative explanations, e.g., a temporary
reduction in the magnetic braking torque, cannot yet be ruled out.
Description:
We have observed 130 cluster stars with Robo-AO in 2013 while it was
on the Palomar 60-inch telescope (see Curtis 2016PhDT.......246C 2016PhDT.......246C), of
which 50 are dwarfs less massive than the 1.4M☉ cutoff for this
study. See Section 2.3.3.
Our team petitioned to adjust the pointing for K2's Campaign 7 so that
it covered Ruprecht 147, which we then proposed to monitor
(GO proposal 7035). Our GO program was allocated 1086 individual
apertures for candidate members. A series of contiguous apertures, a
"superstamp", was created to tile the inner cluster core in response
to a different proposal and covered 96 additional candidates from our
preliminary membership list (Cody+ 2018RNAAS...2Q..25C 2018RNAAS...2Q..25C).
See Section 3.1.
We monitored Ruprecht 147 from 2012 April 29 to 2012 October 7 as part
of the PTF Open Cluster Survey. This survey used the robotic 48-inch
Oschin (P48) telescope at Palomar Observatory, CA. See Section 3.2.
Objects:
----------------------------------------------------------
RA (ICRS) DE Designation(s)
----------------------------------------------------------
19 16 21 -16 20.0 Cl Ruprecht 147 = NGC 677
08 40 13 +19 37.3 NAME Praesepe = NGC 2632
03 46 24 +24 06.8 NAME Pleiades = Cl Melotte 22
19 37 22 +46 22.7 NGC 6811 = NGC 6811
19 41 18 +40 11.4 NGC 6819 = NGC 6819
01 56 54 +37 47.6 NGC 752 = NGC 752
----------------------------------------------------------
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 873 440 Ruprecht 147 catalog
table5.dat 144 923 Data for the Pleiades, Praesepe, NGC 6811, NGC 752,
NGC 6819, and Ruprecht 147 clusters
--------------------------------------------------------------------------------
See also:
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
I/289 : UCAC2 Catalogue (Zacharias+ 2004)
I/297 : NOMAD Catalog (Zacharias+ 2005)
I/317 : The PPMXL Catalog (Roeser+ 2010)
IV/34 : K2 Ecliptic Plane Input Catalog (EPIC) (Huber+, 2017)
I/347 : Distances to 1.33 billion stars in Gaia DR2 (Bailer-Jones+, 2018)
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
V/154 : Sloan Digital Sky Surveys (SDSS), Release 16 (DR16) (Ahumada+, 2020)
J/A+A/619/A73 : Solar Twins age-chromospheric act. (Lorenzo-Oliveira+, 2018)
J/A+A/417/557 : Rotation & variability of PMS Stars in NGC 2264 (Lamm, 2004)
J/ApJS/152/261 : Chromospheric Ca II emission in nearby stars (Wright+, 2004)
J/AJ/130/1916 : Metallicity indices in open clusters (Marshall+, 2005)
J/ApJS/159/141 : Spectroscopic properties of cool stars. I. (Valenti+, 2005)
J/AJ/134/2340 : Membership of Praesepe & Coma Berenices (Kraus+, 2007)
J/AJ/135/2264 : Stellar radial velocities in NGC 188 (Geller+, 2008)
J/ApJ/687/1264 : Age estimation for solar-type dwarfs (Mamajek+, 2008)
J/ApJ/691/342 : griBVI photometry in M37 (Hartman+, 2009)
J/AJ/138/159 : NGC 6819 stellar radial-velocity and photometry (Hole+, 2009)
J/AJ/137/5086 : NGC 188 V12 VI light curves (Meibom+, 2009)
J/ApJ/695/679 : Stellar rotation in M35 (Meibom+, 2009)
J/ApJS/190/1 : A survey of stellar families (Raghavan+, 2010)
J/ApJ/733/L9 : Stellar rotation for 71 NGC 6811 members (Meibom+, 2011)
J/ApJ/733/115 : Rotation periods and membership in M34 (Meibom+, 2011)
J/ApJ/757/112 : Stellar diameters. II. K and M-stars (Boyajian+, 2012)
J/AJ/145/134 : Radial velocities of 108 stars in Ruprecht 147 (Curtis+, 2013)
J/MNRAS/432/1203 : Rotation periods of M-dwarf stars (McQuillan+, 2013)
J/AJ/146/43 : WIYN open cluster study. LV. NGC 6819 (Platais+, 2013)
J/A+A/552/A64 : Gaia-RVS standards (Soubiran+, 2013)
J/ApJ/776/67 : Rotational tracks (van Saders+, 2013)
J/AJ/148/51 : WIYN Open Cluster. LXI. NGC6819 photo. (Anthony-Twarog+, 2014)
J/ApJS/211/24 : Rotation periods of Kepler MS stars (McQuillan+, 2014)
J/AJ/148/38 : WIYN open cluster study. LX. NGC6819 RVs (Milliman+, 2014)
J/ApJS/215/19 : APOKASC catalog of Kepler red giants (Pinsonneault+, 2014)
J/A+A/583/A73 : Color-period diagram for M48 (NGC2548) (Barnes+, 2015)
J/AJ/149/121 : WOCS. LXV. Abundances in NGC 6819 (Lee-Brown+, 2015)
J/ApJ/804/64 : Empirical and model parameters of 183 M dwarfs (Mann+, 2015)
J/AJ/150/134 : uvbyCaHβ photometry of NGC 752 (Twarog+, 2015)
J/MNRAS/448/822 : LAMOST candidate members of star clusters (Xiang+, 2015)
J/ApJS/225/32 : Extended abundance analysis of cool stars (Brewer+, 2016)
J/AJ/151/66 : Velocities of WOCS24009 & WOCS40007 in NGC6819 (Brewer+, 2016)
J/ApJ/822/81 : PTF stellar rotation periods Pleiades members (Covey+, 2016)
J/ApJ/822/47 : K2 rotation periods for 65 Hyades members (Douglas+, 2016)
J/ApJS/224/2 : K2 EPIC stellar properties for 138600 targets (Huber+, 2016)
J/MNRAS/463/696 : M67 solar twins chemical compositions (Liu+, 2016)
J/ApJ/823/114 : The Cannon: a new approach to determine masses (Ness+, 2016)
J/AJ/152/113 : Pleiades members with K2 LCs. I. Periods (Rebull+, 2016)
J/AJ/152/115 : Pleiades members with K2 light curves. III. (Stauffer+, 2016)
J/ApJ/842/83 : Praesepe members rotational periods K2 LCs (Douglas+, 2017)
J/ApJ/835/75 : Common proper motion stars in the Kepler field (Janes, 2017)
J/ApJ/845/72 : Factory & the beehive. III. PTFEB132.707+19.810 (Kraus+, 2017)
J/AJ/154/107 : California-Kepler Survey (CKS). I. (Petigura+, 2017)
J/ApJ/839/92 : Praesepe members with K2 light curve data (Rebull+, 2017)
J/ApJ/862/33 : Improved & expanded membership catalog NGC752 (Agueros+, 2018)
J/AJ/155/138 : WOCS.LXXVI. Vel. & abund. of NGC2506 (Anthony-Twarog+,2018)
J/A+A/619/A176 : Chemical composition of Ruprecht 147 (Bragaglia+, 2018)
J/ApJS/237/38 : Extended abundance analysis of KOIs (Brewer+, 2018)
J/A+A/618/A93 : Gaia DR2 open clusters in the Milky Way (Cantat-Gaudin+, 2018)
J/AJ/155/173 : K2 light curve for K2-231 (Curtis+, 2018)
J/AJ/156/142 : Precision cluster abund. APOGEE using SDSS DR14 (Donor+, 2018)
J/A+A/616/A10 : 46 open clusters GaiaDR2 HR diag. (Gaia Collaboration, 2018)
J/AJ/155/196 : Analysis of K2 LCs members of USco & ρ Oph (Rebull+, 2018)
J/AJ/156/83 : Stellar companions effects in planetary syst. (Ziegler+, 2018)
J/ApJ/879/49 : Rotation periods for 171 Gaia members NGC6811 (Curtis+, 2019)
J/AJ/158/77 : Candidates & members of Pisces-Eridanus stream (Curtis+, 2019)
J/AJ/158/163 : Li abundance values for stars in NGC 6819 (Deliyannis+, 2019)
J/ApJ/879/100 : K2 Prot for Hyades & Praesepe members (Douglas+, 2019)
J/AJ/158/122 : Local structure & SFH of the MW (Kounkel+, 2019)
J/A+A/625/A115 : Ruprecht 147 DANCe. I. (Olivares+, 2019)
J/A+A/621/A21 : Activity of Kepler stars (Reinhold+, 2019)
J/ApJ/887/109 : EBs in Ruprecht 147. II. EPIC219568666 RVs (Torres+, 2019)
J/AJ/160/90 : Stellar parameters for 13196 Kepler dwarfs (Angus+, 2020)
J/A+A/635/A8 : Differential abundances of open clusters (Casamiquela+, 2020)
J/AJ/159/199 : OCCAM. IV. Open cluster abund using APOGEE DR16 (Donor+, 2020)
J/A+A/635/A43 : Stellar rotation periods K2 Campaigns 0-18 (Reinhold+, 2020)
J/ApJ/896/162 : EBs in Ruprecht 147. III. EPIC 219552514 (Torres+, 2020)
J/A+A/636/A74 : HARPS radial velocity database (Trifonov+, 2020)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 A8 --- --- [Gaia DR2]
10- 28 I19 --- GaiaDR2 ? Gaia DR2 Source ID
30- 34 A5 --- --- [2MASS]
36- 52 A17 --- 2MASS 2MASS Source ID (JHHMMSSss+DDMMSSs)
54- 57 A4 --- --- [EPIC ]
59- 67 I9 --- EPIC [216809289/229228368]? K2 EPIC ID
69- 71 A3 --- --- [CWW ]
73- 75 I3 --- CWW [1/108]? Identifier from
Curtis+, 2013, J/AJ/145/134
(<[CWW2013] NNN> in Simbad)
77- 79 A3 --- --- [NID]
81- 92 A12 --- NOMAD1 NOMAD identifier
(Zacharias+, 2005, I/297)
94- 102 F9.5 deg RAdeg [283.2/294] Right Ascension (ICRS)
at Epoch=2015.5
104- 113 F10.6 deg DEdeg [-21.7/-10.7] Declination (ICRS)
at Epoch=2015.5
115- 126 F12.9 mas/yr pmRA [-6.1/4.8] Right ascension proper motion
128- 137 F10.6 mas/yr pmDE [-34.9/-21.5] Declination proper motion
139- 147 F9.7 mas/yr e_pmRA [0/4.8]? Proper motion error
149- 156 A8 --- Source Source of astrometry (1)
158- 167 F10.7 mas plx [-6.3/10.6]? Parallax
169- 177 F9.7 mas e_plx [0.02/2.4]? Uncertainty in Parallax
179- 188 F10.8 --- epsi [0/6.4]? Astrometric excess noise
190- 202 E13.10 --- sepsi [0/11200]? Significance of astrometric
excess noise
204- 213 F10.6 --- ruwe [-1/79.5]? Re-normalised Unit-Weight Error
215- 223 F9.5 mag Gmag [6.4/20.8]? Gaia DR2 G band magnitude
225- 236 F12.8 mag BP-RP [-0.17/3.16]? Gaia DR2 color: (GBP-GRP)
238- 248 F11.9 mag e_BP-RP [0.0007/0.8]? Gaia DR2 Photometric error (2)
250- 258 F9.5 mag Jmag [4.3/17]? 2MASS J magnitude
260- 268 F9.5 mag Kmag [3.3/17.1]? 2MASS Ks magnitude
270- 278 F9.7 mag eJ-K [0.02/0.7]? 2MASS J-Ks color error (2)
280- 287 F8.4 km/s RVGaia [-65/71]? Gaia DR2 radial velocity
289- 297 F9.6 km/s e_RVGaia [0.1/13.2]? Gaia DR2 radial velocity error
299- 306 F8.4 km/s RV [-42/102]? Median radial velocity from
non-Gaia data (RV_R147Project)
308- 316 F9.5 --- o_RV [0/41] Number of non-Gaia RV measurements
318- 328 F11.7 --- eRV [0.019/375]? RV variability to error ratio
(3)
330- 341 F12.7 km/s dRV [-107/60]? RV deviation from cluster
343- 355 F13.8 d delTrv [0/4346]? RV epoch baseline
357- 404 A48 --- Member Membership ("Yes"=395 occurrences) (4)
406- 408 A3 --- pBin Photometric binary from CMD (5)
410- 412 A3 --- WBin Wide Binary? (6)
414- 422 A9 --- SpBin Spectroscopic Binary? (7)
424- 434 F11.9 deg rad [0.035/6.03] Radial RA/Dec coordinate
distance
436- 447 F12.8 pc drad [0.17/531]? 3D distance from cluster center
449 A1 --- f_drad I=Infinity
451- 461 F11.9 mas/yr pmd [0.06/9.7] Proper motion deviation from
cluster
463- 475 F13.9 mas dplx [-9.5/7.3]? Parallax deviation from cluster
477- 487 E11.8 mag dcmd [-1.98/0.95]? Photometric excess in G
489- 491 A3 --- AO Robo-AO detection, Yes, No, N/A
493- 501 F9.5 mag nmag [12.6/15.8]?=0 G band magnitude of brightest
neighbor within 12"
503- 511 F9.5 arcsec nrad [8.1/14.6]?=0 Distance to brightest neighbor
within 12"
513- 522 F10.4 K Teff [3152/10607]? Effective temperature
524- 533 F10.8 Msun Mass [0.14/1.6]? Mass
535- 536 A2 --- SpT Spectral type
538- 540 A3 --- K2/PTF Observed by K2? PTF? (8)
542- 551 F10.6 d Prot [-21/30]? Rotation period
553- 556 A4 --- r_Prot Source of Prot light curve (9)
558- 567 F10.6 10-3 sigmaLC [0/245]? Photometric noise for light curve,
parts per thousand
569- 578 F10.6 10-3 RvarLC [0/245] Photometric amplitude for light
curve, parts per thousand
580- 598 A19 --- Bench Benchmark (10)
600- 873 A274 --- Notes Notes (11)
--------------------------------------------------------------------------------
Note (1): Source of positions and proper motions as follows:
GaiaDR2 = Gaia DR2 (2018, I/345 ; 437 occurrences)
PPMXL = Cat. of Positions and Proper Motions eXtended-L (2010, I/317 ;
2 occurrences),
Oli-pm = Olivares+ 2019, J/A+A/625/A115 (1 occurrence)
Note (2): Color error is the quadratic uncertainty from the individual
magnitude uncertainties
Note (3): RV variability to error ratio (e/i; Geller+ 2008, J/AJ/135/2264)
Note (4): Reason for possible or non-members:
No: RV non-member = 9 occurrences
No: UVW>10_kms & d>100_pc = 4 occurrences
No: d>100_pc = 30 occurrences
Possible SB1: 5<UVW<10_kms & d>100_pc = 1 occurrence
Possible evaporated SB1: 5<UVW<10_kms & d>100_pc = 1 occurrence
Note (5): Photometric binary status set if |dcmd|>0.4mag then "Yes", else "No"
Note (6): Wide binary status is "Yes" if (pmd>2 mas/yr) or (AO=Yes)
or (RUWE>1.4), else "No"
Note (7): Spectroscopic binary status as follows:
SB2 = 23 occurrences
SB1-Short = 30 occurrences
SB1-Long = 5 occurrences
No = 110 occurrences
N/A = 262 occurrences
RV-NM = RV non-member (9 occurrences)
UVW-NM = UVW non-member (1 occurrence)
Note (8): Observed by K2? (S=superstamp, A=aperture, N=No) or the Palomar
Transient Factory (PTF)? (Y/N)
Note (9): Light curve used to measure Prot: PTF (4 occurrences),
K2 (148 occurrences), or both (3 occurrences).
Note (10): No/Yes/Yes-Rapid Outlier/Yes-Prot Secondary?
To reproduce our benchmark rotator sample, query "Prot">0 and
"Benchmark"="Yes"
Note (11): Notes on K2 light curve or the target
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table5.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 12 A12 --- Cluster Cluster Name (Pleiades, Praesepe, NGC 6811,
NGC 752, NGC 6819 or Ruprecht 147)
14- 18 F5.3 Gyr Age [0.12/2.7] Cluster Age
20- 24 F5.3 mag Av [0.035/0.44] Average cluster reddening
26- 33 A8 --- --- [Gaia DR2]
35- 53 I19 --- GaiaDR2 Gaia DR2 Source ID
55- 68 A14 --- OName Other name -- EPIC or KIC identifier (1)
70- 79 F10.6 deg RAdeg [28.69/295.74] Source Right Ascension,
(ICRS) at Epoch=2015.5
81- 90 F10.6 deg DEdeg [-17.9/47] Source Declination (ICRS)
at Epoch=2015.5
92- 99 F8.6 mag BP-RP [0.5/3.5] Gaia DR2 color: (GBP-GRP)
101-108 F8.6 mag (BP-RP)0 [0.4/3.4] Dereddened BP-RP color (2)
110-117 F8.5 mag Gmag [8.5/19.5] Gaia DR2 G band magnitude
119-126 F8.5 mag GMag [2.69/13.05] Absolute G band magnitude (2)
128-134 F7.2 K Teff [2933/7034] Effective temperature (3)
136-144 F9.6 d Prot [0.17/34.2] Rotational period
--------------------------------------------------------------------------------
Note (1): This column provides KIC or EPIC identification numbers where
available; NGC 752 was not observed by Kepler/K2, so the field is empty
for its stars.
Note (2): (BP-RP)0 and GMag were calculated using parallaxes from Gaia DR2
and the listed AV values together with the following approximate
relations: E(BP-RP)=0.415AV, and AG=0.86AV.
Note (3): Based on our empirical color-temperature relation.
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS], 25-Mar-2022