J/AJ/165/105 Stromgren photometry in M67 (Twarog+, 2023)
A uvbyCaHβ CCD Analysis of the Open Cluster Standard, M67, and Its
Relation to NGC 752.
Twarog B.A., Anthony-Twarog B.J., Deliyannis C.P.
<Astron. J., 165, 105 (2023)>
=2023AJ....165..105T 2023AJ....165..105T
ADC_Keywords: Clusters, open; Photometry, H-beta; Colors
Keywords: Open star clusters ; Stromgren photometry
Abstract:
Precision CCD uvbyCaHβ photometry is presented of the old
cluster, M67, covering one square degree with typical internal
precision at the 0.005-0.020mag level to V∼17. The photometry is
calibrated using standards over a wide range in luminosity and
temperature from NGC752 and zeroed to the standard system via
published photoelectric observations. Relative to NGC752, differential
offsets in reddening and metallicity are derived using astrometric
members, supplemented by radial velocity information. From single star
members, offsets in the sense (M67-NGC752) are
δE(b-y)=-0.005±0.001(sem)mag from 327 F/G dwarfs and
δ[Fe/H]=0.062±0.006(sem)dex from the combined m1 and hk
indices of 249 F dwarfs, leading to E(b-y)=0.021±0.004(sem) and
[Fe/H]M67=+0.030±0.016(sem) assuming [Fe/H]Hyades=+0.12. With
probable binaries eliminated using c1, (b-y) indices, 83 members with
(π/σπ)>50 generate (m-M)0=8.220±0.005(sem) for NGC752
and an isochronal age of 1.45±0.05Gyr. Using the same parallax
restriction for 312 stars, M67 has (m-M)=9.77±0.02(sem), leading
to an age tied solely to the luminosity of the subgiant branch of
3.70±0.03Gyr. The turnoff color spread implies ±0.1Gyr, but
the turnoff morphology defines a younger age/higher mass for the
stars, consistent with recent binary analysis and broadband photometry
indicating possible missing physics in the isochrones. Anomalous stars
positioned blueward of the turnoff are discussed.
Description:
Intermediate and narrowband images of M67 were obtained using the
Wisconsin-Indiana-Yale-NOIRLab (WIYN) 0.9m telescope during four
observing runs between 2015 November and 2017 February. During each
run, frames also were obtained in multiple fields of NGC752, observed
as the primary source of standards for the extended Stromgren and
Hβ systems. For all runs the telescope was equipped with the
Half-Degree-Imager (HDI), a 4Kx4K chip with 0.43" pixels covering a
29x29' field. The seven filters were from the extended Stromgren set
acquired for specific use with the HDI.
Objects:
-------------------------------------------
RA (2000) DE Designation(s)
-------------------------------------------
08 51 23.04 +11 48 50.4 M67 = C 0847+120
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File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 76 84 Merged photoelectric secondary standards in M67
table2.dat 50 19 Internal photoelectric hk secondary standards in M67
table4.dat 118 3494 Stromgren photometry in M67
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See also:
II/47 : Scanner Abundance in late-type evolved stars (Spinrad+ 1969)
II/183 : UBVRI Photometric Standards (Landolt 1992)
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
J/PASP/106/281 : Photometry and radial velocities in NGC752 (Daniel+, 1994)
J/AJ/109/2828 : CaII H and K filter photometry II. (Twarog+ 1995)
J/A+A/339/423 : Velocities of red giants in NGC 752 (Mermilliod+ 1998)
J/AJ/119/2282 : Stromgren photometry of IC 4651 (Anthony-Twarog+, 2000)
J/MNRAS/347/101 : Precision colour-magnitude diagram of M67 (Sandquist, 2004)
J/A+A/470/585 : NGC 2682 uvby-Hbeta photometry (Balaguer-Nunez+, 2007)
J/A+A/485/303 : Radial velocities for 1309 stars & 166 OCl (Mermilliod+, 2008)
J/ApJS/176/262 : VRI photometry & theta values in open clusters (Taylor+, 2008)
J/A+A/505/117 : Abundances red giants 15 globular clusters (Carretta+, 2009)
J/A+A/498/949 : Velocities 1253 F-K dwarfs open clusters (Mermilliod+, 2009)
J/AJ/139/2034 : NGC 6253 stars equivalent widths (Anthony-Twarog+, 2010)
J/AJ/145/134 : Radial velocities of 108 stars in Ruprecht 147 (Curtis+, 2013)
J/AJ/150/97 : RVvel in M67. I. 1278 candidate members (Geller+, 2015)
J/MNRAS/450/4301 : Line list for red giants in open clusters (Reddy+, 2015)
J/AJ/150/134 : uvbyCaHβ photometry of NGC 752 (Twarog+, 2015)
J/A+A/585/A150 : On the metallicity of open clusters. III. (Netopil+, 2016)
J/AJ/153/128 : WOCS. LXXV. Hyades&Praesepe stellar Li data (Cummings+, 2017)
J/ApJ/862/33 : Improved & expanded membership catalog NGC752 (Agueros+, 2018)
J/AJ/156/37 : Photo. & Li abund. cool dwarfs in M35 (Anthony-Twarog+, 2018)
J/A+A/618/A93 : Gaia DR2 open clusters in the Milky Way (Cantat-Gaudin+, 2018)
J/AJ/158/163 : Li abundance values for stars in NGC 6819 (Deliyannis+, 2019)
J/ApJ/878/99 : Abundances dwarfs & giants in NGC752 with HIRES (Lum+, 2019)
J/AJ/158/82 : DS Andromedae radial velocity & photometry (Milone+, 2019)
J/MNRAS/491/544 : NGC752 abundances from IR spectra (Bocek Topcu+, 2020)
J/AJ/159/199 : OCCAM. IV. Open cluster abund. with APOGEE DR16 (Donor+, 2020)
J/AJ/159/246 : WIYN open cluster study. LXXX. Photometry NGC7142 (Sun+, 2020)
J/AJ/161/190 : Radial Velocities of binary population in M67 (Geller+, 2021)
J/MNRAS/503/236 : UVIT catalog & membership of 6 open clusters (Jadhav+, 2021)
J/A+A/650/A67 : Blue and yellow straggler stars in open clusters (Rain+, 2021)
J/AJ/163/195 : Open Cluster Chemical Abund. & Mapping Survey.V. (Ray+, 2022)
J/AJ/165/6 : BD+37410 & DSAnd light curve & RVel (Sandquist+, 2023)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 I4 --- WEBDA Identification, WEBDA
7- 15 F9.5 deg RAdeg [132/134] Right Ascension (J2000 at Epoch 2016)
18- 25 F8.5 deg DEdeg [11/12] Declination (J2000 at Epoch 2016)
27- 32 F6.3 mag b-y [-0.04/0.49]? The (b-y) color
34- 38 F5.3 mag e_b-y [0.001/0.02]? Uncertainty (sem) in b-y
40- 44 F5.3 mag m1 [0.12/0.25]? The m1 index
46- 50 F5.3 mag e_m1 [0.002/0.02]? Uncertainty (sem) in c1
52- 56 F5.3 mag c1 [0.28/1.11]? The c1 index
58- 62 F5.3 mag e_c1 [0.002/0.02]? Uncertainty (sem) in m1
64- 68 F5.3 mag Hb [2.6/2.92]? The Hβ index
70- 74 F5.3 mag e_Hb [0.001/0.02]? Uncertainty (sem) in Hb
76- 76 I1 --- Note [1/2]? Calibration Classification (1)
--------------------------------------------------------------------------------
Note (1): Flag as follows:
1 = Stars for which c1 values were not used in the calibration relations
(3 occurrences)
2 = Indications of variability dictate omission from all calibration
relations for this star (1 occurrence)
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 I4 --- WEBDA Identification, WEBDA
6- 14 F9.5 deg RAdeg [132/134] Right Ascension (J2000 at Epoch 2016)
16- 23 F8.5 deg DEdeg [11/13] Declination (J2000 at Epoch 2016)
25- 30 F6.3 mag b-y [-0.03/0.85] The (b-y) color
32- 36 F5.3 mag e_b-y [0/0.02] Uncertainty (std) in b-y
38- 42 F5.3 mag hk [0.14/1.63] The hk index
44- 48 F5.3 mag e_hk [0/0.03] Uncertainty (std) in hk
50- 50 I1 --- Num [1/8] Number of measurements
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table4.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 F9.5 deg RAdeg [132/134] Right Ascension (J2000 at Epoch 2016)
11- 18 F8.5 deg DEdeg [11/13] Declination (J2000 at Epoch 2016)
20- 25 F6.3 mag Vmag [8.75/20] The V band magnitude
27- 32 F6.3 mag b-y [-0.21/1.41] The (b-y) color
34- 39 F6.3 mag m1 [-0.86/0.9]? The m1 index
41- 46 F6.3 mag c1 [-0.89/1.31]? The c1 index
48- 53 F6.3 mag hk [-1.58/2.01]? The hk index
55- 59 F5.3 mag Hb [2.28/2.92]? The Hβ index
61- 65 F5.3 mag e_Vmag [0/0.2] Uncertainty (sem) in Vmag
67- 71 F5.3 mag e_b-y [0.001/0.2] Uncertainty (sem) in b-y
73- 77 F5.3 mag e_m1 [0.001/0.3]? Uncertainty (sem) in m1
79- 83 F5.3 mag e_c1 [0.001/0.4]? Uncertainty (sem) in c1
85- 89 F5.3 mag e_hk [0.001/0.3]? Uncertainty (sem) in hk
91- 95 F5.3 mag e_Hb [0.001/0.3]? Uncertainty (sem) in Hb
97- 98 I2 --- Ny [1/64] Number of y filter observations
100-101 I2 --- Nb [1/61] Number of b filter observations
103-104 I2 --- Nv [0/58] Number of v filter observations
106-107 I2 --- Nu [0/59] Number of u filter observations
109-110 I2 --- NCa [0/67] Number of Ca filter observations
112-113 I2 --- Nn [0/58] Number of Hβ narrow filter observations
115-116 I2 --- Nw [0/59] Number of Hβ wide filter observations
118-118 A1 --- Class Calibration Classification (1)
--------------------------------------------------------------------------------
Note (1): Classes as follows:
B = Blue dwarf (1360 occurrences)
D = Red dwarf (2028 occurrences)
G = Red giant (106 occurrences)
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History:
From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDS], 13-Jun-2023