J/A+A/672/A85 Galactic Cepheid luminosity scale (Cruz Reyes+, 2023)
A 0.9% Calibration of the Galactic Cepheid luminosity scale based on
Gaia DR3 data of open clusters and Cepheids.
Cruz Reyes M., Anderson R.I.
<Astron. Astrophys. 672, A85 (2023)>
=2023A&A...672A..85C 2023A&A...672A..85C (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, open ; Stars, variable ; Radial velocities ;
Parallaxes, trigonometric
Keywords: stars: distances - stars: variables: Cepheids -
open clusters and associations: general - distance scale -
astrometry - parallaxes
Abstract:
We have conducted a search for open clusters in the vicinity of
Galactic classical Cepheids based on high-quality astrometry from the
ESA mission Gaia's third data release (DR3) to improve the
calibration of the Leavitt law. Our approach requires no prior
knowledge of existing clusters, allowing us to both detect new host
clusters and cross-check previously reported associations. Our Gold
sample consists of 34 Cepheids residing in 28 open clusters, including
27 fundamental mode and 7 overtone Cepheids. Three new bona fide
cluster Cepheids are reported (V0378 Cen, ST Tau and GH Lup) and the
host cluster identifications for three others (VW Cru, IQ Nor, SX Vel)
is corrected. The fraction of Cepheids occurring in open clusters
within 2 kpc of the Sun is fCC,2kpc=0.092±0.009. Non-variable
cluster members allow us to determine cluster parallaxes to 7 as in
the range 12.5<G<17mag where recent studies found that parallax
corrections by Lindegren et al. (2021A&A...649A...4L 2021A&A...649A...4L) are accurate and
require no further offset corrections. Comparing MW cluster Cepheids
to Cepheids in the LMC, we confirm these independent results and the
adequacy of the L21 corrections for the cluster members in this range.
Combining cluster and field Cepheids, we calibrate the Galactic
Cepheid Leavitt law for a variety of individual optical and
near-infrared passbands, as well as using reddening-free Wesenheit
magnitudes based on Gaia and HST photometry, while solving for the
residual offset applicable to Cepheid parallaxes, ΔϖCep.
The most direct comparison of our results with the SH0ES distance
ladder yields excellent (0.3σ) agreement for both the absolute
magnitude of a 10d Solar metallicity Cepheid in the _IR HST Wesenheit
magnitudes, MWH=-5.915±0.017mag, and the residual parallax
offset, ϖCl=-13±5uas. Despite the use of a common set of
photometry, this is an important cross-check of the recent Hubble
constant measurement by Riess et al. based on independently determined
cluster membership and average parallaxes. Allowing the LL slope to
vary yields results consistent to within 1 and a slightly larger
residual parallax offsets ΔϖCep=-17±5uas. Using the
larger sample of 26 Gold cluster Cepheids and 225 MW Cepheids with
recent Gaia DR3 astrometry and photometry, we determine the absolute
magnitude of a 10d fundamental mode Cepheid in the optical Gaia
Wesenheit magnitude at the sample average iron abundance of
<[Fe=H]≥0.069, MWG=-6.051±0.020mag, and
ΔϖCep=-22±3uas. Correcting to Solar metallicity yields
MWG=-5.996±0.019mag and ΔϖCep=-19±3uas. These
results mark the currently most accurate absolute calibrations of the
Cepheid luminosity scale based purely on observations of MW Cepheids,
as well as the most precise determination of the residual Cepheid
parallax offset at a significance of 6-7σ.
Description:
We carried out a systematic search for MW cluster Cepheids using
Gaia EDR3 and DR3 data. The improved proper motion precision of EDR3
over DR2 allows us to obtain a more detailed and accurate view of
cluster membership for previously discussed cluster Cepheids. This
enabled the identification of three new bona fide cluster Cepheids
belonging to the Gold sample, namely ST Tau, V0378 Cen and GH Lup.
Additionally, we corrected the host cluster identification for three
Cepheids previously discussed in the literature, namely SX Vel, IQ Nor
and VW Cru. We find SV Vul to be a bona fide cluster Cepheid and not
an outlier of the Galactic LL, and we identify the long-period
Cepheids XZ Car and X Pup as likely cluster Cepheids.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 83 29 Radial Velocity information of clusters Cepheids
table2-4.dat 131 39 Parameters of the Cluster Cepheids of the Gold,
Silver and Bronze samples
table7.dat 77 256 Field cepheids used for the calibration of the
Leavitt Law in different photometric bands
table10.dat 87 35 Astrometry and photometry of cluster Cepheids
tablea1.dat 52 6839 Cluster members of the Gold, Silver and Bronze
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See also:
I/355 : Gaia DR3 Part 1. Main source (Gaia Collaboration, 2022)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 12 A12 --- Cluster Cluster name
14- 16 I3 --- NRV Cluster members with radial velocities
from Gaia DR3
18- 23 F6.2 km/s RVmed Median RV
25- 29 F5.2 km/s e_RVmed Standard error of the median
31- 39 A9 --- Cepheid Cepheid name
41- 46 F6.2 km/s vgamma Radial velocity of the Cepheid
48- 51 F4.2 km/s e_vgamma Uncertainty in the radial velocity of
the Cepheid
53- 61 A9 --- r_vgamma References used to calculate the radial
velocity of the Cepheid (1)
63- 68 F6.2 km/s deltaCl-Cep Radial velocity of the cluster minus radial
velocity of the Cepheid
70- 74 F5.2 km/s sigmatot Cluster and Cepheid uncertainty added in
quadrature
76- 83 F8.2 --- N-sigma Difference in standard deviations between
radial velocities of Cepheid and Cluster
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Note (1): References as follows:
a = Barnes et al. (1988ApJS...66...43B 1988ApJS...66...43B)
b = Bersier et al. (1994A&AS..108...25B 1994A&AS..108...25B, Cat. J/A+AS/108/25)
c = Gorynya et al. (1992PAZh...18..777G 1992PAZh...18..777G)
d = Bersier (2002ApJS..140..465B 2002ApJS..140..465B)
e = Metzger et al. (1991ApJS...76..803M 1991ApJS...76..803M)
f = Coulson & Caldwell (1985SAAOC...9....5C 1985SAAOC...9....5C)
g = Metzger et al. (1992AJ....103..529M 1992AJ....103..529M)
h = Pont et al. (1994A&AS..105..165P 1994A&AS..105..165P)
i = Imbert (1999A&AS..140...79I 1999A&AS..140...79I, Cat. J/A+AS/140/79)
j = Storm et al. (2004A&A...415..531S 2004A&A...415..531S, Cat. J/A+A/415/531)
V = VELOCE (Anderson et al. in prep.)
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Byte-by-byte Description of file: table2-4.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 17 A17 --- Cluster Cluster name
19- 25 F7.3 deg RAdeg Cluster center right ascension (J2000)
27- 34 F8.4 deg DEdeg Cluster center declination (J2000)
37- 40 I4 --- Nmemb Number of cluster members
42- 45 I4 uas plxCl Cluster parallax including the Lindegren et
al. (2021A&A...649A...4L 2021A&A...649A...4L) offset correction
47- 48 I2 uas e_plxCl Cluster parallax uncertainty
50- 55 F6.3 mas/yr pmRACl Cluster proper motion in right ascension
direction, pmRA*cosDE
57- 61 F5.3 mas/yr s_pmRACl Cluster proper motion dispersion in
right ascension direction
63- 68 F6.3 mas/yr pmDECl Cluster proper motion in declination
70- 74 F5.3 mas/yr s_pmDECl Cluster proper motion in dispersion
declination
76- 84 A9 --- Cepheid Cepheid name
85 A1 --- f_Cepheid [+] ATO J297 = ATO J297.7863+25.3136
86 A1 --- n_Cepheid [*] * for first overtone pulsator
88- 91 I4 uas plxCep Cepheid parallax including the Lindegren et
al. (2021A&A...649A...4L 2021A&A...649A...4L) offset correction
93- 94 I2 uas e_plxCep Cepheid parallax error
96-101 F6.3 mas/yr pmRACep Cepheid proper motion in right ascension
direction, cosDE
103-107 F5.3 mas/yr e_pmRACep Cepheid proper motion standard error in
right ascension direction
109-114 F6.3 mas/yr pmDECep Cepheid proper motion in declination
direction
116-120 F5.3 mas/yr e_pmDECep Cepheid proper motion standard error in
declination direction
122-126 F5.2 pc Sep Projected separation of the Cepheid from
cluster center
128-131 F4.2 --- Pmemb Membership probability
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Byte-by-byte Description of file: table7.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- Cepheid Cepheid name
12- 30 F19.16 d Per Cepheid pulsation period
33- 51 I19 --- GaiaDR3 Gaia DR3 source ID
53- 57 F5.3 mas plx Gaia DR3 parallax
59- 63 F5.3 mas plxCorr Gaia DR3 parallax including the Lindegren et
al. (2021A&A...649A...4L 2021A&A...649A...4L) offset correction
65 A1 --- WH [Y] Wesenheit WH magnitude used (1)
67 A1 --- WG [Y] Wesenheit WG magnitude used (1)
69 A1 --- BP [Y] Gaia BP magnitude used (1)
71 A1 --- V [Y] V magnitude used (1)
73 A1 --- G [Y] Gaia G magnitude used (1)
75 A1 --- RP [Y] Gaia RP magnitude used (1)
77 A1 --- F160W [Y] F160W magnitude used (1)
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Note (1): Y if the source was used for the calibration of the Leavitt Law,
otherwise is empty.
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Byte-by-byte Description of file: table10.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 A9 --- Cepheid Cepheid name
11- 16 F6.3 d Per Cepheid pulsation period
18- 23 F6.1 uas plx Host cluster parallax
25- 27 F3.1 uas sigmastat Statistical uncertainty in cluster parallax
29- 31 F3.1 uas sigmacov Angular covariance in cluster parallax
33- 35 F3.1 uas sigmatot Sum in quadrature of sigma_stat and sigma_cov
37- 41 F5.3 mag WG ?=- Wesenheit WG magnitude, WD=G-1.921(Bp-Rp)
43- 47 F5.3 mag e_WG ?=- Uncertainty in Wesenheit WG magnitude
49- 53 F5.3 mag WHa ?=- Wesenheit WH magnitude,
WH=F160W-0.386(F555W-F814W, without CRNL
corrections
55- 59 F5.3 mag e_WHa ?=- Uncertainty in Wesenheit WH magnitude
61- 65 F5.2 --- [Fe/H] ?=- Iron abundance
67- 70 F4.2 --- e_[Fe/H] ?=- Uncertainty in iron abundance
72- 75 A4 --- r_[Fe/H] Reference of the iron abundance (1)
77- 81 F5.3 mag E(B-V) ?=- Color excess value
83- 87 F5.3 mag e_E(B-V) ?=- Uncertainty in the color excess
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Note (1): References as follows:
LL11 = Luck & Lambert (2011AJ....142..136L 2011AJ....142..136L, Cat. J/AJ/142/136)
G14 = Genovali et al. (2014A&A...566A..37G 2014A&A...566A..37G, Cat. J/A+A/566/A37)
L11 = Luck et al. (2011AJ....142...51L 2011AJ....142...51L, Cat. J/AJ/142/51)
G15 = Genovali et al. (2015A&A...580A..17G 2015A&A...580A..17G, Cat. J/A+A/580/A17)
R08 = Romaniello et al. (2022A&A...658A..29R 2022A&A...658A..29R, Cat. J/A+A/658/A29)
L07 = Lemasle et al. (2007A&A...467..283L 2007A&A...467..283L)
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Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
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1- 17 A17 --- Cluster Cluster name
19- 37 I19 --- GaiaDR3 Gaia EDR3 source id
39- 44 F6.4 mas plx Gaia EDR3 parallax
46- 52 F7.4 mas Corr Lindegren et al. (2021A&A...649A...4L 2021A&A...649A...4L)
parallax offset correction
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Acknowledgements:
Mauricio Cruz, mauricio.cruz(at)correo.nucleares.unam.mx
(End) Patricia Vannier [CDS] 03-Feb-2023