J/ApJ/826/56 HST/WFC3 obs. of Cepheids in SN Ia host gal. (Riess+, 2016)
A 2.4% determination of the local value of the Hubble constant.
Riess A.G., Macri L.M., Hoffmann S.L., Scolnic D., Casertano S.,
Filippenko A.V., Tucker B.E., Reid M.J., Jones D.O., Silverman J.M.,
Chornock R., Challis P., Yuan W., Brown P.J., Foley R.J.
<Astrophys. J., 826, 56-56 (2016)>
=2016ApJ...826...56R 2016ApJ...826...56R (SIMBAD/NED BibCode)
ADC_Keywords: Photometry, HST ; Supernovae ; Stars, variable ; Galaxies, IR
Keywords: cosmological parameters; cosmology: observations; distance scale;
galaxies: distances and redshifts
Abstract:
We use the Wide Field Camera 3 (WFC3) on the Hubble Space Telescope
(HST) to reduce the uncertainty in the local value of the Hubble
constant from 3.3% to 2.4%. The bulk of this improvement comes from
new near-infrared (NIR) observations of Cepheid variables in 11 host
galaxies of recent type Ia supernovae (SNe Ia), more than doubling the
sample of reliable SNe Ia having a Cepheid-calibrated distance to a
total of 19; these in turn leverage the magnitude-redshift relation
based on ∼300 SNe Ia at z<0.15. All 19 hosts as well as the megamaser
system NGC 4258 have been observed with WFC3 in the optical and NIR,
thus nullifying cross-instrument zeropoint errors in the relative
distance estimates from Cepheids. Other noteworthy improvements
include a 33% reduction in the systematic uncertainty in the maser
distance to NGC 4258, a larger sample of Cepheids in the Large
Magellanic Cloud (LMC), a more robust distance to the LMC based on
late-type detached eclipsing binaries (DEBs), HST observations of
Cepheids in M31, and new HST-based trigonometric parallaxes for Milky
Way (MW) Cepheids. We consider four geometric distance calibrations of
Cepheids: (i) megamasers in NGC 4258, (ii) 8 DEBs in the LMC, (iii) 15
MW Cepheids with parallaxes measured with HST/FGS, HST/WFC3 spatial
scanning and/or Hipparcos, and (iv) 2 DEBs in M31. The Hubble constant
from each is 72.25±2.51, 72.04±2.67, 76.18±2.37, and
74.50±3.27km/s/Mpc, respectively. Our best estimate of
H0=73.24±1.74km/s/Mpc combines the anchors NGC 4258, MW, and LMC,
yielding a 2.4% determination (all quoted uncertainties include fully
propagated statistical and systematic components). This value is
3.4σ higher than 66.93±0.62km/s/Mpc predicted by ΛCDM
with 3 neutrino flavors having a mass of 0.06eV and the new Planck
data, but the discrepancy reduces to 2.1σ relative to the
prediction of 69.3±0.7km/s/Mpc based on the comparably precise
combination of WMAP+ACT+SPT+BAO observations, suggesting that
systematic uncertainties in CMB radiation measurements may play a role
in the tension. If we take the conflict between Planck high-redshift
measurements and our local determination of H0 at face value, one
plausible explanation could involve an additional source of dark
radiation in the early universe in the range of ΔNeff∼0.4-1.
We anticipate further significant improvements in H0 from upcoming
parallax measurements of long-period MW Cepheids.
Description:
The SH0ES (SNe, H0, for the Equation of State of dark energy) program
has been selecting SNe Ia with the qualities detailed in section 2 to
ensure a reliable calibration of their fiducial luminosity. The result
is a nearly complete sample of 19 objects observed between 1993 and
2015 (see Table 1).
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 50 20 Cepheid hosts observed with HST/WFC3
table4.dat 68 1486 HST WFC3-IR Cepheids
table8.dat 110 210 Fits for H0
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See also:
B/hst : HST Archived Exposures Catalog (STScI, 2007)
J/ApJ/817/128 : Megamaser Cosmology Project. VIII. NGC5765B (Gao+, 2016)
J/ApJ/812/31 : Local Star Formation effects on type Ia SNe (Jones+, 2015)
J/MNRAS/451/724 : PHAT. XIII. M31 Cepheid P-L relation (Wagner-Kaiser+, 2015)
J/AJ/149/117 : LMC infrared survey. I. Photometry of Cepheids (Macri+, 2015)
J/ApJ/799/144 : M31 Cepheids in near-IR (Kodric+, 2015)
J/A+A/568/A22 : Joint analysis of the SDSS-II & SNLS SNe Ia (Betoule+, 2014)
J/ApJ/777/79 : HST photometry of Cepheid candidates in M101 (Mager+, 2013)
J/ApJS/208/20 : Nine-year WMAP point source catalogs (Bennett+, 2013)
J/ApJ/745/156 : M31 Cepheids with HST/WFC3 (Riess+, 2012)
J/ApJ/730/119 : HST/WFC3 obs. of Cepheids in SN Ia hosts (Riess+, 2011)
J/A+A/523/A7 : Light curves of type Ia supernovae in SNLS (Guy+, 2010)
J/ApJ/722/566 : Host gal. of SNe Ia in SDSS-II SN survey (Lampeitl+, 2010)
J/MNRAS/406/782 : Type Ia supernovae luminosities (Sullivan+, 2010)
J/ApJ/700/1097 : Light curve parameters of SN Ia (Hicken+, 2009)
J/ApJS/183/109 : Cepheids in 3 host galaxies (Riess+, 2009)
J/ApJ/700/331 : Light curves of type Ia supernovae (CfA3) (Hicken+, 2009)
J/ApJ/699/539 : Cepheids in SN-Ia host galaxies (Riess+, 2009)
J/AcA/58/163 : VI light curves of LMC classical Cepheids (Soszynski+, 2008)
J/ApJ/659/1040 : VLBI monitoring of NGC 4258 (Argon+, 2007)
J/ApJ/659/122 : Improved distances to type Ia supernovae (Jha+, 2007)
J/ApJ/652/1133 : BVI photometry of NGC 4258 Cepheids (Macri+, 2006)
J/ApJ/645/488 : SN type Ia luminosities (Wang+, 2006)
J/ApJ/627/579 : Photometry of variables in NGC 3370 (Riess+, 2005)
J/AJ/128/2239 : JHKs photometry of 92 LMC Cepheids (Persson+, 2004)
J/ApJ/591/L111 : Period of Cepheids in M 83 (Bonanos+, 2003)
J/AJ/115/1016 : M31B eclipsing binaries and Cepheids (Kaluzny+ 1998)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 5 A5 --- Gal Galaxy name
7 A1 --- f_Gal [d] Flag on Gal (1)
9- 14 A6 --- SN SN Ia name
16- 20 I5 s IRexp NIR exposure time obtained with WFC3/IR
and F160W
22- 26 I5 s Oexp Optical exposure time (2)
28- 38 A11 --- PID Proposal IDs
40- 50 A11 "Y/M/D" Date UT date of first WFC3/IR observation
--------------------------------------------------------------------------------
Note (1):
d = Includes time-series data from an earlier program and a different camera;
see Figure 2.
Note (2): Data obtained with WFC3/UVIS and F555W, F814W, or F350LP used to
find and measure the flux of Cepheids.
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 5 A5 --- Gal Observed field
7- 16 F10.6 deg RAdeg Right ascension in decimal degrees (J2000)
18- 29 F12.8 deg DEdeg Declination in decimal degrees (J2000)
31- 38 A8 --- ID Cepheid identifier
40- 45 F6.3 d Per [3/99] Cepheid period
47- 50 F4.2 mag V-I [0.5/2.5] HST/WFC3 F555W-F814W color index
52- 56 F5.2 mag F160W [16/26.8] HST/WFC3 F160W magnitude
58- 61 F4.2 mag sigTot [0.1/0.8] Total statistical uncertainty in
Cepheid magnitude
64- 68 F5.3 [-] [O/H] [8.4/9.4] Metallicity estimate, 12+log(0/H),
position based, Hoffmann et al. in prep.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table8.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 F4.2 --- chi2 [0.8/1.5] Reduced χ2dof
6- 10 F5.2 km/s/Mpc H0 [70.7/79.3] Hubble constant
12- 15 F4.2 km/s/Mpc e_H0 [1/4] Uncertainty in H0 (1)
19- 21 A3 --- Anc Anchors (2)
23- 24 A2 --- Brk Break in Cepheid P-L relation (3)
26- 26 A1 --- Clp Clipping procedure (4)
28- 30 F3.1 --- Clt [2.7/3.5]? Clipping threshold, σ;
Blank=No clipping
32- 32 A1 --- Opt [YN] Optical completeness required
34- 36 A3 --- PL Form of Cepheid P-L relation used (5)
38- 38 A1 --- R [CFN] Redding Law (6)
40- 42 F3.1 --- RV [2.5/3.3] Extinction-law parameter
44- 47 I4 --- N [1203/3138] Number of Cepheids fit
49- 49 A1 --- Zs [BZ] Metallicity scale (7)
51- 55 F5.2 --- gamma [-0.3/-0.06]? Change in Wesenheit mag/log(O/H)
57- 60 F4.2 --- e_gamma [0.05/0.2]? Uncertainty in γ
62- 67 F6.3 --- b [-3.4/-2.9]? Slope of Cepheid P-L for all P in
no-break variants; for P>10d for two-slope
variants (in mag/[-])
69- 72 F4.2 --- e_b [0.01/0.04]? Uncertainty in b
74- 79 F6.3 --- bl [-4.2/-3.1]? Slope of Cepheid P-L for P<10d
(in mag/[-])
81- 84 F4.2 --- e_bl [0.02/0.06]? Uncertainty in bl
86- 86 A1 --- SN [MS] Light-curve fitter (S=SALT or M=MLCS2k2)
88- 93 F6.4 --- zm [0.01/0.03] Minimum z used in SN Hubble diagram
95-100 F6.2 mag MX0 [-19.4/-19] SN absolute magnitude (8)
102-108 F7.5 0.2mag aX [0.70/0.72] Intercept of SN Hubble diagram (8)
110-110 A1 --- Gal [ALS] SN host galaxy sample;
A=All, S=Spiral, L=high LSF
--------------------------------------------------------------------------------
Note (1): H0 error listed from fit for MX0 in equation 9 (section 3.1.1)
or mx,42580 in equation 4 (section 3) only.
Note (2): Anchors as follows:
N = NGC 4258 Masers;
M = Milky Way Parallaxes;
L = LMC detached eclipsing binaries;
NML = primary fit using all three;
A = NML+M31 detached eclipsing binaries.
Note (3): Break in P-L relation as follows:
Y = two-slope solution, unitless;
N = single-slope solution, unitless;
10 = single slope restricted to P>10d, unit=d;
60 = single slope restricted to P<60d, unit=d.
Note (4): Clipping procedure as follows:
G = global;
I = individual;
1 = global but removing single largest outlier at a time.
Note (5): Form of P-L relation as follows:
W_H = NIR Wesenheit;
H = NIR without extinction correction;
W_I = Optical Wesenheit.
Note (6): Reddening law as follows:
F = Fitzpatrick (1999PASP..111...63F 1999PASP..111...63F);
C = Cardelli et al. (1989ApJ...345..245C 1989ApJ...345..245C);
N = Nataf et al. (2016MNRAS.456.2692N 2016MNRAS.456.2692N).
Note (7): Metallicity scale as follows:
Z = traditional R_23 method, Zaritsky et al. (1994ApJ...420...87Z 1994ApJ...420...87Z);
B = T_e method, Bresolin (2011ApJ...729...56B 2011ApJ...729...56B).
Note (8): X in MX0 and aX stands for B or V depending on the SN fitter,
see text.
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History:
From electronic version of the journal
References:
Riess et al. Companion Paper. 2016ApJ...830...10H 2016ApJ...830...10H Cat. J/ApJ/830/10
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 22-Sep-2016