Supernova Host Research Articles

Linking Transients to their Host Galaxies: II. A Comparison of Host Galaxy Properties and Rate Dependencies across Supernova Types

Abstract We use the latest dataset of supernova (SN) host galaxies to investigate how the host properties – stellar mass, star formation rate, metallicity, absolute magnitude, and colour – differ across SN types, with redshift-driven selection effects controlled. SN Ib and Ic host galaxies, on average, are more massive, metal-rich, and redder than SN II hosts. For subtypes, SN Ibn and Ic-BL have bluer hosts than their normal SN Ib and Ic siblings; SN IIb has consistent host properties with SN Ib, while hosts of SN IIn are more metal-rich than those of SN II. Hydrogen-deficient superluminous supernovae feature bluer and lower luminosity hosts than most subtypes of core-collapse supernova (CC SN). Assuming simple proportionality of CC SN rates and host star formation rates (SFRs) does not recover the observed mean host properties; either a population of long-lived progenitors or a metallicity-dependent SN production efficiency better reproduces the observed host properties. Assuming the latter case, the rates of SN II are insensitive to host metallicity, but the rates of SN Ib and Ic are substantially enhanced in metal-rich hosts by a factor of ∼10 per dex increase in metallicity. Hosts of SN Ia are diverse in their observed properties; subtypes including SN Ia-91T, Ia-02cx, and Ia-CSM prefer star-forming hosts, while subtypes like SN Ia-91bg and Ca-rich prefer quiescent hosts. The rates of SN Ia-91T, Ia-02cx, and Ia-CSM are closely dependent on, or even proportional to, their host SFRs, indicating relatively short-lived progenitors. Conversely, the rates of SN Ia-91bg and Ca-rich transients are proportional to the total stellar mass, favoring long-lived progenitors.

Luminosity Functions of the Host Galaxies of Supernova

We present the luminosity functions and stellar mass functions of supernova (SN) host galaxies and test if they differ from the functions of normal field galaxies. We utilize homogeneous samples consisting of 273 SNe Ia (z ≤ 0.3) and 44 core-collapse (CC) SNe (z ≤ 0.1) from the Sloan Digital Sky Survey II Supernova Survey and the high-signal-to-noise-ratio photometry of galaxies from the Hyper Suprime-Cam Subaru Strategic Program. SN hosts are classified into star-forming and passive galaxy groups based on the spectral energy distribution fitting. We find that the SN host luminosity functions and stellar mass functions deviate from those of normal field galaxies. Star-forming galaxies dominate the low-mass end of the SN Ia host mass function, while passive galaxies dominate the high-mass end. CC SNe are predominantly hosted by star-forming galaxies. In addition, intermediate-mass hosts produce CC SNe with the highest efficiency, while the efficiency of producing SNe Ia monotonically increases as the hosts become more massive. Furthermore, we derive the pseudo mass normalized SN rates (pSNuM) based on the mass functions. We find that the star-forming component of pSNuM Ia is less sensitive to the changes in stellar mass, in comparison with the total rate. The behavior of pSNuM CC suggests that the CC rate is proportional to the star-forming rate.

Cosmological Inference from within the Peculiar Local Universe

The existence of ‘peculiar’ velocities due to the formation of cosmic structure marks a point of discord between the real universe and the usually assumed Friedmann–Lemaítre–Robertson–Walker metric, which accomodates only the smooth Hubble expansion on large scales. In the standard ΛCDM model framework, Type Ia supernovae data are routinely “corrected” for the peculiar velocities of both the observer and the supernova host galaxies relative to the cosmic rest frame, in order to infer evidence for acceleration of the expansion rate from their Hubble diagram. However, observations indicate a strong, coherent local bulk flow that continues outward without decaying out to a redshift z≳0.1, contrary to the ΛCDM expectation. By querying the halo catalogue of the Dark Sky Hubble-volume N-body simulation, we find that an observer placed in an unusual environment like our local universe should see correlations between supernovae in the JLA catalogue that are 2–8 times stronger than seen by a typical or Copernican observer. This accounts for our finding that peculiar velocity corrections have a large impact on the value of the cosmological constant inferred from supernova data. We also demonstrate that local universe-like observers will infer a downward biased value of the clustering parameter S8 from comparing the density and velocity fields. More realistic modelling of the peculiar local universe is thus essential for correctly interpreting cosmological data.

Tip of the Red Giant Branch Distances with JWST: An Absolute Calibration in NGC 4258 and First Applications to Type Ia Supernova Hosts

The tip of the red giant branch (TRGB) allows for the measurement of precise and accurate distances to nearby galaxies based on the brightest ascent of low-mass red giant branch stars before they undergo the helium flash. With the advent of JWST, there is great promise to utilize the technique to measure galaxy distances out to at least 50 Mpc, significantly further than the Hubble Space Telescope's (HST's) reach of 20 Mpc. However, with any standard candle, it is first necessary to provide an absolute reference. Here, we use Cycle 1 data to provide an absolute calibration in the F090W filter. F090W is most similar to the F814W filter commonly used for TRGB measurements with HST, which had been adopted by the community due to its minimal dependence on the underlying metallicities and ages of stars. The imaging we use was taken in the outskirts of NGC 4258, which has a direct geometrical distance measurement from the Keplerian motion of its water megamaser. Utilizing several measurement techniques, we find MTRGBF090W = −4.362 ± 0.033 (stat) ± 0.045 (sys) mag (Vega) for the metal-poor TRGB. We also perform measurements of the TRGB in two Type Ia supernova hosts, NGC 1559 and NGC 5584. We find good agreement between our TRGB distances and previous determinations of distances to these galaxies from Cepheids (Δ = 0.01 ± 0.06 mag), with these differences being too small to explain the Hubble tension (∼0.17 mag). In addition, we showcase the serendipitous discovery of a faint dwarf galaxy near NGC 5584.

The JWST Discovery of the Triply Imaged Type Ia “Supernova H0pe” and Observations of the Galaxy Cluster PLCK G165.7+67.0

A Type Ia supernova (SN) at z = 1.78 was discovered in James Webb Space Telescope Near Infrared Camera imaging of the galaxy cluster PLCK G165.7+67.0 (G165; z = 0.35). The SN is situated 1.5–2 kpc from the host-galaxy nucleus and appears in three different locations as a result of gravitational lensing by G165. These data can yield a value for Hubble’s constant using time delays from this multiply imaged SN Ia that we call “SN H0pe.” Over the cluster, we identified 21 image multiplicities, confirmed five of them using the Near-Infrared Spectrograph, and constructed a new lens model that gives a total mass within 600 kpc of (2.6 ± 0.3) × 1014 M ⊙. The photometry uncovered a galaxy overdensity coincident with the SN host galaxy. NIRSpec confirmed six member galaxies, four of which surround the SN host galaxy with relative velocity ≲900 km s−1 and projected physical extent ≲33 kpc. This compact galaxy group is dominated by the SN host galaxy, which has a stellar mass of (5.0 ± 0.1) × 1011 M ⊙. The group members have specific star formation rates of 2–260 Gyr−1 derived from the Hα-line fluxes corrected for stellar absorption, dust extinction, and slit losses. Another group centered on a strongly lensed dusty star-forming galaxy is at z = 2.24. The total (unobscured and obscured) SFR of this second galaxy group is estimated to be (≳ 100 M ⊙ yr−1), which translates to a supernova rate of ∼1 SNe yr−1, suggesting that regular monitoring of this cluster may yield additional SNe.

WiFeS observations of nearby southern Type Ia supernova host galaxies

Abstract We present high-resolution observations of nearby ( $z\lesssim0.1$ ) galaxies that have hosted Type Ia supernovae to measure systemic spectroscopic redshifts using the wide field spectrograph (WiFeS) instrument on the Australian National University 2.3 m telescope at Siding Spring Observatory. While most of the galaxies targeted have previous spectroscopic redshifts, we provide demonstrably more accurate and precise redshifts with competitive uncertainties, motivated by potential systematic errors that could bias estimates of the Hubble constant ( $H_0$ ). The WiFeS instrument is remarkably stable; after calibration, the wavelength solution varies by $\lesssim$ 0.5 Å in red and blue with no evidence of a trend over the course of several years. By virtue of the $25\times 38$ arcsec field of view, we are always able to measure the redshift of the galactic core, or the entire galaxy in the cases where its angular extent is smaller than the field of view, reducing any errors due to galaxy rotation. We observed 185 southern SN Ia host galaxies and measured the redshift of each via at least one spatial region of (a) the core and (b) the average over the full-field/entire galaxy. Overall, we find stochastic differences between historical redshifts and our measured redshifts on the order of $\lesssim10^{-3}$ with a mean offset of 4.3 ${\times 10^{-5}}$ and normalised median absolute deviation of 1.2 ${\times 10^{-4}}$ . We show that a systematic redshift offset at this level is not enough to bias cosmology, as $H_0$ shifts by $+0.1$ km s $^{-1}$ Mpc $^{-1}$ when we replace Pantheon+ redshifts with our own, but the occasional large differences are interesting to note.

A sample of dust attenuation laws for Dark Energy Survey supernova host galaxies

Context. Type Ia supernovae (SNe Ia) are useful distance indicators in cosmology, provided their luminosity is standardized by applying empirical corrections based on light-curve properties. One factor behind these corrections is dust extinction, which is accounted for in the color–luminosity relation of the standardization. This relation is usually assumed to be universal, which can potentially introduce systematics into the standardization. The “mass step” observed for SN Ia Hubble residuals has been suggested as one such systematic. Aims. We seek to obtain a more complete view of dust attenuation properties for a sample of 162 SN Ia host galaxies and to probe their link to the mass step. Methods. We inferred attenuation laws toward hosts from both global and local (4 kpc) Dark Energy Survey photometry and composite stellar population model fits. Results. We recovered a relation between the optical depth and the attenuation slope, best explained by differing star-to-dust geometry for different galaxy orientations, which is significantly different from the optical depth and extinction slope relation observed directly for SNe. We obtain a large variation of attenuation slopes and confirm these change with host properties, such as the stellar mass and age, meaning a universal SN Ia correction should ideally not be assumed. Analyzing the cosmological standardization, we find evidence for a mass step and a two-dimensional “dust step”, both more pronounced for red SNe. Although comparable, the two steps are not found to be completely analogous. Conclusions. We conclude that host galaxy dust data cannot fully account for the mass step, using either an alternative SN standardization with extinction proxied by host attenuation or a dust-step approach.

Standardized Luminosity of the Tip of the Red Giant Branch Utilizing Multiple Fields in NGC 4258 and the CATs Algorithm

The tip of the red giant branch provides a luminous standard candle for calibrating distance ladders that reach Type Ia supernova (SN Ia) hosts. However, recent work reveals that tip measurements vary at the ∼0.1 mag level for different stellar populations and locations within a host, which may lead to inconsistencies along the distance ladder. We pursue a calibration of the tip using 11 Hubble Space Telescope fields around the maser host, NGC 4258, that is consistent with SN Ia hosts by standardizing tip measurements via their contrast ratios. We find F814W-band tips that exhibit a full 0.3 mag range and 0.1 mag dispersion. We do not find any correlation between H i column density and the apparent tip to 0.04 ± 0.03 mag/cm−2. We search for a tip–contrast relation (TCR) and measure the TCR within the fields of NGC 4258 of −0.015 ± 0.008 mag/R, where R is the contrast ratio. This value is consistent with the TCR originally discovered in the GHOSTS sample of −0.023 ± 0.005 mag/R. Combining these measurements, we find a global TCR of −0.021 ± 0.004 mag/R and a calibration of mag. We also use stellar models to simulate single age and metallicity stellar populations with [Fe/H] from −2.0 to −0.7 and ages from 3 to 12 Gyr and reconstruct the global TCR found here to a factor of ∼2. This work is combined in a companion analysis with tip measurements of nearby SN Ia hosts to measure H 0.

Iron-rich Metal-poor Stars and the Astrophysics of Thermonuclear Events Observationally Classified as Type Ia Supernovae. I. Establishing the Connection

The progenitor systems and explosion mechanisms responsible for the thermonuclear events observationally classified as Type Ia supernovae are uncertain and difficult to uniquely constrain using traditional observations of Type Ia supernova host galaxies, progenitors, light curves, and remnants. For the subset of thermonuclear events that are prolific producers of iron, we use published theoretical nucleosynthetic yields to identify a set of elemental abundance ratios infrequently observed in metal-poor stars but shared across a range of progenitor systems and explosion mechanisms: [Na, Mg, Co/Fe] < 0. We label stars with this abundance signature “iron-rich metal-poor,” or IRMP stars. We suggest that IRMP stars formed in environments dominated by thermonuclear nucleosynthesis and consequently that their elemental abundances can be used to constrain both the progenitor systems and explosion mechanisms responsible for thermonuclear explosions. We identify three IRMP stars in the literature and homogeneously infer their elemental abundances. We find that the elemental abundances of BD +80 245, HE 0533–5340, and SMSS J034249.53–284216.0 are best explained by the (double) detonations of sub-Chandrasekhar-mass CO white dwarfs. If our interpretation of IRMP stars is accurate, then they should be very rare in globular clusters and more common in the Magellanic Clouds and dwarf spheroidal galaxies than in the Milky Way’s halo. We propose that future studies of IRMP stars will quantify the relative occurrences of different thermonuclear event progenitor systems and explosion mechanisms.

Connecting Infrared Surface Brightness Fluctuation Distances to Type Ia Supernova Hosts: Testing the Top Rung of the Distance Ladder

We compare infrared surface brightness fluctuation (IR SBF) distances measured in galaxies that have hosted type Ia supernovae (SNe Ia) to distances estimated from SNe Ia light-curve fits. We show that the properties of the SNe Ia found in IR SBF hosts are very different from those exploding in Cepheid calibrators, therefore this is a direct test of systematic uncertainties on the estimation of the Hubble constant (H 0) using SNe. The IR SBF results from Jensen et al. provide a large and uniformly measured sample of IR SBF distances which we directly compare with the distances to 25 SN Ia host galaxies. We divide the Hubble flow SNe Ia into subsamples that best match the divergent SN properties seen in the IR SBF hosts and Cepheid hosts. We further divide the SNe Ia into a sample with light-curve widths and host masses that are congruent to those found in the SBF-calibrated hosts. We refit the light-curve stretch and color correlations with luminosity, and use these revised parameters to calibrate a sample of “Hubble flow” SNe Ia with IR SBF calibrators. Relative to the Hubble flow sample, the average calibrator distance moduli vary by 0.03 mag depending on the SN Ia subsample examined and this adds a 1.8% systematic uncertainty to our Hubble constant estimate. Based on the IRSBF calibrators, H 0 = 74.6 ± 0.9(stat) ± 2.7(syst) km s−1 Mpc−1, which is consistent with the Hubble constant derived from SNe Ia calibrated from Cepheid variables. We conclude that IR SBFs provide reliable calibration of SNe Ia with a precision comparable to Cepheid calibrators, and with a significant saving in telescope time.

Metallicity beats sSFR: the connection between superluminous supernova host galaxy environments and the importance of metallicity for their production

ABSTRACT We analyse 33 Type I superluminous supernovae (SLSNe) taken from Zwicky Transient Facility (ZTF)’s Bright Transient Survey to investigate the local environments of their host galaxies. We use a spectroscopic sample of galaxies from the Sloan Digital Sky Survey (SDSS) to determine the large-scale environmental density of the host galaxy. Noting that SLSNe are generally found in galaxies with low stellar masses, high star formation rates (SFRs), and low metallicities, we find that SLSN hosts are also rarely found within high-density environments. Only $3\substack{+9 \\ -1}$ per cent of SLSN hosts were found in regions with two or more bright galaxies within 2 Mpc. For comparison, we generate a sample of 662 SDSS galaxies matched to the photometric properties of the SLSN hosts. This sample is also rarely found within high-density environments, suggesting that galaxies with properties required for SLSN production favour more isolated environments. Furthermore, we select galaxies within the IllustrisTNG simulation to match SLSN host galaxy properties in colour and stellar mass. We find that the fraction of simulated galaxies in high-density environments quantitatively match the observed SLSN hosts only if we restrict to simulated galaxies with metallicity 12 + log (O/H) ≤ 8.12. In contrast, limiting to only the highest specific star formation rate (sSFR) galaxies in the sample leads to an overabundance of SLSN hosts in high-density environments. Thus, our measurement of the environmental density of SLSN host galaxies appears to break the degeneracy between low metallicity and high sSFR as the driver for SLSN hosts and provides evidence that the most constraining factor on SLSN production is low metallicity.

Finding LoTSS of hosts for GRBs: a search for galaxy–gamma-ray burst coincidences at low frequencies with LOFAR

ABSTRACT The LOFAR (Low Frequency Array) Two-metre Sky Survey (LoTSS) is an invaluable new tool for investigating the properties of sources at low frequencies and has helped to open up the study of galaxy populations in this regime. In this work, we perform a search for host galaxies of gamma-ray bursts (GRBs). We use the relative density of sources in Data Release 2 (DR2) of LoTSS to define the probability of a chance alignment, Pchance, and find 18 sources corresponding to 17 GRBs that meet a Pchance &amp;lt; 1 per cent criterion. We examine the nature and properties of these radio sources using both LOFAR data and broad-band information, including their radio spectral index, star formation rate estimates, and any contributions from active galactic nucleus emission. Assuming that the radio emission is dominated by star formation, we find that our sources show high star formation rates (101–103 M⊙ yr−1) compared with both a field galaxy sample and a sample of core-collapse supernova hosts, and the majority of putative hosts are consistent with ultra-luminous infrared galaxy classifications. As a result of our analyses, we define a final sample of eight likely GRB host candidates in the LoTSS DR2 survey.

Examining the Properties of Low-luminosity Hosts of Type Ia Supernovae from ASAS-SN

We present a spectroscopic analysis of 44 low-luminosity host galaxies of Type Ia supernovae (SNe Ia) detected by the All-Sky Automated Survey for Supernovae (ASAS-SN), using hydrogen, oxygen, and sulfur emission lines to measure metallicities and star formation rates. We find no statistically significant evidence that the star formation activity and metallicities of the galaxies in our sample are inconsistent with galaxies of similar luminosities and masses. We identify two 3σ outlier galaxies that have high metallicities for their stellar masses, but find that their other properties are consistent with general galaxies. The overall consistency between our sample and general galaxy samples further strengthens the evidence from more luminous SN Ia host galaxy samples that SN Ia host galaxies are typical.

Synthetic Population of Binary Cepheids. II. The Effect of Companion Light on the Extragalactic Distance Scale

Because of their period–luminosity relation (PLR), classical Cepheids play a key role in the calibration of the extragalactic distance scale and the determination of the Hubble–Lemaître constant H 0. Recent findings show that the majority of classical Cepheids should be in binary or multiple systems, which might undermine their accuracy, as the extra—and unaccounted for—light from the companions of Cepheids causes a shift in the PLR. We quantify this shift using synthetic populations of binary Cepheids that we developed for this purpose, as described in Paper I of this series. We find that while all PLRs are shifted toward brighter values due to the excess light from the companions, the bias in the relative distance modulus between two galaxies hosting binary Cepheids can be either positive or negative, depending on the percentage of binary Cepheids in them. If the binarity percentage in the two galaxies is similar, the effect of binarity is canceled. Otherwise, it introduces a shift in the distance modulus of the order of millimagnitudes in the near-infrared passbands and Wesenheit indices, and tens of millimagnitudes in the visual domain; its exact value depends on the variant of the synthetic population (a unique combination of metallicity, star formation history, shape and location of the instability strip, and initial parameter distributions). Such shifts in the distance moduli to Type Ia supernova host galaxies introduce an additional statistical error on H 0, which however does not prevent measuring H 0 with a precision of 1%.

Using 4MOST to refine the measurement of galaxy properties: a case study of supernova hosts

Abstract The Rubin Observatory’s 10-yr Legacy Survey of Space and Time will observe near to 20 billion galaxies. For each galaxy the properties can be inferred. Approximately 105 galaxies observed per year will contain Type Ia supernovae (SNe), allowing SN host-galaxy properties to be calculated on a large scale. Measuring the properties of SN host galaxies serves two main purposes. The first is that there are known correlations between host galaxy type and SN type, which can be used to aid in the classification of SNe. Secondly, Type Ia SNe exhibit correlations between host-galaxy properties and the peak luminosities of the SNe, which has implications for their use as standardizable candles in cosmology. We have used simulations to quantify the improvement in host-galaxy stellar mass (M*) measurements when supplementing photometry from Rubin with spectroscopy from the 4-metre Multi-Object Spectroscopic Telescope (4MOST) instrument. We provide results in the form of expected uncertainties in M* for galaxies with 0.1 &amp;lt; z &amp;lt; 0.9 and 18 &amp;lt; rAB &amp;lt; 25. We show that for galaxies mag 22 and brighter, combining Rubin and 4MOST data reduces the uncertainty measurements of galaxy M* by more than a factor of 2 compared with Rubin data alone. This applies for elliptical and Sc-type hosts. We demonstrate that the reduced uncertainties in M* lead to an improvement of 7 per cent in the precision of the ‘mass step’ correction. We expect our improved measurements of host-galaxy properties to aid in the photometric classification of SNe observed by Rubin.

A First Look at Cepheids in a Type Ia Supernova Host with JWST

We report the first look at extragalactic Cepheid variables with the James Webb Space Telescope (JWST), obtained from an archival observation of NGC 1365, host of SNIa 2012fr, a calibration path used to measure the Hubble constant. As expected, the high-resolution observations with NIRCam through F200W show better source separation from line-of-sight companions than Hubble Space Telescope (HST) images at similar near-infrared wavelengths, the spectral region that has been used to mitigate the impact of host dust on distance measurements. Using the standard star P330E as a zero-point and point-spread function reference, we photometered 31 previously known Cepheids in the JWST field, spanning including 24 Cepheids in the longer-period interval of . We compared the resultant period–luminosity (P-L) relations to that of 49 Cepheids in the full period range including 38 in the longer-period range observed with WFC3/IR on HST and transformed to the JWST photometric system (F200W, Vega). The P-L relations measured are in good agreement, with intercepts (at ) of 25.74 ± 0.04 and 25.72 ± 0.05 for HST and JWST, respectively. Our baseline result comes from the longer-period, higher signal-to-noise ratio Cepheids where we find 25.75 ± 0.05 and 25.75 ± 0.06 mag for HST and JWST, respectively. We find good consistency between this first JWST measurement and HST, and no evidence that HST Cepheid photometry is “biased bright” at the ∼0.2 mag level needed to mitigate the Hubble tension, though comparisons from more SN hosts are warranted and anticipated. We expect future optimized JWST observations to surpass these in quality.

Cluster Cepheids with High Precision Gaia Parallaxes, Low Zero-point Uncertainties, and Hubble Space Telescope Photometry

We present Hubble Space Telescope (HST) photometry of 17 Cepheids in open clusters and their cluster mean parallaxes from Gaia EDR3. These parallaxes are more precise than those from individual Cepheids (G < 8 mag) previously used to measure the Hubble constant because they are derived from an average of >300 stars per cluster. Cluster parallaxes also have smaller systematic uncertainty because their stars lie in the range (G > 13 mag) where the Gaia parallax calibration is the most comprehensive. Cepheid photometry employed in the period–luminosity relation was measured using the same HST instrument (WFC3) and filters (F555W, F814W, F160W) as extragalactic Cepheids in Type Ia supernova hosts. We find no evidence of residual parallax offset in this magnitude range, zp = −3 ± 4 μas, consistent with the results from Lindegren et al. and most studies. The Cepheid luminosity (at P = 10 d and solar metallicity) in the HST near-infrared, Wesenheit magnitude system derived from the cluster sample is mag and −5.890 ± 0.018 mag with or without simultaneous determination of a parallax offset, respectively. These results are similar to measurements from field Cepheids, confirming the accuracy of the Gaia parallaxes over a broad range of magnitudes. The SH0ES distance ladder calibrated only from this sample gives H 0 = 72.9 ± 1.3 and H 0 = 73.3 ± 1.1 km s−1 Mpc−1 with or without offset marginalization; combined with all other anchors we find H 0 = 73.01 ± 0.99 and 73.15 ± 0.97 km s−1 Mpc−1, respectively, a 5% or 7% reduction in the uncertainty in H 0 and a ∼5.3σ Hubble tension relative to Planck+ΛCDM. It appears increasingly difficult to reconcile two of the best-measured cosmic scales, parallaxes from Gaia and the angular size of the acoustic scale of the cosmic microwave background, using the simplest form of ΛCDM to connect the two.

Stellar Populations in type Ia supernova host galaxies at intermediate-high redshift: Star formation and metallicity enrichment histories

ABSTRACT We present a summary of our project that studies galaxies hosting type Ia supernova (SN Ia) at different redshifts. We present Gran Telescopio de Canarias (GTC) optical spectroscopy of six SN Ia host galaxies at redshift z ∼ 0.4–0.5. They are joined to a set of SN Ia host galaxies at intermediate-high redshift, which include galaxies from surveys SDSS and COSMOS. The final sample, after a selection of galaxy spectra in terms of signal-to-noise and other characteristics, consists of 680 galaxies with redshift in the range 0.04 &amp;lt; z &amp;lt; 1. We perform an inverse stellar population synthesis with the code fado to estimate the star formation and enrichment histories of this set of galaxies, simultaneously obtaining their mean stellar age and metallicity and stellar mass. After analysing the correlations among these characteristics, we look for possible dependencies of the Hubble diagram residuals and supernova features (luminosity, colour and strength parameter) on these stellar parameters. We find that the Hubble residuals show a clear dependence on the stellar metallicity weighted by mass with a slope of −0.061 mag dex−1, when represented in logarithmic scale, log 〈ZM/Z⊙〉. This result supports our previous findings obtained from gas oxygen abundances for local and SDSS-survey galaxies. Comparing with other works from the literature that also use the stellar metallicity, we find a similar value, but with more precision and a better significance (2.08 versus ∼ 1.1), due to the higher number of objects and wider range of redshift of our sample.

The Hubble Tension Revisited: Additional Local Distance Ladder Uncertainties

In a recent paper, we investigated possible systematic uncertainties related to the Cepheid color–luminosity calibration method and their influence on the tension between the Hubble constant as inferred from distances to Type Ia supernovae and the cosmic microwave background as measured with the Planck satellite. Here, we study the impact of other sources of uncertainty in the supernova distance ladder, including Cepheid temperature and metallicity variations, supernova magnitudes, and GAIA parallax distances. Using Cepheid data in 19 Type Ia supernova host galaxies from Riess et al., anchor data from Riess et al., and a set of recalibrated Milky Way Cepheid distances, we obtain H 0 = 71.9 ± 2.2 km s−1 Mpc−1, 2.0σ from the Planck value. Excluding Cepheids with estimated color excesses mag to mitigate the impact of the Cepheid color–luminosity calibration, the inferred Hubble constant is H 0 = 68.1 ± 2.6 km s−1 Mpc−1, removing the tension with the Planck value.

Sensitivity of the Hubble Constant Determination to Cepheid Calibration

Motivated by the large observed diversity in the properties of extragalactic extinction by dust, we reanalyze the Cepheid calibration used to infer the Hubble constant, H 0, from Type Ia supernovae, using Cepheid data in 19 Type Ia supernova host galaxies from Riess et al. and anchor data from Riess et al. Unlike the SH0ES team, we do not enforce a fixed universal color–luminosity relation to correct the Cepheid magnitudes. Instead, we focus on a data-driven method, where the optical colors and near-infrared magnitudes of the Cepheids are used to derive individual color–luminosity relations for each Type Ia supernova host and anchor galaxy. We present two different analyses, one based on Wesenheit magnitudes, resulting in H 0 = 73.2 ± 1.3 km s−1 Mpc−1, a 4.2σ tension with the value inferred from the cosmic microwave background. In the second approach, we calibrate an individual extinction law for each galaxy, with noninformative priors using color excesses, yielding H 0 = 73.9 ± 1.8 km s−1 Mpc−1, in 3.4σ tension with the Planck value. Although the two methods yield similar results, in the latter approach, the Hubble constants inferred from the individual Cepheid absolute distance calibrator galaxies range from H 0 = 68.1 ± 3.5 km s−1 Mpc−1 to H 0 = 76.7 ± 2.0 km s−1 Mpc−1. Taking the correlated nature of H 0 inferred from individual anchors into account, and allowing for individual extinction laws, the Milky Way anchor is in 2.1–3.1 σ tension with the NGC 4258 and Large Magellanic Cloud anchors, depending on prior assumptions regarding the color–luminosity relations and the method used for quantifying the tension.