Measuring the Hubble constant with Type Ia supernovae as near-infrared standard candles

作者：Dhawan Suhail; Jha Saurabh W; Leibundgut Bruno

来源：Astronomy & Astrophysics, 2018, 609: A72.

DOI：10.1051/0004-6361/201731501

<jats:p>The most precise local measurements of <jats:italic>H</jats:italic><jats:sub>0</jats:sub> rely on observations of Type Ia supernovae (SNe Ia) coupled with Cepheid distances to SN Ia host galaxies. Recent results have shown tension comparing <jats:italic>H</jats:italic><jats:sub>0</jats:sub> to the value inferred from CMB observations assuming ΛCDM, making it important to check for potential systematic uncertainties in either approach. To date, precise local <jats:italic>H</jats:italic><jats:sub>0</jats:sub> measurements have used SN Ia distances based on optical photometry, with corrections for light curve shape and colour. Here, we analyse SNe Ia as standard candles in the near-infrared (NIR), where luminosity variations in the supernovae and extinction by dust are both reduced relative to the optical. From a combined fit to 9 nearby calibrator SNe with host Cepheid distances from Riess et al. (2016) and 27 SNe in the <jats:italic>Hubble </jats:italic>flow, we estimate the absolute peak <jats:italic>J</jats:italic> magnitude <jats:italic>M</jats:italic><jats:sub><jats:italic>J</jats:italic></jats:sub> = −18.524 ± 0.041 mag and <jats:italic>H</jats:italic><jats:sub>0</jats:sub> = 72.8 ± 1.6 (statistical) ±2.7 (systematic) km s<jats:sup>-1</jats:sup> Mpc<jats:sup>-1</jats:sup>. The 2.2% statistical uncertainty demonstrates that the NIR provides a compelling avenue to measuring SN Ia distances, and for our sample the intrinsic (unmodeled) peak <jats:italic>J</jats:italic> magnitude scatter is just ~0.10 mag, even without light curve shape or colour corrections. Our results do not vary significantly with different sample selection criteria, though photometric calibration in the NIR may be a dominant systematic uncertainty. Our findings suggest that tension in the competing <jats:italic>H</jats:italic><jats:sub>0</jats:sub> distance ladders is likely not a result of supernova systematics that could be expected to vary between optical and NIR wavelengths, like dust extinction. We anticipate further improvements in <jats:italic>H</jats:italic><jats:sub>0</jats:sub> with a larger calibrator sample of SNe Ia with Cepheid distances, more <jats:italic>Hubble </jats:italic>flow SNe Ia with NIR light curves, and better use of the full NIR photometric data set beyond simply the peak <jats:italic>J</jats:italic>-band magnitude. </jats:p>

• 出版日期2018-1-9