Diversity of dust properties in external galaxies confirmed by polarization signals from Type II supernovae
arXiv:2211.11421 · doi:10.3847/2041-8213/aca47d
Abstract
Investigating interstellar (IS) dust properties in external galaxies is important not only to infer the intrinsic properties of astronomical objects but also to understand the star/planet formation in the galaxies. From the non-Milky-Way-like extinction and interstellar polarization (ISP) observed in reddened Type Ia supernovae (SNe), it has been suggested that their host galaxies contain dust grains whose properties are substantially different from the Milky-Way (MW) dust. It is important to investigate the universality of such non-MW-like dust in the universe. Here we report spectropolarimetry of two highly-extinguished Type II SNe (SN 2022aau and SN 2022ame). SN 2022aau shows a polarization maximum at a shorter wavelength than MW stars, which is also observed in some Type Ia SNe. This is clear evidence for the existence of non-MW-like dust in its host galaxy (i.e., NGC 1672). This fact implies that such non-MW-like dust might be more common in some environments than expected, and thus it might affect the picture of the star/planet formation. On the other hand, SN 2022ame shows MW-like ISP, implying the presence of MW-like dust in its host galaxy (i.e., NGC 1255). Our findings confirm that dust properties of galaxies are diverse, either locally or globally. The present work demonstrates that further investigation of IS dust properties in external galaxies using polarimetry of highly-reddened SNe is promising, providing a great opportunity to study the universality of such non-MW-like dust grains in the universe.
11 pages, 5 figures, accepted for publication in ApJ Letters
References in corpus (16)
- Improved Cosmological Constraints from New, Old and Combined Supernova Datasets
- An Analysis of the Shapes of Interstellar Extinction Curves. V. The IR-Through-UV Curve Morphology
- Spectropolarimetry of Supernovae
- The Carnegie Supernova Project: Intrinsic Colors of Type Ia Supernovae
- Optical and Near-Infrared Observations of the Highly Reddened, Rapidly Expanding Type Ia Supernova 2006X in M100
- Type II supernova spectral diversity I: Observations, sample characterization and spectral line evolution
- Anomalous extinction behaviour towards the Type Ia SN 2003cg
- The colour-lightcurve shape relation of Type Ia supernovae and the reddening law
- Spectropolarimetry of the Type Ib/c SN 2005bf
- A search for HI absorption in nearby radio galaxies using HIPASS
- SN 2002cv: A Heavily Obscured Type Ia Supernova
- Properties of extragalactic dust inferred from linear polarimetry of Type Ia Supernovae
- Evidence for multiple origins of fast declining Type II supernovae from spectropolarimetry of SN 2013ej and SN 2017ahn
- Magnetic fields and cosmic rays in M 31. I. Spectral indices, scale lengths, Faraday rotation, and magnetic field pattern
- Continuum Foreground Polarization and Na~I Absorption in Type Ia SNe
- Circumstellar Light Echo as a Possible Origin of the Polarization of Type IIP Supernovae