تقرير
Relative intrinsic scatter in hierarchical Type Ia supernova siblings analyses: Application to SNe 2021hpr, 1997bq & 2008fv in NGC 3147
| العنوان: | Relative intrinsic scatter in hierarchical Type Ia supernova siblings analyses: Application to SNe 2021hpr, 1997bq & 2008fv in NGC 3147 |
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| المؤلفون: | Ward, Sam M., Thorp, Stephen, Mandel, Kaisey S., Dhawan, Suhail, Jones, David O., Taggart, Kirsty, Foley, Ryan J., Narayan, Gautham, Chambers, Kenneth C., Coulter, David A., Davis, Kyle W., de Boer, Thomas, de Soto, Kaylee, Earl, Nicholas, Gagliano, Alex, Gao, Hua, Hjorth, Jens, Huber, Mark E., Izzo, Luca, Langeroodi, Danial, Magnier, Eugene A., McGill, Peter, Rest, Armin, Rojas-Bravo, César, Wojtak, Radosław |
| سنة النشر: | 2022 |
| المجموعة: | Astrophysics |
| مصطلحات موضوعية: | Astrophysics - Cosmology and Nongalactic Astrophysics, Astrophysics - Astrophysics of Galaxies, Astrophysics - High Energy Astrophysical Phenomena |
| الوصف: | We present Young Supernova Experiment $grizy$ photometry of SN 2021hpr, the third Type Ia supernova sibling to explode in the Cepheid calibrator galaxy, NGC 3147. Siblings are useful for improving SN-host distance estimates, and investigating the contributions towards the SN Ia intrinsic scatter (post-standardisation residual scatter in distance estimates). We thus develop a principled Bayesian framework for analyzing SN Ia siblings. At its core is the cosmology-independent relative intrinsic scatter parameter, $\sigma_{Rel}$: the dispersion of siblings distance estimates relative to one another within a galaxy. It quantifies the contribution towards the total intrinsic scatter, $\sigma_0$, from within-galaxy variations about the siblings' common properties. It also affects the combined-distance uncertainty. We present analytic formulae for computing a $\sigma_{Rel}$-posterior from individual siblings distances (estimated using any SN-model). Applying a newly trained BayeSN model, we fit the light curves of each sibling in NGC 3147 individually, to yield consistent distance estimates. However, the wide $\sigma_{Rel}$-posterior means $\sigma_{Rel}\approx\sigma_0$ is not ruled out. We thus combine the distances by marginalizing over $\sigma_{Rel}$ with an informative prior: $\sigma_{Rel}\sim U(0,\sigma_0)$. Simultaneously fitting the trio's light curves improves constraints on distance, and each sibling's individual dust parameters, compared to individual fits. Higher correlation also tightens dust parameter constraints. Therefore, $\sigma_{Rel}$-marginalization yields robust estimates of siblings distances for cosmology, and dust parameters for siblings-host correlation studies. Incorporating NGC 3147's Cepheid-distance yields $H_0=78.4\pm 6.5\,$km/s/Mpc. Our work motivates analyses of homogeneous siblings samples, to constrain $\sigma_{Rel}$, and its SN-model dependence. Comment: Accepted for publication in ApJ. 22 pages, 11 figures, 8 tables. Single-galaxy siblings analysis |
| نوع الوثيقة: | Working Paper |
| الوصول الحر: | http://arxiv.org/abs/2209.10558Test |
| رقم الانضمام: | edsarx.2209.10558 |
| قاعدة البيانات: | arXiv |
| الوصف غير متاح. |