Supernovae at distances <40 Mpc

II. Supernova rate in the local Universe

¹ Department of Physics, Tsinghua University, Haidian District, Beijing 100084, China
² Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210023, China
³ Las Cumbres Observatory, 6740 Cortona Drive Suite 102, Goleta, CA 93117-5575, USA
⁴ Department of Physics, University of California, Santa Barbara, CA 93106-9530, USA
⁵ Yunnan Observatories, Chinese Academy of Sciences, Kunming 650216, China
⁶ International Centre of Supernovae, Yunnan Key Laboratory, Kunming 650216, PR China
⁷ School of Physics and Astronomy, Tel Aviv University, Tel Aviv 69978, Israel
⁸ Center for Astrophysics | Harvard & Smithsonian, 60 Garden Street, Cambridge, MA 02138-1516, USA
⁹ The NSF AI Institute for Artificial Intelligence and Fundamental Interactions, USA
¹⁰ School of Physics and Information Engineering, Jiangsu Second Normal University, Nanjing 211200, China
¹¹ Beijing Planetarium, Beijing Academy of Sciences and Technology, Beijing, 100044, China

^★ Corresponding author: wang_xf@mail.tsinghua.edu.cn

Received: 21 October 2024
Accepted: 2 April 2025

Abstract

Context. This is the second paper of a series aiming to determine the birth rates of supernovae (SNe) in the local Universe.

Aims. We aimed to estimate the SN rates in the local Universe and fit the delay-time distribution of type Ia SNe (SNe Ia) to put constraints on their progenitor scenarios.

Methods. We performed a Monte Carlo simulation to estimate volumetric rates using the nearby SN sample introduced in Paper I. The rate evolution of core-collapse (CC) SNe closely follows the evolution of the cosmic star formation history, while the rate evolution of SNe Ia involves the convolution of the cosmic star formation history and a two-component delay-time distribution including a power law and a Gaussian component.

Results. The volumetric rates of type Ia, Ibc, and II SNe are derived as 0.325 ± 0.040_−0.010^+0.016, 0.160 ± 0.028_−0.014^+0.044, and 0.528 ± 0.051_−0.013^+0.162 (in units of 10⁻⁴yr⁻¹ Mpc⁻³ h₇₀³), respectively. The rate of CCSNe (0.688 ± 0.078_−0.027^+0.0206) is consistent with previous estimates, which trace the star formation history. Conversely, the newly derived local SN Ia rate is larger than existing results given at redshifts 0.01 < z < 0.1, favoring an increased rate from the Universe at z ∼ 0.1 to the local Universe at z < 0.01. A two-component model effectively reproduces the rate variation, with the power law component accounting for the rate evolution at larger redshifts and the Gaussian component with a delay time of 12.63 ± 0.38 Gyr accounting for the local rate evolution. This delayed component, with its exceptionally long delay time, suggests that the progenitors of these SNe Ia were formed around 1 Gyr after the birth of the Universe, which could only be explained by a double-degenerate progenitor scenario. Comparison with the Palomar Transient Factory (PTF) sample of SNe Ia at z = 0.073 and the morphology of their host galaxies, reveals that the increased SN Ia rate at z < 0.01 is primarily due to the SNe Ia of massive E and S0 galaxies with old stellar populations. Based on the above results, we estimate the Galactic SN rate as 3.08 ± 1.29 per century.