Cococubed.com SN 1987A Light Curve
Home Astronomy research   Software Infrastructure:      MESA      FLASH-X      STARLIB      MESA-Web      starkiller-astro      My instruments   White dwarf supernova:      Stable nickel production      Remnant metallicities      Colliding white dwarfs      Merging white dwarfs      Ignition conditions      Metallicity effects      Central density effects      Detonation density effects      Tracer particle burning      Subsonic burning fronts      Supersonic burning fronts      W7 profiles   Massive star supernova:      Rotating progenitors      3D evolution      26Al & 60Fe      44Ti, 60Co & 56Ni      Yields of radionuclides      Effects of 12C +12C      SN 1987A light curve      Constraints on Ni/Fe ratios      An r-process   Neutron Stars and Black Holes:      Black Hole mass spectrum      Compact object IMF      He burn on neutron stars   Stars:      Variable white dwarfs      Pop III with JWST      Micronovae      Neutrino HR diagram      Monte Carlo massive stars      Pre-supernova neutrinos      Pre-supernova variations      Monte Carlo white dwarfs      SAGB stars      Nugrid Yields I      Classical novae      He shell convection      Presolar grains      BBFH at 40 years   Chemical Evolution:      Iron Pseudocarbynes      Radionuclides in the 2020s      Hypatia catalog      Zone models H to Zn      Mixing ejecta      γ-rays within 100 Mpc   Thermodynamics & Networks      Stellar EOS      12C(α,γ)16O Rate      Proton-rich NSE      Reaction networks      Bayesian reaction rates   Verification Problems:      Validating an astro code      Su-Olson      Cog8      Mader      RMTV      Sedov      Noh Software instruments Presentations Illustrations cococubed YouTube Bicycle adventures Public Outreach Education materials 2022 ASU Solar Systems Astronomy 2022 ASU Energy in Everyday Life AAS Journals AAS YouTube 2022 Earendel, A Highly Magnified Star 2022 TV Columbae, Micronova 2022 White Dwarfs and 12C(α,γ)16O 2022 MESA VI 2022 MESA in Don't Look Up 2022 MESA Marketplace 2012-2023 MESA Schools 2022 MESA Classroom 2021 Bill Paxton, Tinsley Prize Contact: F.X.Timmes my one page vitae, full vitae, research statement, and teaching statement.	The light curve of SN 1987A revisited: constraining production masses of radioactive nuclides (2014) In this article, we revisit the evidence for the contribution of the long-lived radioactive nuclides $^{44}$Ti, $^{55}$Fe, $^{56}$Co, $^{57}$Co, and $^{60}$Co to the UVOIR light curve of SN 1987A. We show that the V-band luminosity constitutes a roughly constant fraction of the bolometric luminosity between 900 and 1900 days, and we obtain an approximate bolometric light curve out to 4334 days by scaling the late time V-band data by a constant factor where no bolometric light curve data is available. Considering the five most relevant decay chains starting at $^{44}$Ti, $^{55}$Co, $^{56}$Ni, $^{57}$Ni, and $^{60}$Co, we perform a least squares fit to the constructed composite bolometric light curve. For the nickel isotopes, we obtain best fit values of M($^{56}$Ni) = (7.1 $\pm$ 0.3) × 102 M⊙ and M($^{57}$Ni) = (4.1 $\pm$ 1.8) × 10-3 M⊙. Our best fit $^{44}$Ti mass is M($^{44}$Ti) = (0.55 $\pm$ 0.17) × 10-4 M⊙. which is in disagreement with the much higher (3.1 $\pm$ 0.8) × 10-4 M⊙ recently derived from INTEGRAL observations. The half-lives of $^{60}$Co and $^{55}$Fe are quite similar, which introduces a degeneracy for the fitting algorithm. As a result, we can only give upper limits on the relevant production masses of M($^{55}$Co) < 7.2 × 10-3 M⊙ and M($^{60}$Co) < 1.7 × 10-4 M⊙. Furthermore, we find that the leptonic channels in the decay of $^{57}$Co (internal conversion and Auger electrons) are a significant contribution and constitute up to 15.5% of the total luminosity. Consideration of the kinetic energy of these electrons is essential in lowering our best fit nickel isotope production ratio to [$^{57}$Ni / $^{56}$Ni] = 2.5$\pm$1.1 which is still somewhat high but in agreement with gamma-ray observations and model predictions. [57Ni / 56Ni] after freeze-out For canonically accepted values Including freeze-out corrections Importance of 57Co Best fit