SN 1987A: Optical Spectrophotometry 130–900 Days After Core Collapse

ABSTRACT Comparison of theoretical line profiles to observations provides important tests for supernova explosion models. We study the shapes of radioactive decay lines predicted by current 3D core-collapse explosion simulations, and compare these to observations of SN 1987A and Cas A. Both the widths and shifts of decay lines vary by several thousand kilometres per second depending on viewing angle. The line profiles can be complex with multiple peaks. By combining observational constraints from 56Co decay lines, 44Ti decay lines, and Fe IR lines, we delineate a picture of the morphology of the explosive burning ashes in SN 1987A. For MZAMS = 15−20 M⊙ progenitors exploding with ∼1.5 × 1051 erg, ejecta structures suitable to reproduce the observations involve a bulk asymmetry of the 56Ni of at least ∼400 km s−1 and a bulk velocity of at least 1500 km s−1. By adding constraints to reproduce the UVOIR bolometric light curve of SN 1987A up to 600 d, an ejecta mass around 14 M⊙ is favoured. We also investigate whether observed decay lines can constrain the neutron star (NS) kick velocity. The model grid provides a constraint VNS > Vredshift, and applying this to SN 1987A gives a NS kick of at least 500 km s−1. For Cas A, our single model provides a satisfactory fit to the NuSTAR observations and reinforces the result that current neutrino-driven core-collapse SN models achieve enough bulk asymmetry in the explosive burning material. Finally, we investigate the internal gamma-ray field and energy deposition, and compare the 3D models to 1D approximations.

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SN 1987A: the Light Curve

Publications of the Astronomical Society of Australia ◽

10.1017/s1323358000025078 ◽

1991 ◽

Vol 9 (1) ◽

pp. 105-106 ◽

Cited By ~ 1

Author(s):

Patricia Whitelock ◽

John Menzies ◽

John A. R. Caldwell

Keyword(s):

Light Curve ◽

Radioactive Decay ◽

Radioactive Isotopes ◽

Core Collapse ◽

Additional Contribution ◽

Decay Energy ◽

Sn 1987A ◽

Total Luminosity ◽

Light Echoes ◽

Γ Ray

AbstractThe changing total luminosity of SN 1987A between 2 and 1200 days after core collapse is illustrated and discussed. From about four weeks after outburst the supernova light curve was dominated by the release of radioactive decay energy; the major contributor being 0.078M⊙ of 56Co. Recently an additional contribution probably from the decay of 57Co and 44Ti appears to be manifesting itself in the light curve. A gradually increasing fraction of the radioactive decay energy has probably been emitted at X- and γ-ray wavelengths; the fluxes are low and no recent measurements have been published. Most of the remaining radioactive decay energy appears to be emitted in the IR and is very difficult to measure. Other factors influencing the interpretation of the recent light curve are the uncertain contribution from long-lived radioactive isotopes and light-echoes. It is therefore premature to make any definitive statements on the contribution from the neutron star, although it is probably less than a few times 1037 erg s−1.

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Blue supergiant progenitors from binary mergers for SN 1987A and other Type II-peculiar supernovae

Proceedings of the International Astronomical Union ◽

10.1017/s1743921317003003 ◽

2016 ◽

Vol 12 (S329) ◽

pp. 64-68

Author(s):

Athira Menon ◽

Alexander Heger

Keyword(s):

Stellar Evolution ◽

Evolutionary Model ◽

Iron Core ◽

Core Collapse ◽

Type Ii ◽

Sn 1987A ◽

Ring Nebula ◽

Binary Mergers ◽

Evolution Study ◽

Different Depths

AbstractWe present results of a systematic and detailed stellar evolution study of binary mergers for blue supergiant (BSG) progenitors of Type II supernovae, particularly for SN 1987A. We are able to reproduce nearly all observational aspects of the progenitor of SN 1987A, Sk –69 °202, such as its position in the HR diagram, the enrichment of helium and nitrogen in the triple-ring nebula and its lifetime before its explosion. We build our evolutionary model based on the merger model of Podsiadlowski et al. (1992), Podsiadlowski et al. (2007) and empirically explore an initial parameter consisting of primary masses, secondary masses and different depths up to which the secondary penetrates the He core during the merger. The evolution of the post-merger star is continued until just before iron-core collapse. Of the 84 pre-supernova models (16 M⊙ − 23 M⊙) computed, the majority of the pre-supernova models are compact, hot BSGs with effective temperature >12 kK and 30 R⊙ − 70 R⊙ of which six match nearly all the observational properties of Sk –69 °202.

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Ultraviolet Observations of SN 1987A

Publications of the Astronomical Society of Australia ◽

10.1017/s1323358000022529 ◽

1988 ◽

Vol 7 (4) ◽

pp. 390-396

Author(s):

N. Panagia

Keyword(s):

Massive Star ◽

Initial Configuration ◽

Core Collapse ◽

Type Ii ◽

Normal Type ◽

Sn 1987A ◽

Photometric Observations ◽

Ultraviolet Observations

AbstractThe IUE observations of SN 1987A are presented and the most important results are briefly summarised. The photometric observations of SN 1987A are discussed in some detail in the context of the supernova energetics. Adding the information from spectroscopy and neutrino observations, it is concluded that SN 1987A is a ‘normal’ Type II explosion (i.e. core collapse of a massive star) with an unusually compact initial configuration, just as expected for the progenitor Sk −69°202.

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The quest for blue supergiants: Evolution of binary merger progenitors of Type-II peculiar supernovae and SN 1987A

Proceedings of the International Astronomical Union ◽

10.1017/s1743921316005846 ◽

2015 ◽

Vol 11 (A29B) ◽

pp. 460-460

Author(s):

Athira Menon ◽

Alexander Heger

Keyword(s):

Stellar Evolution ◽

Effective Temperature ◽

Light Curves ◽

Core Collapse ◽

Type Ii ◽

Sn 1987A ◽

C And N

AbstractWe construct stellar evolution models until core collapse using KEPLER (Woosley & Heger (2007)) to reproduce the observed signatures of the blue supergiant (BSG) progenitor of SN 1987A. This is based on the binary merger scenario proposed by Podsiadlowski (1992) and Ivanova et al. (2002). Various combinations of initial parameters for the binary components (M1=16–18 M⊙ and M2=5–10 M⊙) and their merging, successfully match the He, N/C and N/O ratios, along with the luminosity and effective temperature of the progenitor. Most of our models end their lives as BSGs. Thus we may be able to explain the origin of all Type IIP SNe that resemble SN 1987A through such mergers. We are currently working on the light curves and nuclear yields from the explosion of these models to compare them SN 1987A.

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Measuring the dust content and formation in SN 1987A using detailed radiative transfer modelling

Proceedings of the International Astronomical Union ◽

10.1017/s1743921317004562 ◽

2017 ◽

Vol 12 (S331) ◽

pp. 300-303

Author(s):

Maarten Baes ◽

Peter Camps ◽

Phil J. Cigan ◽

Christopher L. Fryer ◽

Mikako Matsuura ◽

...

Keyword(s):

Spatial Distribution ◽

Radiative Transfer ◽

Observational Constraints ◽

Dust Formation ◽

Core Collapse ◽

Hydrodynamical Models ◽

Sn 1987A ◽

Dust Mass ◽

Transfer Modelling ◽

Cold Dust

AbstractCore-collapse supernovae are expected to be efficient producers of dust, and recent Herschel and ALMA observations have revealed up to 1 M⊙ of cold dust in the inner ejecta of SN 1987A. The formation time scale, spatial distribution and clumpiness, and the importance of the different heating sources of the dust remain poorly understood. We have started a project to make detailed 3D dust radiative transfer models for SN 1987A, based on a combination of the latest observational constraints and input from 3D hydrodynamical models and dust formation models. Preliminary results seem to indicate the need for large, micron-sized dust grains, and a relatively large dust mass.

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Core-Collapse Supernovae as Dust Producers

Proceedings of the International Astronomical Union ◽

10.1017/s1743921308020802 ◽

2007 ◽

Vol 3 (S250) ◽

pp. 437-442

Author(s):

Rubina Kotak

Keyword(s):

Core Collapse ◽

Spitzer Space Telescope ◽

Mid Infrared ◽

Space Telescope ◽

Sn 1987A ◽

Ir Studies ◽

Low Mass ◽

Very High

AbstractAlthough it has long been hypothesised that core-collapse supernovae may produce large quantities of dust, interest in this problem has recently been rekindled given the enormous dust masses inferred at very high redshifts (z ≳ 6), when conventional low-mass dust-producing stars would fail to contribute significantly to the universal dust budget. Emission due to warm dust peaks at mid-IR wavelengths. However, with the notable exception of SN 1987A, supernova studies in the mid-IR have been virtually non-existent until the advent of the Spitzer Space Telescope. On behalf of the Mid-Infrared Supernova Consortium, I briefly discuss recent exciting results from mid-IR studies of core-collapse supernovae using Spitzer and attempt to put the role of supernovae as major dust producers into perspective.

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Aspherical supernova explosions

Symposium - International Astronomical Union ◽

10.1017/s0074180900212473 ◽

2003 ◽

Vol 212 ◽

pp. 387-394 ◽

Cited By ~ 3

Author(s):

Peter A. Höflich ◽

Dietrich Baade ◽

Alexei M. Khokhlov ◽

Lifan Wang ◽

J. Craig Wheeler

Keyword(s):

Axial Symmetry ◽

Radiation Transport ◽

Core Collapse ◽

Intermediate Mass ◽

Low Velocity ◽

Transport Models ◽

Sn 1987A ◽

Direct Observations ◽

Supernova Explosions ◽

New Evidence

Core collapse supernovae (SN) are the final stages of stellar evolution in massive stars during which the central region collapses, forms a neutron star (NS), and the outer layers are ejected. Recent explosion scenarios assumed that the ejection is due to energy deposition by neutrinos into the envelope, but detailed models do not produce powerful explosions. There is new and mounting evidence for an asphericity and, in particular, for axial symmetry in several supernovae which may be hard to reconcile within the spherical picture. This evidence includes the observed high polarization and its variation with time, pulsar kicks, high velocity iron-group and intermediate-mass elements material observed in remnants, direct observations of the debris of SN 1987A, etc. Some of the new evidence is discussed in more detail. To be in agreement with the observations, any successful mechanism must invoke some sort of axial symmetry for the explosion. We consider jet-induced/dominated explosions of core collapse supernovae. Our study is based on detailed 3-d hydrodynamical and radiation transport models. We find that the observations can be explained by low velocity, massive jets which stall well within the SN envelope. Such outflows may be produced by MHD-mechanisms, convective dominated accretion disks on the central object or asymmetric neutrino emissions. Asymmetric density/chemical distributions and, for SN 2002ap, off-center energy depositions have been identified as crucial for the interpretation of the polarization.

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Core-Collapse Supernova Simulations including Neutrino Interactions from the Virial EOS

Proceedings of the International Astronomical Union ◽

10.1017/s1743921317004586 ◽

2017 ◽

Vol 12 (S331) ◽

pp. 107-112 ◽

Cited By ~ 4

Author(s):

Evan O’Connor ◽

C. J. Horowitz ◽

Zidu Lin ◽

Sean Couch

Keyword(s):

Neutral Current ◽

Radiation Hydrodynamics ◽

Core Collapse ◽

Core Collapse Supernova ◽

Sn 1987A ◽

Interaction Terms ◽

Central Engine ◽

Matter Interaction ◽

Supernova Explosions ◽

Protoneutron Star

AbstractCore-collapse supernova explosions are driven by a central engine that converts a small fraction of the gravitational binding energy released during core collapse to outgoing kinetic energy. The suspected mode for this energy conversion is the neutrino mechanism, where a fraction of the neutrinos emitted from the newly formed protoneutron star are absorbed by and heat the matter behind the supernova shock. Accurate neutrino-matter interaction terms are crucial for simulating these explosions. In this proceedings for IAUS 331, SN 1987A, 30 years later, we explore several corrections to the neutrino-nucleon scattering opacity and demonstrate the effect on the dynamics of the core-collapse supernova central engine via two dimensional neutrino-radiation-hydrodynamics simulations. Our results reveal that the explosion properties are sensitive to corrections to the neutral-current scattering cross section at the 10-20% level, but only for densities at or above ~1012 g cm−3.

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Mass of dust in core-collapse supernovae as viewed from energy balance in the ejecta

Proceedings of the International Astronomical Union ◽

10.1017/s1743921317001582 ◽

2016 ◽

Vol 12 (S329) ◽

pp. 431-431

Author(s):

Takaya Nozawa

Keyword(s):

Energy Balance ◽

Far Infrared ◽

Core Collapse ◽

Mid Infrared ◽

Cassiopeia A ◽

Sn 1987A ◽

Formation History ◽

History Of ◽

The Masses ◽

Small Dust

AbstractRecent far-infrared (FIR) observations have revealed the presence of freshly formed dust with the masses exceeding 0.1 M⊙ in young remnants of core-collapse supernovae (CCSNe) such as SN 1987A and Cassiopeia A. Meanwhile, dust masses derived from near- to mid-infrared (N/MIR) observations of CCSNe a few years after explosions are on the order of 10−5–10−3M⊙. Here, we demonstrate that such small dust masses as seen from N/MIR observations would not necessarily reflect the formation history of dust but could be just limited by the luminosity of the SN that can heat up dust formed in the ejecta.

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