Related papers: Ionization freeze-out and barium problem in supern…
We have developed a time-dependent model of ionization, excitation and energy balance of SN 1987A atmosphere at the photospheric epoch to study early behavior of hydrogen and helium lines. The ionization freeze-out effects play a key role…
We study a time-dependent hydrogen ionization in the atmosphere of SN 1987A during the first month after the explosion. The model includes kinetics of hydrogen ionization and excitation, molecular hydrogen kinetics, and a time-dependent…
The temperature and ionization of SN 1987A is modeled between 200 and 2000 days in its nebular phase, using a time-dependent model. We include all important elements, as well as the primary composition zones in the supernova. The energy…
Supernova (SN) 1987A, with its long-rising ($\gtrsim$40 days) light curve, defines a rare subclass of type II SNe known as 1987A-like events. Representing only 1-3 percent of all core-collapse SNe and often found in low-metallicity…
We investigate a simplified kinetic system of the hydrogen atom (two levels plus continuum) under conditions of a type IIP supernova at the plateau phase that realistically describes the basic properties of the complete system. We have…
The rings observed around supernova remnant 1987A are emitted by a plasma mainly made of ionized and neutral hydrogen atoms. With a density of 10 power 10 atoms per cubic metre, and at least a dimension of plasma of 0.01 light-year, the…
We propose a model kinetic system of the hydrogen atom (two levels plus continuum) under the conditions typical for atmospheres of Type IIP supernovae in the plateau stage. Despite the simplicity of this system, it describes realistically…
Using the temperature and ionization calculated in our previous paper, we model the spectral evolution of SN 1987A. The IR-catastrophe is seen in the metal lines as a transition from thermal to non-thermal excitation, most clearly in the [O…
Ten years of photometric observations of SN 1987A are reviewed. The optical and near-infrared colors are now declining at less than 1 magnitude per 1000 days, which is consistent with both the infrared ``freeze-out'' and the possible energy…
The importance of allowance for the time-dependent effect in the kinetics at the photospheric phase during a supernova explosion has been confirmed by several independent research groups. The time-dependent effect provides a higher degree…
Both CO and SiO have been observed at early and late phases in SN 1987A. H_2 was predicted to form at roughly the same time as these molecules, but was not detected at early epochs. Here we report the detection of NIR lines from H_2 at 2.12…
We present near-infrared spectroscopic observations of SN 1987A covering the period 1358 to 3158 days post-explosion. This is the first time that IR spectra of a supernova have been obtained to such late epochs. The spectra comprise…
We use low-dispersion spectra obtained at the Magellan Observatory to study the broad H-alpha emission from the reverse shock of the infant supernova remnant SNR1987A. These spectra demonstrate that the spatio-kinematic structure of the…
We have used the Faint Object Spectrograph on the Hubble Space Telescope to observe the spectra of SN 1987A over the wavelength range 2000 -- 8000\ \AA\ on dates 1862 and 2210 days after the supernova outburst. Even these pre-COSTAR…
The H II region created by the progenitor of SN 1987A was further heated and ionized by the supernova flash. Prior to the flash, the temperature of the gas was 4000 - 5000 K, and helium was neutral, while the post-flash temperature was only…
Shock breakout is the first electromagnetic signal from supernovae (SNe), which contains important information on the explosion energy and the size and chemical composition of the progenitor star. This paper presents the first…
The presence of narrow high-temperature emission lines from nitrogen-rich gas close to SN 1987A has been the principal observational constraint on the evolu- tionary status of the supernova's progenitor. A new analysis of the complete…
Observations with the Hubble Space Telescope (HST), conducted since 1990, now offer an unprecedented glimpse into fast astrophysical shocks in the young remnant of supernova 1987A. Comparing observations taken in 2010 using the refurbished…
At a distance of 50 kpc, Supernova 1987A is an ideal target to study how a young supernova (SN) evolves in time. Its equatorial ring, filled with material expelled from the progenitor star about 20,000 years ago, has been engulfed with SN…
Majoron-like bosons would emerge from a supernova (SN) core by neutrino coalescence of the form $\nu\nu\to\phi$ and $\bar\nu\bar\nu\to\phi$ with 100 MeV-range energies. Subsequent decays to (anti)neutrinos of all flavors provide a flux…