Curated by RSF Research Staff
UV emission linked to Supernova explosion mechanism
Supernovae are an explosion of a massive supergiant star which may shine with the brightness of 10 billion suns! The study of these phenomena has unlocked mysteries about black holes, the origin of metals such as gold and the dynamic of the universe. Supernovae are rare -- the last supernova seen in our galaxy was recorded in 1604, according to NASA. However, the Universe is large and astronomers estimated that one of the Milky Way's massive stars explodes about every 50 years on average .
By observing these supernovas in other galaxies, astronomers now understand that a supernova is the explosion of a massive star revealing a black hole at the center of it. Further observations confirmed this idea. In 2006, Alex Filippenko and his team observed an unusual supernova 440 million light years away . As it exploded, the supernova released an intense flash of X-rays called a gamma-ray burst. These bursts formed from spiraling matter falling into black holes confirmed the presence of the black hole.
Moreover, research done on supernovas are used to study the entire universe. For example, a subtype of supernovas, Type Ia (the thermonuclear ones, see classification), are among the brightest things in the universe, and all shine with roughly equal intensity. So by observing supernovas over time, researchers in the 1990s were able to see that the supernovas were all moving away from the center of the universe at an increasing rate, showing the movement of the universe and helping us to understand its dynamic. Therefore, astronomers are still today looking carefully at supernovae.
"The current study makes one more step to the understanding of the physics of superluminous supernova and helps to identify the scenario of the explosion."
Alexey Tolstov - The University of Tokyo Institutes for Advanced Study, Japan
On August 3, 2017, new progress were published by an international team of researchers lead by Alexey Tolstov . They discovered an extremely luminous ultraviolet emission among superluminous supernovae (SLSNe). Using radiation hydrodynamics simulations, they compared the experimental data with the most popular SLSN models: pair-instability supernova, magnetar, and interaction with circumstellar medium. Doing so they were able to conclude that differences in late-time UV emission and in color evolution found between the models can be used to link an observed SLSN event to the most appropriate model. The next step in their research will be to apply simulations on other SLSNe, and make more realistic models.
Continue reading at: https://phys.org/news/2017-09-ultraviolet-superluminous-supernova-key-revealing.html http://www.skyandtelescope.com/astronomy-news/milky-way-supernova-rate-confirmed/ http://www.berkeley.edu/news/media/releases/2006/08/30_xray.shtml http://iopscience.iop.org/article/10.3847/2041-8213/aa808e/meta