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Disputation: Rebecca Anne Robinson

Doctoral candidate Rebecca Anne Robinson at the Institute of Theoretical Astrophysics, Faculty of Mathematics and Natural Sciences, is defending the thesis "Magnetic characteristics of quiet Sun nanoflares" for the degree of Philosophiae Doctor.

Portrait photo of a young, smiling woman
Rebecca Robinson, PhD, UiO.

Join the disputation

The PhD defence and trial lecture will be 100% in-person. The room opens for participation just before the disputation starts, and closes for new participants approximately 15 minutes after the defence has begun.

Join the trial lecture - 21st of September at 10:15 (Aud. 209, Svein Rosselands Hus)

"Where do elements heavier than iron come from?" 

Conferral summary

Nanobluss er energirike, men relativt småe bluss på sola som fører til høye temperaturer i solas atmosfære. I dette arbeidet ble det brukt en simulering for å finne ut hvordan nanobluss er bygget opp, hvordan de kan bidra til de høye atmosfæriske temperaturene og hvordan de kan observeres. Nanoblusset vårt ble simulert ved et uhell, men dette førte til mange spennende funn!

"We accidentally simulated an explosion on the Sun"

 After centuries of scientific research on the Sun, we have come to the following monumental conclusion: 

We don not know why the Sun is so hot.

This might seem ridiculous at first glance. Of course the Sun is hot; it’s a nuclear fusion machine! Indeed, the Sun’s core measures in at about 10 million degrees, but the temperature plummets to a meager 5,000 degrees at the solar surface. But then, something strange happens; the temperature of the solar atmosphere soars to millions of degrees again.

How can this be?

Where there is a jump in temperature, there must be another energy source. As it turns out, the Sun generates its magnetic field just beneath its surface, and magnetic fields carry a lot of energy — especially when field lines reconnect with one another. 

My work focuses on magnetic reconnection as a source of atmospheric energy that can ultimately power nanoflares, or tiny solar explosions. Using our self-consistent simulation, we accidentally modelled a nanoflare that is a direct result of the coalescence and reconnection of magnetic fields. We demonstrate exactly how this happens, how the nanoflare contributes to atmospheric heating, and how it could be observed with current and future telescopes.

Simulated nanoflare as evidenced by hot plasma (yellow) and multiple reconnecting magnetic features (orange, red, cyan, and green lines). This rendering was made using VAPOR.
Image: Simulated nanoflare as evidenced by hot plasma (yellow) and multiple reconnecting magnetic features (orange, red, cyan, and green lines). This rendering was made using VAPOR.

Contact information for the Institute of Theoretical Astrophysics

Tags: PhD defense, disputas, Solar Physics
Published Sep. 7, 2023 10:00 AM - Last modified Jan. 8, 2024 3:51 PM