Urychlování částic a zesílení magnetického pole v koncových rázových vlnách AGN jetů
| Název práce v češtině: | Urychlování částic a zesílení magnetického pole v koncových rázových vlnách AGN jetů |
|---|---|
| Název v anglickém jazyce: | Particle acceleration and magnetic-field amplification in the termination shocks of AGN jets |
| Klíčová slova: | aktivní galaktická jádra|astrofyzikální jety|urychlování částic v rázových vlnách|magnetická pole |
| Klíčová slova anglicky: | active galactic nuclei|astrophysical jets|particle acceleration in shocks|magnetic fields |
| Akademický rok vypsání: | 2020/2021 |
| Typ práce: | diplomová práce |
| Jazyk práce: | čeština |
| Ústav: | Ústav teoretické fyziky (32-UTF) |
| Vedoucí / školitel: | Anabella Teresa Araudo, Dr. |
| Řešitel: | skrytý - zadáno a potvrzeno stud. odd. |
| Datum přihlášení: | 23.01.2021 |
| Datum zadání: | 25.01.2021 |
| Datum potvrzení stud. oddělením: | 23.03.2021 |
| Datum a čas obhajoby: | 09.09.2021 10:00 |
| Datum odevzdání elektronické podoby: | 10.08.2021 |
| Datum odevzdání tištěné podoby: | 10.08.2021 |
| Datum proběhlé obhajoby: | 09.09.2021 |
| Oponenti: | Diego Nicolas Calderón Espinoza, Ph.D. |
| Zásady pro vypracování |
| The objective of this project is to investigate particle acceleration and magnetic field amplification in the termination shocks of AGN jets. In particular, to apply the new picture presented by Araudo et al. (2016, 2018) to the radiogalaxies 3C105, 3C 227, and 3C445 for which well resolved and multi-wavelength data are available (Orienti et al. 2012, 2017, 2020). To carry out this study the student will use recent developments in the field to obtain new theoretical results to be confronted against observational data. What we plan to do is:
1) Determination of the magnetic field and energy density in non thermal particles by using the radio and X-ray emission. 2) Simple study of plasma microphysics by considering the high-energy cutoff of the synchrotron spectrum. By carrying out this study, the student will learn basic plasma astrophysics, multi-wavelength data modelling, and numerical tools to perform semi analytic calculations. The results of this study will be published in a specialized journal. |
| Seznam odborné literatury |
| [1] Araudo A., Bell A.R., Crilly A., Blundell K. 2016, MNRAS 460, 3554
[2] Araudo A., Bell A.R., Blundell K., Matthews J. 2018, MNRAS 473, 3500 [3] Bell A. R. 1978, MNRAS 182, 147 [4] Bell A. R. 2004, MNRAS 353, 550 [5] Orienti M., Prieto M. A., Brunetti G., Mack K.-H., Massaro F., Harris D. E. 2012, MNRAS 419, 2338 [6] Orienti M., Brunetti G., Nagai H., Paladino R., Mack K., Prieto M. A. 2017, MNRAS 469, L123 [7] Orienti M., Migliori G., Brunetti G., et al. 2020, MNRAS 494, 2244 |
| Předběžná náplň práce v anglickém jazyce |
| One of the most exciting and unsolved problems in Astrophysics is figuring out the origin of the Ultra High Energy Cosmic Rays (UHECRs). These are particles have an energy of ∼100 EeV1 and arrive on the Earth from outside the Galaxy, but their origin remains unknown. Active Galactic Nuclei (AGN) have been proposed as sources of UHECRs. AGN host a super-massive black hole at their centre, surrounded by an accretion disc of matter from where bipolar relativistic jets are launched. Radiogalaxies are the subclass of AGN where jets are detected at radio frequencies. Jets moving in the intergalactic medium produce shock waves where particles can be accelerated via Diffusive Shock Acceleration (DSA).
Diffusive shock acceleration (Bell 1978) is the most established mechanism to accelerate particles in astrophysical sources where shock waves are present. Particles diffuse back and forth across the shock front and gain energy in each crossing. Therefore, long times are required to accelerate the most energetic cosmic rays unless the magnetic field around the shock is amplified. The amplified turbulent field scatters particles rapidly so that they cross the shock more frequently achieving a higher energy in the available time. Non Resonant Hybrid instabilities (Bell 2004) produced by the streaming of cosmic rays are fast enough to amplify the magnetic field by orders of magnitude. |