| Autor: |
John C. Raymond, Parviz Ghavamian, Artem Bohdan, Dongsu Ryu, Jacek Niemiec, Lorenzo Sironi, Aaron Tran, Elena Amato, Masahiro Hoshino, Martin Pohl, Takanobu Amano, Frederico Fiuza |
| Jazyk: |
angličtina |
| Rok vydání: |
2023 |
| Předmět: |
|
| Zdroj: |
The Astrophysical Journal, Vol 949, Iss 2, p 50 (2023) |
| Druh dokumentu: |
article |
| ISSN: |
1538-4357 |
| DOI: |
10.3847/1538-4357/acc528 |
| Popis: |
Collisionless shock waves in supernova remnants and the solar wind heat electrons less effectively than they heat ions, as is predicted by kinetic simulations. However, the values of T _e / T _p inferred from the H α profiles of supernova remnant shocks behave differently as a function of Mach number or Alfvén Mach number than what is measured in the solar wind or predicted by simulations. Here we determine T _e / T _p for supernova remnant shocks using H α profiles, shock speeds from proper motions, and electron temperatures from X-ray spectra. We also improve the estimates of sound speed and Alfvén speed used to determine Mach numbers. We find that the H α determinations are robust and that the discrepancies among supernova remnant shocks, solar wind shocks, and computer-simulated shocks remain. We discuss some possible contributing factors, including shock precursors, turbulence, and varying preshock conditions. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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