Sample interview questions: Can you explain the concept of cosmic rays and their impact on astrophysical processes?
Sample answer:
Cosmic rays are high energy particles that originate from beyond the Earth’s atmosphere. They are composed of protons (91%), alpha particles (8%), and heavier atomic nuclei (1%). These particles are accelerated to extremely high energies, reaching up to 10^20 electron volts (eV) or even higher.
Cosmic rays interact with the interstellar medium, producing secondary particles such as pions, kaons, and muons. These interactions can also produce gamma rays, X-rays, and radio waves, which are important probes for studying the composition and properties of the interstellar medium.
Cosmic rays have a significant impact on various astrophysical processes:
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Star Formation: Cosmic rays can trigger the formation of new stars by compressing interstellar gas clouds, leading to gravitational collapse and the birth of new stars.
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Supernova Remnants: Cosmic rays are accelerated by shock waves in supernova remnants, reaching energies well above those attainable in particle accelerators on Earth. These energetic particles can interact with the surrounding interstellar medium, producing gamma rays, X-rays, and radio waves, which provide valuable insights into the physics of supernova remnants.
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Interstellar Turbulence: Cosmic ray… Read full answer