Essays about: "photosphere"

Showing result 1 - 5 of 8 essays containing the word photosphere.

1. 1. Fitting a photospheric prompt emission model to GRB data: The Kompaneets RMS approximation (KRA)

   University essay from KTH/Fysik

   Author : Oscar Wistemar; [2023]
   Keywords : Gamma-Ray Bursts; Astrophysics; Engineering Physics; Gamma-Blixtar; Astrofysik; Teknisk Fysik;

   Abstract : Gamma-ray bursts (GRBs) are some of the most energetic events in the universe. Shocks occurring below the photosphere are likely radiation mediated shocks (RMSs) and are suspected to shape the spectra. Due to computational costs of simulating RMSs, models had not been fitted to data and a faster model was needed. READ MORE

3. 2. Prompt emission in Gamma-ray bursts; Photospheric Radiation from Synchrotron-Like spectra

   University essay from KTH/Fysik

   Author : Erik Vitols; [2022]
   Keywords : Gamma-ray burst; radiation mechanisms: thermal and non-thermal;

   Abstract : Gamma-ray bursts (GRBs) are the most luminous phenomena in the Universe, explosions whoseenergy is generated by supernovae or mergers of dense objects such as neutron stars. The GRBemission is divided into the prompt emission phase characterized by γ-ray radiation and the afterglowof lower energy radiation. READ MORE

4. 3. Assessment of weather conditions for ALMA observations of the Sun

   University essay from Luleå tekniska universitet/Institutionen för teknikvetenskap och matematik

   Author : Daniel Jakobsson; [2020]
   Keywords : Atacama Large Millimeter Array; ALMA; Solar observation;

   Abstract : The closest star to Earth is the Sun. The difference between our Sun and other stars is that the dynamics are observable with telescopes. A complex and strange part of our Sun is the chromosphere which is a part of the solar atmosphere. READ MORE

5. 4. Mapping the present-day chemical abundance structure of the Solar neighbourhood: O & Si

   University essay from Lunds universitet/Institutionen för astronomi och teoretisk fysik - Genomgår omorganisation; Lunds universitet/Astronomi - Genomgår omorganisation

   Author : Kristiina Verro; [2017]
   Keywords : astrophysics; stellar spectroscopy; abundance analysis; solar neighbourhood; massive stars; Galaxy; Physics and Astronomy;

   Abstract : Context. Large scale chemical abundance gradients in the Galactic disks, small-scale abundance structures, and the mean chemical abundance values in the Solar vicinity, are important constraints to Galactic chemo-dynamical formation and evolution models. READ MORE

6. 5. Identification of elements and molecules in the spectra of an M dwarf star using high resolution infrared spectroscopy.

   University essay from Uppsala universitet/Institutionen för fysik och astronomi

   Author : Markus Pudas; [2017]
   Keywords : M dwarf stars; line list ; spectroscopy ; high resolution infrared; telluric spectra;

   Abstract : M dwarfs are abundant and long-lived stellar objects. The formation of planets around stars in stellar systems is believed to be metallicity dependent. To determine the metallicity with synthetic spectrum analysis, the elements producing the absorption lines ofthe spectra first have to be identified. READ MORE