update spots description, add flares (missing sources)

Physics_Thesis_Template/bib-refs.bib

@@ -1,3 +1,86 @@
+@ARTICLE{flares_1,
+       author = {{Shibata}, Kazunari and {Magara}, Tetsuya},
+        title = "{Solar Flares: Magnetohydrodynamic Processes}",
+      journal = {Living Reviews in Solar Physics},
+     keywords = {magnetic reconnection, particle acceleration, CMEs, plasmoid ejection, MHD, flux emergence, current sheet, space weather, Flares, waves, radiation, Flare, Current Sheet, Magnetic Reconnection, Flux Tube, Flux Rope},
+         year = 2011,
+        month = dec,
+       volume = {8},
+       number = {1},
+          eid = {6},
+        pages = {6},
+          doi = {10.12942/lrsp-2011-6},
+       adsurl = {https://ui.adsabs.harvard.edu/abs/2011LRSP....8....6S},
+      adsnote = {Provided by the SAO/NASA Astrophysics Data System}
+}
+
+@ARTICLE{sunspots_overview,
+       author = {{Solanki}, Sami K.},
+        title = "{Sunspots: An overview}",
+      journal = {\aapr},
+     keywords = {Sunspots, Sun: magnetic field, Sun: active regions, Sun: activity},
+         year = 2003,
+        month = jan,
+       volume = {11},
+       number = {2-3},
+        pages = {153-286},
+          doi = {10.1007/s00159-003-0018-4},
+       adsurl = {https://ui.adsabs.harvard.edu/abs/2003A&ARv..11..153S},
+      adsnote = {Provided by the SAO/NASA Astrophysics Data System}
+}
+
+@misc{sunspot_mag_field_connecting_to_second,
+  author = {Aimee Norton},
+  url = {https://kipac.stanford.edu/highlights/unravelling-magnetic-knots-sunspots},
+  title = {Unravelling magnetic knots in sunspots},
+  urldate = {2025-06-02}
+}
+
+@misc{sunspot_magfieldlines_image,
+  author = {{Australian Space Weather Forecasting Centre}},
+  url = {https://www.sws.bom.gov.au/Educational/2/2/8},
+  title = {The Magnetic Fields around Sunspots},
+  urldate = {2025-06-02}
+}
+
+@article{sunspots_magnetic_fields,
+author = {Abd Malik, Rafidah and Sathyamoorthy, Dinesh and Zakariya, Ab and Tompang, Aminudin and Tufail, Halimah and Rizal, Mohd and Kamal, Ahmad and Rajab, Abd and Lay, Lim and Kasmoni, Hanizah and Zahari, Noor and Jaafar, Jazilah and Ha, Mohd and Mat, Che and Hambali, Hasniza and Manaf, Zuraini and Mustafa, Muslihana},
+year = {2011},
+month = {11},
+pages = {165-182},
+title = {The effect of smoothed sunspot number (SSN) on HF radio communications in peninsular Malaysia for the years 2009 to 2011},
+volume = {4},
+journal = {Defence S\&T Technical Bulletin}
+}
+
+@misc{soho_project_page,
+  author = {{The SOHO Team}},
+  url = {https://soho.nascom.nasa.gov/},
+  title = {SOHO},
+  urldate = {2025-06-02}
+}
+
+@misc{soho_esa,
+  author = {{ESA}},
+  url = {https://www.esa.int/Science_Exploration/Space_Science/SOHO},
+  title = {SOHO},
+  urldate = {2025-06-02}
+}
+
+@misc{soho_nasa,
+  author = {{NASA}},
+  url = {https://science.nasa.gov/mission/soho/},
+  title = {SOHO},
+  urldate = {2025-06-02}
+}
+
+@misc{sun_photosphere_mag_field_strength,
+  title={{The Dynamic Solar Magnetic Field with Introduction}},
+  url={https://svs.gsfc.nasa.gov/4623/},
+  author={Karen Fox},
+  urldate={2025-06-02}
+}
+
 @misc{koidr25,
 
 doi = {10.26133/NEA5},
@@ -688,77 +771,77 @@ journal = {The Astrophysical Journal Supplement Series}
 @misc{tess_tess,
   title={{TESS begins its second extended mission}},
   url={https://tess.mit.edu/science/},
-  auther={TESS},
+  author={TESS},
   urldate={2025-06-01}
 }
 
 @misc{tess_extended_mission_2,
   title={{TESS begins its second extended mission}},
   url={https://tess.mit.edu/news/tess-begins-its-second-extended-mission/},
-  auther={TESS},
+  author={TESS},
   urldate={2025-06-01}
 }
 
 @misc{tess_extended_mission_1,
   title={{TESS Extended Mission}},
   url={https://archive.stsci.edu/contents/newsletters/august-2020/tess-extended-mission},
-  auther={{Mikulski Archive for Space Telescopes}},
+  author={{Mikulski Archive for Space Telescopes}},
   urldate={2025-06-01}
 }
 
 @misc{tess_nasa,
   title={TESS},
   url={https://exoplanets.nasa.gov/tess/},
-  auther={NASA},
+  author={NASA},
   urldate={2025-06-01}
 }
 
 @misc{tess_missions_and_data_mast,
   title={{Transiting Exoplanet Survey Satellite (TESS)}},
   url={https://archive.stsci.edu/missions-and-data/tess},
-  auther={{Mikulski Archive for Space Telescopes}},
+  author={{Mikulski Archive for Space Telescopes}},
   urldate={2025-06-01}
 }
 
 @misc{kepler_end_nasa_press,
   title={{NASA Retires Kepler Space Telescope}},
   url={https://www.jpl.nasa.gov/news/nasa-retires-kepler-space-telescope/},
-  auther={NASA},
+  author={NASA},
   urldate={2025-06-01}
 }
 
 @misc{kepler_end_nytimes,
   title={{Kepler, the Little NASA Spacecraft That Could, No Longer Can}},
   url={https://web.archive.org/web/20181030211627/https://www.nytimes.com/2018/10/30/science/nasa-kepler-exoplanet.html},
-  auther={Dennis Overbye},
+  author={Dennis Overbye},
   urldate={2025-06-01}
 }
 
 @misc{kepler_missions_caltech,
   title={Kepler Mission Information},
   url={https://exoplanetarchive.ipac.caltech.edu/docs/KeplerMission.html},
-  auther={{NASA Exoplanet Archive}},
+  author={{NASA Exoplanet Archive}},
   urldate={2025-06-01}
 }
 
 @misc{k2_missions_and_data_mast,
   title={K2},
   url={https://archive.stsci.edu/missions-and-data/k2},
-  auther={{Mikulski Archive for Space Telescopes}},
+  author={{Mikulski Archive for Space Telescopes}},
   urldate={2025-06-01}
 }
 
 @misc{kepler_missions_and_data_mast,
   title={Kepler},
   url={https://archive.stsci.edu/missions-and-data/kepler},
-  auther={{Mikulski Archive for Space Telescopes}},
+  author={{Mikulski Archive for Space Telescopes}},
   urldate={2025-06-01}
 }
 
 @misc{nasa_kepler_in_depth,
   title={{Kepler - In Depth}},
   url={https://science.nasa.gov/mission/kepler/in-depth/},
-  auther={NASA},
+  author={NASA},
   urldate={2025-06-01}
 }
 

Physics_Thesis_Template/content/chapter-introduction.tex

@@ -40,15 +40,39 @@ The spectral types are a way to classify the vast amount of stars into various t
 
 % Different Spectral Types
 
-\section{Flares and Spots \label{sec:intro:flares_and_spots}}
+\section{Spots and Flares \label{sec:intro:flares_and_spots}}
+
+This section will give a short overview of starspots/flares by explaining it based on the best observable example we have: the Sun.
 
 \subsection{Spots}
 
+Sunspots, or genereally speaking spots, are magnetic regions on the surface of a star that are cooler than their surroundings. Spots generally have a umbra, which is the center, and the penumbra, which is surrounding the umbra and separating it from the rest of the surface of the star (\cite{sunspots_overview}). If a spot does not have a penumbra, it is called a pore (\cite{sunspots_overview}). The size of spots varies greately, and can be up to a diameter of 60000 km on the sun and have live times from a few days to multiple months (\cite{sunspots_overview}). The umbra can be 1000 to 1900K cooler than the solar surface, while the penumbra can be 250 to 400 K cooler, which also causes them to be less bright than the rest of the photosphere (values for the sun, \cite{sunspots_overview}). This is because the strong magnetic fields (1800 to 3700 G in the umbra and 700 to 1000 G in the penumbra, compared to a few gauss in the photosphere (\cite{sunspots_overview})) limit the convection process, effecitvely reducing the thermal energy in this areas (\cite{sunspots_overview}, \cite{sun_photosphere_mag_field_strength}). An example of a sunspot can be seen in figure \ref{fig:sunspot_soho}. The image was taken by SOHO (Solar \& Heliospheric Observatory, \cite{soho_project_page}, \cite{soho_esa}, \cite{soho_nasa}). It shows a sunspot, with its umbra (dark spots) being slightly larger than Earth. The penumbra is visible in orange, and the surrounding solar photosphere is colored in yellow. Additionally an image of the whole visible suns surface at the time is included in the top right. The sunspot is located slightly left of the center.\\
+Figure \ref{fig:sunspot_magnetic_field_lines} shows an example of a sunspot, with its umbra and penumbra and magnetic field lines, with more field lines at the umbra representing a stronger magnetic field. Each spot is also magnetically linked to one or more spots of the opposite polarity, with the magnetic field varrying in complexity. A simple example of this can be seen in figure \ref{fig:sunspot_magnetic_field_lines_connecting}.
 
+\begin{figure}[pt!]
+    \centering
+    \includegraphics[width=.6\linewidth]{gfx/spots/sunspot00.png}
+    \caption{Image showing a sunspot from the 23. September 2000. Comparison of its size to Earth in the bottom left. The whole visible photosphere of the Sun is visible in the top right corner. Image taken from the SOHO image gallery (\cite{soho_project_page}).}
+    \label{fig:sunspot_soho}
+\end{figure}
+
+\begin{figure}[pt!]
+    \centering
+    \includegraphics[width=.7\linewidth]{gfx/spots/magnetic_fields_above_sunspot.png}
+    \caption{Image showing magnetic field lines coming out of a sunspot. Field lines are denser in the umbra compared to the penumbra, representing stronger magnetic fields. Image from \cite{sunspot_magfieldlines_image}.}
+    \label{fig:sunspot_magnetic_field_lines}
+\end{figure}
+
+\begin{figure}[pt!]
+    \centering
+    \includegraphics[width=.6\linewidth]{gfx/spots/image1_3.png}
+    \caption{Image showing two sunspots being connected by magnetic field lines. Image from \cite{sunspot_mag_field_connecting_to_second}.}
+    \label{fig:sunspot_magnetic_field_lines_connecting}
+\end{figure}
 
 \subsection{Flares}
 
-
+Flares are a sudden release of a huge amount of magnetic energy, which happens due to magnetic reconnection (\cite{flares_1}). The energy which is released, is the so called free magnetic energy. This is the excess energy above the ground state of the magnetic field. During a period of days to weeks this free energy is accumulated. This is done by braiding, sheering and twisting the frozen-in magnetic fields. The further the magnetic field now strays from the ground state by these kind of modifications, the more energy is built up. To release the stored energy, magnetic reconnection has to happen. For this two magnetic field lines of opposing direction need to come close. This causes a current sheet to form due to the strong current flow. In this region the frozen-in state is broken. The energy that is released during the reconnection process causes a temperature increase of the surrounding plasma (multiple 10 million K). This is then observed in soft X-ray, EUV as well as some lines in the visible spectrum and in radio. Additionally particles are accelerated and when they hit the denser chromosphere, those particles are decelerated quickly, producing hard X-ray (Bremsstrahlung). The energy release can take just a few tens of seconds, but can also last up to a few hours on the sun.
 
 % Stellar Activity, 
 

Physics_Thesis_Template/main.tex

@@ -69,6 +69,7 @@
 \newcommand{\nat}{Nature}
 \newcommand{\pasj}{Publications of the Astronomical Society of Japan}
 \newcommand{\pasp}{Publications of the Astronomical Society of the Pacific}
+\newcommand{\aapr}{The Astronomy and Astrophysics Review}
 
 \usepackage{xspace}
 \newcommand{\Figure}[1]{Figure\,\ref{#1}\xspace}