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Physics_Thesis_Template/content/chapter-results.tex
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@@ -180,6 +180,12 @@ This section contains a selection of results for individual stars. The results f
\subsection{BD-08 995}
BD-08 995, also known by TIC 43472154, is a G type star with a surface temperature of 5231.2 K, which is \textasciitilde87 pc away. It is a very active solar like star, producing over 200 superflares per year (\cite{tess_1st_year_superflares}). It has a rotational period of 2.8 days (\cite{tess_1st_year_superflares}). There are two TESS lightcurves available, sectors 5 and 32.\\
Looking at figure \ref{fig:BD-08_995-Flarecount-10_Bins}, which shows the flare distribution across the normalized phase of the folded lightcurves with 10 bins, it shows a clear peak of flares appearance in the lightcurve minima at phase $1 \pi$. The errorbars of this wide peak only overlap with the first bin of the plot at phase $0 \pi$.
This bin belong to the phase maxima which also shows slight increase in flare activity at phase $0/2 \pi$ compared to the transition regions at around phase $0.5 \pi$ (maxima to minima) and $1.5 \pi$ (minima to maxima). Considering errors for this, the errorbars of the bins at the phase maxima overlap with those of the transition regions.\\
Figure \ref{fig:BD-08_995-Flarecount-30_Bins} shows the same data just with 30 bins instead of 10. Ignoring the errorbars, it shows a similar picture as the previous figure. But due to the low number of total detected flares, and a the relatively large bin count, the errorbars become large compared to the individual bins. Due to this, the errorbars of most bins overlap with each other, with the exceptions of the the first bin at phase $0 \pi$ and the bin at phase \textasciitilde$1.1 \pi$, whichs erorbars only overlap with other higher bins like the ones at phase \textasciitilde$0.9 \pi$ and \textasciitilde$1.4 \pi$.
\begin{figure}[pt!]
\centering
\begin{subfigure}[b]{.95\textwidth}
@@ -199,6 +205,16 @@ This section contains a selection of results for individual stars. The results f
\label{fig:BD-08_995-Flarecount}
\end{figure}
The distribution of normalized flare peaks for BD-08 995 in figure \ref{fig:BD-08_995-flarepeaks_1.2} shows that the highest flare peak appeared at around phase $0.1 \pi$ with a peak of \textasciitilde1.11. Other high flare peaks were detected at phases \textasciitilde$1 \pi$ and \textasciitilde$1.9 \pi$. Furthermore the flares around phase $1 \pi$ seem to have higher average peak.
\begin{figure}[pt!]
\includegraphics[width=.95\textwidth]{plots/sine/BD-08_995/BD-08\space\space\space995-Flarepeaks_maxY-1.2.png}
\caption{Distribution of flare peaks in relation to the normalized phase at which they occured for BD-08 995. Y-Axis shows the flare peak and is limited to the value of the highest peak detected. The x-axis shows the normalized phase.}
\label{fig:BD-08_995-flarepeaks_1.2}
\end{figure}
Looking at the folded TESS lightcurves of sector 5 (\ref{fig:BD-08_995-TESS5_foldedLC}) and 32 (\ref{fig:BD-08_995-TESS32_foldedLC}) one can see the earlier presented distribution of flares and their peaks. In TESS sector 5 there appear comparatively many flares at around phase $-0.2$ (not normalized). The highest detected flare peak which was mentioned prior was detected in the TESS sector 32 lightcurve at phase $-1.2$.
\begin{figure}[pt!]
\centering
\begin{subfigure}[b]{.95\textwidth}
@@ -221,6 +237,10 @@ This section contains a selection of results for individual stars. The results f
\FloatBarrier
\subsection{TYC 1360-957-1}
Not much is published about TYC 1360-957-1. It has been categorized as spectral type K on SIMBAD (\cite{simbad}). It has the TESS Input Catalogue number 247117382, and has been observed by TESS in sectors 44, 45 and 46.\\
Looking at the flare distribution histogram with 10 bins for this star in figure \ref{fig:TYC_1360-957-1-Flarecount-10_Bins} one can see that the highest peaks in order are at phase \textasciitilde$0.7 \pi$, \textasciitilde$0.4 \pi$ and \textasciitilde$1.2 \pi$. The last one being two bins wide. The first two are, including error, above their surrounding bins, while for the third peak, the second peaks errorbar overlaps with those of the smaller bins.
Looking at the histogram with 30 bins of the same dataset (figure \ref{fig:TYC_1360-957-1-Flarecount-30_Bins}), the first 2 peaks mentioned for the histogram with 10 bins are still visible. But compared to the privious figure, the low number of flares result in a rather large error. This causes the errorbars of the two mentioned bin peaks to overlap with the surrounding bins which could be estimated to be the average.
\begin{figure}[pt!]
\centering
\begin{subfigure}[b]{.95\textwidth}
@@ -240,6 +260,17 @@ This section contains a selection of results for individual stars. The results f
\label{fig:TYC_1360-957-1-Flarecount}
\end{figure}
Figure \ref{fig:TYC_1360-957-1-flarepeaks_1.31} presents the overall distribution on the normalized phase detected for TYC 1360-957-1 in this study. The three highest flare peaks detected were at a normalized phase of \textasciitilde$0.8 \pi$, which is very close to the phase minimum at $1 \pi$. Three more higher flare peaks stand out at phase $1.2 \pi$. While they are not as high as the previous three, they have a higher peak than the rest of the detected flares.
\begin{figure}[pt!]
\includegraphics[width=.95\textwidth]{plots/sine/TYC_1360-957-1/TYC 1360-957-1-Flarepeaks_maxY-1.3130771478482715.png}
\caption{Distribution of flare peaks in relation to the normalized phase at which they occured for TYC 1360-957-1. Y-Axis shows the flare peak and is limited to the value of the highest peak detected. The x-axis shows the normalized phase.}
\label{fig:TYC_1360-957-1-flarepeaks_1.31}
\end{figure}
The used folded lightcurves used can be seen in figure \ref{fig:TYC_1360-957-1-TESS_foldedLCs}. This figure is split into the three different TESS sectors. In \subref{fig:TYC_1360-957-1-TESS44_foldedLC} sector 44 is visible. The lowest point of the folded lightcurve is slightly shifted from the center, which represents the lowest point of the sine fit. One can also see that two large flares happened at this point.
No such large flares can be seen in \subref{fig:TYC_1360-957-1-TESS45_foldedLC}, unlike in \subref{fig:TYC_1360-957-1-TESS46_foldedLC} which shows a large flare again.
\begin{figure}[pt!]
\centering
\begin{subfigure}[b]{.95\textwidth}
@@ -269,6 +300,10 @@ This section contains a selection of results for individual stars. The results f
\FloatBarrier
\subsection{TYC 4595-107-1}
TYC 4595-107-1, also known as TIC 394030788, is a G type star with an effective temperature of 5231 K, a radius of 0.9 $R_\odot$ (\cite{tess_2nd_year_superflares}, \cite{superflare_rate_variation_g_type}), mass of 0.89 $M_\odot$ (\cite{superflare_rate_variation_g_type}) and a rotational period of 3.3 days (\cite{tess_2nd_year_superflares}, \cite{superflare_rate_variation_g_type}) and was observed in 20 TESS sectors. The folded lightcurves for TYC 4595-107-1 can be found in appendix \ref{apB:TYC_4595-107-1}.\\
The first histogram, figure \ref{fig:TYC_4595-107-1-Flarecount-10_Bins}, with 10 bins shows the accumulated data for all 20 observed lightcurves. Due to the high number of available lightcurves, and TYC 4595-107-1 being a very active star (\cite{tess_2nd_year_superflares}, \cite{superflare_rate_variation_g_type}), the total flare count is very high. There seems to be a base level of flares per bin of around 30 over the phase, with a large and two bin wide peak at around phase $0.6 to 0.8 \pi$. This increase in flares is high enough to be outside of the error of the base amount of flares. Another peak, even though less certain as its errorbar overlaps with the surrounding bins, appears at the bin at phase $1.9 \pi$. A similar increase in flares can be seen at the bin at $0.2 \pi$.\\
The histogram with 30 bins (figure \ref{fig:TYC_4595-107-1-Flarecount-30_Bins}) shows a similar result. It shows a large increase in flares around phase $0.6 to 1 \pi$, as well at at $1.9 to 0.1 \pi$ and $0.4 \pi$. Only the first mentioned peak managed to be large enough though, to not have overlapping errors with the surrounding lower count bins.
\begin{figure}[pt!]
\centering
\begin{subfigure}[b]{.95\textwidth}
@@ -357,6 +392,13 @@ Figure \ref{fig:V471Tau-flarepeaks_1.053} shows the normalized phase and peak of
\FloatBarrier
\subsection{V* HK Aqr}
HK Aqr is a M dwarf with a mass of 0.57 $M_\odot$, a radius of 0.53 $R_\odot$ and is around 22.3 pc away from our solar system. Its effective temperature is aroun 3800 K (\cite{conch_shell_m_dwarfs}). It was observed in four TESS sectors.
HK Aqr is mentioned here, as it is a star, for which the optimize fold algorithm partially broke. This happened for its lightcurves for the sectors 29 and 42. The algorithm found for both periodograms a second signal for a possible period. This resulted in the folded lightcurves seen in figures \ref{fig:HKAqr-TESS29_foldedLC} and \ref{fig:HKAqr-TESS42_foldedLC}. Figures \ref{fig:HKAqr-Flarecount-10_Bins} and \ref{fig:HKAqr-Flarecount-30_Bins} were created with this dataset.\\
In figure \ref{fig:HKAqr-Flarecount-10_Bins} one can see an increase in flares at around phase $1.3 \pi$. This peak is high enough to be outside the error range of the lower flare count bins between phase $0 to 1 \pi$. Figure \ref{fig:HKAqr-Flarecount-30_Bins} paints a similar picture. Additionally it shows a peak at phase $0 \pi$ though, which is during the phase maximum, as well as one at around phase $1.6 \pi$ which is in the transition from minima to maxima.\\
Figures \ref{fig:HKAqr-Flarecount-10_Bins_Period} and \ref{fig:HKAqr-Flarecount-30_Bins_Period} show the historgrams for the data of the two folded TESS lightcurves of sectors 29 and 42 which were flagged as period folded with 10 and 30 bins respectively. The folded lightcurves can be found in figure \ref{fig:HKAqr-TESS_foldedLCs_Period}.
In figure \ref{fig:HKAqr-Flarecount-10_Bins_Period} the overall flare distribution seems to be relatively high from phase $0.2 \pi$ to $1.4 \pi$, with a peak at phase $1.2 \pi$. The amount of detected flares during the maximum of the lightcurves at phase $1.8$ to $0.2 \pi$ is low compared to that. Even including the errorbars it cannot reach the previous bins. An additional dip of the same flare count can be seen at phase $1.5 \pi$.
The flare count in figure \ref{fig:HKAqr-Flarecount-30_Bins_Period} is very low. Due to this all errorbars overlap. Nontheless there are two bins which stand out at phases \textasciitilde$0.4 \pi$ and \textasciitilde$1.25 \pi$ which would be in the transition from maxima to minima, and shortly after the minima respectively.
\begin{figure}[pt!]
\centering
\begin{subfigure}[b]{.95\textwidth}
@@ -391,7 +433,11 @@ Figure \ref{fig:V471Tau-flarepeaks_1.053} shows the normalized phase and peak of
\caption{TESS Sector 29}
\label{fig:HKAqr-TESS29_foldedLC}
\end{subfigure}
\vspace{1em}
\caption{Folded lightcurves for V* HK Aqr. The blue lines shows the sine fits calculated. The red crosses indicate the detected flare peaks.}
\label{fig:HKAqr-TESS_foldedLCs1}
\end{figure}
\begin{figure}[pt!]
\centering
\begin{subfigure}[b]{.95\textwidth}
\centering
\includegraphics[width=\linewidth]{plots/sine/HKAqr/V_star_ HK Aqr_TESS-42-foldedLC-marked_fit_flares.png}
@@ -405,7 +451,7 @@ Figure \ref{fig:V471Tau-flarepeaks_1.053} shows the normalized phase and peak of
\label{fig:HKAqr-TESS69_foldedLC}
\end{subfigure}
\caption{Folded lightcurves for V* HK Aqr. The blue lines shows the sine fits calculated. The red crosses indicate the detected flare peaks.}
\label{fig:HKAqr-TESS_foldedLCs}
\label{fig:HKAqr-TESS_foldedLCs2}
\end{figure}
\begin{figure}[pt!]