\chapter{Event Selection}\label{Ch:BDTSelection}
The measurement of the intrinsic electron anti-neutrino ($\overline{\nu}_e$) component in the muon anti-neutrino $\overline{\nu}_{\mu}$ T2K beam is crucial for the oscillation analysis, as it represents the largest irreducible background for the ($\overline{\nu}_{\mu} \rightarrow \overline{\nu}_e $) appearance measurement at Super-Kamiokande.
Furthermore, the near detector number of $\overline{\nu}_e$ events $\text{N}_{\text{ND}}$ is used to constrain the flux $\phi$(E) times cross-section $\sigma$(E) given detector efficiency $\epsilon$(E), as described in~\cref{sec:ImpactXsecOsc}.
The $\overline{\nu}_e$ event selection will be summarized in this chapter. This work is based
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\subsection{TPC Number of Tracks Cut}\label{subsec:nbTracksTPC}
The selected event must have at least one TPC segment, as the track's momentum and charge are measured using the TPC.
\subsection{TPC Quality Cut}
The TPC segment should consist of at least 18 hits if the track had an ECAL segment, and 36 hits otherwise.
The number of hits in the TPC segment balances the TPC performance with its systematic uncertainties, and was chosen based on previously done studies~\cite{NueSel}.
\subsection{Momentum Cut}
As mentioned in~\cref{sec:SigDef}, one of the major background is the electron coming from gammas. The low momentum region of the phase space is highly contaminated with these electrons. hence, a momentum cut was introduced, as shown in~\cref{fig:EvtSel_MomCut}.
\begin{figure}[H]
\centering
\includegraphics[scale = 0.25]{./Include/EvtSel_MomCut.png}
\caption{Introduced momentum cut to reduce the gamma background contamination. {\color{red} reproduce with MC only at this stage.}} \label{fig:EvtSel_MomCut}
\end{figure}
\subsection{BDT Cut}
The BDT works as an optimized cut in a multi-dimensional feature space, and uses the correlation between different features to improve the separation power between signal and background.
First, it calculates the test statistic (tBDT) for each track then checks if it is higher than a certain value (tBDT\_cut), it will be considered as a
This test was used in order to determine if there were too many or too few runs in a series of data. After conducting the runs test it produced a z-value of -5.9123, which indicates the amount of standard errors of the identified number of runs below the expected number of runs. The p-value indicates how extreme the z value is and with a p-value (0.0001) which is less than .05 or .1 the null hypothesis of randomness is rejected (Figure 1).
During our first run Taylor and I noticed that the car was turning way to the left. So in order to fix this we started our car as far to the right of the track as possible. After our first trials we realized that we needed to fix our string. We needed to cut the string we had attached off of our car and make a new one. When we made a new one me made it a little bit longer than the car and only hot glued it to the hook, not to the frame. Our new string had a loop in the end of it so we could put that on the toothpick. So now we understood that the toothpick did have a real purpose and we couldn’t glue the string to the mousetrap. After we made these changes we ran our car three more times.
The track begins with a steep climp, building up potential energy in the coaster car. The rest of the
2. Do not get boxed in on the track. Make sure you can move all the way off before you start across.
%The invariant mass of the electron pair, evaluated via the energy-momentum four-vectors at the beam pipe,
Flow deviation from predefined paths is not allowed. Vehicle flows can’t deviate from the preplanned paths while passing by detectors, otherwise it is necessary to define an alternative for each path.
The method used to identify the final state decay products $e^+$, $e^-$ and $\pi^{0}$ in the
approved by the instrument developers. Scores are calculated and translate into one of four risk
Powersport events used to be held on horse ovals and bicycle tracks, which gave riders of the races zero traction control. Soon, the first track would be created in Los Angeles. All of the tracks created were to be known as motordome, and they were deadly. For these certain tracks, they would use 2-by-2’s and 2-by-4’s.
Since the track consisted of two semicircles which together made up a full circle, I was able to use the radii in the circumference formula. Said formula happens to be C=2r as mentioned before. In the “r” location of the formula, I plugged in the radii which were attained in the steps prior. This was necessary in order to locate the starting positions of the runners and therefore to make the track design fair because by knowing the circumferences of the two semicircles, I am able to see the total distance which a runner in any lane will travel in one lap around the track. This can then be used to determine the offset value of each runner and therefore the starting position in both meters and
d) ASC 280-10-50-12 explains the quantitative thresholds to be applied to each operating segment. Only one of the criteria from this section applies.
The table below represents the average samples processed per hour and per step, based off the minimum, average, and maximum samples processed on exhibit 4. Separation numbers are half of the other process’s sample numbers because only 50% of samples go to separation.
During September of 2011, a group of scientists worked on an experiment called OPERA and claimed to have discovered a groundbreaking result. The OPERA experiment measured the velocity of an extremely fast particle with the name, Neutrinos. The result that was so groundbreaking was that the velocity of Neutrinos was faster than the velocity of light. The difference in velocity between a light beam and a Neutrinos particle is very small. If they raced to the moon and back a million times, the neutrinos particle would win by about a minute (“Breaking the Universal”, 1). The scientists tested Neutrinos velocity again in November and the results were the same. Scientists were worried about the results because Albert Einstein once argued that the
Controlled Variable – Same amount of air resistant (stay in the same room), same surface of what the trolley is going to accelerate on, same trolley, have the string equally stretched out every time and same tick rate of the ticker timer. The controlled variable will be controlled to create a fair test.
The report finds that proportional counting is the best method for Sr-90 determination, Cherenkov counting is the best method for Sr-89 determination and a method that incorporates different detectors is the most efficient method.