Observing muon neutrino to electron neutrino oscillations in the NOvA Experiment

Neutrino oscillations offers an insight on new physics beyond the Standard Model. The three mixing angles ($\theta_{12}$, $\theta_{13}$ and $\theta_{23}$) and the two mass splittings ($\Delta m^2_{12}$ and $\Delta m^2_{23}$) have been measured by different neutrino oscillation experiments. Some other parameters including the mass ordering of different neutrino mass eigenstates and the CP violation phase are still unknown. \nova~is a long-baseline accelerator neutrino experiment, using neutrinos from the NuMI beam at Fermilab. The experiment is equipped with two functionally identical detectors about 810 kilometers apart and 14 mrad off the beam axis. In this configuration, the muon neutrinos from the NuMI beam reach the disappearance maximum in the far detector and a small fraction of that oscillates into electron neutrinos. The sensitivity to the mass ordering and CP violation phase determination is greately enhanced. This thesis presents the \nue appearance analysis using the neutrino data collected with the \nova~experiment between February 2014 and May 2015, which corresponds to 3.45 $\times 10^{20}$ protons-on-target (POT). The $\nu_e$ appearance analysis is performed by comparing the observed \nuecc-like events to the estimated background at the far detector. The total background is predicted to be 0.95 events with 0.89 originated from beam events and 0.06 from cosmic ray events. The beam background is obtained by extrapolating near detector data through different oscillation channels, while the cosmic ray background is calculated based on out-of-time NuMI trigger data. A total of 6 electron neutrino candidates are observed in the end at the far detector which represents 3.3 $\sigma$ excess over the predicted background. The \nova~ result disfavors inverted mass hierarchy for $\delta_{cp} \in [0,0.6\pi]$ at $90 \%$ C.L

Investigating Cyberbullying in Social Media: The case of Twitter

Social media has profoundly changed how we interact with one another and the world around us. Recent research indicates that more and more people are using social media sites such as Facebook and Twitter for a significant portion of their day for various reasons such as making new friends, socializing with old friends, receiving information, and entertaining themselves. However, social media has also caused some problems. One of the problems is called social media cyberbullying which has developed over time as new social media technologies have developed over time. Social media cyberbullying has received increasing attention in recent years as the media began shedding light on the devastating consequences that bullies can bring to their victims via social media. During the past few years, there has been a sharp rise in media reports regarding the use of social media to annoy, humiliate, intimidate, bully, and threaten others, with harmful consequences such as emotional distress, anxiety, depression and in some cases, suicidal tendencies. Therefore, it is imperative for researchers to investigate the phenomenon of social media cyberbullying.Thisstudy identifies public cyberbullying messages on Twitter and then specifically examines the diffusion of these cyberbullying messages through Twitters. Java programs were developed to gather Twitter cyberbullying messages using search API offered by Twitter and then these messages were analyzed in depth to understand how people retweet cyberbullying messages on Twitter

Effectiveness of Social Media Analytics on Detecting Service Quality Metrics in the U.S. Airline Industry

During the past few decades, social media has provided a number of online tools that allow people to discuss anything freely, with an increase in mobile connectivity. More and more consumers are sharing their opinions online with others. Electronic Word of Mouth (eWOM) is the virtual communication in use; it plays an important role in customers’ buying decisions. Customers can choose to complain or to compliment services or products on their social media platforms, rather than to complete the survey offered by the providers of those services. Compared with the traditional survey, or with the air travel customer report published by U.S. Department of Transportation (DOT) each month, social media offers features that can spread information quickly and broadly. This dissertation offers a novel methodology that, by utilizing emotional sentiment analysis, can help the airline industry to improve its service quality. Longitudinal data, retrieved from Twitter, are collected from twelve U.S.-based airline companies, in order to represent airline companies in different levels and categories. The data covers three consecutive months in Quarter 2 of 2017. Applied alongside the service quality metrics of the airline industry, the benchmark datasets for each metric are created. The purpose of this dissertation is to bridge the gap in traditional methodology for a service quality measurement in the airline industry and to demonstrate the way in which socialized textual data can measure the quality of the service offered by airline service providers. In addition, sentiment analysis is applied, in order to get the sentiment score of each tweet. Emotional lexicons are used to detect the emotion expressed by the tweet in two emotional dimensions: each tweet’s Valence and Arousal are calculated. Once the SERVQUAL model is applied and the keywords to find the corresponding social media data are created for each dimension, the results show that responsiveness, assurance, and reliability are positively correlated to the AQR score that measures the service quality of airline industry. This study also finds that a large amount of negative social media data will negatively affect the AQR score. Finally, this study finds that the interaction of the sentiment score and the arousal score of textual social media data play the important role in predicting the service quality of the airline industry. Finally, an opinion-oriented information system is proposed. In the last, this study provides theory verification of SERVQUAL

Branching Fractions and CP Asymmetries of the Quasi-Two-Body Decays in Bs→K0(K‾0)K±π∓B_{s} \to K^0(\overline K^0)K^\pm \pi^\mp within PQCD Approach

Motivated by the first untagged decay-time-integrated amplitude analysis of $B_s \to K_SK^{\mp}\pi^{\pm}$ decays performed by LHCb collaboration, where the decay amplitudes are modeled to contain the resonant contributions from intermediate resonances $K^*(892)$, $K_0^*(1430)$ and $K_2^*(1430)$, we comprehensively investigate the quasi-two-body $B_{s} \to K^0/\overline{\kern -0.2em K}^0 K^{\pm}\pi^{\mp}$ decays, and calculate the branching fractions and the time-dependent $CP$ asymmetries within the perturbative QCD approach based on the $k_T$ factorization. In the quasi-two-body space region the calculated branching fractions with the considered intermediate resonances are in good agreement with the experimental results of LHCb by adopting proper $K\pi$ pair wave function, describing the interaction between the kaon and pion in the $K\pi$ pair. Furthermore,within the obtained branching fractions of the quasi-two-body decays, we also calculate the branching fractions of corresponding two-body decays, and the results consist with the LHCb measurements and the earlier studies with errors. For these considered decays, since the final states are not flavour-specific, the time-dependent $CP$ could be measured. We calculate six $CP$-violation observables, which can be tested in the ongoing LHCb experiment.Comment: 20 page

Cabibbo-Kobayashi-Maskawa-favored BB decays to a scalar meson and a DD meson

Within the perturbative QCD approach, we investigated the Cabibbo-Kobayashi-Maskawa-favored $B \to \overline{D} S$ ("$S$" denoting the scalar meson) decays on the basis of the two-quark picture. Supposing the scalar mesons are the ground states or the first excited states, we calculated the the branching ratios of 72 decay modes. Most of the branching ratios are in the range $10^{-4}$ to $10^{-7}$, which can be tested in the ongoing LHCb experiment and the forthcoming Belle-II experiment. Some decays, such as $B^+ \to \overline{D}^{(*)0} a_0^+(980/1450)$ and $B^+ \to D^{(*)-} a_0^+(980/1450)$, could be used to probe the inner structure and the character of the scalar mesons, if the experiments are available. In addition, the ratios between the $Br(B^0\to \overline{D}^{(*)0}\sigma)$ and $Br(B^0\to \overline{D}^{(*)0}f_0(980))$ provide a potential way to determine the mixing angle between $\sigma$ and $f_0(980)$. Moreover, since in the standard model these decays occur only through tree operators and have no $CP$ asymmetries, any deviation will be signal of the new physics beyond the standard model.Comment: 2 figures, 6 table

Teaching Hands-On Cyber Defense Labs to Middle School and High School Students: Our Experience from GenCyber Camps

With the high demand of the nation for next generation cybersecurity experts, it is important to design and provide hands-on labs for students at the K-12 level in order to increase their interest in cybersecurity and enhance their confidence in learning cybersecurity skills at the young age. This poster reports some preliminary analysis results from the 2016 GenCyber summer camp held at Old Dominion University (ODU), which is part of a nationwide grant program funded by the National Security Agency (NSA) and the National Science Foundation (NSF). This poster also demonstrates the design of three hands-on labs which have been devised to be age-appropriate for middle and high school students