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Exploring the Lived Experience of Kumeyaay College Graduates
The purpose of this study was to explore the lived experience during participation in higher education of Kumeyaay Indian Nation college graduates. Specifically, the study investigated the factors graduates perceived to contribute to their persistence and attainment of a baccalaureate degree within six years of enrollment at a four-year institution of higher education. Participants included twelve participants who self-identified as members of the Kumeyaay Indian Nation who had earned at least a baccalaureate degree from a four-year institution of higher education within six years of enrollment. MaxQDA was used to organize, code, and synthesize interview transcripts to develop themes pertaining to Kumeyaay college student perceived factors that supported persistence and degree attainments. Four themes emerged from the data: cultural and identity revitalization, discovering the leader within, a support network paradox and what is the alternative? The research findings unveiled significant implications for practice in higher education such as collaborating with local Native American communities to leverage cultural and identity development, empowering Native students with greater opportunities for leadership engagement, establishing Native community-center support networks, and fostering mentorship and opportunities to give back among college graduates from the Kumeyaay Indian Nation. Future research could explore the perceived factors that Kumeyaay college student’s believe impacted persistence and degree attainment with a focus on the selected area of study; whether a student grew up on or off a reservation; or using a larger sample across specific types of four-year institutions of higher education
Charles Lindbergh: A Religious Biography of America\u27s Most Infamous Pilot
The narrative surrounding Charles Lindbergh’s life has been as varying and complex as the man himself. Once best known as an aviator—the first to complete a solo nonstop transatlantic flight—he has since become increasingly identified with his sympathies for white supremacy, eugenics, and the Nazi regime in Germany. Underexplored amid all this is Lindbergh’s spiritual life. What beliefs drove the contradictory impulses of this twentieth-century icon?https://spark.bethel.edu/faculty-books/1003/thumbnail.jp
Search for a heavy resonance decaying to a top quark and a W boson at √s = 13 TeV in the fully hadronic final state
A search for a heavy resonance decaying to a top quark and a W boson in the fully hadronic final state is presented. The analysis is performed using data from proton-proton collisions at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 137 fb−1 recorded by the CMS experiment at the LHC. The search is focused on heavy resonances, where the decay products of each top quark or W boson are expected to be reconstructed as a single, large-radius jet with a distinct substructure. The production of an excited bottom quark, b*, is used as a benchmark when setting limits on the cross section for a heavy resonance decaying to a top quark and a W boson. The hypotheses of b* quarks with left-handed, right-handed, and vector-like chiralities are excluded at 95% confidence level for masses below 2.6, 2.8, and 3.1 TeV, respectively. These are the most stringent limits on the b* quark mass to date, extending the previous best limits by almost a factor of two. [Figure not available: see fulltext.
Observation of tW production in the single-lepton channel in pp collisions at √s = 13 TeV
A measurement of the cross section of the associated production of a single top quark and a W boson in final states with a muon or electron and jets in proton-proton collisions at s = 13 TeV is presented. The data correspond to an integrated luminosity of 36 fb−1 collected with the CMS detector at the CERN LHC in 2016. A boosted decision tree is used to separate the tW signal from the dominant tt ¯ background, whilst the subleading W+jets and multijet backgrounds are constrained using data-based estimates. This result is the first observation of the tW process in final states containing a muon or electron and jets, with a significance exceeding 5 standard deviations. The cross section is determined to be 89 ± 4 (stat) ± 12 (syst) pb, consistent with the standard model. [Figure not available: see fulltext.
Measurement of b jet shapes in proton-proton collisions at √s = 5.02 TeV
We present the first study of charged-hadron production associated with jets originating from b quarks in proton-proton collisions at a center-of-mass energy of 5.02 TeV. The data sample used in this study was collected with the CMS detector at the CERN LHC and corresponds to an integrated luminosity of 27.4 pb−1. To characterize the jet substructure, the differential jet shapes, defined as the normalized transverse momentum distribution of charged hadrons as a function of angular distance from the jet axis, are measured for b jets. In addition to the jet shapes, the per-jet yields of charged particles associated with b jets are also quantified, again as a function of the angular distance with respect to the jet axis. Extracted jet shape and particle yield distributions for b jets are compared with results for inclusive jets, as well as with the predictions from the pythia and herwig++ event generators. [Figure not available: see fulltext.
Combined searches for the production of supersymmetric top quark partners in proton–proton collisions at √s=13Te
A combination of searches for top squark pair production using proton–proton collision data at a center-of-mass energy of 13Te at the CERN LHC, corresponding to an integrated luminosity of 137fb-1 collected by the CMS experiment, is presented. Signatures with at least 2 jets and large missing transverse momentum are categorized into events with 0, 1, or 2 leptons. New results for regions of parameter space where the kinematical properties of top squark pair production and top quark pair production are very similar are presented. Depending on the model, the combined result excludes a top squark mass up to 1325Ge for a massless neutralino, and a neutralino mass up to 700Ge for a top squark mass of 1150Ge. Top squarks with masses from 145 to 295Ge, for neutralino masses from 0 to 100Ge, with a mass difference between the top squark and the neutralino in a window of 30Ge around the mass of the top quark, are excluded for the first time with CMS data. The results of theses searches are also interpreted in an alternative signal model of dark matter production via a spin-0 mediator in association with a top quark pair. Upper limits are set on the cross section for mediator particle masses of up to 420Ge
Search for W′ bosons decaying to a top and a bottom quark at s=13TeV in the hadronic final state
A search is performed for W′ bosons decaying to a top and a bottom quark in the all-hadronic final state, in proton-proton collisions at a center-of-mass energy of 13 TeV. The analyzed data were collected by the CMS experiment between 2016 and 2018 and correspond to an integrated luminosity of 137 fb−1. Deep neural network algorithms are used to identify the jet initiated by the bottom quark and the jet containing the decay products of the top quark when the W boson from the top quark decays hadronically. No excess above the estimated standard model background is observed. Upper limits on the production cross sections of W′ bosons decaying to a top and a bottom quark are set. Both left- and right-handed W′ bosons with masses below 3.4 TeV are excluded at 95% confidence level, and the most stringent limits to date on W′ bosons decaying to a top and a bottom quark in the all-hadronic final state are obtained
Search for the rare decay of the W boson into a pion and a photon in proton-proton collisions at s=13TeV
A search is performed for the rare decay W±→π±γ in proton-proton collisions at s=13TeV. Data corresponding to an integrated luminosity of 137fb−1 were collected during 2016 to 2018 with the CMS detector. This analysis exploits a novel search strategy based on W boson production in top quark pair events. An inclusive search for the W±→π±γ decay is not optimal at the LHC because of the high trigger thresholds. Instead, a trigger selection is exploited in which the W boson originating from one of the top quarks is used to tag the event in a leptonic decay. The W boson emerging from the other top quark is used to search for the W±→π±γ signature. Such decays are characterized by an isolated track pointing to a large energy deposit, and by an isolated photon of large transverse momentum. The presence of b quark jets reduces the background from the hadronization of light-flavor quarks and gluons. The W±→π±γ decay is not observed. An upper exclusion limit is set to this branching fraction, corresponding to 1.50×10−5 at 95% confidence level, whereas the expected upper exclusion limit is 0.85−0.29+0.52×10−5
Measurement of the Wγ Production Cross Section in Proton-Proton Collisions at s =13 TeV and Constraints on Effective Field Theory Coefficients
A fiducial cross section for Wγ production in proton-proton collisions is measured at a center-of-mass energy of 13 TeV in 137 fb-1 of data collected using the CMS detector at the LHC. The W→eν and μν decay modes are used in a maximum-likelihood fit to the lepton-photon invariant mass distribution to extract the combined cross section. The measured cross section is compared with theoretical expectations at next-to-leading order in quantum chromodynamics. In addition, 95% confidence level intervals are reported for anomalous triple-gauge couplings within the framework of effective field theory
Search for dark photons in Higgs boson production via vector boson fusion in proton-proton collisions at √s = 13 TeV
A search is presented for a Higgs boson that is produced via vector boson fusion and that decays to an undetected particle and an isolated photon. The search is performed by the CMS collaboration at the LHC, using a data set corresponding to an integrated luminosity of 130 fb−1, recorded at a center-of-mass energy of 13 TeV in 2016–2018. No significant excess of events above the expectation from the standard model background is found. The results are interpreted in the context of a theoretical model in which the undetected particle is a massless dark photon. An upper limit is set on the product of the cross section for production via vector boson fusion and the branching fraction for such a Higgs boson decay, as a function of the Higgs boson mass. For a Higgs boson mass of 125 GeV, assuming the standard model production rates, the observed (expected) 95% confidence level upper limit on the branching fraction is 3.5 (2.8)%. This is the first search for such decays in the vector boson fusion channel. Combination with a previous search for Higgs bosons produced in association with a Z boson results in an observed (expected) upper limit on the branching fraction of 2.9 (2.1)% at 95% confidence level. [Figure not available: see fulltext.