Structure of the Spruce Brook thrust stack at the base of the Humber Arm Allochthon, Western Newfoundland Appalachians

Spruce Brook drains a low-lying area east of the Lewis Hills and south of Blow-Me-Down Mountain in Western Newfoundland. The area is underlain by a dismembered succession of Cambrian-Ordovician platform carbonate and a succession of siliciclastic rocks assigned to the Taconic syn-tectonic flysch deposits of the Goose Tickle Group. Structurally juxtaposed against these strata are rocks of the Humber Arm Allochthon including altered ultramafic rocks and metamorphic rocks of the Bay of Islands Complex, as well as continental shelf and slope sedimentary rocks of the Humber Arm Supergroup. -- The occurrences of platform carbonate constitute thin, planar, structural slices that are bounded by thrust faults. The thrust slices are overall moderately east-dipping and imbricated from west to east. Their internal structural architecture is characterized by west-verging asymmetrical fold forms that are attributed to a combination of buckle folding and ramp-related bending. Contact relationships at the leading edge of the carbonate thrust stack indicate that strata of the Goose Tickle Group are structurally interleaved with the carbonate thrust sheets. Furthermore, the eastern trailing edge of the carbonate thrust stack is structurally overlain by the basal strata of the Humber Arm Supergroup, suggesting that the carbonate thrust stack lies as a duplex within the deformed Taconic foreland flysch succession and carries on its roof thrust the Humber Arm Allochthon. -- The thrust stack is cut by a major out-of-sequence thrust array that truncates and re-imbricates pre-existing structures related to the initial emplacement in the thrust stack. The out-of-sequence array includes a steep fault zone that carries a duplex of serpentinite and amphibolite of the Bay of Islands Complex suggesting that the emplacement and subsequent deformation of the Spruce Brook Thrust Stack is indicative of the structural interaction between the basal portion of the allochthon and the upper portion of the par-autochthonous succession during the Taconic Orogeny

Effective Field Theory Analysis on {\mu} Problem in Low-Scale Gauge Mediation

Supersymmetric models based on the scenario of gague mediation often suffer from the well-known $\mu$ problem. In this paper, we reconsider this problem in low-scale gauge mediation in terms of effective field theory analysis. In this paradigm, all high energy input soft mass can be expressed via loop expansions. If the corrections coming from messenger thresholds are small, as we assume in this letter, then RG evaluations can be taken as linearly approximation for low-scale supersymmetric breaking. Due to these observations, the parameter space can be systematically classified and studied after constraints coming from electro-weak symmetry breaking are imposed. We find that some old proposals in the literature are reproduced, and two new classes are uncovered. We refer to a microscopic model, where the specific relations among coefficients in one of the new classes are well motivated. Also, we discuss some primary phenomenologies.Comment: v3, 15 pages, refs added, to match the published versio

Youth Ambassadors Reaching Out (YARO): Lessons learned from the implementation of a youth-based cancer education program

We know that many factors contribute to the exacerbation of cancer health disparities. These inequities observed in adulthood may have originated from behaviors occurring in early adolescence. We believe that increasing awareness of cancer prevention in youth may help reduce future disparities. Our community partners identified a need for youth-oriented cancer prevention and helped design the pilot Youth Ambassadors Reaching Out (YARO) program. YARO provided cancer prevention and health disparities education and exposure to health careers to 73 middle school students between 2012-2016. YARO included didactic sessions (health disparities, smoking prevention, physical activity, nutrition), a cancer center tour, and Photovoice project. Students were encouraged to serve as ambassadors by sharing lessons learned with others. Participants demonstrated increases in cancer prevention knowledge during the program. Evaluation data revealed that students served as ambassadors by sharing information with others about healthy behaviors, improving their own health habits, and volunteering in their communities

High-Q CMOS-integrated photonic crystal microcavity devices

Integrated optical resonators are necessary or beneficial in realizations of various functions in scaled photonic platforms, including filtering, modulation, and detection in classical communication systems, optical sensing, as well as addressing and control of solid state emitters for quantum technologies. Although photonic crystal (PhC) microresonators can be advantageous to the more commonly used microring devices due to the former's low mode volumes, fabrication of PhC cavities has typically relied on electron-beam lithography, which precludes integration with large-scale and reproducible CMOS fabrication. Here, we demonstrate wavelength-scale polycrystalline silicon (pSi) PhC microresonators with Qs up to 60,000 fabricated within a bulk CMOS process. Quasi-1D resonators in lateral p-i-n structures allow for resonant defect-state photodetection in all-silicon devices, exhibiting voltage-dependent quantum efficiencies in the range of a few 10 s of %, few-GHz bandwidths, and low dark currents, in devices with loaded Qs in the range of 4,300–9,300; one device, for example, exhibited a loaded Q of 4,300, 25% quantum efficiency (corresponding to a responsivity of 0.31 A/W), 3 GHz bandwidth, and 30 nA dark current at a reverse bias of 30 V. This work demonstrates the possibility for practical integration of PhC microresonators with active electro-optic capability into large-scale silicon photonic systems.United States. Defense Advanced Research Projects Agency. Photonically Optimized Embedded MicroprocessorsUnited States. Dept. of Energy (Science Graduate Fellowship

(De)Constructing a Natural and Flavorful Supersymmetric Standard Model

Using the framework of deconstruction, we construct simple, weakly-coupled supersymmetric models that explain the Standard Model flavor hierarchy and produce a flavorful soft spectrum compatible with precision limits. Electroweak symmetry breaking is fully natural; the mu-term is dynamically generated with no B mu-problem and the Higgs mass is easily raised above LEP limits without reliance on large radiative corrections. These models possess the distinctive spectrum of superpartners characteristic of "effective supersymmetry": the third generation superpartners tend to be light, while the rest of the scalars are heavy.Comment: 36 pages, 4 figures ; v2: references added, expanded discussion of FCNC

General Messenger Gauge Mediation

We discuss theories of gauge mediation in which the hidden sector consists of two subsectors which are weakly coupled to each other. One sector is made up of messengers and the other breaks supersymmetry. Each sector by itself may be strongly coupled. We provide a unifying framework for such theories and discuss their predictions in different settings. We show how this framework incorporates all known models of messengers. In the case of weakly-coupled messengers interacting with spurions through the superpotential, we prove that the sfermion mass-squared is positive, and furthermore, that there is a lower bound on the ratio of the sfermion mass to the gaugino mass.Comment: 37 pages; minor change

A Pedagogical Review of Electroweak Symmetry Breaking Scenarios

We review different avenues of electroweak symmetry breaking explored over the years. This constitutes a timely exercise as the world's largest and the highest energy particle accelerator, namely, the Large Hadron Collider (LHC) at CERN near Geneva, has started running whose primary mission is to find the Higgs or some phenomena that mimic the effects of the Higgs, i.e. to unravel the mysteries of electroweak phase transition. In the beginning, we discuss the Standard Model Higgs mechanism. After that we review the Higgs sector of the Minimal Supersymmetric Standard Model. Then we take up three relatively recent ideas: Little Higgs, Gauge-Higgs Unification, and Higgsless scenarios. For the latter three cases, we first present the basic ideas and restrict our illustration to some instructive toy models to provide an intuitive feel of the underlying dynamics, and then discuss, for each of the three cases, how more realistic scenarios are constructed and how to decipher their experimental signatures. Wherever possible, we provide enough pedagogical details, which the beginners might find useful.Comment: 45 pages, Review based on a series of lectures; v2: 63 pages, substantially expanded, references added, to appear in `Reports on Progress in Physics

A Complete Model of Low-Scale Gauge Mediation

Recent signs of a Standard Model-like Higgs at 125 GeV point towards large A-terms in the MSSM. This presents special challenges for gauge mediation, which by itself predicts vanishing A-terms at the messenger scale. In this paper, we review the general problems that arise when extending gauge mediation to achieve large A-terms, and the mechanisms that exist to overcome them. Using these mechanisms, we construct weakly-coupled models of low-scale gauge mediation with extended Higgs-messenger couplings that generate large A-terms at the messenger scale and viable mu/B_mu-terms. Our models are simple, economical, and complete realizations of supersymmetry at the weak scale.Comment: 33 pages; v2: refs added, minor change

Parameter Space of General Gauge Mediation

We study a subspace of General Gauge Mediation (GGM) models which generalize models of gauge mediation. We find superpartner spectra that are markedly different from those of typical gauge and gaugino mediation scenarios. While typical gauge mediation predictions of either a neutralino or stau next-to-lightest supersymmetric particle (NLSP) are easily reproducible with the GGM parameters, chargino and sneutrino NLSPs are generic for many reasonable choices of GGM parameters.Comment: 8 pages, 4 figures; v2: version to appear in Phys. Lett.

LHC Phenomenology for String Hunters

We consider extensions of the standard model based on open strings ending on D-branes, with gauge bosons due to strings attached to stacks of D-branes and chiral matter due to strings stretching between intersecting D-branes. Assuming that the fundamental string mass scale is in the TeV range and the theory is weakly coupled, we discuss possible signals of string physics at the Large Hadron Collider (LHC). In previous works, direct channel excitations of Regge recurrences in parton-parton scattering supplied the outstanding new signature. The present work considers the deviation from standard model expectations for the 4-fermion processes qq\to qq and qq' \to qq', in which the s-channel excitation of string resonances is absent. In this case, we find that Kaluza-Klein recurrences at masses somewhat less than the string scale generate effective 4-fermion contact terms which can significantly enhance the dijet R ratio above its QCD value of about 0.6. The simultaneous observation of a nearby resonant structure in the dijet mass spectrum would provide a "smoking gun" for TeV scale string theory. In this work, we also show that (1) for M_{string}<3.5 TeV, the rates for various topologies arising from the pp \to Z^0 + jet channel could deviate significantly from standard model predictions and (2) that the sizeable cross sections for Regge recurrences can allow a 6\sigma discovery for string scales as large as 3 TeV after about 1 year of LHC operation at \sqrt{s} =10 TeV and \int L dt ~ 100 pb^{-1}.Comment: Typographical error in equations (17), (18), (19), and (20) has been correcte