Anomaly Mediation from Randall-Sundrum to Dine-Seiberg

In this paper we reconsider the derivation of anomaly mediated supersymmetry breaking. We work in a general formalism where the F-term of the conformal compensator superfield is arbitrary. This allows for a continuous interpolation between the original derivation and a more recent Dine-Seiberg derivation of anomaly mediation. We show that the physical soft parameters are independent of the compensator F-term and results of two formalisms agree. Finally, we discuss the role of supersymmetric and non-supersymmetric thresholds in the effective low energy Lagrangian as well as the effects of explicit small mass parameters (such as mu-term) on the superpartner spectrum.Comment: 19 pages; v3, published versio

Effectively Stable Dark Matter

We study dark matter (DM) which is cosmologically long-lived because of standard model (SM) symmetries. In these models an approximate stabilizing symmetry emerges accidentally, in analogy with baryon and lepton number in the renormalizable SM. Adopting an effective theory approach, we classify DM models according to representations of $SU(3)_C\times SU(2)_L\times U(1)_Y \times U(1)_B\times U(1)_L$, allowing for all operators permitted by symmetry, with weak scale DM and a cutoff at or below the Planck scale. We identify representations containing a neutral long-lived state, thus excluding dimension four and five operators that mediate dangerously prompt DM decay into SM particles. The DM relic abundance is obtained via thermal freeze-out or, since effectively stable DM often carries baryon or lepton number, asymmetry sharing through the very operators that induce eventual DM decay. We also incorporate baryon and lepton number violation with a spurion that parameterizes hard breaking by arbitrary units. However, since proton stability precludes certain spurions, a residual symmetry persists, maintaining the cosmological stability of certain DM representations. Finally, we survey the phenomenology of effectively stable DM as manifested in probes of direct detection, indirect detection, and proton decay.Comment: 7 pages, 1 figure, 4 table

New Constraints on Isospin-Violating Dark Matter

We derive bounds on the dark matter annihilation cross-section for low-mass (5-20 GeV) dark matter annihilating primarily to up or down quarks, using the Fermi-LAT bound on gamma-rays from Milky Way satellites. For models in which dark matter-Standard Model interactions are mediated by particular contact operators, we show that these bounds can be directly translated into bounds on the dark matter-proton scattering cross-section. For isospin-violating dark matter, these constraints are tight enough to begin to constrain the parameter-space consistent with experimental signals of low-mass dark matter. We discuss possible models that can evade these bounds.Comment: 6 pages, 2 figures, LaTeX, some clarifications and minor errors corrected, citations adde

Xenophobic Dark Matter

We describe models in which dark matter is xenophobic, with significantly reduced signal strength in direct detection experiments using xenon as a target material. Such models alleviate tension between xenon-based constraints and possible signal at other direct detection experiments, and in particular regions of interest at CoGeNT and CDMS are largely below XENON100 bounds in the purely xenophobic limit. We also show the constraints from upcoming LUX results and orthogonal searches using Fermi-LAT results from line searches in dwarf spheroidals and monojet searches at CMS

Prospects of Focus Point Supersymmetry for Snowmass 2013

We briefly review the motivations and features of focus point supersymmetry and in particular the focus point region of the CMSSM. Applying the constraint that the neutralino is a thermal relic, we examine current and projected collider and dark matter constraints on the focus point region. We demonstrate that the focus point region is currently constrained by multiple dark matter experiments, and future sensitivy on multiple fronts will probe large portions of the parameter space

Isospin-Violating Dark Matter Benchmarks for Snowmass 2013

Isospin-violating dark matter (IVDM) generalizes the standard spin-independent scattering parameter space by introducing one additional parameter, the neutron-to-proton coupling ratio f_n/f_p. In IVDM the implications of direct detection experiments can be altered significantly. We review the motivations for considering IVDM and present benchmark models that illustrate some of the qualitatively different possibilities. IVDM strongly motivates the use of a variety of target nuclei in direct detection experiments.Comment: LaTeX, 5 pages, 4 figures. v2: minor figure revision

Isospin-Violating Dark Matter

Searches for dark matter scattering off nuclei are typically compared assuming that the dark matter's spin-independent couplings are identical for protons and neutrons. This assumption is neither innocuous nor well motivated. We consider isospin-violating dark matter (IVDM) with one extra parameter, the ratio of neutron to proton couplings, and include the isotope distribution for each detector. For a single choice of the coupling ratio, the DAMA and CoGeNT signals are consistent with each other and with current XENON constraints, and they unambiguously predict near future signals at XENON and CRESST. We provide a quark-level realization of IVDM as WIMPless dark matter that is consistent with all collider and low-energy bounds.Comment: 5 pages; v2: added references and fixed figures for Mac users; v3: published version; v4: fixed erroneous Ar values in table

Probing the Goldstone equivalence theorem in Heavy Weak Doublet Decays

This paper investigates the decays from heavy higgsino-like weak-doublets into Z, h bosons and missing particles. When pair-produced at the LHC, the subsequent Z, h to 2l, 2b decays in the doublet decay cascade can yield 4l, 2l 2b, and 4b + MET + jets final states. Mutual observation of any two of these channels would provide information on the the associated doublets' decay branching fractions into a Z or h, thereby probing the Goldstone equivalence relation, shedding additional light on the Higgs sector of beyond the Standard Model theories, and facilitating the discrimination of various contending models, in turn. We compare the Z/h decay ratio expected in the Minimal Supersymmetric model, the Next-to Minimal Supersymmetric model and a minimal singlet-doublet dark matter model. Additionally, we conduct a full Monte Carlo analysis of the prospects for detecting the targeted final states during 14 TeV running of the LHC in the context of a representative NMSSM benchmark model.Comment: As accepted to PRD; 15 pages, 12 figures, 5 table

Determining possible differing adverbial placement between the linguistic structures of left- and right-handed writers

This thesis has attempted to determine if there are differences, concerning adverbial placement, between the sentences of left- and right-handed writers. To make this determination, I have statistically analyzed compositions of eight graduate students (four left-handed and four right-), and two left-handed published authors\u27 (Lewis Carroll\u27s and Mark Twains) private correspondence

Volition and the Readiness Potential

In the “Libet study” the onset of movement-related brain activity preceded the reported time of the conscious intention to move, suggesting that non-conscious brain processes predetermine voluntary movements (Libet, Gleason, Wright, & Pearl, 1983). While the study’s basic results have been replicated, its validity and assumptions have been questioned. Dominik et al. (2017) provided evidence against the study’s assumption that movement and intention to move are distinct events. In this study, in which researchers did not train participants to distinguish between movement and intention, reports for intention and movement were identical. This differed from the Libet study, in which intention was reported significantly earlier in time than movement. The current study sought to replicate the findings of Dominik et al. Participants (N = 22) were assigned to one of two groups. Both groups performed the same tasks, differing only in order of task completion. In both tasks participants made mouse clicks while tracking time via an analog clock. In one task participants reported the moment they initiated their click. In the other participants reported the moment they intended to click. Crucially, when given instructions for the initial task, they were not told about the existence of the other task. Results showed an interaction of group and task, F (1, 970) = 89.571, p \u3c .001, η_p^2 = .085. The most crucial pairwise comparison, on the initial task, revealed no difference in movement and intention reports. These findings suggest that intention reports in the Libet study may be invalid