50 research outputs found
New Fixed-Target Experiments to Search for Dark Gauge Forces
Fixed-target experiments are ideally suited for discovering new MeV-GeV mass
U(1) gauge bosons through their kinetic mixing with the photon. In this paper,
we identify the production and decay properties of new light gauge bosons that
dictate fixed-target search strategies. We summarize existing limits and
suggest five new experimental approaches that we anticipate can cover most of
the natural parameter space, using currently operating GeV-energy beams and
well-established detection methods. Such experiments are particularly timely in
light of recent terrestrial and astrophysical anomalies (PAMELA, FERMI,
DAMA/LIBRA, etc.) consistent with dark matter charged under a new gauge force.Comment: 14 pages + 6 page appendix and refs, 11 figure
Solitonic supersymmetry restoration
Q-balls are a possible feature of any model with a conserved, global U(1)
symmetry and no massless, charged scalars. It is shown that for a broad class
of models of metastable supersymmetry breaking they are extremely influential
on the vacuum lifetime and make seemingly viable vacua catastrophically short
lived. A net charge asymmetry is not required as there is often a significant
range of parameter space where statistical fluctuations alone are sufficient.
This effect is examined for two supersymmetry breaking scenarios. It is found
that models of minimal gauge mediation (which necessarily have a messenger
number U(1)) undergo a rapid, supersymmetry restoring phase transition unless
the messenger mass is greater than 10^8 GeV. Similarly the ISS model, in the
context of direct mediation, quickly decays unless the perturbative
superpotential coupling is greater than the Standard Model gauge couplings.Comment: 17 pages, 3 figures, minor comments added, accepted for publication
in JHE
The Vehicle, Fall 1992
Table of Contents
DeconstructivismPeter F. Essigpage 5
Homecoming Pep RallyPeter F. Essigpage 6
McAfee GymnasiumWalt Howardpage 7
Morton ParkAnn Moutraypage 9
Why The Willows WeepPeter F. Essigpage 10
UntitledStephen P. Carmodypage 10
A Stranger\u27s MorningBen Hausmannpage 11
deMONSTERative pronounsJoAnna Wolaverpage 12
2.5%Jill S. Pilonpage 13
The BottleStacey Kruegerpage 14
Suppression Jean K. Graypage 15
ProgressStacey Kruegerpage 16
Daily LessonsJennifer Moropage 17
Sunset TheaterMichelle R. Hokepage 20
Eagle GT\u27sJarrod T. Shieldspage 21
New HouseRandy Lisspage 22
UntitledStephen P. Carmodypage 23
Renting Classics on a Saturday NightNancy Jamespage 24
UntitledJacqueline Hallpage 25
Alone While He SleepsSandy Beauchamppage 26
Sand and SeaThomas Schnarrepage 27
loveMichelle R. Hokepage 28
Backward Ass Junkie FunkSandy Beauchamppage 28
These Things You KeepTom McGrathpage 29
Springhill CrestRobert M. Reutherpage 30
The Pass OverLarry Irvinpage 31
The Stolen ChildTom McGrathpage 32
Before the Recycling KickWalt Howardpage 37
Authors\u27 Pagepage 38https://thekeep.eiu.edu/vehicle/1058/thumbnail.jp
Simplified Models for LHC New Physics Searches
This document proposes a collection of simplified models relevant to the
design of new-physics searches at the LHC and the characterization of their
results. Both ATLAS and CMS have already presented some results in terms of
simplified models, and we encourage them to continue and expand this effort,
which supplements both signature-based results and benchmark model
interpretations. A simplified model is defined by an effective Lagrangian
describing the interactions of a small number of new particles. Simplified
models can equally well be described by a small number of masses and
cross-sections. These parameters are directly related to collider physics
observables, making simplified models a particularly effective framework for
evaluating searches and a useful starting point for characterizing positive
signals of new physics. This document serves as an official summary of the
results from the "Topologies for Early LHC Searches" workshop, held at SLAC in
September of 2010, the purpose of which was to develop a set of representative
models that can be used to cover all relevant phase space in experimental
searches. Particular emphasis is placed on searches relevant for the first
~50-500 pb-1 of data and those motivated by supersymmetric models. This note
largely summarizes material posted at http://lhcnewphysics.org/, which includes
simplified model definitions, Monte Carlo material, and supporting contacts
within the theory community. We also comment on future developments that may be
useful as more data is gathered and analyzed by the experiments.Comment: 40 pages, 2 figures. This document is the official summary of results
from "Topologies for Early LHC Searches" workshop (SLAC, September 2010).
Supplementary material can be found at http://lhcnewphysics.or
Dark sectors 2016 Workshop: community report
This report, based on the Dark Sectors workshop at SLAC in April 2016,
summarizes the scientific importance of searches for dark sector dark matter
and forces at masses beneath the weak-scale, the status of this broad
international field, the important milestones motivating future exploration,
and promising experimental opportunities to reach these milestones over the
next 5-10 years
US Cosmic Visions: New Ideas in Dark Matter 2017: Community Report
This white paper summarizes the workshop "U.S. Cosmic Visions: New Ideas in
Dark Matter" held at University of Maryland on March 23-25, 2017.Comment: 102 pages + reference
Stellar kinematics and metallicities in the ultra-faint dwarf galaxy Reticulum II
Based on data obtained from the ESO Science Archive Facility under request number 157689
Search for gamma-ray emission from DES dwarf spheroidal galaxy candidates with Fermi-LAT data
Due to their proximity, high dark-matter (DM) content, and apparent absence of non-thermal processes, Milky Way dwarf spheroidal satellite galaxies (dSphs) are excellent targets for the indirect detection of DM. Recently, eight new dSph candidates were discovered using the first year of data from the Dark Energy Survey (DES). We searched for gamma-ray emission coincident with the positions of these new objects in six years of Fermi Large Area Telescope data. We found no significant excesses of gamma-ray emission. Under the assumption that the DES candidates are dSphs with DM halo properties similar to the known dSphs, we computed individual and combined limits on the velocity-averaged DM annihilation cross section for these new targets. If the estimated DM content of these dSph candidates is confirmed, they will constrain the annihilation cross section to lie below the thermal relic cross section for DM particles with masses ≲ 20 {GeV} annihilating via the b\bar{b} or tau+tau- channels
Neutrinos
229 pages229 pages229 pagesThe Proceedings of the 2011 workshop on Fundamental Physics at the Intensity Frontier. Science opportunities at the intensity frontier are identified and described in the areas of heavy quarks, charged leptons, neutrinos, proton decay, new light weakly-coupled particles, and nucleons, nuclei, and atoms