86 research outputs found
Superpartners at LHC and Future Colliders: Predictions from Constrained Compactified M-Theory
We study a realistic top-down M-theory compactification with low-scale
effective Supersymmetry, consistent with phenomenological constraints. A
combination of top-down and generic phenomenological constraints fix the
spectrum. The gluino mass is predicted to be about 1.5 TeV. Three and only
three superpartner channels, , and
(where are Wino-like), are expected
to be observable at LHC-14. We also investigate the prospects of finding heavy
squarks and Higgsinos at future colliders. Gluino-stop-top,
gluino-sbottom-bottom associated production and first generation squark
associated production should be observable at a 100 TeV collider, along with
direct production of heavy Higgsinos. Within this framework the discovery of a
single sparticle is sufficient to determine uniquely the SUSY spectrum,
yielding a number of concrete testable predictions for LHC-14 and future
colliders, and determination of and thereby other fundamental
quantities.Comment: 19 pages, 4 figure
R-Parity Conservation from a Top Down Perspective
Motivated by results from the LHC and dark matter searches, we study the
possibility of phenomenologically viable R-parity violation in GUT
models from a top-down point of view. We show that in contrast to the more
model dependent bounds on the proton lifetime, the limits on neutrino masses
provide a robust, stringent and complementary constraint on all
GUT-based R-parity violating models. Focusing on well-motivated string/
theory GUT frameworks with mechanisms for doublet-triplet splitting and a
solution to the problems, we show that imposing the neutrino mass
bounds implies that R-parity violation is disfavored. The arguments can also be
generalized to minimal GUTs. An experimental observation of R-parity
violation would, therefore, disfavor such classes of top-down GUT models.Comment: Citations added, accepted to JHEP with minor revision
Higgs Mass Prediction for Realistic String/M Theory Vacua
Recently it has been recognized that in compactified string/M-theories that
satisfy cosmological constraints, it is possible to derive some robust and
generic predictions for particle physics and cosmology with very mild
assumptions. When the matter and gauge content below the compactification scale
is that of the MSSM, it is possible to make precise predictions. In this case,
we predict that there will be a single Standard Model-like Higgs boson with a
calculable mass 105 GeV 129 GeV depending on tan beta
(the ratio of the Higgs vevs in the MSSM). For tan beta > 7, the prediction is
: 122 GeV 129 GeV.Comment: 8 pages, 1 Figur
SelfPub 2.0
The self-publishing revolution has created a drastic increase in the number or works being published in the social sciences and humanities. This windfall of content has created an abundance that can be overwhelming, but it ultimately presents an opportunity for libraries to develop deeper and more unique collections. The preconference at the 2013 Charleston Conference focused on several interrelated topics in the self-publishing world: navigating the abundance of self-published material, libraries’ adoption of the role of publisher, vendor perspectives on self-published content and plans for the future, issues in humanities and social science acquisitions of self-published works, and an agent’s perspective on how self-publishing fits into the traditional publishing world. Speakers include librarians, publishers, vendors, and academics involved with a number of projects and efforts to pioneer this emerging field
TESS hunt for young and maturing exoplanets (THYME). III. A two-planet system in the 400 Myr Ursa major group
A.W.M. was supported through NASA's Astrophysics Data Analysis Program (80NSSC19K0583). M.L.W. was supported by a grant through NASA's K2 GO program (80NSSC19K0097). This material is based on work supported by the National Science Foundation Graduate Research Fellowship Program under grant No. DGE-1650116 to P.C.T. A.V.'s work was performed under contract with the California Institute of Technology/Jet Propulsion Laboratory funded by NASA through the Sagan Fellowship Program executed by the NASA Exoplanet Science Institute. D.D. acknowledges support from NASA through Caltech/JPL grant RSA-1006130 and through the TESS Guest Investigator Program grant 80NSSC19K1727.Exoplanets can evolve significantly between birth and maturity, as their atmospheres, orbits, and structures are shaped by their environment. Young planets (<1 Gyr) offer an opportunity to probe the critical early stages of this evolution, where planets evolve the fastest. However, most of the known young planets orbit prohibitively faint stars. We present the discovery of two planets transiting HD 63433 (TOI 1726, TIC 130181866), a young Sun-like (M∗=0.99±0.03) star. Through kinematics, lithium abundance, and rotation, we confirm that HD 63433 is a member of the Ursa Major moving group (τ=414±23 Myr). Based on the TESS light curve and updated stellar parameters, we estimate the planet radii are 2.15±0.10R⊕ and 2.67±0.12R⊕, the orbital periods are 7.11 and 20.55 days, and the orbital eccentricities are lower than about 0.2. Using HARPS-N velocities, we measure the Rossiter-McLaughlin signal of the inner planet, demonstrating that the orbit is prograde. Since the host star is bright (V=6.9), both planets are amenable to transmission spectroscopy, radial velocity measurements of their masses, and more precise determination of the stellar obliquity. This system is therefore poised to play an important role in our understanding of planetary system evolution in the first billion years after formation.PostprintPeer reviewe
- …