A strong electroweak phase transition in the 2HDM after LHC8

The nature of the electroweak phase transition in two-Higgs-doublet models is revisited in light of the recent LHC results. A scan over an extensive region of their parameter space is performed, showing that a strongly first-order phase transition favours a light neutral scalar with SM-like properties, together with a heavy pseudo-scalar (m_A^0 > 400 GeV) and a mass hierarchy in the scalar sector, m_H^+ gamma gamma decay channel and find that an enhancement in the branching ratio is allowed, and in some cases even preferred, when a strongly first-order phase transition is required

Role models for complex networks

We present a framework for automatically decomposing ("block-modeling") the functional classes of agents within a complex network. These classes are represented by the nodes of an image graph ("block model") depicting the main patterns of connectivity and thus functional roles in the network. Using a first principles approach, we derive a measure for the fit of a network to any given image graph allowing objective hypothesis testing. From the properties of an optimal fit, we derive how to find the best fitting image graph directly from the network and present a criterion to avoid overfitting. The method can handle both two-mode and one-mode data, directed and undirected as well as weighted networks and allows for different types of links to be dealt with simultaneously. It is non-parametric and computationally efficient. The concepts of structural equivalence and modularity are found as special cases of our approach. We apply our method to the world trade network and analyze the roles individual countries play in the global economy

Some Cosmological Implications of Hidden Sectors

We discuss some cosmological implications of extensions of the Standard Model with hidden sector scalars coupled to the Higgs boson. We put special emphasis on the conformal case, in which the electroweak symmetry is broken radiatively with a Higgs mass above the experimental limit. Our refined analysis of the electroweak phase transition in this kind of models strengthens the prediction of a strongly first-order phase transition as required by electroweak baryogenesis. We further study gravitational wave production and the possibility of low-scale inflation as well as a viable dark matter candidate.Comment: 23 pages, 8 figures; some comments added, published versio

Variational calculations on the hydrogen molecular ion

We present high-precision non-relativistic variational calculations of bound vibrational-rotational state energies for the $H_2^+$ and $D_2^+$ molecular ions in each of the lowest electronic states of $\Sigma_g$, $\Sigma_u$, and $\Pi_u$ symmetry. The calculations are carried out including coupling between $\Sigma$ and $\Pi$ states but without using the Born-Oppenheimer or any adiabatic approximation. Convergence studies are presented which indicate that the resulting energies for low-lying levels are accurate to about $10^{-13}$. Our procedure accounts naturally for the lambda-doubling of the $\Pi_u$ state.Comment: 23 pp., RevTeX, epsf.sty, 5 figs. Enhanced data in Table II, dropped 3 figs. from previous versio

Relational governance mechanisms and uncertainties in nonownership services

Entrepreneurs, managers and consumers are attracted by the promise of nonownership services in the sharing economy - to enjoy benefits of assets without bearing the costs and downsides of ownership. In many cases, reality of nonownership does not live-up to the promised value propositions, as present in the struggle of companies like Uber, BP or the entire Biopharma industry to exploit the potential of nonownership. In this article we unveil the underlying paradox of nonownership, which aims at a smart allocation of uncertainty upsides and downsides between providers and clients. We identify the potential of relational governance mechanisms to handle the uncertainty challenges apparent in nonownership. We present a pioneering case study of Rolls Royce airplane engines which unveils the contribution of relational governance in unfolding the economic benefits of nonownership

Advanced magneto-optical microscopy: Imaging from picoseconds to centimeters - imaging spin waves and temperature distributions (invited)

© 2016 Author(s).Recent developments in the observation of magnetic domains and domain walls by wide-field optical microscopy based on the magneto-optical Kerr, Faraday, Voigt, and Gradient effect are reviewed. Emphasis is given to the existence of higher order magneto-optical effects for advanced magnetic imaging. Fundamental concepts and advances in methodology are discussed that allow for imaging of magnetic domains on various length and time scales. Time-resolved imaging of electric field induced domain wall rotation is shown. Visualization of magnetization dynamics down to picosecond temporal resolution for the imaging of spin-waves and magneto-optical multi-effect domain imaging techniques for obtaining vectorial information are demonstrated. Beyond conventional domain imaging, the use of a magneto-optical indicator technique for local temperature sensing is shown

Phantom Higgs from Unparticles

A renormalizable coupling between the Higgs and a scalar unparticle operator O_U of non-integer dimension d_U < 2 gives rise, after electroweak symmetry breaking, to a mass gap in the unparticle continuum and a shift in the original Higgs mass, which can end up above or below the mass gap. We show that, besides the displaced Higgs state, a new isolated state can generically appear in the spectrum near or below the mass gap. Such state (which we call phantom Higgs) is a mixture of Higgs and unparticles and therefore has universally reduced couplings to fermions and gauge bosons. This phenomenon could cause the mass of the lightest Higgs state accessible to colliders to be much smaller than the mass expected from the SM Lagrangian.Comment: 14 LaTeX pages, 6 figure

Probing dark matter freeze-in with long-lived particle signatures: MATHUSLA, HL-LHC and FCC-hh

Collider searches for long-lived particles yield a promising avenue to probe the freeze-in production of Dark Matter via the decay of a parent particle. We analyze the prospects of probing the parameter space of Dark Matter freeze-in from the decay of neutral parent particles at the LHC and beyond, taking as a case study a freeze-in Dark Matter scenario via the Standard Model Higgs. We obtain the projected sensitivity of the proposed MATHUSLA surface detector (for MATHUSLA100 and MATHUSLA200 configurations) for long-lived particle searches to the freeze-in Dark Matter parameter space, and study its complementarity to searches by ATLAS and CMS at HL-LHC, as well as the interplay with constraints from Cosmology: Big-Bang Nucleosynthesis and Lyman-α forest observations. We then analyze the improvement in sensitivity that would come from a forward detector within a future 100 TeV pp-collider. In addition, we discuss several technical aspects of the present Dark Matter freeze-in scenario: the role of the electroweak phase transition; the inclusion of thermal masses, which have been previously disregarded in freeze-in from decay studies; the impact of 2 → 2 scattering processes on the Dark Matter relic abundance; and the interplay between freeze-in and super-WIMP Dark Matter production mechanismsJ.M.N. is supported by the Programa Atracción de Talento de la Comunidad de Madrid via grant 2017-T1/TIC-5202. B.Z. acknowledges support from the Programa Atracción de Talento de la Comunidad de Madrid under grant n. 2017-T2/TIC-5455. P.T. acknowledges support from the Deutsche Forschungsgemeinschaft (DFG) through the Emmy Noether Grant No. KA 4662/1-1 and the Collaborative Research Center TRR 257 “Particle Physics Phenomenology after the Higgs Discovery”. J.M.N. and B.Z. acknowledge support from the Spanish MINECO’s “Centro de Excelencia Severo Ochoa” Programme via grant SEV-2016-0597. J.M.N. and P.T. were supported by the European Research Council under the European Union’s Horizon 2020 program, ERC Grant Agreement 648680 (DARKHORIZONS