The NMSSM Solution to the Fine-Tuning Problem, Precision Electroweak Constraints and the Largest LEP Higgs Event Excess

We present an extended study of how the Next to Minimal Supersymmetric Model easily avoids fine-tuning in electroweak symmetry breaking for a SM-like light Higgs with mass in the vicinity of 100\gev, as beautifully consistent with precision electroweak data, while escaping LEP constraints due to the dominance of $h\to aa$ decays with $m_a<2m_b$ so that a\to \tauptaum or jets. The residual $\sim 10$ branching ratio for h\to b\anti b explains perfectly the well-known LEP excess at \mh\sim 100\gev. Details of model parameter correlations and requirements are discussed as a function $\tan(\beta)$. Comparisons of fine-tuning in the NMSSM to that in the MSSM are presented. We also discuss fine-tuning associated with scenarios in which the $a$ is essentially pure singlet, has mass m_a>30\gev, and decays primarily to \gam\gam leading to an h\to aa\to 4\gam Higgs signal.Comment: 26 pages, 37 figures, published version with minor text and reference improvement

Fulde-Ferrell-Larkin-Ovchinnikov Superconducting State in CeCoIn5

We report specific heat measurements of the heavy fermion superconductor CeCoIn5 in the vicinity of the superconducting critical field H_{c2}, with magnetic field in the [110], [100], and [001] directions, and at temperatures down to 50 mK. The superconducting phase transition changes from second to first order for field above 10 T for H || [110] and H || [100]. In the same range of magnetic field we observe a second specific heat anomaly within the superconducting state. We interpret this anomaly as a signature of a Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) inhomogeneous superconducting state. We obtain similar results for H || [001], with FFLO state occupying a smaller part of the phase diagram.Comment: 4 pages, 3 figures, submitted to Phys. Rev. Letter

Unusual Higgs or Supersymmetry from Natural Electroweak Symmetry Breaking

This review provides an elementary discussion of electroweak symmetry breaking in the minimal and the next-to-minimal supersymmetric models with the focus on the fine-tuning problem -- the tension between natural electroweak symmetry breaking and the direct search limit on the Higgs boson mass. Two generic solutions of the fine-tuning problem are discussed in detail: models with unusual Higgs decays; and models with unusual pattern of soft supersymmetry breaking parameters.Comment: 23 pages, 6 figures; invited review by MPL

Anisotropy of Thermal Conductivity and Possible Signature of the Fulde-Ferrell-Larkin-Ovchinnikov state in CeCoIn_5

We have measured the thermal conductivity of the heavy-fermion superconductor CeCoIn_5 in the vicinity of the upper critical field, with the magnetic field perpendicular to the c axis. Thermal conductivity displays a discontinuous jump at the superconducting phase boundary below critical temperature T_0 ~ 1 K, indicating a change from a second to first order transition and confirming the recent results of specific heat measurements on CeCoIn_5. In addition, the thermal conductivity data as a function of field display a kink at a field H_k below the superconducting critical field, which closely coincides with the recently discovered anomaly in specific heat, tentatively identified with the appearance of the spatially inhomogeneous Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) superconducting state. Our results indicate that the thermal conductivity is enhanced within the FFLO state, and call for further theoretical investigations of the order parameter's real space structure (and, in particular, the structure of vortices) and of the thermal transport within the inhomogeneous FFLO state.Comment: 19 pages, 6 figures, submitted to Prhys. Rev.

Biochemical correlates of cardiac hypertrophy. I. Experimental model; changes in heart weight, RNA content, and nuclear RNA polymerase activity

Cardiac hypertrophy occurred in mature rats after producing supravalvular aortic stenosis with a specially designed silver clip. For 2 weeks following this procedure, heart weight, body weight, and RNA content of the myocardium were serially determined. Heart weight and RNA content increased within 24 hours of aortic banding, reaching a maximal level in 2 days and remaining elevated during the 2 weeks of observation. Nuclei were isolated and purified from heart muscle homogenates, and changes in RNA polymerase activity following aortic banding were determined. The nearest neighbor frequency of the bases of the RNA synthesized by the polymerase from nuclear preparations was identical in both the banded animals and the sham-operated controls. Both groups could thus be compared on the basis of the enzyme assay. RNA polymerase activity in nuclei from the hearts of banded rats rose rapidly when compared with the activity in sham-operated rats; peak values were reached on the second day, the earliest detectable change being around 12 hours. The increase in RNA polymerase activity represents one of the earliest biochemical events that take place in the myocardium following aortic banding

The Fulde-Ferrell-Larkin-Ovchinnikov State in the Organic Superconductor k-(BEDT-TTF)2Cu(NCS)2 as Observed in Magnetic Torque Experiments

We present magnetic-torque experiments on the organic superconductor k-(BEDT-TTF)2Cu(NCS)2 for magnetic fields applied parallel to the 2D superconducting layers. The experiments show a crossover from a second-order to a first-order transition when the upper critical field reaches 21 T. Beyond this field, which we interpret as the Pauli limit for superconductivity, the upper critical field line shows a pro-nounced upturn and a phase transition line separates the superconducting state into a low- and a high-field phase. We interpret the data in the framework of a Fulde-Ferrell-Larkin-Ovchinnikov state.Comment: 2 pages, 1 figur