8,688 research outputs found

    Power Spectrum Constraints from Spectral Distortions in the Cosmic Microwave Background

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    %The content of this replacement paper is identical to the original. %We have attempted to fix the postscript so that it will print out on %a larger number of printers. Using recent experimental limits on μ\mu distortions from COBE FIRAS, and the large lever-arm spanning the damping of sub-Jeans scale fluctuations to the scale of the COBE DMR fluctuations, we set a constraint on the slope of the primordial power spectrum nn. It is possible to analytically calculate the contribution over the full range of scales and redshifts, correctly taking into account fluctuation growth and damping as well as thermalization processes. We find that the 95\% upper limit is weakly dependent on cosmological parameters, e.g. n<1.54(h=0.5)n<1.54 (h=0.5) and n<1.56(h=1.0)n<1.56 (h=1.0) for Ω0=1\Omega_0=1 with marginally weaker constraints for Ω0<1\Omega_0<1 in a flat Ω0+ΩΛ=1\Omega_0 +\Omega_\Lambda=1 universe.Comment: 8pg, uuencoded-tarred (& hopefully more compatible!) postscript, CfPA-TH-94-1

    The Physics of Microwave Background Anisotropies

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    Cosmic microwave background anisotropies provide a vast amount of information on both structure formation in the universe and the background dynamics and geometry. The full physical content and detailed structure of anisotropies can be understood in a simple and intuitive fashion through a systematic investigation of the individual mechanisms for anisotropy formation, based on elementary gravitational and fluid dynamics.Comment: 12pgs, uuencoded postscript, 5 figures included, full page color figures and stripped version available at ftp://pac2.berkeley.edu/pub/hu/physic

    Band engineering of a magnetic thin film rare earth monopnictide

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    Realizing quantum materials in few atomic layer morphologies is a key to both observing and controlling a wide variety of exotic quantum phenomena. This includes topological electronic materials, where the tunability and dimensionality of few layer materials have enabled the detection of Z2Z_2, Chern, and Majorana phases. Here, we report the development of a platform for thin film correlated, topological states in the magnetic rare-earth monopnictide (RXRX) system GdBi synthesized by molecular beam epitaxy. This material is known from bulk single crystal studies to be semimetallic antiferromagnets with Neel temperature TN=T_N = 28 K and is the magnetic analog of the non-ff-electron containing system LaBi proposed to have topological surface states. Our transport and magnetization studies of thin films grown epitaxially on BaF2_2 reveal that semimetallicity is lifted below approximately 8 crystallographic unit cells while magnetic order is maintained down to our minimum thickness of 5 crystallographic unit cells. First-principles calculations show that the non-trivial topology is preserved down to the monolayer limit, where quantum confinement and the lattice symmetry give rise to a C=2C=2 Chern insulator phase. We further demonstrate the stabilization of these films against atmospheric degradation using a combination of air-free buffer and capping procedures. These results together identify thin film RXRX materials as potential platforms for engineering topological electronic bands in correlated magnetic materials

    HTX-011 reduced pain intensity and opioid consumption versus bupivacaine HCl in bunionectomy: phase III results from the randomized EPOCH 1 study.

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    BACKGROUND AND OBJECTIVES: There is a need for local anesthetics that provide consistent analgesia through 72 hours after surgery. This study evaluates the use of HTX-011 (bupivacaine and meloxicam in Biochronomerpolymer technology), an extended-release, dual-acting local anesthetic, in reducing both postoperative pain over 72 hours and postoperative opioid use when compared with bupivacaine hydrochloride (HCl) and saline placebo. Inclusion of low-dose meloxicam in HTX-011 is designed to reduce local inflammation caused by surgery, potentiating the analgesic effect of bupivacaine. Previously, significant synergy has been observed with bupivacaine and meloxicam with both given locally together. METHODS: EPOCH 1 was a randomized, double-blind, placebo-controlled and active-controlled phase III study in subjects undergoing a primary unilateral, distal, first metatarsal bunionectomy in which subjects received either a single intraoperative dose of HTX-011, immediate-release bupivacaine HCl or saline placebo. RESULTS: A total of 412 subjects were dosed. The results for the primary and all four key secondary endpoints were statistically significant in favor of HTX-011. HTX-011 demonstrated superior, sustained pain reduction through 72 hours, significantly reduced opioid consumption and resulted in significantly more opioid-free subjects compared with saline placebo and bupivacaine HCl. Safety was similar across groups with fewer opioid-related adverse events observed in the HTX-011 group. CONCLUSIONS: HTX-011 demonstrated significant reduction in postoperative pain through 72 hours with significant reduction in opioid consumption and a significant increase in the proportion of opioid-free subjects compared with saline placebo and the most widely used local anesthetic, bupivacaine HCl. TRIAL REGISTRATION NUMBER: NCT03295721

    Can Baryonic Features Produce the Observed 100 Mpc Clustering?

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    We assess the possibility that baryonic acoustic oscillations in adiabatic models may explain the observations of excess power in large-scale structure on 100h^-1 Mpc scales. The observed location restricts models to two extreme areas of parameter space. In either case, the baryon fraction must be large (Omega_b/Omega_0 > 0.3) to yield significant features. The first region requires Omega_0 < 0.2h to match the location, implying large blue tilts (n>1.4) to satisfy cluster abundance constraints. The power spectrum also continues to rise toward larger scales in these models. The second region requires Omega_0 near 1, implying Omega_b well out of the range of big bang nucleosynthesis constraints; moreover, the peak is noticeably wider than the observations suggest. Testable features of both solutions are that they require moderate reionization and thereby generate potentially observable (about 1 uK) large-angle polarization, as well as sub-arc-minute temperature fluctuations. In short, baryonic features in adiabatic models may explain the observed excess only if currently favored determinations of cosmological parameters are in substantial error or if present surveys do not represent a fair sample of 100h^-1 Mpc structures.Comment: LaTeX, 7 pages, 5 Postscript figures, submitted to ApJ Letter
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