Charmless Hadronic B Decays at BaBar

We present recent results on charmless hadronic B decays using data collected by the BaBar detector at the PEP-II asymmetric-energy e+e- collider at the Stanford Linear Accelerator Center. We report measurements of branching fractions and charge asymmetries in several charmless two-body, three-body, and quasi-two-body decay modes. We also report measurements of polarization in charmless B decays to exclusive final states with two vector mesons.Comment: Proceedings to the Lake Louise Winter Institute 200

The Connections Between Government Structure and Direct Democracy

The purpose of this prospectus is to examine county-level contextual factors that impact direct democracy mechanisms and voter turnout. The prospectus contains two essays that build upon each other with fitting theoretical frameworks. The first essay investigates the impact of contextual factors on a county government’s decision to permit citizen initiatives. This essay applies new institutionalism theory to understand the current connections between government structure and direct democracy mechanisms within U.S. counties. County governments play a vital role in American democracy, yet little is known about why some counties permit direct democracy mechanisms while others do not. I address a gap in the literature that focuses on policy outcomes that can vary at the county-level due to election laws. Election laws that permit direct democracy mechanisms often benefit voters by initiating or repealing legislation that more closely reflects the citizenry. Given the dearth of research on direct democracy mechanisms at the county-level, I examine the 1) citizen initiative, 2) legislative referendum, 3) popular referendum, and 4) provision for recall. To investigate counties that permit direct democracy mechanisms, I focus on contextual factors that include form of government, socioeconomics, and demographics. I apply a series of cross-sectional logit regressions by using micro-level county data from the International City/County Management Association (ICMA) 2014 County Government Survey, American Community Survey (ACS), U.S. Census Bureau, and CDFI fund. Subsequently, I use the models to detect and explain variations of direct democracy that exist in the 3,031 county governments surveyed with populations between 10,000 and 500,000.https://digitalscholarship.unlv.edu/gcua_symposium/1004/thumbnail.jp

Generalized Chaplygin Gas Models tested with SNIa

The so called Generalized Chaplygin Gas (GCG) with the equation of state $p = - \frac{A}{{\rho}^{\alpha}}$ was recently proposed as a candidate for dark energy in the Universe. In this paper we confront the GCG with SNIa data. Specifically we have tested the GCG cosmology in three different classes of models with (1) $\Omega_m= 0.3$, $\Omega_{Ch}= 0.7$; (2) $\Omega_m= 0.05$, $\Omega_{Ch}= 0.95$ and (3) $\Omega_m = 0$, $\Omega_{Ch} = 1$, as well as the model withouth any assumption on $\Omega_m$. The best fitted models are obtained by minimalizing the $\chi^2$ function and $\chi^2$ levels in the $(A_0, \alpha)$ plane. We supplemented our analysis with confidence intervals in the $(A_0, \alpha)$ plane, as well as one-dimensional probability distribution functions for models parameter. The general conclusion is that SNIa data strongly support the Chaplygin gas (with $\alpha = 1$). Extending our analysisby relaxing the flat prior lead to the result that even though the best fitted values of $\Omega_k$ are formally non-zero, still they are close to flat case. It should be viewed as an advantage of the GCG model since in similar analysisof $\Lambda$CDM model high negative value of $\Omega_{k}$ were found to be bestfitted to the data and independent inspiration from CMBR and extragalactic astronomy has been invoked to fix the curvature problem. Our results show clearly that in Generalized Chaplygin Gas cosmology distant $z >1$ supernovae should be brighter than in $\Lambda$CDM model.This prediction seems to be confirmed with new Riess high redshift SNIa sample. Moreover, we argue that with the future SNAP data it would be possible to differentiate between models with various value of $\alpha$ parameter and/or discriminated between GCG, Cardassian and $\Lambda$CDM modelsComment: 54 pages 29 figures improved version analysis flat prior relaxed high redshift Riess SNIa sample include

Results from the commissioning of the ATLAS Pixel detector

The ATLAS Pixel detector is a high-resolution, low-noise silicon-based device designed to provide tracking and vertexing information within a distance of 12 cm from the LHC beam axis. It consists of approximately 80 million pixel channels with radiation-hard front-end electronics connected through optical fibers to a custom-controlled DAQ system away from the detector. Following the successful installation of the detector in June 2007, an intense commissioning period was conducted in the year 2008 and more than 400,000 cosmic-ray tracks were recorded in conjunction with other ATLAS sub-detectors. By the end of the year, 96% of the detector was tuned, calibrated, and taking data at 99.8% tracking hit efficiency and with noise occupancy at the 10^-10 level. We present here the results of the commissioning, calibration, and data-taking as well as the outlook for future performance with LHC collision-based data.Comment: 3 pages. Part of the proceedings of the TIPP09 conference, held at Tsukuba, Japan. Updated the figures in v.2 to reflect the version published in NIM A

The wave nature of continuous gravitational waves from microlensing

Gravitational wave predicted by General Relativity is the transverse wave of spatial strain. Several gravitational waveform signals from binary black holes and from a binary neutron star system accompanied by electromagnetic counterparts have been recorded by advanced LIGO and advanced Virgo. In analogy to light, the spatial fringes of diffraction and interference should also exist as the important features of gravitational waves. We propose that observational detection of such fringes could be achieved through gravitational lensing of continuous gravitational waves. The lenses would play the role of the diffraction barriers. Considering peculiar motions of the observer, the lens and the source, the spatial amplitude variation of diffraction or interference fringes should be detectable as an amplitude modulation of monochromatic gravitational signal.Comment: Accepted for publication in The Astrophysical Journa