All-sky search for long-duration gravitational wave transients with initial LIGO

We present the results of a search for long-duration gravitational wave transients in two sets of data collected by the LIGO Hanford and LIGO Livingston detectors between November 5, 2005 and September 30, 2007, and July 7, 2009 and October 20, 2010, with a total observational time of 283.0 days and 132.9 days, respectively. The search targets gravitational wave transients of duration 10-500 s in a frequency band of 40-1000 Hz, with minimal assumptions about the signal waveform, polarization, source direction, or time of occurrence. All candidate triggers were consistent with the expected background; as a result we set 90% confidence upper limits on the rate of long-duration gravitational wave transients for different types of gravitational wave signals. For signals from black hole accretion disk instabilities, we set upper limits on the source rate density between 3.4×10-5 and 9.4×10-4 Mpc-3 yr-1 at 90% confidence. These are the first results from an all-sky search for unmodeled long-duration transient gravitational waves. © 2016 American Physical Society

All-sky search for long-duration gravitational wave transients with initial LIGO

We present the results of a search for long-duration gravitational wave transients in two sets of data collected by the LIGO Hanford and LIGO Livingston detectors between November 5, 2005 and September 30, 2007, and July 7, 2009 and October 20, 2010, with a total observational time of 283.0 days and 132.9 days, respectively. The search targets gravitational wave transients of duration 10-500 s in a frequency band of 40-1000 Hz, with minimal assumptions about the signal waveform, polarization, source direction, or time of occurrence. All candidate triggers were consistent with the expected background; as a result we set 90% confidence upper limits on the rate of long-duration gravitational wave transients for different types of gravitational wave signals. For signals from black hole accretion disk instabilities, we set upper limits on the source rate density between 3.4×10-5 and 9.4×10-4 Mpc-3 yr-1 at 90% confidence. These are the first results from an all-sky search for unmodeled long-duration transient gravitational waves. © 2016 American Physical Society

Constraints on cosmic strings using data from the first Advanced LIGO observing run

Cosmic strings are topological defects which can be formed in grand unified theory scale phase transitions in the early universe. They are also predicted to form in the context of string theory. The main mechanism for a network of Nambu-Goto cosmic strings to lose energy is through the production of loops and the subsequent emission of gravitational waves, thus offering an experimental signature for the existence of cosmic strings. Here we report on the analysis conducted to specifically search for gravitational-wave bursts from cosmic string loops in the data of Advanced LIGO 2015-2016 observing run (O1). No evidence of such signals was found in the data, and as a result we set upper limits on the cosmic string parameters for three recent loop distribution models. In this paper, we initially derive constraints on the string tension Gμ and the intercommutation probability, using not only the burst analysis performed on the O1 data set but also results from the previously published LIGO stochastic O1 analysis, pulsar timing arrays, cosmic microwave background and big-bang nucleosynthesis experiments. We show that these data sets are complementary in that they probe gravitational waves produced by cosmic string loops during very different epochs. Finally, we show that the data sets exclude large parts of the parameter space of the three loop distribution models we consider

Social distribution of cardiovascular disease risk factors: change among men in England 1984-1993

OBJECTIVE—To investigate change in the social distribution of some of the main risk factors for cardiovascular disease in men in England during a period when inequality in cardiovascular disease mortality widened
DESIGN—Age standardised comparison of the social distribution of seven known risk factors for cardiovascular disease (body mass index, waist to hip ratio, systolic and diastolic blood pressure, consumption of fresh green vegetables, leisure time exercise, cigarette smoking and levels of social support) in two large cross sectional representative samples of the English population.
SUBJECTS—Men aged 20-64 years in the 1984 Health and Lifestyle Survey (excluding Scotland and Wales) first sweep and the 1993 Health Survey for England.
MAIN OUTCOME MEASURES—Mean values of continuous variables; age adjusted proportions of categorical variables; change in the relative index of inequality for each risk factor.
RESULTS—The overall prevalence of cardiovascular disease risk factors improved during the period in which cardiovascular disease mortality was falling. The social distribution of cardiovascular disease risk factors, in contrast, did not become more extreme. Increases in the relative index of inequality for angina from 1.75 to 1.86,( )for eating vegetables less than once a day from 1.76 in 1984 to 1.96 in 1993, and an apparently larger increase in inequality of social support, from 1.92 to 2.53 were not statistically significant. In most cases the degree of inequality in risk factors tended to narrow non-significantly: for example the relative index of inequality fell from 5.02 in 1984 to 3.07 in 1993 for systolic blood pressure, from 5.60 to 4.29 for current smoking and from 6.24 to 4.19 for eating other than wholemeal bread as the main form of bread in the diet. The two statistically significant changes in inequality were in the direction of narrowing inequality: from a relative index of inequality of 2.12 to 0.90 for diastolic blood pressure (p<0.01) and from 19.3 to 0.87 (p<0.01) for psychological distress as indicated by the General Health Questionnaire.
CONCLUSIONS—Healthier lifestyle options have not been adopted at a significantly faster rate by middle class than working class people over this time period. At the population level the change in risk factors is consistent with falling cardiovascular mortality. The change in the social distribution of risk factors within the population, however, shows little or no relation to the pattern of widening inequality in cardiovascular mortality. This may be because the effect is lagged, or because the adoption of healthier behaviour confers greater benefits on those in higher socioeconomic status groups.


Keywords: cardiovascular diseas