51 research outputs found
CMB-S4: Forecasting Constraints on Primordial Gravitational Waves
CMB-S4---the next-generation ground-based cosmic microwave background (CMB)
experiment---is set to significantly advance the sensitivity of CMB
measurements and enhance our understanding of the origin and evolution of the
Universe, from the highest energies at the dawn of time through the growth of
structure to the present day. Among the science cases pursued with CMB-S4, the
quest for detecting primordial gravitational waves is a central driver of the
experimental design. This work details the development of a forecasting
framework that includes a power-spectrum-based semi-analytic projection tool,
targeted explicitly towards optimizing constraints on the tensor-to-scalar
ratio, , in the presence of Galactic foregrounds and gravitational lensing
of the CMB. This framework is unique in its direct use of information from the
achieved performance of current Stage 2--3 CMB experiments to robustly forecast
the science reach of upcoming CMB-polarization endeavors. The methodology
allows for rapid iteration over experimental configurations and offers a
flexible way to optimize the design of future experiments given a desired
scientific goal. To form a closed-loop process, we couple this semi-analytic
tool with map-based validation studies, which allow for the injection of
additional complexity and verification of our forecasts with several
independent analysis methods. We document multiple rounds of forecasts for
CMB-S4 using this process and the resulting establishment of the current
reference design of the primordial gravitational-wave component of the Stage-4
experiment, optimized to achieve our science goals of detecting primordial
gravitational waves for at greater than , or, in the
absence of a detection, of reaching an upper limit of at CL.Comment: 24 pages, 8 figures, 9 tables, submitted to ApJ. arXiv admin note:
text overlap with arXiv:1907.0447
The Future Landscape of High-Redshift Galaxy Cluster Science
Large scale structure and cosmolog
CMB-S4
We describe the stage 4 cosmic microwave background ground-based experiment CMB-S4
CMB-S4: Forecasting Constraints on Primordial Gravitational Waves
Abstract: CMB-S4âthe next-generation ground-based cosmic microwave background (CMB) experimentâis set to significantly advance the sensitivity of CMB measurements and enhance our understanding of the origin and evolution of the universe. Among the science cases pursued with CMB-S4, the quest for detecting primordial gravitational waves is a central driver of the experimental design. This work details the development of a forecasting framework that includes a power-spectrum-based semianalytic projection tool, targeted explicitly toward optimizing constraints on the tensor-to-scalar ratio, r, in the presence of Galactic foregrounds and gravitational lensing of the CMB. This framework is unique in its direct use of information from the achieved performance of current Stage 2â3 CMB experiments to robustly forecast the science reach of upcoming CMB-polarization endeavors. The methodology allows for rapid iteration over experimental configurations and offers a flexible way to optimize the design of future experiments, given a desired scientific goal. To form a closed-loop process, we couple this semianalytic tool with map-based validation studies, which allow for the injection of additional complexity and verification of our forecasts with several independent analysis methods. We document multiple rounds of forecasts for CMB-S4 using this process and the resulting establishment of the current reference design of the primordial gravitational-wave component of the Stage-4 experiment, optimized to achieve our science goals of detecting primordial gravitational waves for r > 0.003 at greater than 5Ï, or in the absence of a detection, of reaching an upper limit of r < 0.001 at 95% CL
The Stages of Change in Smoking Cessation Among Smokers of Khorramabad
Introduction: Improper lifestyle is one of the factors affecting the incidence of chronic diseases. According to the World Health Organization statistics, smoking causes four million deaths annually. Studies show that in 1993, 28.6% men and 3.6% of women older than 15 years in the country were smokers. The most practical stage behavior change model is Transtheoretical model. Therefore, this study used this model. Methods: This cross-sectional study was done on 200 smokers or ex- smokers of Khorramabad who had high school diploma or higher educational levels. Cluster sampling was conducted in two stages. Data was collected by a questionnaire whose validity and reliability had been approved. Data was analyzed by using SPSS statistical software 11.5 and descriptive statistics. P level <0.05 was considered as significant. Results: Mean age was 42.5±7.85 years. Regarding stages of change, 39.5% were in pre-contemplation stage, 25.5% in contemplation stage, 12% in preparation stage, 5.5% in action stage and 17.5% were in maintenance stage. Variables that had a significant relationship with stages of change included years of smoking (p=0.001), complications of smoking (0.000), and age (p=0.04). There was no significant relationship between marital status, education, family and income, and stages of change. Conclusion: In this study, majority of the population under study were in the early stages. It is therefore necessary to provide educational programs and develop strategies for the same. Due to the significant relationship between age and years of smoking and exposure to advanced stages of change, people should be made aware of the problems of smoking earlier so that they can decide as soon as possible about smoking cessation
Effects of boosting on extragalactic components: methods and statistical studies
In this work, we examine the impact of our motion with respect to the Cosmic Microwave Background (CMB) rest frame on statistics of CMB maps by examining the one-, two-, three-, and four- point statistics of simulated maps of the CMB and SunyaevâZeldovich (SZ) effects. We validate boosting codes by comparing their outcomes for temperature and polarization power spectra up to â â 6000. We derive and validate a new analytical formula for the computation of the boosted power spectrum of a signal with a generic frequency dependence. As an example we show how this increases the boosting correction to the power spectrum of CMB intensity measurements by âŒ30 per cent at 150 GHz. We examine the effect of boosting on thermal and kinetic SZ power spectra from semianalytical and hydrodynamical simulations; the boosting correction is generally small for both simulations, except when considering frequencies near the tSZ null. For the non-Gaussian statistics, in general we find that boosting has no impact with two exceptions. We find that, whilst the statistics of the CMB convergence field are unaffected, quadratic estimators that are used to measure this field can become biased at the O(1) per cent level by boosting effects. We present a simple modification to the standard estimators that removes this bias. Second, bispectrum estimators can receive a systematic bias from the Doppler induced quadrupole when there is anisotropy in the sky â in practice this anisotropy comes from masking and inhomogeneous noise. This effect is unobservable and already removed by existing analysis methods
Development of an electrochemical nanosensor for the determination of gallic acid in food
In the present work, a silver nanoparticle/delphinidin modified glassy carbon electrode (AgNP/Delph/GCE) was fabricated as a highly sensitive electrochemical sensor for gallic acid (GA) determination. Cyclic voltammetry experiments indicated a higher sensitivity and better selectivity for gallic acid when using the AgNP/Delph/GCE as compared with the bare GCE surface, which were attributed to AgNPs and delphinidin, respectively. Moreover, the calculated surface electron transfer rate constant (ks), and the electron transfer coefficient (\u3b1) between the GCE and the electrodeposited delphinidin demonstrated that delphinidin is an excellent electron transfer mediator for the electrocatalytic process. The average catalytic rate constant (k\u2032) of the overall process was also estimated to be 7.40
7 10-4 cm s-1 for the AgNP/Delph/GCE in the presence of 1.50 mmol L-1 of GA. Amperometry experiments were used to determine the limit of detection of the AgNP/Delph/GCE electrochemical sensor, which was 0.28 \u3bcmol L-1 of GA. Finally, two linear ranges were found, i.e. 0.60-8.68 \u3bcmol L-1 and 8.68-625.80 \u3bcmol L-1 for GA. The activity of the modified electrode was eventually investigated to assess the potential quantification of GA in real foods
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