High-power, low-phase-noise, frequency-agile laser system for delivering fiber-noise-cancelled pulses for Strontium clock atom interferometry

We present the development of a laser system for performing single-photon atom interferometry on the 698 nm clock transition in ultracold Strontium. We coherently combine the power of two Titanium:Sapphire lasers and demonstrate chirps of 200 MHz in 2.5 ms while phase-locked to an optical reference. Moreover, we demonstrate a novel scheme to deliver 4 W pulsed beams to the atoms via a mode-cleaning optical fiber using active noise cancellation.Comment: 5 pages, 3 figure

Learning curve analysis of thoracic endovascular aortic repair in relation to credentialing guidelines

ObjectiveRecently, practice guideline documents have recommended the completion of different levels of interventional experience and 5 or 10 thoracic endovascular aortic cases prior to surgeon credentialing. This study’s purpose was to determine whether these requirements are valid by reviewing three surgeons’ learning curves with thoracic aortic endovascular repairs.MethodsBetween 1998 and 2006, 67 patients underwent emergent or elective endovascular repair of thoracic aortic pathologies by one of three vascular surgeons with extensive experience with catheter manipulation and abdominal aortic endografts. Following standard retrospective review, each surgeon’s learning curve was analyzed using the cumulative sum failure method with a target success rate of 95% derived from the literature. The main outcome variable was primary technical success.ResultsThese 67 patients presented with several pathologies including elective (n = 31) and ruptured (n = 11) thoracic aortic aneurysms, acute dissections or aortic ulcers (n = 10), and acute blunt thoracic aortic trauma (n = 15). The mean age was 65 (range: 20 to 90) and the early (30 day) mortality rate was 19.4% in urgent cases (n = 36) and 0% in elective cases (n = 31). Paraplegia occurred in two patients (3%). Primary technical success was achieved in 62 cases (92.5%) and did not differ between surgeons (92.6%, 91.3%, 94.1%, respectively; P = .9). Each surgeon’s cases were plotted sequentially and the resulting learning curves were similar. Although acceptable outcomes were obtained throughout the study period, improved results, compared with the target success rate, were not achieved until each surgeon treated 5 to 10 patients.ConclusionThis study supports the case volume requirements of the Society for Vascular Surgery credentialing guidelines, which also requires extensive catheter and guidewire experience. With this background in catheter manipulation and endovascular abdominal aortic repair, surgeons can achieve optimal outcomes with thoracic aortic lesions following 5 to 10 cases

Towards More Precise Survey Photometry for PanSTARRS and LSST: Measuring Directly the Optical Transmission Spectrum of the Atmosphere

Motivated by the recognition that variation in the optical transmission of the atmosphere is probably the main limitation to the precision of ground-based CCD measurements of celestial fluxes, we review the physical processes that attenuate the passage of light through the Earth's atmosphere. The next generation of astronomical surveys, such as PanSTARRS and LSST, will greatly benefit from dedicated apparatus to obtain atmospheric transmission data that can be associated with each survey image. We review and compare various approaches to this measurement problem, including photometry, spectroscopy, and LIDAR. In conjunction with careful measurements of instrumental throughput, atmospheric transmission measurements should allow next-generation imaging surveys to produce photometry of unprecedented precision. Our primary concerns are the real-time determination of aerosol scattering and absorption by water along the line of sight, both of which can vary over the course of a night's observations.Comment: 41 pages, 14 figures. Accepted PAS

Matter-wave Atomic Gradiometer Interferometric Sensor (MAGIS-100)

MAGIS-100 is a next-generation quantum sensor under construction at Fermilab that aims to explore fundamental physics with atom interferometry over a 100-meter baseline. This novel detector will search for ultralight dark matter, test quantum mechanics in new regimes, and serve as a technology pathfinder for future gravitational wave detectors in a previously unexplored frequency band. It combines techniques demonstrated in state-of-the-art 10-meter-scale atom interferometers with the latest technological advances of the world's best atomic clocks. MAGIS-100 will provide a development platform for a future kilometer-scale detector that would be sufficiently sensitive to detect gravitational waves from known sources. Here we present the science case for the MAGIS concept, review the operating principles of the detector, describe the instrument design, and study the detector systematics.Comment: 65 pages, 18 figure

Links Among Gender, Inhibition, and Parental Socialization in the Development of Prosocial Behavior

Prosocial behavior encompasses sympathetic, helpful, and caring responses toward others. Temperamental characteristics and experiences of child rearing are associated with children’s prosocial behavior. However, little research has examined the associations between prosocial behavior and either temperamental inhibition or paternal child rearing. This study examined the contributions of maternal and paternal parenting and inhibition at 2 years to displays of prosocial behavior toward mothers and unfamiliar adults by 46 male and 42 female preschoolers. There were no direct links between toddler inhibition or fathers’ parenting and prosocial behavior 2 years later, although protective maternal parenting predicted prosocial behavior. Toddlers’ inhibition and gender moderated the links between maternal parenting and prosocial behavior. Maternal parenting was most strongly predictive of the prosocial behavior of more highly inhibited girls, suggesting there may be temperament- and gender-specific pathways for the development of positive characteristics

Supplementary document for High-power, low-phase-noise, frequency-agile laser system for delivering fiber-noise-cancelled pulses for Strontium clock atom interferometry - 6480548.pdf

Supplement 1. To facilitate reproduction of the results presented in the main text, this supplemental document provides further details on the experimental setup, including component part numbers

Microbial Water Quality Conditions Associated with Livestock Grazing, Recreation, and Rural Residences in Mixed-Use Landscapes

Contamination of surface waters with microbial pollutants from fecal sources is a significant human health issue. Identification of relative fecal inputs from the mosaic of potential sources common in rural watersheds is essential to effectively develop and deploy mitigation strategies. We conducted a cross-sectional longitudinal survey of fecal indicator bacteria (FIB) concentrations associated with extensive livestock grazing, recreation, and rural residences in three rural, mountainous watersheds in California, USA during critical summer flow conditions. Overall, we found that 86% to 87% of 77 stream sample sites across the study area were below contemporary Escherichia coli-based microbial water quality standards. FIB concentrations were lowest at recreation sites, followed closely by extensive livestock grazing sites. Elevated concentrations and exceedance of water quality standards were highest at sites associated with rural residences, and at intermittently flowing stream sites. Compared to national and state recommended E. coli-based water quality standards, antiquated rural regional policies based on fecal coliform concentrations overestimated potential fecal contamination by as much as four orders of magnitude in this landscape, hindering the identification of the most likely fecal sources and thus the efficient targeting of mitigation practices to address them

ARCSECOND RESOLUTION MAPPING OF SULFUR DIOXIDE EMISSION IN THE CIRCUMSTELLAR ENVELOPE OF VY CANIS MAJORIS

We report Submillimeter Array observations of SO[subscript 2] emission in the circumstellar envelope (CSE) of the red supergiant VY Canis Majoris, with an angular resolution of ≈1''. SO[subscript 2] emission appears in three distinct outflow regions surrounding the central continuum peak emission that is spatially unresolved. No bipolar structure is noted in the sources. A fourth source of SO[subscript 2] is identified as a spherical wind centered at the systemic velocity. We estimate the SO[subscript 2] column density and rotational temperature assuming local thermal equilibrium (LTE) as well as perform non-LTE radiative transfer analysis using RADEX. Column densities of SO[subscript 2] are found to be ~10[superscript 16] cm[superscript –2] in the outflows and in the spherical wind. Comparison with existing maps of the two parent species OH and SO shows the SO2 distribution to be consistent with that of OH. The abundance ratio [fSO[subscript 2] over fSO] is greater than unity for all radii larger than 3 × 10[superscript 16] cm. SO[subscript 2] is distributed in fragmented clumps compared to SO, PN, and SiS molecules. These observations lend support to specific models of circumstellar chemistry that predict [fSO[subscript 2] over fSO] > 1 and may suggest the role of localized effects such as shocks in the production of SO2 in the CSE