Dual-etalon, cavity-ring-down, frequency comb spectroscopy.

The 'dual etalon frequency comb spectrometer' is a novel low cost spectometer with limited moving parts. A broad band light source (pulsed laser, LED, lamp ...) is split into two beam paths. One travels through an etalon and a sample gas, while the second arm is just an etalon cavity, and the two beams are recombined onto a single detector. If the free spectral ranges (FSR) of the two cavities are not identical, the intensity pattern at the detector with consist of a series of heterodyne frequencies. Each mode out of the sample arm etalon with have a unique frequency in RF (radio-frequency) range, where modern electronics can easily record the signals. By monitoring these RF beat frequencies we can then determine when an optical frequencies is absorbed. The resolution is set by the FSR of the cavity, typically 10 MHz, with a bandwidth up to 100s of cm{sup -1}. In this report, the new spectrometer is described in detail and demonstration experiments on Iodine absorption are carried out. Further we discuss powerful potential next generation steps to developing this into a point sensor for monitoring combustion by-products, environmental pollutants, and warfare agents

Acoustic detector for fission neutrons.

Abstract Not Provide

Conversion of an Atomic Fermi Gas to a Long-Lived Molecular Bose Gas

We have converted an ultracold Fermi gas of $^6$Li atoms into an ultracold gas of $^6$Li$_2$ molecules by adiabatic passage through a Feshbach resonance. Approximately $1.5 \times 10^5$ molecules in the least-bound, $v = 38$, vibrational level of the X$^1 \Sigma ^+_g$ singlet state are produced with an efficiency of 50%. The molecules remain confined in an optical trap for times of up to 1 s before we dissociate them by a reverse adiabatic sweep.Comment: Accepted for publication in Phys. Rev. Letter

Formation and Propagation of Matter Wave Soliton Trains

Attraction between atoms in a Bose-Einstein-Condensate renders the condensate unstable to collapse. Confinement in an atom trap, however, can stabilize the condensate for a limited number of atoms, as was observed with 7Li, but beyond this number, the condensate collapses. Attractive condensates constrained to one-dimensional motion are predicted to form stable solitons for which the attractive interactions exactly compensate for the wave packet dispersion. Here we report the formation or bright solitons of 7Li atoms created in a quasi-1D optical trap. The solitons are created from a stable Bose-Einstein condensate by magnetically tuning the interactions from repulsive to attractive. We observe a soliton train, containing many solitons. The solitons are set in motion by offsetting the optical potential and are observed to propagate in the potential for many oscillatory cycles without spreading. Repulsive interactions between neighboring solitons are inferred from their motion

The bear in Eurasian plant names: Motivations and models

Ethnolinguistic studies are important for understanding an ethnic group's ideas on the world, expressed in its language. Comparing corresponding aspects of such knowledge might help clarify problems of origin for certain concepts and words, e.g. whether they form common heritage, have an independent origin, are borrowings, or calques. The current study was conducted on the material in Slavonic, Baltic, Germanic, Romance, Finno-Ugrian, Turkic and Albanian languages. The bear was chosen as being a large, dangerous animal, important in traditional culture, whose name is widely reflected in folk plant names. The phytonyms for comparison were mostly obtained from dictionaries and other publications, and supplemented with data from databases, the co-authors' field data, and archival sources (dialect and folklore materials). More than 1200 phytonym use records (combinations of a local name and a meaning) for 364 plant and fungal taxa were recorded to help find out the reasoning behind bear-nomination in various languages, as well as differences and similarities between the patterns among them. Among the most common taxa with bear-related phytonyms were Arctostaphylos uva-ursi (L.) Spreng., Heracleum sphondylium L., Acanthus mollis L., and Allium ursinum L., with Latin loan translation contributing a high proportion of the phytonyms. Some plants have many and various bear-related phytonyms, while others have only one or two bear names. Features like form and/or surface generated the richest pool of names, while such features as colour seemed to provoke rather few associations with bears. The unevenness of bear phytonyms in the chosen languages was not related to the size of the language nor the present occurence of the Brown Bear in the region. However, this may, at least to certain extent, be related to the amount of the historical ethnolinguistic research done on the selected languages

Tunable interaction in quantum degenerate lithium

We have designed and constructed an apparatus capable of simultaneously creating both a quantum degenerate Bose and Fermi gas of the two stable isotopes of lithium, 7Li and 6Li, respectively. This apparatus has the capability of optically confining pre-cooled samples of atoms, and applying an arbitrary magnetic bias field between zero and 1000 G. The optical confinement allows us to work with any spin state or mixture, of 6Li or 7Li. The applied external field can tune the atoms through atom-atom scattering resonances, known as Feshbach resonances. These resonance change the effective coupling between atoms, allowing us to study the behavior of the atoms in both the weak and strong coupling limits. With this tool we have been able to produce large lithium Bose-Einstein condensates, stable attractive Bose-Einstein condensates in one dimension, coherent Fermi mixtures, strongly interacting Fermi mixtures, and have induced the formation of bosonic molecules from an interacting Fermi mixture

Corrigendum: TerraceM-2: A Matlab® Interface for Mapping and Modeling Marine and Lacustrine Terraces

International audienceIn the original article, we neglected to include the funder German Israeli Foundation (GIF), Grant No. I-1280-301.8/2014 to MS.In addition, we neglected to include our colleagues Amotz Agnon and Yaniv Darvasi in the acknowledgments in the published article. The corrected Acknowledgments Statement appears below.We thank Peru Bilbao, Simone Racano, José-Miguel Martínez, Gino de Gelder, and Sedigheh Farahi for valuable suggestions and bug reports that helped improving TerraceM-2, and Marco Meschis for insights on the synchronous correlation method. The TerraceM-2 codes and scripts are included in the Supporting Information and available at www.terracem.com. We would also like to thank Prof. Amotz Agnon and Yaniv Darvasi from the Institute of Earth Sciences of the Hebrew University of Jerusalem that surveyed the drone topography in Israel and introduced the authors on the geology and geomorphology of the Dead Sea.The authors apologize for this error and state that this does not change the scientific conclusions of the article in any way. The original article has been updated

Accelerating Water Quality Improvements through Integrated Planning- Seattle\u27s Integrated Plan

The City of Seattle, Seattle Public Utilities (SPU), the U.S. Environmental Protection Agency (EPA), the U.S. Department of Justice (DOJ), and the Washington State Department of Ecology (ECY) negotiated a Consent Decree that establishes requirements for SPU’s Combined Sewer Overflow (CSO) Reduction Program. The Consent Decree allows SPU to propose an Integrated Plan for implementing stormwater control projects in addition to CSO control measures outlined in a Long Term Control Plan. Development of an Integrated Plan provided the opportunity to propose stormwater and CSO project actions, prioritized and sequenced in order to achieve greater benefits for water quality of the receiving waters in and around Seattle than would otherwise be achieved with CSO investments alone and result in these improvements happening sooner. Seattle is one of the first cities in the country to have the opportunity to demonstrate an integrated and prioritized program of stormwater and CSO projects as part of a Consent Decree under EPAs Integrated Planning framework. To develop the Integrated Plan, SPU first ranked its receiving water bodies based on the Consent Decree requirements. Next, SPU developed preliminary loads and cost estimates to identify potential stormwater projects to be implemented and CSO projects to be delayed. The CSO deferral candidates are detention projects while the candidate stormwater projects include a mix of green, gray, and programmatic measures. SPU developed pollutant loads models and conducted exposure assessments to compare the water quality, human health and habitat benefits of each stormwater and CSO project, as required by the Consent Decree. SPU used multi-objective decision analysis (MODA) to help select the combination of stormwater projects and CSO deferrals that meets the Consent Decree requirements and supports SPUs triple bottom line decision making-- financial, environmental and social impacts and benefits. SPU assembled an independent Expert Panel to review and help refine the analytical methods and provide feedback on the results. The expected results are a significant improvement in overall pollutant load reductions in a shorter time frame than would have occurred. The option to propose an Integrated Plan as part of the Long Term Control Plan is an exciting opportunity and SPU is well positioned to demonstrate the value of a more integrated approach for improved water quality that will result in larger improvements in wet weather discharges than would have occurred without the integrated approach. This paper will present an overview of the process, some of the technical challenges and how they were overcome, and the resulting integrated plan. It will also discuss how such integrated planning could be utilized by other communities to prioritize water quality improvements more cost-effectively in Puget Sound/Salish Sea