3,263 research outputs found
Dual-color magic-wavelength trap for suppression of light shifts in atoms
No full textWe present an optical approach to compensating for spatially varying ac-Stark shifts that appear on atomic ensembles subject to strong optical control or trapping fields. The introduction of an additional weak light field produces an intentional perturbation between atomic states that is tuned to suppress the influence of the strong field. The compensation field suppresses sensitivity in one of the transition frequencies of the trapped atoms to both the atomic distribution and motion. We demonstrate this technique in a cold rubidium ensemble and show a reduction in inhomogeneous broadening in the trap. This two-color approach emulates the magic-trapping approach that is used in modern atomic-lattice clocks but provides greater flexibility in choice of atomic species, probe transition, and trap wavelength.A.P. Hilton, C. Perrella, A.N. Luiten, and P.S. Ligh
J.F. Siedo examines lot owned by P.S. Wear
No full textA detailed checkup on fire hazards through the city is being conducted by the municipal fire prevention bureau. J.F. Siedo, left, examines lot owned by P.S. Wear, right. Photograph also shows outdoor advertisement for Pearl beer
Mt. Borah
No full textA mountain rises above some wooded foothills. Description reads: ""Telephoto view of Mt. Borah (12,655 ft. elevation) highest mountain in Idaho, taken from Grazing Service CCC Camp Chilly #111. Forest: Challis, State: Idaho, Date: 7/1940, Author: P.S. Bieler""
Spectral broadening of a single-photon transition in the evanescent field of an exposed-core fiber
No full textWe theoretically and experimentally examine the spectroscopy of warm atoms traversing the evanescent field of a guided mode in silica glass. The subwavelength scale of the evanescent field leads to a large spectral broadening dominated by transit-time dephasing, creating a lineshape quite different from that of atoms in free space, and also distinct from that arising from transit-time-limited interactions in a field with a Gaussian intensity profile. We show reasonable agreement between our modeling of this scenario and experimental D2-line spectra obtained from an exposed-core fiber immersed in rubidium vapor.H.P. Griesser, C. Perrella, P.S. Light and A.N. Luite
Observation of electromagnetically induced transparency (EIT) in Rb-filled hollow-core fibre
No full textAbstract not availableT.M. Stace, C. Perrella, P.S. Light, F. Benabid, A.N. Luite
Hyndman Peak
No full textA mountain is visible across a valley and between two hills. Description reads: ""Hyndman Peak (12,078 ft. elevation) as seen from upper Big Lost River near Kane Creek on Forest Road to Ketchum. Forest: Challis, State: Idaho, Date: 7/1940, Author: P.S. Bieler""
A comparison of six and 12 PUVA treatments in the prophylaxis of polymorphic light eruption
No full textPolymorphic light eruption (PLE) is a common condition for which the most effective treatment is prophylactic phototherapy. This is traditionally given in courses of approximately 12–15 exposures. We compared the effect of six and 12 treatments of psoralen-UVA (PUVA) therapy, in the prophylaxis of PLE, in a side-to-side within-patient comparison pilot study. In six out of eight patients, six treatments provided as much protection as 12 treatments. Five of these six patients had reported relatively mild disease in the previous year, in comparison to the other two patients. In view of the inconvenience and increased incidence of adverse effects associated with long treatment courses, we recommend the use of short courses, particularly in patients who are relatively mildly affected
Light-shift spectroscopy of optically trapped atomic ensembles
No full textWe develop a method for extracting the physical parameters of interest for a conventional dipole-trapped cold atomic ensemble. This technique uses the spatially dependent ac-Stark shift of the trap itself to project the atomic distribution onto a light-shift broadened transmission spectrum. We develop a model that connects the atomic distribution with the expected transmission spectrum. We then demonstrate the utility of the technique by deriving the temperature, trap depth, lifetime, and trapped atom number from data that was taken in a single shot experimental measurement.Ashby P Hilton, Andre N Luiten and Philip S Ligh
Response of migrating Chinook salmon (Oncorhynchus tshawytscha) smolts to in-stream structure associated with culverts. [In special issue: Riverine Hydroecology: Advances in Research and Applications. Selected Papers from the Tenth International Symposium on Regulated Streams, Stirling, August 2006]
No full textPoorly designed culverts can impede upstream movements of fish under high flows when excessive water velocities create adverse conditions. Improvement in upstream fish passage efficiency may occur with placement of structures within culverts that increase hydraulic complexity and provide resting areas. The effects of structural modification on downstream migrants, however, are unknown. To address this gap in knowledge, the behaviour of Chinook salmon (Oncorhynchus tshawytscha) smolts was assessed in an experimental laboratory flume. Under light and dark conditions, fish were observed as they encountered either an unmodified aluminium channel (control) or one of two treatments: an intermediate substrate (treatment channel lined with corrugated sheet) or a complex substrate (addition of cobbles to the intermediate treatment). More smolts passed the control channel than the treatment channels. Even with control of the variation in flow between channels, under light conditions more fish than expected passed the control channel when paired with the complex treatment. Smolts more frequently rejected both treatments than the control channel when light, and the complex treatment when dark, by swimming upstream against the flow after entry. The majority of fish moved through the flume facing downstream, although a greater proportion faced upstream when dark than when light, and entered the control channel. Velocity of downstream movement (ground velocity) was greater through the control channel than for the treatment routes, and slower than the mean water velocity, and under the dark condition. When mean water velocities were taken into account, the net velocity through the control channel was not significantly different to the intermediate, and lower than the complex channel. Juvenile Chinook salmon determined fine-scale variation in structural complexity and exhibited avoidance behaviour in the presence and absence of visual stimuli. Hydraulic stimuli influenced route selection exhibited by migratory juvenile salmonids
Author Correction: New perspectives on Neanderthal dispersal and turnover from Stajnia Cave (Poland)
No full textThe Author contributions section now reads:“W.N., A.N. and S.T. designed research; A.P., M.H., W.N., S.B., M.U., A.M., H.F., M.D.B., P.S., K.S., M.Ż., A.W., A.N. and S.T. performed research; A.P., M.H., W.N., S.B., M.U., A.M., H.F., M.D.B., P.S., K.S., M.Ż., A.W., A.N. and S.T. analysed data; A.P., M.H., S.T., W.N. and S.B. wrote the paper with the collaboration of all the co-authors.
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