scholarly journals Cavity buildup dispersion spectroscopy

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Agata Cygan ◽  
Adam J. Fleisher ◽  
Roman Ciuryło ◽  
Keith A. Gillis ◽  
Joseph T. Hodges ◽  
...  
Keyword(s):  
Laser Scanning ◽  
New Records ◽  
Laser Excitation ◽  
Frequency Standard ◽  
Cavity Resonance ◽  
Single Shot ◽  
Resonant Laser ◽  
Measurement Duration ◽  
Fundamental Research ◽  
Remotely Sense

AbstractMeasurements of ultrahigh-fidelity absorption spectra can help validate quantum theory, engineer ultracold chemistry, and remotely sense atmospheres. Recent achievements in cavity-enhanced spectroscopy using either frequency-based dispersion or time-based absorption approaches have set new records for accuracy with uncertainties at the sub-per-mil level. However, laser scanning or susceptibility to nonlinearities limits their ultimate performance. Here we present cavity buildup dispersion spectroscopy (CBDS), probing the CO molecule as an example, in which the dispersive frequency shift of a cavity resonance is encoded in the cavity’s transient response to a phase-locked non-resonant laser excitation. Beating between optical frequencies during buildup exactly localizes detuning from mode center, and thus enables single-shot dispersion measurements. CBDS can yield an accuracy limited by the chosen frequency standard and measurement duration and is currently 50 times less susceptible to detection nonlinearity compared to intensity-based methods. Moreover, CBDS is significantly faster than previous frequency-based cavity-enhanced methods. The generality of CBDS shows promise for improving fundamental research into a variety of light–matter interactions.

scholarly journals Tardigrades of Kristianstads Vattenrike Biosphere Reserve with description of four new species from Sweden

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Edoardo Massa ◽  
Roberto Guidetti ◽  
Michele Cesari ◽  
Lorena Rebecchi ◽  
K. Ingemar Jönsson
Keyword(s):  
New Species ◽  
Laser Scanning ◽  
New Records ◽  
Biosphere Reserve ◽  
Morphological Characters ◽  
Sem Analysis ◽  
Morphological Data ◽  
Integrative Approach ◽  
Confocal Laser ◽  
Biological Value

AbstractKristianstads Vattenrike Biosphere Reserve [KVBR] is a UNESCO designated area of Sweden possessing high biological value. Although several studies on tardigrades inhabiting Sweden have been performed, the KVBR area has been neglected. The current study investigates the tardigrade fauna of five areas of the biosphere reserve and includes 34 samples of different substrates analysed quantitatively and qualitatively. In total, 33 species of tardigrades were found in the samples, including 22 new records for the Skåne region, 15 new records for Sweden, and four species new to science. Mesobiotus emiliae sp. nov., Xerobiotus gretae sp. nov., Itaquascon magnussoni sp. nov., and Thulinius gustavi sp. nov. were described with an integrative approach (when possible) using morphological characters (light, electron scanning, and confocal laser scanning microscopies) and molecular markers (ITS2, 18S, 28S, cox1). A new protocol to increase morphological data was developed recovering mounted specimens within old slides for SEM analysis. Emended diagnoses for the genus Itaquascon and the transfer of Platicrista itaquasconoide to the genus Meplitumen are proposed. This study enriches the knowledge of the tardigrade biodiversity both within the KVBR and in Sweden and contributes to the rapidly increasing number of tardigrade species reported worldwide. The 33 species identified in the KVBR area represents 28% of all water bear species found in Sweden so far. The restricted study areas and limited number of samples collected suggests that the KVBR is very rich of tardigrades.

Resonant laser excitation of uranium with a pulsed laser

1984 ◽  
Vol 17 (15) ◽  
pp. 3083-3090 ◽  
Author(s):  
M A Lauder ◽  
P T Greenland
Keyword(s):  
Laser Excitation ◽  
Pulsed Laser ◽  
Resonant Laser

Theoretical modeling of resonant laser excitation of atoms in a magnetic field

2008 ◽  
Vol 77 (1) ◽  
Author(s):  
Andrew James Murray ◽  
William MacGillivray ◽  
Martyn Hussey
Keyword(s):  
Magnetic Field ◽  
Laser Excitation ◽  
Theoretical Modeling ◽  
Resonant Laser

Quantitative Laser Scanning Confocal Autofluorescence Microscopy (Lscam) of Normal and Premalignant Colonic Tissues

1997 ◽  
Vol 3 (S2) ◽  
pp. 25-26
Author(s):  
Hsing-Wen Wang ◽  
Joseph Willis ◽  
Michael V. Sivak ◽  
Joseph A. Izatt
Keyword(s):  
Laser Scanning ◽  
Laser Excitation ◽  
Argon Laser ◽  
Confocal Imaging ◽  
Premalignant Lesions ◽  
Tubular Adenoma ◽  
Normal Colon ◽  
Ultraviolet Excitation ◽  
Lif Spectroscopy

Laser-induced fluorescence (LIF) spectroscopy of tissues has been proposed as an adjunct to endoscopy for in vivo gastrointestinal (GI) diagnosis of premalignant lesions. In previous studies, under ultraviolet excitation (350-370 nm), sources of LIF signal differences in normal, and premalignant colonie tissues have been identified including 1) changes in gross tissue morphology, 2) increased hemoglobin absorption in adenomatous tissues, and 3) increased red fluorescence in dysplastic cells. However, many questions remain regarding the specific origins and biochemical correlates of GI tissue autofluorescence.We report on a study of quantitative ultraviolet LIF spectral microscopy in human colonic tissues using a laser scanning confocal microscope with argon laser excitation 351-364 nm. Frozen sections (6μm) of normal colon (n=10) and tubular adenoma (n=8) were prepared from fresh surgical resection specimens using a previously published protocol. To identify histological components accurately, LSCAM slides were alcohol fixed and H&E histologically stained following confocal imaging.

Observation of fluorescence from high-lying states of potassium in a sodium-potassium mixture upon resonant laser excitation

1981 ◽  
Vol 36 (6) ◽  
pp. 449-452 ◽  
Author(s):  
M. Allegrini ◽  
P. Bicchi ◽  
S. Gozzini ◽  
P. Savino
Keyword(s):  
Laser Excitation ◽  
Sodium Potassium ◽  
Resonant Laser

Photoluminescence and decay kinetics of indirect free excitons in diamonds under the near-resonant laser excitation

1996 ◽  
Vol 99 (11) ◽  
pp. 793-797 ◽  
Author(s):  
K. Takiyama ◽  
M.I. Abd-Elrahman ◽  
T. Fujita ◽  
T. Oda
Keyword(s):  
Laser Excitation ◽  
Decay Kinetics ◽  
Resonant Laser ◽  
Kinetics Of

scholarly journals CAN WE USE LOW-COST 360 DEGREE CAMERAS TO CREATE ACCURATE 3D MODELS?

2018 ◽  
Vol XLII-2 ◽  
pp. 69-75 ◽  
Author(s):  
L. Barazzetti ◽  
M. Previtali ◽  
F. Roncoroni
Keyword(s):  
Laser Scanning ◽  
Low Cost ◽  
Point Clouds ◽  
3D Models ◽  
Bundle Adjustment ◽  
Field Of View ◽  
Large Field ◽  
Single Shot ◽  
New Paradigm ◽  
Image Orientation

360 degree cameras capture the whole scene around a photographer in a single shot. Cheap 360 cameras are a new paradigm in photogrammetry. The camera can be pointed to any direction, and the large field of view reduces the number of photographs. This paper aims to show that accurate metric reconstructions can be achieved with affordable sensors (less than 300 euro). The camera used in this work is the Xiaomi Mijia Mi Sphere 360, which has a cost of about 300 USD (January 2018). Experiments demonstrate that millimeter-level accuracy can be obtained during the image orientation and surface reconstruction steps, in which the solution from 360° images was compared to check points measured with a total station and laser scanning point clouds. The paper will summarize some practical rules for image acquisition as well as the importance of ground control points to remove possible deformations of the network during bundle adjustment, especially for long sequences with unfavorable geometry. The generation of orthophotos from images having a 360° field of view (that captures the entire scene around the camera) is discussed. Finally, the paper illustrates some case studies where the use of a 360° camera could be a better choice than a project based on central perspective cameras. Basically, 360° cameras become very useful in the survey of long and narrow spaces, as well as interior areas like small rooms.

scholarly journals Single shot laser ablation MC-ICP-MS for depth profile analysis of U isotopes in UO2 single crystals

2019 ◽  
Vol 34 (10) ◽  
pp. 1965-1974 ◽  
Author(s):  
M. Krachler ◽  
A. Bulgheroni ◽  
A. I. Martinez Ferri ◽  
Y. Ma ◽  
A. Miard ◽  
...  
Keyword(s):  
Single Crystals ◽  
Laser Scanning ◽  
Focused Ion Beam ◽  
Profile Analysis ◽  
Ion Beam ◽  
Depth Profiling ◽  
Confocal Laser ◽  
Single Shot ◽  
Dual Beam ◽  
Icp Ms

Depth profiling of the n(235U)/n(238U) amount ratio in UO2 single crystals employing LA-MC-ICP-MS, a dual beam focused ion beam and confocal laser scanning profilometry.

Sign in / Sign up

Export Citation Format

Share Document