相关论文: Gas temperature measurement based on contrast reve…
A novel inversion technique is proposed to compute parametric maps showing the temperature, density and chemical composition of cosmic hot gas from X-ray hyper-spectral images. The parameters are recovered by constructing a unique…
We report on a new optical implementation of primary gas thermometry based on laser absorption spectrometry in the near infrared. The method consists in retrieving the Doppler broadening from highly accurate observations of the line shape…
We show that thermalization of the motion of atoms at negative temperature is possible in an optical lattice, for conditions that are feasible in current experiments. We present a method for reversibly inverting the temperature of a trapped…
We present a new method for recovering the kinetic temperature of the intervening diffuse gas to an accuracy of 10%. The method is based on the comparison of unsaturated absorption-line profiles of two species with different atomic weights.…
Carbon dioxide is a vital gas for life on Earth, a waste product of human activities, and widely used in agriculture and industry. Its accurate sensing is therefore of great interest. Optical sensors exploiting the mid-infrared light…
This manuscript presents an ultrafast-laser-absorption-spectroscopy (ULAS) diagnostic capable of providing calibration-free, single-shot measurements of temperature and CO at 5 kHz in combustion gases at low and high pressures. A detailed…
We introduce an absorption imaging technique for ultracold gases that suppresses interference fringes and coherence-induced artifacts by reducing the transverse spatial coherence of the imaging light. The method preserves the narrow…
Passive hyperspectral longwave infrared measurements are remarkably informative about the surroundings. Remote object material and temperature determine the spectrum of thermal radiance, and range, air temperature, and gas concentrations…
This work developed an accurate and robust absorption-based method for spatially resolved measurements of gas temperatures in flames and reacting flows, with typical single-measurement uncertainties on the order of 1\%. This method exploits…
We introduce a spectroscopic approach to primary gas thermometry, harnessing precise optical cavity resonance frequencies and ab initio molecular line intensity calculations. By utilizing CO (3-0) vibrational band lines and cavity mode…
We present an optical aberration correction technique for ultracold quantum gas experiments which directly utilizes the quantum gas as a wavefront sensor. The direct use of the quantum gas enables correcting aberrations that are otherwise…
Absorption imaging with quasi-resonant laser light is a commonly used technique to probe ultra-cold atomic gases in various geometries. Here we investigate some non-trivial aspects of this method when it is applied to in situ diagnosis of a…
Carbon monoxide (CO) is a significant indicator gas with considerable application value in atmospheric monitoring, industrial production and medical diagnosis. Its fundamental vibrational band locates around 4.6 $\upmu$m and has larger…
Femtosecond coherent multidimensional spectroscopy is demonstrated for an ultracold gas. For this, a setup for phase modulation spectroscopy is used to probe the $3^2\mathrm{S}_{1/2} - 2^2\mathrm{P}_{1/2, 3/2}$ transition in an 800…
Time-resolved spectroscopic temperature measurements of a sealed carbon dioxide sample cell were realized with an optical frequency comb combined with a two-dimensional dispersive spectrometer. A supercontinuum laser source based on an…
Medium and high resolution spectroscopy of U Equulei from 1 to 4 microns during 1997-2003 has revealed information about its unusual circumstellar envelope, observed previously at optical and radio wavelengths. Strong absorption bands of…
We have investigated the fluorescence emission in the Near Infrared from the air and its main components, nitrogen and oxygen. The gas was excited by a 95kV electron beam and the fluorescence light detected by an InGaAs photodiode,…
The global climate change calls for a more environmental friendly use of energy and has led to stricter limits and regulations for the emissions of various greenhouse gases. Consequently, there is nowadays an increasing need for the…
We introduce a technique based on infrared thermal emission, termed depth thermography, that can remotely measure the temperature distribution beneath the surface of certain objects. Depth thermography utilizes the thermal-emission spectrum…
The material eroded from the surface of plasma facing components is redeposited partly close to high heat flux areas. At these locations, the deposit is heated by the plasma and the deposition pattern evolves depending on the operation…