Related Experiment Video
Updated: May 11, 2026
08:22
Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization
Published on: August 6, 2018
Atmospheric Raman depolarization-ratio measurements
Applied Optics
|October 12, 2010
Summary
This study measures the nitrogen Raman depolarization ratio using lidar. Findings reveal how multiple scattering impacts lidar profiles of cloud parameters.
Area of Science:
- Atmospheric Science
- Remote Sensing
- Spectroscopy
Background:
- Accurate cloud parameter retrieval is crucial for climate modeling.
- Lidar technology offers vertical atmospheric profiling capabilities.
- Multiple scattering effects can introduce significant errors in lidar measurements.
Purpose of the Study:
- To investigate the influence of multiple scattering on lidar-derived cloud parameters.
- To quantify the impact of multiple scattering on the nitrogen Raman depolarization ratio.
- To improve the accuracy of lidar-based atmospheric measurements.
Main Methods:
- Utilizing a lidar system to measure the nitrogen Raman depolarization ratio.
- Analyzing lidar backscatter signals to assess multiple scattering effects.
- Comparing single and multiple scattering contributions to the depolarization ratio.
Main Results:
- Multiple scattering significantly affects the lidar profile of cloud parameters.
- The nitrogen Raman depolarization ratio is sensitive to multiple scattering.
- Quantified the extent of deviation in cloud parameters due to multiple scattering.
Conclusions:
- Multiple scattering must be accounted for in lidar cloud remote sensing.
- The nitrogen Raman depolarization ratio serves as an indicator of multiple scattering.
- Improved understanding enhances the reliability of lidar for atmospheric studies.
Related Concept Videos
01:20¹³C NMR: Distortionless Enhancement by Polarization Transfer (DEPT)
When proton-coupled carbon-13 spectra are simplified by a broadband proton decoupling technique, structural information about the coupled protons is lost. Distortionless enhancement by polarization transfer (DEPT) is a technique that provides information on the number of hydrogens attached to each carbon in a molecule. While the DEPT experiment utilizes complex pulse sequences, the pulse delay and flip angle are specifically manipulated. The resulting signals have different phases depending on...
01:04¹³C NMR: ¹H–¹³C Decoupling
The probability of having two carbon-13 atoms next to each other is negligible because of the low natural abundance of carbon-13. Consequently, peak splitting due to carbon-carbon spin-spin coupling is not observed in spectra. However, protons up to three sigma bonds away split the carbon signal according to the n+1 rule, resulting in complicated spectra.
A broadband decoupling technique is used to simplify these complex, sometimes overlapping, signals. Broadband decoupling relies on a...
A broadband decoupling technique is used to simplify these complex, sometimes overlapping, signals. Broadband decoupling relies on a...
01:20Raman Spectroscopy: Overview
The underlying principle of Raman spectroscopy is based on the interaction between light and matter, specifically molecules' inelastic scattering of photons. When a monochromatic beam of light, typically from a laser source, interacts with a sample, most scattered light has the same frequency as the incident light. This is known as Rayleigh scattering.
However, a small fraction of the scattered light exhibits a frequency shift due to the exchange of energy between the incident photons and the...
However, a small fraction of the scattered light exhibits a frequency shift due to the exchange of energy between the incident photons and the...
01:26Raman Spectroscopy Instrumentation: Overview
A conventional Raman spectrophotometer includes a laser source, a sample holding system, a wavelength selector, and a detector.
The monochromatic laser source, typically using visible or near-infrared radiation, generates a highly focused beam of light. This light interacts with the molecules of the sample, scattering some of the light. Liquid and gaseous samples are usually tested in ordinary glass capillaries, while solids can be analyzed as powders packed in capillaries or as potassium...
The monochromatic laser source, typically using visible or near-infrared radiation, generates a highly focused beam of light. This light interacts with the molecules of the sample, scattering some of the light. Liquid and gaseous samples are usually tested in ordinary glass capillaries, while solids can be analyzed as powders packed in capillaries or as potassium...
01:12Double Resonance Techniques: Overview
Double resonance techniques in Nuclear Magnetic Resonance (NMR) spectroscopy involve the simultaneous application of two different frequencies or radiofrequency pulses to manipulate and observe two distinct nuclear spins. One important application of double resonance is spin decoupling, which selectively suppresses coupling with one type of nucleus while observing the NMR signal from another nucleus, simplifying the spectrum and enhancing resolution.
Spin decoupling is usually achieved by...
Spin decoupling is usually achieved by...