Achromatic optical device for generation of a broadband frequency spectrum with high-frequency stability and sharp termination

2001 ◽  
Vol 18 (3) ◽  
pp. 335 ◽  
Author(s):  
S. N. Atutov ◽  
W. Baldini ◽  
R. Calabrese ◽  
V. Guidi ◽  
P. Lenisa ◽  
...  
Keyword(s):  
Frequency Spectrum ◽  
High Frequency ◽  
Frequency Stability ◽  
Optical Device ◽  
Broadband Frequency

Preferential acceleration of heavy ions from thermal velocities

1968 ◽  
Vol 46 (10) ◽  
pp. S638-S641 ◽  
Author(s):  
D. B. Melrose
Keyword(s):  
Frequency Spectrum ◽  
High Frequency ◽  
Heavy Ions ◽  
Crab Nebula ◽  
Low Frequency ◽  
High Frequency Waves ◽  
Hydromagnetic Waves ◽  
The Crab Nebula ◽  
Low Frequency Waves

The acceleration of ions from thermal velocities is analyzed to determine conditions under which heavy ions can be preferentially accelerated. Two accelerating mechanisms involving high-and low-frequency hydromagnetic waves respectively are considered. Preferential acceleration of heavy ions occurs for high-frequency waves if the frequency spectrum falls off faster than (frequency)−1. For the low-frequency waves heavy ions are less effectively accelerated than lighter ions. However, very heavy ions can be preferentially accelerated, the abundances of the very heavy ions being enhanced by a factor Ai over the thermal abundances. Acceleration of ions in the envelope of the Crab nebula is considered as an example.

Improved cryogenic sapphire oscillator with exceptionally high frequency stability

2000 ◽  
Vol 36 (5) ◽  
pp. 480 ◽  
Author(s):  
S. Chang ◽  
A.G. Mann ◽  
A.N. Luiten
Keyword(s):  
High Frequency ◽  
Frequency Stability

Analysis and Optimization of Conformal Patch Excited Wideband DRA of Several Shapes

Frequenz ◽  
2018 ◽  
Vol 72 (5-6) ◽  
pp. 197-208 ◽  
Author(s):  
Pramod Kumar ◽  
Santanu Dwari ◽  
Shailendra Singh ◽  
Ashok Kumar ◽  
N. K. Agrawal ◽  
...  
Keyword(s):  
Comparative Analysis ◽  
Frequency Spectrum ◽  
High Frequency ◽  
Unit Volume ◽  
Experimental Results ◽  
Impedance Bandwidth ◽  
High Frequency Structure Simulator ◽  
Triangular Shape ◽  
Operating Band ◽  
Peak Gain

AbstractIn this paper various shapes of DR antennas excited by common feed have been proposed and successfully implemented for wideband applications. Proposed structures are Hemispherical, Arrow-shaped and Triangular DRA, while common excited feed is inverted trapezoidal conformal patch. These shapes of DR offer significant optimization in several parameters such as impedance bandwidth, peak gain and bandwidth per unit volume of the antenna. By using inverted trapezoidal patch feed mechanism an impedance bandwidth (VSWR<2) of about 63 % for hemispherical shape, 66 % for arrow shape, and 72 % for triangular shape DRA has been achieved with maximum bandwidth per unit volume. Proposed wideband DRAs i. e. triangular, hemispherical, and arrow shapes of DR antennas cover almost complete C-band (4 GHz–8 GHz) frequency spectrum of microwave. The average peak gain within the operating band for hemispherical, arrow, and triangular shape DRA are about 5, 5.4, and 5.5 dB respectively. A comparative analysis of proposed structures for various antenna parameters has been analyzed by HFSS (High-Frequency Structure Simulator) and validated by experimental results.

2-µm Doppler lidar transmitter with high frequency stability and low chirp

2000 ◽  
Vol 25 (17) ◽  
pp. 1228 ◽  
Author(s):  
V. Wulfmeyer ◽  
M. Randall ◽  
A. Brewer ◽  
R. M. Hardesty
Keyword(s):  
High Frequency ◽  
Frequency Stability ◽  
Doppler Lidar

LRI Instrument status talk

2020 ◽  
Author(s):  
Samuel Francis
Keyword(s):  
High Frequency ◽  
Laser Frequency ◽  
Frequency Stability ◽  
Current Status ◽  
Range Measurement ◽  
Best Estimate

&lt;p&gt;In this talk, the current status of the LRI instrument will be presented. Topics will include laser frequency stability since launch, current best estimate of the noises in the LRI range spectra, and a look at some high-frequency signals visible in the LRI range measurement.&lt;/p&gt;

The high-frequency spectrum of tungsten

1916 ◽  
Vol 182 (3) ◽  
pp. 403 ◽  
Author(s):  
Albert W. Hull ◽  
Marion Rice
Keyword(s):  
Frequency Spectrum ◽  
High Frequency ◽  
High Frequency Spectrum

High-frequency-stability diode-pumped Nd:YAG lasers with the FM sidebands method and Doppler-free iodine lines at 532 nm

1999 ◽  
Vol 38 (33) ◽  
pp. 6962 ◽  
Author(s):  
Gianluca Galzerano ◽  
Cesare Svelto ◽  
Elio Bava ◽  
Fabrizio Bertinetto
Keyword(s):  
High Frequency ◽  
Frequency Stability ◽  
Nd:Yag Lasers ◽  
Free Iodine ◽  
Diode Pumped ◽  
532 Nm

scholarly journals On High Frequency Polar Motion and Length of Day Variations

2000 ◽  
Vol 178 ◽  
pp. 545-554
Author(s):  
K. Arfa-Kaboodvand ◽  
E. Groten
Keyword(s):  
Frequency Spectrum ◽  
Earth Rotation ◽  
High Frequency ◽  
Polar Motion ◽  
Length Of Day ◽  
Physical Processes ◽  
Earth Orientation ◽  
Tidal Forces ◽  
Diurnal Range ◽  
Insight Into

AbstractThe 0.042-day Earth rotation data (diurnal and semidiurnal) computed by the International GPS Service were used to analyze the daily/sub-daily variations of polar motion (PM) and length of day (LOD). Systematic and advanced spectral analytical investigations of the degree of periodic variability have been carried out. They show that the prominent periodical components can be found at the tidal frequencies of zonal, tesseral and sectorial waves. These investigations should give better insight into the physical processes, which influence Earth orientation (i.e. due to the atmospheric and oceanic motions, tidal forces etc.). It should be the basis for the detailed modeling of excitation functions in the sub-diurnal range of the high-frequency spectrum.

High-Frequency Stability of Detonations and Turning Points at Infinity

2015 ◽  
Vol 47 (3) ◽  
pp. 1800-1878 ◽  
Author(s):  
Olivier Lafitte ◽  
Mark Williams ◽  
Kevin Zumbrun
Keyword(s):  
High Frequency ◽  
Turning Points ◽  
Frequency Stability
Sign in / Sign up

Export Citation Format

Share Document