... Title : EXTENSION OF ABSOLUTE FREQUENCY MEASUREMENTS TO 148 THZ: FREQUENCIES OF THE 20- AND 35- MICRONS XE LASER, IN ...

... CURRENT UNDERSTANDING OF THE ABSOLUTE MEASUREMENTS OF THE AMOUNT, FREQUENCY SPECTRA, AND WAVE FORMS OF THE ...

Absolute frequency measurement and spectroscopy of gas laser transitions in far IR, analyzing Zeeman

... Accession Number : ADA083457. Title : Absolute Frequency Measurements of N2O Laser Transitions,. Corporate Author ...

A highly sensitive technique for making absolute measurements of power at all radio frequencies is described. This technique surmounts the primary shortcomings of the other existing techniques in that it permits absolute measurement of power at all radio ...

It is proposed to use radiation from a femtosecond laser for absolute length measurements. The possibility of creation of a unified frequency and length standard is shown. (laser applications and other topics in quantum electronics)

... Accession Number : ADA293930. Title : Optical Frequency Standards: Hertz-Level Working Standards and their Absolute Frequency Measurement. ...

A method for precise measurements of absolute electron density in the plasma using plasma frequency is developed. A microwave perturbation of a frequency is introduced to plasma from a network analyzer and transmits in the plasma. The transmitting wave at a distance from a radiating antenna is monitored using a ...

Absolute frequency measurement of the iodine-stabilized Ar+ laser at 514.6 nm using a femtosecond laser frequency comb generator. The measured frequency at an iodine pressure of 0.12 Pa is 67.3(0.75) k frequency comb transfer oscillator. Secondary laser ...

... The absolute Raman cross-sections of diamond and graphite have been measured, II and it is ... RAMAN SHIFT (cm-1) I ... Frequency Shift (cm-') ...

... ALL THE LASERS EXHIBITED A STABILITY OF 1 PART IN 10 TO ... AN ABSOLUTE ACCURACY OF APPROXIMATELY 1 PART IN 10 TO THE 9TH ...

... clearance by measuring the time interval required for a radio frequency signal ... time required for the test item to become operational after activation. ...

... helium-neon laser as a light source, absolute displacement measurements can be obtained over the frequency range of approximately 2 to 30 kHz. ...

When supplemented by absolute reflection height measurements, low frequency wind measurements in the

Here we report on absolute frequency measurements of a commercial high power CW diode-pumped solid-state laser (Coherent Verdi-V5). This kind of lasers usually presents large frequency jitter (up to 50 MHz) both in the short term (1 ms time scale) and in the long term (>10 s time scale). A precise ...

Retention of frequency discriminations among words were determined for three intervals (0, 1, and 7 days) and for presented frequencies of from 1 through 6. Comparative judgments and absolute judgments were used to measure frequency discrimination. All Ss...

... to measure the absolute flux densities of the emission of four discrete sources in frequency bands between 12 and 40 mHz: Cassiopeia A, Cygnus A ...

A transverse-flow mixing HF/DF laser transition was frequency stabilized to better than 500 kHz relative to the second harmonic of a CO laser using a heterodyne technique. An absolute frequency of 110 725 697.4 +- 7 MHz was measured for the 1-OP (6) line of the HF laser, which represents a factor of 100 ...

A split-pulse spectrometer based on pairs of time-delayed femtosecond pulses can give access to accurate frequency measurements in the extreme ultraviolet (XUV) spectral domain. We demonstrate this approach by measuring the absolute frequency of a single-XUV-photon transition to a bound state ...

Avoidance conditioning and the method of limits were used to measure absolute auditory thresholds, masked thresholds, and critical ratios in 4 parakeets. The same procedure was then used to study frequency difference limens in 6 additional animals. The power spectrum and "constancy of intonation" of the parakeet call were also ...

Contents: Lasers for an optical frequency standard using trapped Hg+ ions; Direct comparison of two cold-atom-based optical frequency standards by using a femtosecond-laser comb; Absolute frequency measurements of the Hg+ and Ca optical clock transitions ...

In general, the effectiveness of in-line devices for protection of electric initiators from radio frequency electromagnetic hazards depends upon absolute parameters of the loaded devices plus parameters of the external electrical circuits. The absolute pa...

The absolute frequency of a CO/sub 2/:OsO/sub 4/ laser is measured. The possibility of measuring with the standard accuracy the frequencies of lasers operating at transitions of shorter wavelengths (>28 THz) and setting up an experiment for verification of the hypothesis of variation of the ...

... of tadar data fro2 chaff clouds where absolutely everything in time dependent - radar cross section, polarisation ratios, frequency response, Doppler ...

... 1.5 of a single frequency s+nu,*. ... given by Raman and Nath' 09 except that the equations of Raman and Nath ... beam does not cross the optical xiath. ...

The extension of absolute frequency measuring techniques to the infrared (3.4 micrometers) has been made possible with the development of the tungsten-nickel point contact diode. Saturated absorption stabilized lasers now provide sources sufficiently stab...

Fifty specified lines of {sup 127}I{sub 2} were studied by Doppler-free frequency modulation spectroscopy. For each line the classification of the molecular transition was determined, hyperfine components were identified, and one well-resolved component was selected for precise determination of its absolute frequency. In 3 cases, a ...

It is important to understand how the quality of people's decision making may be affected by the format used to present treatment benefits. Two experiments compared the accuracy of presenting the benefits of cancer screening tests or vaccines using either absolute or relative risk formats that included baseline risk information. Moreover, the absolute ...

The mode number of the comb line involved in the optical frequency measurement was determined using two mode-locked, erbium-doped fiber laser combs operated at different repetition rates independently of the frequency fluctuation of the laser under measurement (LUM). A simple measurement ...

The possibility of deep parametric decay instability suppression by launching a complementary (small power) pump wave possessing a slightly shifted frequency is demonstrated experimentally. This suppression is achieved at an additional pump wave frequency shift equal to the frequency separation of ion acoustic eigenmodes excited in ...

We report on the absolute frequency measurement of an extended-cavity diode laser stabilized against a Doppler-free vibration-rotation transition of the H2 18O isotopologue near 1.384 ?m. Absolute determination is performed by comparing the water-stabilized laser frequency with respect to a ...

We report the measurement of absolute excitation frequencies of Rb87 to nS and nD Rydberg states. The Rydberg transition frequencies are obtained by observing electromagnetically induced transparency on a rubidium vapor cell. The accuracy of the measurement of each state is ?1 MHz, which is ...

Frequency doubled Nd:YAG lasers are often the option with stabilization to the saturated absorption in molecular iodine featuring good signal-to-noise ratio at the 532 nm. Purity of iodine in the absorption cell is one of the most important factor how to achieve results in optical frequencies corresponding to theoretical values. We present results of ...

By using external-gain, hydrogen-maser oscillations were obtained at cavity Q values and beam intensities far below those required for a conventional hydrogen maser. Frequency-pulling measurements and absolute frequency determinations of the hydrogen mase...

A system for making an absolute measurement of the wavelength and frequency of a stabilized carbon-dioxide laser is under construction. The wavelength has been measured by an up-conversion technique using Proustite with reference to an iodine stabilized l...

In this paper we describe the calibration of a photometer designed to measure the cosmic microwave background radiation in the frequency range from 3 to 10 cm exp -1 . The general problem of absolute calibration for such measurements is discussed. The des...

... Accession Number : AD0667289. Title : ABSOLUTE CALIBRATION OF REFERENCE HYDROPHONES IN THE AUDIO FREQUENCY RANGE,. ...

A 3-microm continuous-wave difference-frequency source is directly referenced to a mid-infrared optical frequency comb synthesizer by measuring their beat-note signal by a fast HgCdTe detector. Absolute frequency metrology of molecular vibration spectra is demonstrated by locking the 3-microm ...

Absolute distance measurement based on optical feedback using a single-frequency Yb:Er glass laser is demonstrated via the combination of heterodyne detection and frequency sweep. The technique allows for the enhancement of the sensitivity of the laser response to self-mixing thanks to resonant excitation close to ...

Absolute distance measurement based on optical feedback using a single-frequency Yb:Er glass laser is demonstrated via the combination of heterodyne detection and frequency sweep. The technique allows for the enhancement of the sensitivity of the laser response to self-mixing thanks to resonant excitation close to ...

A small spherical probe is used in conjunction with a network analyzer to determine the impedance of the probe-plasma system over a wide frequency range. Impedance curves are in good agreement with accepted circuit models with plasma-sheath and electron plasma frequency resonances easily identifiable. Clear transitions between capacitive and inductive ...

... Title : Characteristic Functional of a Probability Measure Absolutely Continuous with Respect to a Gaussian Radon Measure. ...

We report high-precision absolute distance and vibration measurements performed with frequency scanned interferometry using a pair of single-mode optical fibers. Absolute distance was determined by counting the interference fringes produced while scanning the laser frequency. A high-finesse ...

We report high-precision absolute distance and vibration measurements performed with frequency scanned interferometry using a pair of single-mode optical fibers. Absolute distance was determined by counting the interference fringes produced while scanning the laser frequency. A high-finesse ...

We report the absolute frequency measurement of the 81.5 ?m rotational transition and of the 263.4 ?m inversion transition in the ?2 vibrational state of 14NH3. A very low-phase noise frequency multiplication chain has been used in the experiments allowing a phase-coherent synthesis up to the ...

Absolute frequency measurement has been extended to the visible spectrum with the measurement of the strong 1.15 micrometers laser line in (20)Ne at 260 THz and lines in iodine at twice this frequency. The 260 THz frequency was synthesized in nonlinear crystals of ...

We report the first measurement of the saturation of stimulated Brillouin scattering (SBS) by an ion-trapping induced frequency shift, which was achieved by directly measuring the amplitude and absolute frequency of SBS-driven ion-acoustic waves (IAW). A frequency shift of ...

... Title : Absolute Gravity Measurements with Reversible Pendulums at Potsdam, 1968-1969 (Absolute Schwaremessungen mit Reversionpendein in ...

The frequencies of the hyperfine components of the 1(10) to 1(11) rotational transition of H2CO have been measured with a molecular-beam maser to an absolute precision of about 1 part in 10 to the 8th power. (Author)

A nonincremental interferometer for the absolute measurement of distances is presented. The measuring technique is based on both dispersive white-light (DWL) interferometry and frequency-modulated continuous-wave (FMCW) interferometry. The proposed configuration integrates both techniques in the same interferometer ...

Absolute distance measurement using optical feedback with heterodyne detection has been demonstrated by sweeping the optical frequency of a single longitudinal mode (SLM) Yb:Er glass laser. This technique allows enhancing the sensitivity of the laser response to self-mixing thanks to resonant excitation close to the relaxation ...

A three-step laser excitation scheme is used to make absolute frequency measurements of highly excited nF7/2 Rydberg states in 85Rb for principal quantum numbers n=33-100. This work demonstrates the first absolute frequency measurements of rubidium Rydberg levels using a ...

The hypothesis that equivalent sounds (dBA) at different frequencies produce the same temporary threshold shifts (TTS) is analyzed in order to justify the utilization of A weighting to measure noise fatigue effects. After recording the audiograms of subjects using frequencies from 125 to 8000 Hz and measuring the ...

We report on an accuracy limit test result of the optical frequency comb technique by comparing the frequencies of two optical frequency combs that operate in two different modes. These two modes are distinguished by the reference frequency for the comb frequency stabilization; an optical ...

The MSTAR sensor (Modulation Sideband Technology for Absolute Ranging) is a new system for measuring

... Accession Number : AD0616613. Title : AN ABSOLUTE MEASUREMENT OF THERMAL NEUTRON ALBEDO FOR SEVERAL MATERIALS. ...

... for Absolute Measurements at the ... of a Lyman-alpha photometer on ... MAGNETOSPHERE, ULTRAVIOLET RADIATION), SCIENTIFIC SATELLITES ...

The phase locking of diode lasers to the frequency component (mode) of the output radiation of a highly stable femtosecond Ti:sapphire laser, resulting in the amplification of the mode power by several orders of magnitude, is reported. The possibilities of using femtosecond lasers for creation of a new generation of miniature optical clocks and for synthesis and ...

A simple technique to generate an optical frequency comb, based on a conventional dual-drive Mach-Zehnder intensity modulator, has been used as optical source for a high accuracy distance measurement in an interferometric set-up. The modulator has been driven by a direct-digital synthesizer that is able to deliver a pure ramp in ...

In this work, an absolute distance measurement method based on the self-mixing interference is presented. The principles of the method used three-mirror cavity equivalent model are studied in this paper, and the mathematical model is given. Wavelength modulation of the laser beam is obtained by saw-tooth modulating the infection current of the laser diode. ...

Coherent anti-Stokes Raman spectroscopy (CARS) is combined with high-resolution interferometry to measure the absolute Raman shift of the Q(2) vibrational line in D(2). The preliminary value found is 2987.237(1) +/- 0.001 cm(-1). Such precision is essential for the testing of ab initio energy-level calculations for the hydrogen isotopes. PMID:19680361

A new low-cost superheterodyne configuration, without acousto-optic modulator, is applied to the two-wavelength interferometry for absolute distance measurement. The principle relies on a synchronized frequency sweep of two optical signals, but with different frequency excursions. The frequency ...

We report greater than two orders of magnitude improvements in the absolute frequency and isotope shift measurements of the In+ 5s2 1S0 (F = 9/2) 5s5p 3P1 (F = 11/2) transition near 230.6 nm. The laser-induced fluorescence from a single In+ in a radio-frequency trap is detected. The fourth-harmonic of a ...

A highly sensitive technique for making absolute measurements of power at all radio frequencies is described. This technique surmounts the primary shortcomings of the other existing techniques in that it permits absolute measurement of power at all radio frequencies, ...

We attained an accuracy of 10/sup 13/ in the absolute measurements of the frequencies of long-wave lasers, including CO/sub 2/ lasers. The measurement accuracy is 1 x 10/sup 10/ in the shorter wavelength region of the IR (to 3.39 ..mu..m). The frequency of the CO/sub 2/:OsO/sub 4/ laser is ...

A frequency-spectrum analyzer with phase-lock for analyzing the frequency and amplitude of an input signal is comprised of a voltage controlled oscillator (VCO) which is driven by a ramp generator, and a phase error detector circuit. The phase error detector circuit measures the difference in phase between the VCO and the input signal, ...

By defining the operating environment of turbomachinery blading in terms of absolute and relative velocity fields, airfoil dynamic mode shapes, and reduced frequency ranges, the applicability of various flow facilities in establishing critical time varyin...

Absolute times of arrival of NP 0532 pulses have been measured over a 2-year period. The data are shown to be consistent with a cubic polynomial which describes the secular slowdown, a sudden increase and subsequent exponential decay of the frequency (the...

A reactivity measurement method (the NTFODRS) was experimentally verified on the University of New Mexico (UNM) AGN-201M thermal reactor to obtain the absolute steady-state reactivity and demonstrate the feasibility of acquiring the transient reactivity. ...

-0 : , with uncertainties mainly due to the presently-limited accuracy of R(56) 32-0 : . II. I TRANSISTIONS NEAR 532 nm

For the past 50 years, atomic standards based on the frequency of the cesium ground-state hyperfine transition have been the most accurate time pieces in the world. We now report a comparison between the cesium fountain standard NIST-F1, which has been evaluated with an inaccuracy of about 4x10{sup -16}, and an optical frequency standard based on an ...

We obtain a heterodyne beat signal between an iodine-stabilized He-Ne laser at 633 nm and a low power comb mode of an optical frequency synthesizer with an enhanced signal-to-noise ratio (SNR) up to{approx}35 dB. This is accomplished by the adoption of a fiber coupler and the reduction of the shot noise induced by adjacent comb modes. SNR is improved more than 15 dB compared ...

We have established a frequency measurement system for frequency-stabilized lasers operating in telecommunication wavelength bands, by using a femtosecond optical comb without the need for carrier envelope offset frequency control. This system has been used to measure the ...

We have established a frequency measurement system for frequency-stabilized lasers operating in telecommunication wavelength bands, by using a femtosecond optical comb without the need for carrier envelope offset frequency control. This system has been used to measure the ...

... Title : REMOTE AEROSOL SENSING WITH AN ABSOLUTE CALIBRATED DOUBLE FREQUENCY LIDAR, IN: AGARD-CP-183, PAPER 4. ...

... Accession Number : AD0178854. Title : ABSOLUTE CAPACITANCE MICROCREEP AND DIMENSIONAL STABILITY MEASURING SYSTEM. ...

Whistler mode wave emissions in the magnetosheath, known as lion roars, are thought to be generated by an electron cyclotron instability. Reported satellite data are used to model a magnetosheath medium where lion roars emissions occurred, and the character, absolute or convective, of the associated electron cyclotron instability is studied. A linear hot plasma dispersion ...

This paper describes a threshold track-and-hold device for determining the event time of the absolute maximum in a realiaztion of a stochastic process of finite duration. The range of input signal levels is + or - 3 V, and the upper frequency limit is greater than or equal to500 kHz. The absolute measurement error ...

... Absolute Measurement of Sound Pressure in Liquids. ... of Plane, Finite Amplitude Waves in a ... Optical Method for Ultrasonic Velocity Measurements at ...

The frequency of the 5s {sup 2}S{sub 1/2}-4d {sup 2}D{sub 5/2} electric quadrupole transition at 674 nm in a single, trapped, laser-cooled {sup 88}Sr{sup +} ion has been measured with respect to the Systeme International (SI) second using a femtosecond laser optical frequency comb. The measured ...

A collinear fast ion beam laser apparatus was constructed and tested. It will be used on-line to the SLOW RI radioactive beam facility in RIKEN (Japan) and as in the present experiment for precision absolute frequency measurements of astrophysically important reference lines. In the current work we conducted ...

The Phase 1 project focused on the development of a multiwave interferometer to measure absolute distance. Its applications are in gauging and for measuring absolute position of machine tools, and coordinate measuring machines. This interferometer overcom...

A simpler, one-step method to stabilize the Ti:sapphire laser is described. The frequency modulation (FM) spectroscopy is applied to a Lamb-dip cell to obtain a dispersive error signal, which then provides a negative feedback signal to correct the frequency error of the laser. Counter propagating pump and probe beams having the same ...

The frequency dependence of the nonlinear optical susceptibilities of fused quartz and four other glasses were determined along with the relative contributions of electronic and nuclear mechanisms to their nonlinear optical indices. This is the first such determination in solids. The method has been to analyze the absolute measurement ...

way of such a test is to compare iodine cells at different institutes. Work along this line is also of Independent Optical Frequency Measurements Using a Portable Iodine-Stabilized Nd:YAG Laser Feng-Lei Hong, Jun), Boulder, CO, using a portable iodine-stabilized Nd:YAG laser. The agreement between the two absolute

The hyperfine structure splittings of the P(10)14-1, R(15)14-1, and R(99)15-1 transitions at 585 nm, P(62)17-1 at 576 nm, and P(80)21-1 at 565 nm in 127I2 are measured by heterodyne spectroscopy using two dye lasers. In addition, the absolute frequencies of the hyperfine components P(10)14-1 a15 and P(80)21-1 a10 are determined using a ...

In frequency modulated continuous wave reflectometry, used for density profile measurement in fusion plasmas, it is usual to measure the beat frequency between the launched wave and the reflected wave, and from this to calculate the position of the reflecting layer in the plasma. The absolute ...

The frequency comb created by a femtosecond mode-locked laser and a microstructured fiber is used to phase coherently measure the frequencies of both the Hg+ and Ca optical standards with respect to the SI second. We find the transition frequencies to be f(Hg) = 1 064 721 609 899 143(10) Hz and f(Ca) = 455 986 240 ...

The task of anti-aliasing in absolute profile measurement by multi-sensor scanning techniques is considered. Simulation results are presented which demonstrate that aliasing can be highly reduced by a suitable choice of the scanning steps. The simulation results were confirmed by results obtained for interferometric measurements ...

The authors review recent measurements of the high-frequency dynamic magnetic susceptibility in the high-T{sub c} superconducting systems La{sub 2{minus}x}Sr{sub x}CuO{sub 4} and YBa{sub 2}Cu{sub 3}O{sub 6+x}. Experiments were performed using the chopper spectrometers HET and MARI at the ISIS spallation source. The authors have placed their ...

Interferometric range measurements using a wavelength-tunable source form the basis of several measurement techniques, including optical frequency domain reflectometry (OFDR), swept-source optical coherence tomography (SS-OCT), and frequency-modulated continuous wave (FMCW) lidar. We present a phase-sensitive and ...

Frequency-domain tissue spectroscopy is a method to measure the absolute absorption coefficient of bulk tissues, assuming that a representative model can be found to recover the optical properties from measurements. While reliable methods exist to calculate absorption coefficients from source-detector ...

Single or double ion chamber technique measures absolute radiation intensities in the extreme vacuum

... ABSOLUTE POSITION MEASUREMENT FOR AUTOMATED GUIDED VEHICLES USING THE GREEDY DEBRUIJN SEQUENCE by John E. Ortiz ...

... Title : Absolute Concentration Measurements of Free Radicals in Flames by Absorption Spectroscopy. Descriptive Note : Final rept. ...

... Title : Absolute Absorption Cross Section Measurements of Ozone and the Temperature Dependence at Four Reference Wavelengths Leading to ...

... Accession Number : AD0625664. Title : ABSOLUTE SPECTRAL DISTRIBUTION MEASUREMENTS OF XENON HIGH-PRESSURE DISCHARGES. ...

... Accession Number : AD0190479. Title : ABSOLUTE LENGTH MEASUREMENT AT HIGH PRESSURE. Corporate Author : ...

... AD0822914. Title : ABSOLUTE DOSE MEASUREMENTS ON A MEGACURIE CO-60 SOURCE BY MEANS OF CALORIMETRY. ...

... Accession Number : AD0771216. Title : A Simple Method for Measuring Absolute Diffuse Reflectance with a Laboratory Spectrophotometer. ...

We characterize and compare the performance of various commercially available lasers in terms of their absolute frequency stability, lineshape, linewidth, and frequency noise. The frequency stability, linewidth and lineshape are evaluated using an 'optical ruler' - a carrier-envelope stabilized optical comb. The ...

A laser system composed of two lasers phase-locked onto an Optical Frequency Comb Synthesizer (OFCS), operating around 1083 nm, was developed. An absolute frequency precision of 6x10(-13) at 1s, limited by the OFCS, was measured with a residual rms phase-noise of 71 mrad and 87 mrad for the two phase-locks, ...

We report on precision laser spectroscopy of the 2S(1/2)(F = 0)-2D(3/2) (F = 2, m(F) = 0) clock transition in a single ion of 171Yb+. The absolute value of the transition frequency, determined using an optical frequency comb referenced to a hydrogen maser, is 688358979309310 +/- 9 Hz. This corresponds to a fractional ...

The frequency comb of a femtosecond laser can be used like a ruler for length metrology. This permits measuring absolute distances with direct traceability to the atomic Cesium clock of the time standard. Optical frequency combs have received much attention in recent years due to their enormous potential in optical ...

Absolute measurements of spectral lines of Ar+ ions using collinear and anticollinear geometries were performed. To provide a precise reference for the laser wavelength, iodine saturation spectroscopy was applied. The precision of this reference is effected by observing the beat node between the spectroscopy laser and the corresponding mode of a ...

... In measuring frequency response functions and In ... matrix corresponding to a particular frequency, , ... corresponding to different frequencies are also ...