57 research outputs found
Cavity Enhanced Optical Vernier Spectroscopy, Broad Band, High Resolution, High Sensitivity
A femtosecond frequency comb provides a vast number of equidistantly spaced
narrow band laser modes that can be simultaneously tuned and frequency
calibrated with 15 digits accuracy. Our Vernier spectrometer utilizes all of
theses modes in a massively parallel manner to rapidly record both absorption
and dispersion spectra with a sensitivity that is provided by a high finesse
broad band optical resonator and a resolution that is only limited by the
frequency comb line width while keeping the required setup simple.Comment: 11 pages, 3 figures, submitted to PR
Refractive Index of Humid Air in the Infrared: Model Fits
The theory of summation of electromagnetic line transitions is used to
tabulate the Taylor expansion of the refractive index of humid air over the
basic independent parameters (temperature, pressure, humidity, wavelength) in
five separate infrared regions from the H to the Q band at a fixed percentage
of Carbon Dioxide. These are least-squares fits to raw, highly resolved spectra
for a set of temperatures from 10 to 25 C, a set of pressures from 500 to 1023
hPa, and a set of relative humidities from 5 to 60%. These choices reflect the
prospective application to characterize ambient air at mountain altitudes of
astronomical telescopes.Comment: Corrected exponents of c0ref, c1ref and c1p in Table
Photoexcitation and ionization in molecular fluorine: Stieltjes–Tchebycheff calculations in the static‐exchange approximation
Wei Hua's Four Parameter Potential Comments and Computation of Moleculer Constants \alpha_e and \omega_e x_e
The value of adjustable parameter and the four-parameter potential has been expressed in terms of molecular parameters and its significance
has been brought out. The potential so constructed, with derived from the
molecular parameters, has been applied to ten electronic states in addition to
the states studied by Wei Hua. Average mean deviation has been found to be 3.47
as compared to 6.93, 6.95 and 9.72 obtained from Levine2, Varshni and Morse
potentials, respectively. Also Dunham's method has been used to express
rotation-vibration interaction constant and anharmonocity
constant in terms of and other molecular constants.
These relations have been employed to determine these quantities for 37
electronic states. For , the average mean deviation is 7.2%
compared to 19.7% for Lippincott's potential which is known to be the best to
predict the values. Average mean deviation for turns out to
be 17.4% which is almost the same as found from Lippincott's potential
function.Comment: 19 RevTex Pages, 1 Ps figure, submitted to J. Phys.
Current assessment of the Red Rectangle band problem
In this paper we discuss our insights into several key problems in the
identification of the Red Rectangle Bands (RRBs). We have combined three
independent sets of observations in order to try to define the constraints
guiding the bands. We provide a summary of the general behavior of the bands
and review the evidence for a molecular origin of the bands. The extent,
composition, and possible absorption effects of the bands are discussed.
Comparison spectra of the strongest band obtained at three different spectral
resolutions suggests that an intrinsic line width of individual rotational
lines can be deduced. Spectroscopic models of several relatively simple
molecules were examined in order to investigate where the current data are
weak. Suggestions are made for future studies to enhance our understanding of
these enigmatic bands
Absolute differential cross sections for electron-impact excitation of CO near threshold: II. The Rydberg states of CO
Chemiluminescent Emission of CO Fourth Positive Bands in Nitrogen Atom/Oxygen Atom/Reactive Carbon Compound Systems. Relation to Chemi‐ionization
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