Related papers: Rubidium transitions as wavelength reference for a…
This paper addresses alternative procedures to the ESO supplied pipeline procedures for the reduction of UVES spectra of two quasar spectra to determine the value of the fundamental constant mu = Mp/Me at early times in the universe. The…
Resolving sources beyond the diffraction limit is important in imaging, communications, and metrology. Current image-based methods of super-resolution require phase information (either of the source points or an added filter) and perfect…
We propose a tunable laser-based satellite-mounted spectrophotometric and absolute flux calibration system, to be utilized by ground- and space-based telescopes. As spectrophotometric calibration may play a significant role in the accuracy…
One of the main methods used for finding extrasolar planets is the radial velocity technique, in which the Doppler shift of a star due to an orbiting planet is measured. These measurements are typically performed using cross-dispersed…
Ro-vibrational spectra of different electronic states of molecules are often used as absolute wavelength or frequency standards. These standards are also used to mitigate any slow drift of laser frequency during an experiment. In precision…
A stable reference light source based on an LED (Light Emission Diode) is presented for stabilizing the conversion gain of the opto-electronic system of a gamma- and fast-neutron radiographic and tomographic imaging device. A constant…
We consider the application of relative self-calibration using overlap regions to spectroscopic galaxy surveys that use slit-less spectroscopy. This method is based on that developed for the SDSS by Padmanabhan at al. (2008) in that we…
We have developed a technique to measure the absolute frequencies of optical transitions by using an evacuated Rb-stabilized ring-cavity resonator as a transfer cavity. We study possible wavelength-dependent errors due to dispersion at the…
Rubidium two-photon frequency standards are emerging as powerful contenders for compact, durable devices with exceptional stability. The field has focused on single-color excitation to date. Here we demonstrate the key advantages of a…
We demonstrate stabilisation of an ultraviolet diode laser via Doppler free spectroscopy of Ytterbium ions in a discharge. Our technique employs polarization spectroscopy, which produces a natural dispersive lineshape whose zero-crossing is…
Here we report on measurements of the absolute absorption spectra of dense rubidium vapour on the D1 line in the weak-probe regime for temperatures up to 170 C and number densities up to 3 \times 10^14 cm^-3. In such vapours, modifications…
We present and characterize a laser system for the spectroscopy on highly-charged ^209Bi^82+ ions at a wavelength of 243.87 nm. For absolute frequency stabilization, the laser system is locked to a near-infra-red laser stabilized to a…
Growing interest in 21 cm tomography has led to the design and construction of broadband radio interferometers with low noise, moderate angular resolution, high spectral resolution, and wide fields of view. With characteristics somewhat…
The accurate determination and control of the wavelength of light is fundamental to many fields of science. Speckle patterns resulting from the interference of multiple reflections in disordered media are well-known to scramble the…
The interaction of hot atoms with laser fields experiences a Doppler shift which can severely affect the precise spatial measurement of an atom. We suggest an experimentally realizable scheme to address this issue in three-dimension…
Precision atomic spectroscopy is presently the work horse in quantum information technology, metrology, trace analysis and even for fundamental tests in physics. Stable lasers are inherent part of precision spectroscopy which in turn…
Flux calibration of spectra in reverberation mapping (RM) is most often performed by assuming the flux constancy of some specified narrow emission lines, which stem from an extended region that is sometimes partially spatially resolved, in…
Echelle spectrographs currently provide some of the most precise and detailed spectra in astronomy, the interpretation of which sometimes depends on the wavelength calibration accuracy. In some applications, such as constraining…
We present a new technique for calibrating the primary beam of a wide-field, drift-scanning antenna element. Drift-scan observing is not compatible with standard beam calibration routines, and the situation is further complicated by…
Many applications seek to measure a sample's absorption coefficient spectrum to retrieve the chemical makeup. Many real world samples are optically turbid, causing scattering confounds which many commercial spectrometers cannot address.…