objectives in this study, the absorption coefficient of hemoglobin (hb) was used to distinguish between normal and abnormal breast tissue. materials and methods a near-infrared source (637 nm) was transmitted from major and minor vessels of a breast phantom containing 2×, 4× concentrations of oxy- and deoxy-hb. the absorption coefficients were determined from spectrometer (sm) and powermeter (p...

background: similar to the thermoluminescence (tl) spectra, the optical parameters variations can also be used in tl crystals for dosimetry purposes. these optical parameters can include absorption, transmission and reflection coefficients. materials and methods: single crystals of kbr and kcl which have been used in this research were grown from laboratory grade extra pure precursor powders. c...

We present low and intermediate resolution spectroscopy of the optical counterpart to the recently discovered pulsating X-ray source 1WGA J1958.2+3232. The presence of strong H i, He i and He ii emission lines together with the absence of absorption features rules out the possibility that the object is a massive star, as had recently been suggested. The observed X-ray and optical characteristic...

Near-field optical spectroscopy is used to investigate the effects of disorder in the optical processes in semiconductor quantum wires. We observe photoluminescence emissions from extended, delocalized excitons at low temperatures ~5 K! and low excitation densities. Combining high spectral and spatial resolution, we isolate homogeneous emission lines from excitons delocalized over distances up ...

In order to implement an integrated optical quantum circuit, designing waveguides based on the quantum box is of prime importance. To do this we have investigated optical waveguide both with and without optical pumping. The rate of absorption and emission using an array of AlGaAs/GaAs quantum box core/shell structure in the optical waveguide with various pumping intensities has computed. By con...

A procedure for the reconstruction of electron energy distribution functions (EEDF) of low-temperature neon plasmas from optical emission spectroscopy data is presented. A data descriptive model, including the physics of the plasma discharge and the spectroscopic measurement is developed. Particular refinements of the model regarding the apparatus function of the spectrometer and the optical de...

We present low and intermediate resolution spectroscopy of the optical counterpart to the recently discovered pulsating X-ray source 1WGA J1958.2+3232. The presence of strong H i, He i and He ii emission lines together with the absence of absorption features rules out the possibility that the object is a massive star, as had recently been suggested. The observed X-ray and optical characteristic...

We present ground-based near-infrared imaging and HST optical imaging and spectroscopy of the interaction between the ejecta of SN 1987A and its equatorial circumstellar ring. This interaction has made a transition, from emission originating in just a few “hot spots” at restricted locations in position angle around the ring, to a collision producing optical emission over a nearly continuous dis...

The breakthrough of laser cooling in semiconductor has stimulated strong interest in further scaling up towards practical optical refrigeration. The challenge is the stoichiometric defect in bulk crystal which introduces mid-gap states that manifest as broad-band long-wavelength emission. In this project, we have developed optical floating zone method to grown millimeter-scale CdS bulk crystals...

We present an analysis of time-resolved optical emissions observed from the gamma-ray burst GRB 081126 during the prompt phase. The analysis employed time resolved photometry using optical data obtained by the TAROT telescope, using BAT data from the Swift spacecraft and time resolved spectroscopy at high energies from the GBM instrument onboard the Fermi spacecraft. The optical emission of GRB...