Integrated acousto-optic collinear TE–TM mode convertors for 0.8 μm optical wavelength range

1991 ◽  
Vol 27 (13) ◽  
pp. 1211 ◽  
Author(s):  
I. Hinkov ◽  
V. Hinkov
Keyword(s):  
Wavelength Range ◽  
Optical Wavelength ◽  
Tm Mode

Dissecting quasars with the J-PAS narrow-band photometric survey

2019 ◽  
Vol 15 (S356) ◽  
pp. 12-16
Author(s):  
Silvia Bonoli ◽  
Giorgio Calderone ◽  
Raul Abramo ◽  
Jailson Alcaniz ◽  
Narciso Benitez ◽  
...  
Keyword(s):  
Emission Line ◽  
Wavelength Range ◽  
Software Package ◽  
Narrow Band ◽  
Active Galaxies ◽  
Emission Lines ◽  
Low Resolution ◽  
Strong Emission ◽  
Optical Wavelength ◽  
Quasar Spectra

AbstractThe J-PAS survey will soon start observing thousands of square degrees of the Northern Sky with its unique set of 56 narrow band filters covering the entire optical wavelength range, providing, effectively, a low resolution spectra for every object detected. Active galaxies and quasars, thanks to their strong emission lines, can be easily identified and characterized with J-PAS data. A variety of studies can be performed, from IFU-like analysis of local AGN, to clustering of high-z quasars. We also expect to be able to extract intrinsic physical quasar properties from the J-PAS pseudo-spectra, including continuum slope and emission line luminosities. Here we show the first attempts of using the QSFit software package to derive the properties for 22 quasars at 0.8 < z < 2 observed by the miniJPAS survey, the first deg2 of J-PAS data obtained with an interim camera. Results are compared with the ones obtained by applying the same software to SDSS quasar spectra.

Preliminary Investigation of Laser Induced Photoconductivity in 4H-SiC PiN Diodes and HPSI Substrate

2010 ◽  
Vol 645-648 ◽  
pp. 917-920
Author(s):  
Bertrand Vergne ◽  
Sigo Scharnholz ◽  
Jens Peter Konrath ◽  
Vincent Couderc ◽  
Philippe Lévêque ◽  
...  
Keyword(s):  
Penetration Depth ◽  
Wavelength Range ◽  
High Purity ◽  
Preliminary Investigation ◽  
Electrical Field ◽  
Pin Diodes ◽  
Optical Wavelength

We present photoconductivity experiments on a 4H-SiC diode and on 4H-SiC high purity semi-insulating (HPSI) substrate. These devices have been tested over a wide optical wavelength range: 355 nm to 820 nm. The penetration depth of optical wavelength has been estimated from spectrophotometer measurements. Photoconductivity regime has been studied at low electrical field for both devices and photoconductivity efficiency has been compared to Si switches.

Spectrum of comet C/2009 P1 (Garradd) in the optical wavelength range

2014 ◽  
Vol 30 (6) ◽  
pp. 276-287 ◽  
Author(s):  
O. S. Shubina ◽  
P. P. Korsun ◽  
V. L. Afanasiev
Keyword(s):  
Wavelength Range ◽  
Optical Wavelength

scholarly journals MODEL OF TRANSMISSION OF MULTILAYER COATINGS BASED ON THE Cu-ZrO2 SYSTEM IN THE OPTICAL WAVELENGTH RANGE

Doklady BGUIR ◽  
2019 ◽  
pp. 87-94
Author(s):  
A. T. Volochko ◽  
V. A. Zelenin ◽  
E. O. Narushko ◽  
A. V. Skilandz ◽  
G. V. Markov
Keyword(s):  
Wavelength Range ◽  
Multilayer Coating ◽  
Transmission Model ◽  
Multilayer Coatings ◽  
Glass Substrates ◽  
Optical Wavelength ◽  
Light Interference ◽  
Number Of Layers ◽  
20 Nm ◽  
Zro2 System

The transmission model for optical diapason was developed for multilayer coatings consisting of alternating layers of copper and zirconium dioxide deposited on K8 glass substrates. The model is based on the laws of light interference. It was shown that the transmission in the optical range of a 60 nm thick Cu layer with a surface resistance ρ = 1 Ohm/sq is 4–5 %, and the transmission of the ZrO2/Cu/ZrO2/Cu/К8 coating obtained by dividing a 60 nm thick copper layer into two sublayers at 30 nm with the application of antireflection layers of ZrO2 on them, at ρ = 1.2 Ohm/sq it reaches 25 %. The thicknesses and the number of layers of the Cu-ZrO2 system were calculated, which ensure a transmission in the wavelength range of 400–700 nm of at least 45 %. The permissible thickness of Cu layers (≥ 20 nm) was determined, below which, due to their insular structure and partial oxidation with the formation of Cu2O, the electrical conductivity of the multilayer coating sharply decreases (ρ ≥ 100 Ohm/sq).  

Model Calculations and Spectroscopic Constrains for SN1987A

1988 ◽  
Vol 108 ◽  
pp. 288-294 ◽  
Author(s):  
P. Höflich
Keyword(s):  
Wavelength Range ◽  
Radiation Transport ◽  
Stellar Structure ◽  
Rate Equations ◽  
Pure Hydrogen ◽  
Model Calculations ◽  
Optical Wavelength ◽  
Initial Event ◽  
Hydrogen Mass ◽  
Process Elements

SummaryWe present synthetic spectra for atmospheres in order to interpret the observed spectra of the supernova 1987A during the first few months after the initial event. Spherical symmetry and density profiles are assumed which are given by the homologous expansion of the stellar structure of a B3 supergiant. For hydrogen, up to eight levels and, for helium, 16 levels are allowed to deviate from LTE. The radiation transport is calculated consistently with the rate equations both for the continua and for the lines. Radiative equilibrium is assumed. The observed spectra and colours in the optical wavelength range can be well reproduced by pure hydrogen models during the first few weeks. The behaviour of the UV flux is due to changes in the effective temperature and the photospheric radius. For later stages, the influence of elements other than hydrogen and helium must be taken into account in order to compare the calculated and observed spectra in the optical wavelength range. Reasonable agreement between calculations and observations can be obtained with the assumption of half solar abundances for all elements but for the s-process elements Sc, Ti and Ba which are overabundant. To explain the small changes in the spectra after about 3 weeks up to 4 months, we need a total hydrogen mass of about 8 to 10 M⊙.

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