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Optical System For Imaging And Low Resolution Integrated Spectroscopy
The Optical System for Imaging and low Resolution Integrated Spectroscopy (OSIRIS) is an optical spectrometer at the Gran Telescopio Canarias (GTC) in Spain. It was the first instrument in operation at the GTC. OSIRIS's key scientific project is OTELO. Sensitive in the wavelength range from 365 through 1000 nm, OSIRIS is a multiple purpose instrument for imaging and low-resolution long slit and multiple object spectroscopy (MOS). Imaging can be done using broad-band filters or narrow-band tunable filters with FWHM ranging from 0.2 to 0.9 nm at 365 nm, through 0.9 to 1.2 at 1000 nm. OSIRIS observing modes include also fast photometry and spectroscopy. OSIRIS's field of view is of 8.5×8.5 arcminutes and the maximum nominal spectral resolution is of 5000 for a slit width of 0.6 arcsec. MOS incorporates detector charge shuffling co-ordinated with telescope nodding for an excellent sky subtraction. The use of tunable filters is a completely new feature in 8 to 10 m class telescope ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Optical Spectrometer
An optical spectrometer (spectrophotometer, spectrograph or spectroscope) is an instrument used to measure properties of light over a specific portion of the electromagnetic spectrum, typically used in spectroscopic analysis to identify materials. The variable measured is most often the light's Intensity (physics), intensity but could also, for instance, be the Polarization (waves), polarization state. The independent variable is usually the wavelength of the light or a unit directly proportional to the photon energy, such as Wavenumber, reciprocal centimeters or electron volts, which has a reciprocal relationship to wavelength. A spectrometer is used in spectroscopy for producing spectral lines and measuring their wavelengths and intensities. Spectrometers may operate over a wide range of non-optical wavelengths, from gamma rays and X-rays into the far infrared. If the instrument is designed to measure the spectrum on an absolute scale rather than a relative one, then it is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gran Telescopio Canarias
The Gran Telescopio Canarias (GranTeCan or GTC) is a reflecting telescope located at the Roque de los Muchachos Observatory on the island of La Palma, in the Canaries, Spain. It is the world's largest single-aperture optical telescope. Construction of the telescope took seven years and cost €130 million. Its installation was hampered by weather conditions and the logistical difficulties of transporting equipment to such a remote location. First light was achieved in 2007 and scientific observations began in 2009. The GTC Project is a partnership formed by several institutions from Spain and Mexico, the University of Florida, the National Autonomous University of Mexico, and the Instituto de Astrofísica de Canarias (IAC). Planning for the construction of the telescope, which started in 1987, involved more than 1,000 people from 100 companies. The division of telescope time reflects the structure of its financing: 90% Spain, 5% Mexico and 5% the University of Florida. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
OTELO
{{unreferenced, date=January 2019 Otelo was the Office of the Telecommunications Ombudsman in the United Kingdom, superseded by Ombudsman Services. The organisation dealt with complaints about: * The way in which mobile and fixed phones, faxes and internet service are provided. * Certain services such as Short Messaging Service Short Message/Messaging Service, commonly abbreviated as SMS, is a text messaging service component of most telephone, Internet and mobile device systems. It uses standardized communication protocols that let mobile devices exchange short text ...s (SMS or texting), voice mail and call forwarding * Services and products for people with disabilities, such as text relay (an operator service that translates voice to text and text to voice) and free directory enquiries External linksOmbudsman Services website Ombudsmen in the United Kingdom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spectroscopy
Spectroscopy is the field of study that measures and interprets the electromagnetic spectra that result from the interaction between electromagnetic radiation and matter as a function of the wavelength or frequency of the radiation. Matter waves and acoustic waves can also be considered forms of radiative energy, and recently gravitational waves have been associated with a spectral signature in the context of the Laser Interferometer Gravitational-Wave Observatory (LIGO) In simpler terms, spectroscopy is the precise study of color as generalized from visible light to all bands of the electromagnetic spectrum. Historically, spectroscopy originated as the study of the wavelength dependence of the absorption by gas phase matter of visible light dispersed by a prism. Spectroscopy, primarily in the electromagnetic spectrum, is a fundamental exploratory tool in the fields of astronomy, chemistry, materials science, and physics, allowing the composition, physical structure and e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
FWHM
In a distribution, full width at half maximum (FWHM) is the difference between the two values of the independent variable at which the dependent variable is equal to half of its maximum value. In other words, it is the width of a spectrum curve measured between those points on the ''y''-axis which are half the maximum amplitude. Half width at half maximum (HWHM) is half of the FWHM if the function is symmetric. The term full duration at half maximum (FDHM) is preferred when the independent variable is time. FWHM is applied to such phenomena as the duration of pulse waveforms and the spectral width of sources used for optical communications and the resolution of spectrometers. The convention of "width" meaning "half maximum" is also widely used in signal processing to define bandwidth as "width of frequency range where less than half the signal's power is attenuated", i.e., the power is at least half the maximum. In signal processing terms, this is at most −3 dB of attenuatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telescope
A telescope is a device used to observe distant objects by their emission, absorption, or reflection of electromagnetic radiation. Originally meaning only an optical instrument using lenses, curved mirrors, or a combination of both to observe distant objects, the word ''telescope'' now refers to a wide range of instruments capable of detecting different regions of the electromagnetic spectrum, and in some cases other types of detectors. The first known practical telescopes were refracting telescopes with glass lenses and were invented in the Netherlands at the beginning of the 17th century. They were used for both terrestrial applications and astronomy. The reflecting telescope, which uses mirrors to collect and focus light, was invented within a few decades of the first refracting telescope. In the 20th century, many new types of telescopes were invented, including radio telescopes in the 1930s and infrared telescopes in the 1960s. Etymology The word ''telescope'' was coin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
