WFC3 Instrument Handbook for Cycle 24 . ... Wide Field Camera 3 Instrument Handbook for Cycle 24 > Chapter 8: Slitless Spectroscopy with WFC3 > 8.2 Slitless Spectroscopy with the UVIS G280 Grism . ... The circled spot shows the location of a direct image of the source obtained with a separate (undispersed) F300X filter exposure, but superposed on the grism image for illustrative purposes only. ... Figure 8.3: The absolute throughput of the G280 grism as a function of wavelength for the lowest orders. ...

Next: Order Definition Up: Echelle Reduction Method Previous: Retrieving demonstration and . ... That is the mapping between the space wavelength, spectral order and the space sample x , line y in the raw image. ... Sections and describe the solution of this mapping. The second step in the reduction, described in Section , is to estimate the image background. ... In the rest of this Section the algorithms used in each step of the reduction are described. ...

... The ARC echelle spectrograph records the entire visible and near-IR spectrum in one exposure on a 2048 x 2048 SITe CCD chip with 24 micron pixels, with a resolution of 30,000. (2.5 pixels) . ... CCD is a SITe TK2048E back illuminated CCD . CCD is a 2048 x 2048 pixel array . ... Field of View: Available slits (Observing Specialist installable): 1.6" x 1.6" , 1.6" x 3.2" (default), 1.6" x 4.7", 0.9" x 0.9" (pinhole) . ... 31.6 grooves/mm, blaze angle b = 63.5 deg (nominal), or tan b = 2 . ...

XMM-Newton Science Analysis System Page: 1 rgscombine August 16, 2005 Abstract Combines a list of spectrum les to create one combined spectrum le, and the corresponding list of response matrices and background spectrum, to create one nal response matrix and background spectrum le, for a paticular RGS instrument and spectral order. ... A list of response matrix les, as produced by rgsrmfgen or rgsproc. A list of background spectrum les as produced by rgsspectrum or rgsproc for TOTAL spectra. ...

... Instrument Status . Science Verification . ... CRIRES . ... SV observer shall submit their proposals using the Science Verification proposal template Proposers are asked to provide at least a short summary of the science goal, coordinates and magnitudes of GS and science target, a finding chart , the observing wavelength ID, as specified in appendix A of the UM and DIT, NDIT settings of science detectors as computed with the exposure time calculator (see below). ... with a 0.2 arcsec slit. ...

... The calibration of astrophysical spectra in wavelength based on calibration lamp data suffers from different kinds of uncertainties. Besides inaccuracies in the observational phase, common data reduction practice adds ``pixelation'' errors, due to the fact that the centering method does not use the correct PSF. These model mismatch errors depend, for a given feature, on the sub-pixel location of the line center (David & Verschueren, private communication). ...

... The spectrum is reversed left to right. ... Starting line IDs Line identification in order 26 (x reversed ) Channel Wavelength Calculated Discrepancy Line # 166.3593 8478.3584 8478.3613 0.0029 1 258.5106 8490.3066 8490.3213 0.0146 2 500.5818 8521.4385 8521.3926 -0.0459 3 912.9249 8573 ... 0.0547 4 1178.5211 8605.7764 8605.7803 0.0039 5 1299.3500 8620.4600 8620.4209 -0.0391 6 1698.4974 8667.9404 8667.9492 0.0088 7 line identification in order 34 (x reversed ) Channel Wavelength ...

The basic characteristics of the instrument are set by the aperture, focal length and resolution of the image forming lens, the dispersion of the spectrometer, and the sensitivity of the detector. ... The lens is internally focused, and maintains acceptable focus (2 pixels in the detector plane) over a typical spectral coverage of one grating setting. ... along the spatial dimension of a 25mm square detector in the final spectral image plane the 400mm lens is 3.2њ. ... Diffraction grating . ...

The optical scheme of the instrument is sketched in Figure 1 , it is designed to match the F/20 focal ratio of the TIRGO telescope. We have, following the optical path, the window of the dewar, the order sorting filter (not in figure), a field lens, in Calcium Floride, and the slit, in the focal plane of the telescope. ... The resolving power is (for first order of grating) of about 600 in the center of J band and 950 in the center of the K band, using a slit of two pixel (3.46 arcsec). ...

... The choice of the spectrograph design (Fig.2) is determined by the quantity R, the overall dimensions of the PF cage and the restrictions on the rigidity of the structure of the device. ... As the camera's objective a fast 4-lens aplanat is used having a focal distance F cam =140 mm and a relative aperture of 1:1.8, the resolution at the centre is no less than 80 gr/mm, that over the field at a distance of 3 mm from the edge along the frame ( ) diagonal is 35 gr/mm. ...

... An analysis of series of flat­field exposures obtained in echelle mode adds support to the view that the performance of an instrument should be monitored closely and described quantitatively. ... This may result in confusion about basic instru­ mental parameters, the precision of the set­up, the amount and distribution of calibration frames which are required and finally the assumptions on which the data reduction procedure should rely. ... The value for pure random noise is indicated 1). ...

... 8.633400E-4 1) This may be read into IDL using the procedure ucles_read, file , w, f file : string : : in : name of file containing data w : array : (2048, nord) : out : wavelengths for each order f : array : (2048, nord, narr) : out : fluxes in each array 2) The next step is to remove the gross continuum shape using the procedure ucles_norm, w, f, fn, fs w : array : (2048, nord) : in : wavelengths for each ... 3) Define a standard wavelength grid for the entire spectrum....

Next: Image Arithmetic - MATHS Up: Image Analysis Previous: Source Fitting and Positions . The task imsub allows you to extract out some region of one image and copy it to a new image. ... Input image . ... Output image . ... The task reorder enables you to reorder the axes of an image. ... The task regrid enables you to take an image, and regrid it via a cubic interpolation scheme on a new grid. ... In this simple example, we regrid the first two axes of an image via a template image. ...

... The project assumes creation of an international space observatory - the interferometer "Earth - Space - Space" in order to perform of astronomical investigations in millimeter, submillimeter and infrared regions with extremely high sensitivity (to a few nanoJanskies units of flux density in continuum spectrum) and extremely high angular resolution (to a parts of microsecond of arc or, possibly, nanosecond). ... radio-interferometric channels of the system "Space - Space", region 0.2 - 3 mm; . ...

HEAD 2011: Poster 10.05 Project Tanagra: Stellar Flares in Chandra High-Resolution Spectra Jennifer Posson-Brown, Vinay Kashyap, Steven Saar & Jeremy Drake (Harvard-Smithsonian Center for Astrophysics) Abstract We introduce Project Tanagra: Timing Analysis of Gratings Data, a uniform study of archival Chandra gratings observations of active l ow-mass coronal stars. ... See Kashyap et al. 2002, 2011 and Saar et al. 2011.) ... High resolution spectra from MEG and HEG first order, and ze roth order. ...

... Content Model: Optional list header (LH), followed by one or more list items (LI) . An unordered list typically is a bulleted list of items. ... Note: Some legacy documents may include headers or plain text before the first LI element. ... DIR lists are used to present lists of items containing up to 20 characters each. ... CLASS . ... The WRAP attribute is used for multicolumn lists. Use wrap=vert if you want to arrange the list items down the page before wrapping to the next column. ...

... Both sets of objective transmission gratings consist of hundreds of co-aligned facets mounted to supporting structures on 4 annuli (one for each of the four co-aligned mirror pairs) to intercept the x rays exiting the HRMA. ... The two sets of transmission gratings, attached to the mounting structure are shown in Figure . ... An individual facet has 0.43-m-thick gold grating bars with 50% filling factor and 9920- period, resulting in 1.15-/mm dispersion. The HRC-S is the primary LETG readout. ...

Static Fourier spectrometers are often used for spectral measurements of the ionosphere emissions. There are two main advantages of Fourier spectrometers (FS) - large geometric factor and high spectral resolution; these parameters are two orders better than for grating spectral instruments. ... In scanning Fourier spectrometer optical and electric modulation of signal is used to avoid this problem, for static Fourier spectrometer there are no such ways. ...

The Arecibo telescope is a versatile instrument with multiple receivers, backend processors, and telescope scanning modes. ... Observing modes are implemented at Arecibo through the Control Interface Module for Arecibo (CIMA). ... In this case, the observer is encouraged to submit a proposal for a new observing mode. ... Proposals for new observing modes will be evaluated by a technical review panel consisting of Arecibo technical and scientific staff. ... Flow chart. ...