{"id":13,"date":"2015-05-29T19:26:21","date_gmt":"2015-05-29T19:26:21","guid":{"rendered":"http:\/\/jwst.astro.umontreal.ca\/?page_id=13"},"modified":"2024-09-03T15:37:53","modified_gmt":"2024-09-03T19:37:53","slug":"niriss-performance","status":"publish","type":"page","link":"https:\/\/jwst.astro.umontreal.ca\/?page_id=13","title":{"rendered":"NIRISS"},"content":{"rendered":"<p><strong>\u00a0<\/strong>The Near Infrared Imager and Slitless Spectrograph supports four observing modes: SOSS, AMI, WFSS and Imaging.<\/p>\n<ul>\n<li><strong>SOSS<\/strong> &#8211; <a href=\"https:\/\/jwst.astro.umontreal.ca\/?page_id=51\">Single Object Slit-Less Spectroscopy<\/a><\/li>\n<li><strong>WFSS<\/strong> &#8211; <a href=\"https:\/\/jwst.astro.umontreal.ca\/?page_id=641\">Wide Field Silt-Less Spectroscopy<\/a><\/li>\n<li><strong>AMI<\/strong> &#8211; <a href=\"https:\/\/jwst.astro.umontreal.ca\/?page_id=57\">Aperture Masking Interferometry<\/a><\/li>\n<li><strong>Imaging<\/strong> &#8211; <a href=\"https:\/\/jwst.astro.umontreal.ca\/?page_id=26\">Imaging<\/a> for parallel observations with another JWST instrument &#8211; not yet supported<\/li>\n<\/ul>\n\n<table id=\"tablepress-7\" class=\"tablepress tablepress-id-7\">\n<thead>\n<tr class=\"row-1\">\n\t<th class=\"column-1\">Observing<br \/>\nMode<\/th><th class=\"column-2\">Use<br \/>\nCase<\/th><th class=\"column-3\">Pupil<br \/>\nWheel<\/th><th class=\"column-4\">Filter<br \/>\nWheel<\/th><th class=\"column-5\">Spectral<br \/>\nRange<\/th><th class=\"column-6\">Resolving<br \/>\nPower<\/th><th class=\"column-7\">Characteristics<\/th>\n<\/tr>\n<\/thead>\n<tbody class=\"row-striping row-hover\">\n<tr class=\"row-2\">\n\t<td class=\"column-1\"><a href=\"http:\/\/jwst.astro.umontreal.ca\/?page_id=51\">SOSS<\/a><\/td><td class=\"column-2\">Time Series Observations (Exoplanet Transit Spectroscopy)<\/td><td class=\"column-3\">GR700XD<\/td><td class=\"column-4\">CLEAR (Slitless)<\/td><td class=\"column-5\">1st Order: <br \/>\n0.85-2.80 um<br \/>\n2nd Order: <br \/>\n0.60-1.40 um<\/td><td class=\"column-6\">1st Order: 650 @ 1.25 um<br \/>\n<\/td><td class=\"column-7\">Saturation Limiting Magnitudes:<br \/>\nSUBSTRIP96: J>6.3<br \/>\nSUBSTRIP256: J>8.1<br \/>\nFULLFRAME: J>8.9<\/td>\n<\/tr>\n<tr class=\"row-3\">\n\t<td class=\"column-1\"><a href=\"http:\/\/jwst.astro.umontreal.ca\/?page_id=57\">AMI<\/a><\/td><td class=\"column-2\">High Angular Resolution Imaging<\/td><td class=\"column-3\">NRM - 7 holes<\/td><td class=\"column-4\">F277W, F380M,<br \/>\nF430M or F480M<\/td><td class=\"column-5\">-<\/td><td class=\"column-6\">-<\/td><td class=\"column-7\">Contrasts <8-9 mag between 0.1'' and 0.4''<\/td>\n<\/tr>\n<tr class=\"row-4\">\n\t<td class=\"column-1\"><a href=\"http:\/\/jwst.astro.umontreal.ca\/?page_id=641\">WFSS<\/a><\/td><td class=\"column-2\">Low Resolving Power Slitless Spectroscopy<\/td><td class=\"column-3\">GR150C or GR150R<\/td><td class=\"column-4\">F090W, F115W, F140M, F150W, F158M or F200W<\/td><td class=\"column-5\">Set by blocking filter (0.8-2.2 um)<\/td><td class=\"column-6\">1st Order: 140 @ 1.3 um<\/td><td class=\"column-7\">Two grisms oriented at 90 degrees to mitigate contamination<\/td>\n<\/tr>\n<tr class=\"row-5\">\n\t<td class=\"column-1\"><a href=\"http:\/\/jwst.astro.umontreal.ca\/?page_id=26\">Imaging<\/a><\/td><td class=\"column-2\">Currently only supported as part of the WFSS direct image observations.<\/td><td class=\"column-3\">F090W, F115W, F140M, F150W, F158M, F200W <br \/>\nor CLEARP<\/td><td class=\"column-4\">F277W, F356W, F380M, F430M, F444W, F480M or CLEAR<\/td><td class=\"column-5\">-<\/td><td class=\"column-6\">-<\/td><td class=\"column-7\">FOV: 2.2' x 2.2'<br \/>\nPixel Scale: 65 mas <\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<!-- #tablepress-7 from cache -->\n<p>The <a href=\"https:\/\/jwst.astro.umontreal.ca\/?page_id=51\">SOSS mode<\/a> was designed to enable 0.6-2.8 microns low resolving power (R=700) exoplanet transit spectroscopy. The slit-less spectrograph uses a cross-dispersed grism in first and second orders, a weak cylindrical lens to defocus the trace to 23 pixels in the spatial direction and detector subarrays to target bright objects (6.3&lt;J&lt;12).<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-616 aligncenter\" src=\"https:\/\/jwst.astro.umontreal.ca\/wp-content\/uploads\/ModesTraces_inverted.png\" alt=\"ModesTraces_inverted\" width=\"900\" height=\"185\" srcset=\"https:\/\/jwst.astro.umontreal.ca\/wp-content\/uploads\/ModesTraces_inverted.png 2087w, https:\/\/jwst.astro.umontreal.ca\/wp-content\/uploads\/ModesTraces_inverted-300x62.png 300w, https:\/\/jwst.astro.umontreal.ca\/wp-content\/uploads\/ModesTraces_inverted-768x158.png 768w, https:\/\/jwst.astro.umontreal.ca\/wp-content\/uploads\/ModesTraces_inverted-1024x211.png 1024w\" sizes=\"auto, (max-width: 900px) 100vw, 900px\" \/><\/p>\n<p>The <a href=\"https:\/\/jwst.astro.umontreal.ca\/?page_id=641\">WFSS mode<\/a> was designed to obtain low-resolving power (R=150) slit-less spectra of a large amount of targets simultaneously within the 2.2&#8217;x2.2&#8242; field of view of NIRISS. There is a choice between two grisms producing spectra at orthogonal angles to each other to mitigate contamination in crowded fields. Blocking filters determine the wavelength coverage (0.8-2.2 microns).<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" width=\"300\" height=\"300\" class=\"size-medium wp-image-620 alignnone\" src=\"https:\/\/jwst.astro.umontreal.ca\/wp-content\/uploads\/CLASH_gr150horiz-300x300.png\" alt=\"CLASH_gr150horiz\" srcset=\"https:\/\/jwst.astro.umontreal.ca\/wp-content\/uploads\/CLASH_gr150horiz-300x300.png 300w, https:\/\/jwst.astro.umontreal.ca\/wp-content\/uploads\/CLASH_gr150horiz-150x150.png 150w, https:\/\/jwst.astro.umontreal.ca\/wp-content\/uploads\/CLASH_gr150horiz-640x640.png 640w, https:\/\/jwst.astro.umontreal.ca\/wp-content\/uploads\/CLASH_gr150horiz.png 653w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><img loading=\"lazy\" decoding=\"async\" width=\"300\" height=\"300\" class=\"size-medium wp-image-619 alignnone\" src=\"https:\/\/jwst.astro.umontreal.ca\/wp-content\/uploads\/CLASH_gr150verti-300x300.png\" alt=\"CLASH_gr150verti\" srcset=\"https:\/\/jwst.astro.umontreal.ca\/wp-content\/uploads\/CLASH_gr150verti-300x300.png 300w, https:\/\/jwst.astro.umontreal.ca\/wp-content\/uploads\/CLASH_gr150verti-150x150.png 150w, https:\/\/jwst.astro.umontreal.ca\/wp-content\/uploads\/CLASH_gr150verti-640x640.png 640w, https:\/\/jwst.astro.umontreal.ca\/wp-content\/uploads\/CLASH_gr150verti.png 660w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/p>\n<p><a href=\"https:\/\/jwst.astro.umontreal.ca\/?page_id=57\">AMI<\/a> is a high angular resolution imaging mode making use of a non-redundant mask (7 holes in the pupil) to produce interferograms. This mode allows to peer to inner working angles smaller (0.1&#8243; &#8211; 0.4&#8243;) than other types of imaging with JWST, albeit at shallower contrasts of 8-9 magnitudes near 4 microns.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" width=\"300\" height=\"212\" class=\"size-medium wp-image-622 alignnone\" src=\"https:\/\/jwst.astro.umontreal.ca\/wp-content\/uploads\/NRM_mask-300x212.png\" alt=\"NRM_mask\" srcset=\"https:\/\/jwst.astro.umontreal.ca\/wp-content\/uploads\/NRM_mask-300x212.png 300w, https:\/\/jwst.astro.umontreal.ca\/wp-content\/uploads\/NRM_mask.png 503w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-621 size-medium alignnone\" src=\"https:\/\/jwst.astro.umontreal.ca\/wp-content\/uploads\/binaire-300x293.png\" alt=\"binaire\" width=\"300\" height=\"293\" srcset=\"https:\/\/jwst.astro.umontreal.ca\/wp-content\/uploads\/binaire-300x293.png 300w, https:\/\/jwst.astro.umontreal.ca\/wp-content\/uploads\/binaire-768x749.png 768w, https:\/\/jwst.astro.umontreal.ca\/wp-content\/uploads\/binaire.png 851w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/p>\n<p>&nbsp;<\/p>\n<p>&nbsp;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u00a0The Near Infrared Imager and Slitless Spectrograph supports four observing modes: SOSS, AMI, WFSS and Imaging. SOSS &#8211; Single Object Slit-Less Spectroscopy WFSS &#8211; Wide Field Silt-Less Spectroscopy AMI &#8211; Aperture Masking Interferometry Imaging &#8211; Imaging for parallel&#8230; <a class=\"read-more\" href=\"https:\/\/jwst.astro.umontreal.ca\/?page_id=13\">Read More<\/a><\/p>\n","protected":false},"author":3,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"template-full.php","meta":{"footnotes":""},"class_list":["post-13","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/jwst.astro.umontreal.ca\/index.php?rest_route=\/wp\/v2\/pages\/13","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/jwst.astro.umontreal.ca\/index.php?rest_route=\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/jwst.astro.umontreal.ca\/index.php?rest_route=\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/jwst.astro.umontreal.ca\/index.php?rest_route=\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/jwst.astro.umontreal.ca\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=13"}],"version-history":[{"count":19,"href":"https:\/\/jwst.astro.umontreal.ca\/index.php?rest_route=\/wp\/v2\/pages\/13\/revisions"}],"predecessor-version":[{"id":1504,"href":"https:\/\/jwst.astro.umontreal.ca\/index.php?rest_route=\/wp\/v2\/pages\/13\/revisions\/1504"}],"wp:attachment":[{"href":"https:\/\/jwst.astro.umontreal.ca\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=13"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}