{"id":70,"date":"2022-07-03T10:13:03","date_gmt":"2022-07-03T10:13:03","guid":{"rendered":"https:\/\/observatory.haifa.ac.il\/?page_id=70"},"modified":"2022-09-11T18:38:08","modified_gmt":"2022-09-11T18:38:08","slug":"polarimetry","status":"publish","type":"page","link":"https:\/\/observatory.haifa.ac.il\/?page_id=70","title":{"rendered":"polarimetry"},"content":{"rendered":"\t\t<div data-elementor-type=\"wp-page\" data-elementor-id=\"70\" class=\"elementor elementor-70\">\n\t\t\t\t\t\t\t\t\t<section class=\"elementor-section elementor-top-section elementor-element elementor-element-33247e8 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"33247e8\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t<div class=\"elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-1a6d5e4\" data-id=\"1a6d5e4\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-widget-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-element elementor-element-7a30eca elementor-widget elementor-widget-text-editor\" data-id=\"7a30eca\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t<style>\/*! elementor - v3.7.4 - 31-08-2022 *\/\n.elementor-widget-text-editor.elementor-drop-cap-view-stacked .elementor-drop-cap{background-color:#818a91;color:#fff}.elementor-widget-text-editor.elementor-drop-cap-view-framed .elementor-drop-cap{color:#818a91;border:3px solid;background-color:transparent}.elementor-widget-text-editor:not(.elementor-drop-cap-view-default) .elementor-drop-cap{margin-top:8px}.elementor-widget-text-editor:not(.elementor-drop-cap-view-default) .elementor-drop-cap-letter{width:1em;height:1em}.elementor-widget-text-editor .elementor-drop-cap{float:left;text-align:center;line-height:1;font-size:50px}.elementor-widget-text-editor .elementor-drop-cap-letter{display:inline-block}<\/style>\t\t\t\t<h2>quasar polarimetry<\/h2><div>Valuable information about the structure and physics of active galactic nuclei (a.k.a. quasars) can be obtained by studying their polarized emission, and in particular its time-variation. Polarized emission can relate to the emission mechanism of the quasar (e.g., due to the gyration of electrons in magnetic field, as in radio-loud quasars) or be the result of scattering of non-polarized light by asymmetric geometrical structures (clearly, both effects can work in tandem). In addition to that, dust particles between us and the source can lead to further polarization due to grain alignment in the interstellar medium, yet this effect may be mitigated and is not expected to lead to time-variation over human lifetimes. The inner engines of quasars are thought to have inherent (disk\/bowl-like) asymmetry, with both free electrons and dust acting as possible reflectors. Therefore, the study of polarized light in (radio-quiet) quasars can enhance our understanding of their inner regions.<\/div><p>\u00a0<\/p><p>We employ a novel technique, which has recently become accessible whereby micro-polarizers are installed above individual pixels on the (CMOS) detector.<\/p>\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<section class=\"elementor-section elementor-inner-section elementor-element elementor-element-b708dd0 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"b708dd0\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t<div class=\"elementor-column elementor-col-50 elementor-inner-column elementor-element elementor-element-41b61ca\" data-id=\"41b61ca\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-widget-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-element elementor-element-9ce6058 elementor-widget elementor-widget-image\" data-id=\"9ce6058\" data-element_type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t<style>\/*! elementor - v3.7.4 - 31-08-2022 *\/\n.elementor-widget-image{text-align:center}.elementor-widget-image a{display:inline-block}.elementor-widget-image a img[src$=\".svg\"]{width:48px}.elementor-widget-image img{vertical-align:middle;display:inline-block}<\/style>\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"1013\" height=\"1024\" src=\"https:\/\/observatory.haifa.ac.il\/wp-content\/uploads\/2022\/09\/micropolw-1013x1024.jpg\" class=\"attachment-large size-large\" alt=\"\" srcset=\"https:\/\/observatory.haifa.ac.il\/wp-content\/uploads\/2022\/09\/micropolw-1013x1024.jpg 1013w, https:\/\/observatory.haifa.ac.il\/wp-content\/uploads\/2022\/09\/micropolw-297x300.jpg 297w, https:\/\/observatory.haifa.ac.il\/wp-content\/uploads\/2022\/09\/micropolw-768x776.jpg 768w, https:\/\/observatory.haifa.ac.il\/wp-content\/uploads\/2022\/09\/micropolw.jpg 1330w\" sizes=\"auto, (max-width: 1013px) 100vw, 1013px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">From Vorobiev et al. 2018 (PASP, 130:064501)<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t<div class=\"elementor-column elementor-col-50 elementor-inner-column elementor-element elementor-element-baf3bad\" data-id=\"baf3bad\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-widget-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-element elementor-element-ce9f5f2 elementor-widget elementor-widget-text-editor\" data-id=\"ce9f5f2\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<div class=\"page\" title=\"Page 5\"><div class=\"layoutArea\"><div class=\"column\"><p>Micrograph from a scanning electron microscope of a micropolarizer array \u201csuperpixel.\u201d The superpixel consists of 4 individual pixels, each or which is covered by a polarizers that transmits light with a given polarization. Stokes arithmetic of the flux in the 4 pixels can reveal the linear polarization angle and percentage for light in the super pixel. From Vorobiev et al. (2018).<\/p><\/div><\/div><\/div>\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t<\/div>\n\t\t","protected":false},"excerpt":{"rendered":"<p>quasar polarimetry Valuable information about the structure and physics of active galactic nuclei (a.k.a. quasars) can be obtained by studying their polarized emission, and in particular its time-variation. Polarized emission can relate to the emission mechanism of the quasar (e.g., due to the gyration of electrons in magnetic field, as in radio-loud quasars) or be [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"elementor_header_footer","meta":{"footnotes":""},"class_list":["post-70","page","type-page","status-publish","hentry","entry"],"_links":{"self":[{"href":"https:\/\/observatory.haifa.ac.il\/index.php?rest_route=\/wp\/v2\/pages\/70","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/observatory.haifa.ac.il\/index.php?rest_route=\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/observatory.haifa.ac.il\/index.php?rest_route=\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/observatory.haifa.ac.il\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/observatory.haifa.ac.il\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=70"}],"version-history":[{"count":21,"href":"https:\/\/observatory.haifa.ac.il\/index.php?rest_route=\/wp\/v2\/pages\/70\/revisions"}],"predecessor-version":[{"id":532,"href":"https:\/\/observatory.haifa.ac.il\/index.php?rest_route=\/wp\/v2\/pages\/70\/revisions\/532"}],"wp:attachment":[{"href":"https:\/\/observatory.haifa.ac.il\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=70"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}