{"id":188,"date":"2019-06-14T19:24:20","date_gmt":"2019-06-14T19:24:20","guid":{"rendered":"https:\/\/www.tvcomm.co.uk\/g7izu\/?page_id=188"},"modified":"2025-06-02T10:11:09","modified_gmt":"2025-06-02T09:11:09","slug":"neutron-monitors","status":"publish","type":"page","link":"https:\/\/www.tvcomm.co.uk\/g7izu\/welcome\/neutron-monitors\/","title":{"rendered":"Neutron Monitors"},"content":{"rendered":"<div class=\"wp-block-image\">\n<figure class=\"aligncenter is-resized\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"318\" src=\"https:\/\/www.tvcomm.co.uk\/g7izu\/wp-content\/uploads\/2019\/09\/solar_cycles_1965-2020-1024x318.jpg\" alt=\"\" class=\"wp-image-563\" style=\"width:744px;height:231px\" srcset=\"https:\/\/www.tvcomm.co.uk\/g7izu\/wp-content\/uploads\/2019\/09\/solar_cycles_1965-2020-1024x318.jpg 1024w, https:\/\/www.tvcomm.co.uk\/g7izu\/wp-content\/uploads\/2019\/09\/solar_cycles_1965-2020-300x93.jpg 300w, https:\/\/www.tvcomm.co.uk\/g7izu\/wp-content\/uploads\/2019\/09\/solar_cycles_1965-2020-768x239.jpg 768w, https:\/\/www.tvcomm.co.uk\/g7izu\/wp-content\/uploads\/2019\/09\/solar_cycles_1965-2020.jpg 2048w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><figcaption class=\"wp-element-caption\"> Five solar cycles of Sunspots, Cosmic Rays and F10.7 Radio Flux&#8230; Calm before the storm. <br>Image courtesy <a rel=\"noreferrer noopener\" href=\"https:\/\/twitter.com\/leamonrj\" target=\"_blank\">@leamonrj<\/a> <\/figcaption><\/figure>\n<\/div>\n\n\n<figure class=\"wp-block-image\"><img decoding=\"async\" src=\"http:\/\/cosmicrays.oulu.fi\/webform\/monitor.gif\" alt=\"\"\/><\/figure>\n\n\n\n<p>Real-time Oulu NM count rate, updated every five minutes.<br>Data for the last 24-hr is PRELIMINARY<br>This is the neutron monitor at Oulu, Finland (<a href=\"http:\/\/cosmicrays.oulu.fi\/\" target=\"_blank\" rel=\"noreferrer noopener\">link<\/a>) provided by&nbsp;<a href=\"http:\/\/www.sgo.fi\/\">Sodankyla Geophysical Observatory&nbsp;<\/a><\/p>\n\n\n\n<p>Link to:&nbsp;<a href=\"https:\/\/gle.oulu.fi\/#\/\" target=\"_blank\" rel=\"noreferrer noopener\">Oulu Ground Level Event (GLE) Database<\/a><\/p>\n\n\n\n<p>Neutron Monitor at<br><a href=\"http:\/\/cosray.phys.uoa.gr\/index.php\/data\/nm-plots\" target=\"_blank\" rel=\"noreferrer noopener\">National and Kapodistrian University of Athens<\/a><\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter\"><img decoding=\"async\" src=\"http:\/\/swe.ssa.esa.int\/DOCS\/portal_images\/at_sl_aviation_doserate.gif?1552240066357\" alt=\"\"\/><\/figure>\n<\/div>\n\n\n<p><a href=\"https:\/\/www.seibersdorf-laboratories.at\/en\/products\/ionizing-radiation\/dosimetry\/avidos\/what-is-avidos\">Seibersdorf Laboroatories<\/a> Effective Radiation Dose Rate (8 altitudes)<br><\/p>\n\n\n\n<hr class=\"wp-block-separator has-css-opacity\"\/>\n\n\n\n<p><strong>What is a Neutron Monitor?<\/strong><\/p>\n\n\n\n<p>A neutron monitor is an instrument that measures the number of high-energy particles impacting Earth from space.<\/p>\n\n\n\n<p>For historical reasons these particles, mostly protons and helium nuclei, are called \u201ccosmic rays.\u201d Because the intensity of cosmic rays hitting Earth is not uniform, it is important to place neutron monitors at multiple locations in order to form a complete picture of cosmic rays in space.<\/p>\n\n\n\n<p>Cosmic ray rates are affected by solar wind strength and density, and therefore CMEs can have a major effect when they \u201csweep away\u201d some of the neutrons within the area of the earth\u2019s magnetic field. The first image below shows the effect of a CME impacting earth on 2017-07-16 following an M1.4 (semi) earth-directed solar flare. This is called a \u201cForbush Decrease\u201d. Cosmic&nbsp;ray bursts are caused by supernovae and other galactic events.<\/p>\n\n\n\n<p>The second image shows a Forbush decrease following an X9 flare and earth-directed CME on 2017-09-07. It also shows a minor \u201cGround Level Event\u201d where protons have reached ground level following a large X8.3 flare (from the same sunspot group). These events can cause an increase in radiation dose particularly for high altitude flyers especially flying over polar routes.<\/p>\n\n\n\n<p>For further very detailed background information\u00a0<a href=\"http:\/\/neutronm.bartol.udel.edu\/listen\/main.html\" target=\"_blank\" rel=\"noreferrer noopener\">see here<\/a>. The following graphic illustrates increases and decreases in neutron rates caused by solar flares and CMEs. It is not live data.<\/p>\n\n\n\n<figure class=\"wp-block-image\"><a href=\"http:\/\/tvcomm.co.uk\/g7izu\/wp-content\/uploads\/2017\/07\/nutron_cme1.jpg\"><img loading=\"lazy\" decoding=\"async\" width=\"611\" height=\"429\" src=\"https:\/\/www.tvcomm.co.uk\/g7izu\/wp-content\/uploads\/2019\/06\/neutrons_gle.jpg\" alt=\"\" class=\"wp-image-244\" srcset=\"https:\/\/www.tvcomm.co.uk\/g7izu\/wp-content\/uploads\/2019\/06\/neutrons_gle.jpg 611w, https:\/\/www.tvcomm.co.uk\/g7izu\/wp-content\/uploads\/2019\/06\/neutrons_gle-300x211.jpg 300w\" sizes=\"auto, (max-width: 611px) 100vw, 611px\" \/><\/a><\/figure>\n\n\n\n<p>*<\/p>\n\n\n\n<p><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Real-time Oulu NM count rate, updated every five minutes.Data for the last 24-hr is PRELIMINARYThis is the neutron monitor at Oulu, Finland (link) provided by&nbsp;Sodankyla Geophysical Observatory&nbsp; Link to:&nbsp;Oulu Ground Level Event (GLE) Database Neutron Monitor atNational and Kapodistrian University of Athens Seibersdorf Laboroatories Effective Radiation Dose Rate (8 altitudes) What is a Neutron Monitor? [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":4,"menu_order":30,"comment_status":"closed","ping_status":"closed","template":"","meta":{"ngg_post_thumbnail":0,"footnotes":""},"class_list":["post-188","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.tvcomm.co.uk\/g7izu\/wp-json\/wp\/v2\/pages\/188","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.tvcomm.co.uk\/g7izu\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www.tvcomm.co.uk\/g7izu\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www.tvcomm.co.uk\/g7izu\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.tvcomm.co.uk\/g7izu\/wp-json\/wp\/v2\/comments?post=188"}],"version-history":[{"count":17,"href":"https:\/\/www.tvcomm.co.uk\/g7izu\/wp-json\/wp\/v2\/pages\/188\/revisions"}],"predecessor-version":[{"id":2497,"href":"https:\/\/www.tvcomm.co.uk\/g7izu\/wp-json\/wp\/v2\/pages\/188\/revisions\/2497"}],"up":[{"embeddable":true,"href":"https:\/\/www.tvcomm.co.uk\/g7izu\/wp-json\/wp\/v2\/pages\/4"}],"wp:attachment":[{"href":"https:\/\/www.tvcomm.co.uk\/g7izu\/wp-json\/wp\/v2\/media?parent=188"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}