{"id":3951,"date":"2025-05-26T15:47:18","date_gmt":"2025-05-26T15:47:18","guid":{"rendered":"http:\/\/astri.me.oa-brera.inaf.it\/?page_id=3951"},"modified":"2025-06-06T14:59:10","modified_gmt":"2025-06-06T14:59:10","slug":"new-astrofisica-delle-altissime-energie","status":"publish","type":"page","link":"https:\/\/www.astri.inaf.it\/index.php\/prova\/new-astrofisica-delle-altissime-energie\/","title":{"rendered":"Astrofisica delle altissime energie"},"content":{"rendered":"\n<style type=\"text\/css\" data-created_by=\"avia_inline_auto\" id=\"style-css-av-mbi2wwpv-3db37bde8646a9e95339bcbaa9821c55\">\n#top .av-special-heading.av-mbi2wwpv-3db37bde8646a9e95339bcbaa9821c55{\npadding-bottom:10px;\n}\nbody .av-special-heading.av-mbi2wwpv-3db37bde8646a9e95339bcbaa9821c55 .av-special-heading-tag .heading-char{\nfont-size:25px;\n}\n.av-special-heading.av-mbi2wwpv-3db37bde8646a9e95339bcbaa9821c55 .av-subheading{\nfont-size:15px;\n}\n<\/style>\n<div  class='av-special-heading av-mbi2wwpv-3db37bde8646a9e95339bcbaa9821c55 av-special-heading-h2 blockquote modern-quote  avia-builder-el-0  el_before_av_one_half  avia-builder-el-first '><h2 class='av-special-heading-tag '  itemprop=\"headline\"  >Astrofisica delle altissime energie<\/h2><div class=\"special-heading-border\"><div class=\"special-heading-inner-border\"><\/div><\/div><\/div>\n<div  class='flex_column av-7u8enj-c35f7ff689a4f3efeea293d21847de0b av_one_half  avia-builder-el-1  el_after_av_heading  el_before_av_one_half  first flex_column_div  '     ><style type=\"text\/css\" data-created_by=\"avia_inline_auto\" id=\"style-css-av-mbi3duuf-f286954013045a90e37e9ece109753cd\">\n.avia-image-container.av-mbi3duuf-f286954013045a90e37e9ece109753cd img.avia_image{\nbox-shadow:none;\n}\n.avia-image-container.av-mbi3duuf-f286954013045a90e37e9ece109753cd .av-image-caption-overlay-center{\ncolor:#ffffff;\n}\n<\/style>\n<div  class='avia-image-container av-mbi3duuf-f286954013045a90e37e9ece109753cd av-styling- avia-align-center  avia-builder-el-2  avia-builder-el-no-sibling  av-has-copyright av-copyright-always'   itemprop=\"image\" itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/ImageObject\" ><div class=\"avia-image-container-inner\"><div class=\"avia-image-overlay-wrap\"><img decoding=\"async\" fetchpriority=\"high\" class='wp-image-4106 avia-img-lazy-loading-not-4106 avia_image ' src=\"https:\/\/www.astri.inaf.it\/wp-content\/uploads\/2025\/06\/Cherenkov_light-1.png\" alt='the figure shows the development of a particle shower in the upper atmosphere and the production of Cherenkov radiation' title='Cherenkov_light'  height=\"300\" width=\"230\"  itemprop=\"thumbnailUrl\"  \/><\/div><small class=\"avia-copyright\">Credits: Weekes, T.C, talk at the 2012 Fermi Summer School<\/small><\/div><\/div><\/div>\n<div  class='flex_column av-591fbz-c8bd6c3669e4d61bd763663bbf72c903 av_one_half  avia-builder-el-3  el_after_av_one_half  el_before_av_one_half  flex_column_div  '     ><section  class='av_textblock_section av-mbi3ep57-531b8a5ed6894fc3bac01960f4bc52b0 '   itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/CreativeWork\" ><div class='avia_textblock'  itemprop=\"text\" ><h3><strong>Tecnica<\/strong><\/h3>\n<p>Quando un fotone di altissima energia (VHE &#8211; very high-energy), con un\u2019energia di circa 1 Tera-elettronvolt, colpisce l\u2019atmosfera terrestre, genera una cascata di particelle che a sua volta produce un lampo di radiazione Cherenkov della durata di 5\u201320 nanosecondi, nell\u2019intervallo di lunghezze d\u2019onda compreso tra 300 e 500 nanometri.<\/p>\n<p>La luce Cherenkov si diffonde in un cono che raggiunge un diametro di circa 100\u2013200 metri sulla superficie terrestre. Una rappresentazione schematica \u00e8 mostrata in questa figura\u00a0[<em>Crediti: <\/em><a href=\"https:\/\/fermi.gsfc.nasa.gov\/science\/mtgs\/summerschool\/2012\/week2\/ACT_Weekes.pdf\" target=\"_blank\" rel=\"noopener\"><em>Weekes, T.C, talk at the 2012 Fermi Summer School<\/em><\/a>].<\/p>\n<p>Questa luce viene riflessa dagli specchi del telescopio sul piano focale di una camera che la converte in fotoelettroni. Il segnale viene acquisito da un sistema di gestione dati e memorizzato in computer locali per l\u2019elaborazione successiva.<\/p>\n<\/div><\/section><\/div><div  class='flex_column av-4jbaa7-d1c925cd6c9af1f678ab7927e9040d8b av_one_half  avia-builder-el-5  el_after_av_one_half  el_before_av_one_half  first flex_column_div  column-top-margin'     ><section  class='av_textblock_section av-mbi3n2zm-6a1410b73fbc5717d2166acd7d6b328a '   itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/CreativeWork\" ><div class='avia_textblock'  itemprop=\"text\" ><p>Un miglioramento rilevante \u00e8 stato ottenuto adottando l\u2019approccio stereoscopico, come mostrato in questa figura\u00a0[<em>Crediti: <\/em><a href=\"https:\/\/arxiv.org\/abs\/1511.0046\" target=\"_blank\" rel=\"noopener\"><em>de Naurois M. and Mazin D., 2015., C.R. Physique 16, 610<\/em><\/a>].<\/p>\n<p>I vantaggi dell\u2019approccio a matrice (array) includono un miglioramento nella reiezione del fondo e nelle risoluzioni angolare ed energetica.<\/p>\n<p>Alle energie pi\u00f9 elevate (0.1\u2013100 Peta-elettronvolt), le cascate di particelle vengono convertite in radiazione Cherenkov tramite grandi serbatoi d\u2019acqua, in combinazione con altre matrici per la discriminazione del fondo. Questi sistemi sono chiamati array di campionamento di particelle (<em data-start=\"1778\" data-end=\"1804\">particle sampling arrays<\/em>, PSA).<\/p>\n<\/div><\/section><\/div><div  class='flex_column av-2idgyn-2b3df2e8c8f3446d061cea9c34c042ff av_one_half  avia-builder-el-7  el_after_av_one_half  el_before_av_textblock  flex_column_div  column-top-margin'     ><style type=\"text\/css\" data-created_by=\"avia_inline_auto\" id=\"style-css-av-mbi3nx9h-074400f75803ff1b5d28ff271d7ea8cd\">\n.avia-image-container.av-mbi3nx9h-074400f75803ff1b5d28ff271d7ea8cd img.avia_image{\nbox-shadow:none;\n}\n.avia-image-container.av-mbi3nx9h-074400f75803ff1b5d28ff271d7ea8cd .av-image-caption-overlay-center{\ncolor:#ffffff;\n}\n<\/style>\n<div  class='avia-image-container av-mbi3nx9h-074400f75803ff1b5d28ff271d7ea8cd av-styling- avia-align-center  avia-builder-el-8  avia-builder-el-no-sibling  av-has-copyright av-copyright-always'   itemprop=\"image\" itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/ImageObject\" ><div class=\"avia-image-container-inner\"><div class=\"avia-image-overlay-wrap\"><img decoding=\"async\" fetchpriority=\"high\" class='wp-image-4123 avia-img-lazy-loading-not-4123 avia_image ' src=\"https:\/\/www.astri.inaf.it\/wp-content\/uploads\/2025\/06\/stereoscopic.png\" alt='the figure shows how a stereoscopic system works and advantage of the stereoscopic approach to improve the source location accuracy' title='stereoscopic'  height=\"405\" width=\"1030\"  itemprop=\"thumbnailUrl\"  \/><\/div><small class=\"avia-copyright\">Credits: de Naurois M. and Mazin D., 2015., C.R. Physique 16, 610<\/small><\/div><\/div><\/div><\/p>\n<section  class='av_textblock_section av-mbi3pf5c-79a1de555b08e4fe498cc5cd63752c36 '   itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/CreativeWork\" ><div class='avia_textblock'  itemprop=\"text\" ><h3><strong>Array attualmente operativi<\/strong><\/h3>\n<p>Attualmente, sono operativi tre principali array Cherenkov atmosferici a immagine (IACTs): due nell\u2019emisfero Nord (<a href=\"https:\/\/magic.mppmu.mpg.de\/\" target=\"_blank\" rel=\"noopener\">MAGIC<\/a> &#038; <a href=\"https:\/\/veritas.sao.arizona.edu\/\" target=\"_blank\" rel=\"noopener\">VERITAS<\/a>) e uno nell\u2019emisfero sud (<a href=\"https:\/\/www.mpi-hd.mpg.de\/HESS\/\" target=\"_blank\" rel=\"noopener\">H.E.S.S.<\/a>). I tre principali PSA, invece, sono <a href=\"http:\/\/english.ihep.cas.cn\/lhaaso\/\" target=\"_blank\" rel=\"noopener\">LHAASO<\/a>, <a href=\"https:\/\/www.hawc-observatory.org\/\" target=\"_blank\" rel=\"noopener\">HAWC<\/a> e\u00a0<a href=\"https:\/\/www.icrr.u-tokyo.ac.jp\/em\/index.html\" target=\"_blank\" rel=\"noopener\">TIbet AS-\ud835\udfac<\/a>, tutti situati nell\u2019emisfero Nord.<\/p>\n<p>Le loro osservazioni hanno permesso di portare il numero di sorgenti conosciute a circa 350, a energie superiori a qualche decina di Giga-elettronvolt. Come si pu\u00f2 osservare in questa figura [<em>Crediti: <\/em><a href=\"https:\/\/www.tevcat.org\/\" target=\"_blank\" rel=\"noopener\"><em>https:\/\/www.tevcat.org\/<\/em><\/a><em>, <\/em><a href=\"https:\/\/indico.nucleares.unam.mx\/event\/4\/session\/40\/contribution\/378\/material\/paper\/0.pdf\" target=\"_blank\" rel=\"noopener\"><em>Wakely S.P. &#038; Horan D., 2008, ICRC, 3, 1341<\/em><\/a>], diverse classi di sorgenti sia galattiche che extragalattiche sono state rilevate dagli attuali IACT, con una larga frazione (circa il 30%) priva di una controparte nota, rendendo l\u2019astrofisica delle altissime energie un campo di indagine estremamente promettente.<\/p>\n<\/div><\/section>\n\n<style type=\"text\/css\" data-created_by=\"avia_inline_auto\" id=\"style-css-av-mbi3ttbt-fc7e038b777ee72b04b482dcbe5e3ab3\">\n.avia-image-container.av-mbi3ttbt-fc7e038b777ee72b04b482dcbe5e3ab3 img.avia_image{\nbox-shadow:none;\n}\n.avia-image-container.av-mbi3ttbt-fc7e038b777ee72b04b482dcbe5e3ab3 .av-image-caption-overlay-center{\ncolor:#ffffff;\n}\n<\/style>\n<div  class='avia-image-container av-mbi3ttbt-fc7e038b777ee72b04b482dcbe5e3ab3 av-styling- avia-align-center  avia-builder-el-10  el_after_av_textblock  avia-builder-el-last  av-has-copyright av-copyright-always'   itemprop=\"image\" itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/ImageObject\" ><div class=\"avia-image-container-inner\"><div class=\"avia-image-overlay-wrap\"><img decoding=\"async\" fetchpriority=\"high\" class='wp-image-4132 avia-img-lazy-loading-not-4132 avia_image ' src=\"https:\/\/www.astri.inaf.it\/wp-content\/uploads\/2025\/06\/GeV_sources.png\" alt='the figure shows the current population of sources detected above a few tens of GeV in the whole sky.' title='GeV_sources'  height=\"421\" width=\"1030\"  itemprop=\"thumbnailUrl\"  \/><\/div><small class=\"avia-copyright\">Credits: https:\/\/www.tevcat.org\/, Wakely S.P. &amp; Horan D., 2008, ICRC, 3, 1341<\/small><\/div><\/div>\n","protected":false},"excerpt":{"rendered":"","protected":false},"author":4,"featured_media":0,"parent":3930,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-3951","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.astri.inaf.it\/index.php\/wp-json\/wp\/v2\/pages\/3951","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.astri.inaf.it\/index.php\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www.astri.inaf.it\/index.php\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www.astri.inaf.it\/index.php\/wp-json\/wp\/v2\/users\/4"}],"replies":[{"embeddable":true,"href":"https:\/\/www.astri.inaf.it\/index.php\/wp-json\/wp\/v2\/comments?post=3951"}],"version-history":[{"count":36,"href":"https:\/\/www.astri.inaf.it\/index.php\/wp-json\/wp\/v2\/pages\/3951\/revisions"}],"predecessor-version":[{"id":5594,"href":"https:\/\/www.astri.inaf.it\/index.php\/wp-json\/wp\/v2\/pages\/3951\/revisions\/5594"}],"up":[{"embeddable":true,"href":"https:\/\/www.astri.inaf.it\/index.php\/wp-json\/wp\/v2\/pages\/3930"}],"wp:attachment":[{"href":"https:\/\/www.astri.inaf.it\/index.php\/wp-json\/wp\/v2\/media?parent=3951"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}