\u00dcnl\u00fc Higgs par\u00e7ac\u0131\u011f\u0131n\u0131 bulan CERN deneyinde, Higgs par\u00e7ac\u0131\u011f\u0131n\u0131 bulmaktan farkl\u0131 bir i\u015f yapan LHCb grubu, bir ba\u015fka \u00f6nemli bulu\u015fa imza atm\u0131\u015f olabilir. Grup 7 Nisan 2014 tarihinde, arXiv (Cornell \u00dcniversitesi\u2019nin a\u00e7\u0131k makale sistemi) sitesinde egzotik bir par\u00e7ac\u0131\u011f\u0131 bulduklar\u0131n\u0131 a\u00e7\u0131klad\u0131.<\/p>\n
LHCb grubu, CERN\u2019deki b\u00fcy\u00fck hadron \u00e7arp\u0131\u015ft\u0131r\u0131c\u0131s\u0131 \u00fczerinde kurulmu\u015f olan 4 detekt\u00f6rden birini kullan\u0131yor. Higgs bozonunu bulduklar\u0131n\u0131 a\u00e7\u0131klayan ATLAS ve CMS gruplar\u0131 da, ayn\u0131 h\u0131zland\u0131r\u0131c\u0131 \u00fczerindeki ba\u015fka detekt\u00f6rleri kullan\u0131yorlar. Bulduklar\u0131 par\u00e7ac\u0131\u011f\u0131 \u00f6nemli yapan \u015fey, d\u00f6rtl\u00fc kuark sisteminden olu\u015ftu\u011funun d\u00fc\u015f\u00fcn\u00fclmesi.<\/p>\n
Kuarklar i\u00e7in \u201cmadde\u201dnin temel yap\u0131ta\u015flar\u0131 diyebiliriz. Proton ve n\u00f6tronlar 3\u2019l\u00fc ba\u011f yapan kuark sistemlerinden olu\u015fuyor. Onlar d\u0131\u015f\u0131nda 3\u2019l\u00fc ve 2\u2019li kuark yap\u0131l\u0131 bir\u00e7ok par\u00e7ac\u0131k oldu\u011funu biliyoruz. Ancak bu zamana kadar 4\u2019l\u00fc kuark sistemi olan hi\u00e7bir par\u00e7ac\u0131k bulunmad\u0131. Kuarklar\u0131n neden tek ba\u015flar\u0131na do\u011fada bulanamad\u0131\u011f\u0131n\u0131 bilsek de (renk hapsi) neden sadece 2\u2019li (mezonlar) veya 3\u2019l\u00fc (baryonlar) ba\u011f yap\u0131lar\u0131nda olduklar\u0131na dair tatmin edici bir fikrimiz yok.<\/p>\n
4\u2019l\u00fc kuark yap\u0131lar\u0131n\u0131n varl\u0131\u011f\u0131 uzun zamand\u0131r biliminsanlar\u0131 aras\u0131nda tart\u0131\u015f\u0131l\u0131yor ve varl\u0131klar\u0131 aran\u0131yor. Ancak 4\u2019l\u00fc sistemler i\u00e7in yap\u0131lmas\u0131 gereken hesaplar \u00e7ok karma\u015f\u0131k oldu\u011fu i\u00e7in bu zamana kadar hesaplar\u0131 yap\u0131p fikri test edebilen olmad\u0131. Maryland \u00dcniversitesi\u2019nden Thomas Cohen \u201cHen\u00fcz, bilgisayarlar teorinin (kuantum renk dinami\u011fi) temel prensiplerinden yola \u00e7\u0131k\u0131p, \u00e7\u00f6z\u00fcm yapabilecek kadar g\u00fc\u00e7l\u00fc de\u011fil\u201d diye belirtiyor. Bu, hen\u00fcz kimse fizik yasalar\u0131n\u0131n 4\u2019l\u00fc kuark yap\u0131lara izin verip vermedi\u011fini bilmiyor demek. Ancak bu yap\u0131lar\u0131 neden g\u00f6zlemlemedi\u011fimize dair kesin bir fikir de yok.<\/p>\n
G\u00f6zlemlendi\u011fi s\u00f6ylenen par\u00e7ac\u0131\u011f\u0131n ad\u0131 Z(4430)-. 4430 say\u0131s\u0131, par\u00e7ac\u0131\u011f\u0131n 4430 MeV k\u00fctlesi oldu\u011funu (yakla\u015f\u0131k olarak protonun 4 kat\u0131 a\u011f\u0131rl\u0131kta) ve elektron gibi negatif elektrik y\u00fck\u00fcne sahip oldu\u011funu belirtiyor. Z harfi ise tuhaf par\u00e7ac\u0131klar (strangeparticles) serisine verilen XYZ sistemlerinden hangisi oldu\u011funu s\u00f6yl\u00fcyor.<\/p>\n
Peki bu yap\u0131y\u0131 \u00f6zel k\u0131lan ne? Daha \u00f6ncesinde de belirtildi\u011fi gibi 2003\u2019e kadar bulunan y\u00fczlerce par\u00e7ac\u0131k ya 2\u2019li kuark ya da 3\u2019l\u00fc kuark yap\u0131s\u0131na sahipti. 2003\u2019de ise BELLE deneyi b\u00fcy\u00fck bir s\u00fcrpriz yapt\u0131 ve 4\u2019l\u00fc kuark yap\u0131s\u0131na benzeyen bir sistem bulundu\u011fu a\u00e7\u0131kland\u0131. Bu sistemler genellikle charmonium ve bottomonium denilen t\u0131ls\u0131m ve anti-t\u0131ls\u0131m veya alt ve ant-alt kuarklardan olu\u015fuyor. Ge\u00e7en baharda BESIII grubunun g\u00f6zlemledi\u011fini a\u00e7\u0131klad\u0131\u011f\u0131 ZC(3900)+ par\u00e7ac\u0131\u011f\u0131n\u0131 BELLE grubu da g\u00f6rd\u00fc\u011f\u00fcn\u00fc a\u00e7\u0131klam\u0131\u015ft\u0131. Ancak bunlar hep d\u00fc\u015f\u00fck istatistiksel verilere sahipti. Bu kez LHCb, \u00f6nceki seferlere g\u00f6re 10 kat daha fazla kez bu par\u00e7ac\u0131\u011fa dair veri oldu\u011funu s\u00f6yledi. 4000 kez par\u00e7ac\u0131k g\u00f6zlemlenmi\u015f. Sahip olduklar\u0131 veri o kadar fazlaki, par\u00e7ac\u0131\u011f\u0131n kuantum numaralar\u0131n\u0131 tart\u0131\u015fmaya neredeyse yer b\u0131rakmayacak \u015fekilde bulmu\u015flar. Bir par\u00e7ac\u0131\u011f\u0131n, kesin kuantum numaralar\u0131n\u0131 bulmak parmak izini \u00e7\u0131karmak gibi bir \u015fey. Fizik\u00e7ilerin tam olarak nas\u0131l bir par\u00e7ac\u0131k oldu\u011funu anlamalar\u0131 i\u00e7in yeterli bilgiyi i\u00e7eriyor yani.<\/p>\n
Sonu\u00e7 olarak Z(4430)- par\u00e7ac\u0131\u011f\u0131n\u0131n t\u0131ls\u0131m, anti-t\u0131ls\u0131m ve a\u015fa\u011f\u0131, anti-yukar\u0131 kuarklardan olu\u015ftu\u011funu s\u00f6yl\u00fcyorlar. Yapt\u0131klar\u0131 \u00f6l\u00e7\u00fcmler di\u011fer bir\u00e7ok olas\u0131l\u0131\u011f\u0131 elemi\u015f. \u00d6l\u00e7\u00fcmde 25200 B mezonunun \u03c8\u2019 \u03c0-a bozunmas\u0131 g\u00f6zlemlenerek deneysel veri seti olu\u015fturulmu\u015f. Z(4430)- par\u00e7ac\u0131\u011f\u0131n\u0131n varl\u0131\u011f\u0131n\u0131 13,9\u03c3 (sigma) hassasiyeti ile \u00f6l\u00e7m\u00fc\u015fler. Bu da demek oluyor ki, sinyaller istatistiksel dalgalanmalardan 13,9 kat g\u00fc\u00e7l\u00fc.<\/p>\n
Par\u00e7ac\u0131\u011f\u0131n bulundu\u011fu kesinle\u015fti\u011fine g\u00f6re, s\u0131rada yap\u0131lmas\u0131 gereken bunun ger\u00e7ekten bir 4\u2019l\u00fc kuark sistemi olup olmad\u0131\u011f\u0131n\u0131 bulmak. 4\u2019l\u00fc sistem olmas\u0131 iki \u015fekilde m\u00fcmk\u00fcn. Bunlardan biri iki tane ikili kuark yap\u0131s\u0131n\u0131n (mezonlar) ba\u011f olu\u015fturmas\u0131 (hidrojen atomu gibi d\u00fc\u015f\u00fcn\u00fclebilir); di\u011feri 4 kuark\u0131n birbiri aras\u0131nda ba\u011f kurmas\u0131. \u0130lk se\u00e7enek pek olas\u0131 g\u00f6z\u00fckm\u00fcyor, \u00e7\u00fcnk\u00fc bu k\u00fctleyi sa\u011flayacak ikili mezon sistemi yok. Ancak 4 kuark\u0131n direkt ba\u011f olu\u015fturdu\u011fu modellere k\u0131yasla bu par\u00e7ac\u0131k 10 kat h\u0131zl\u0131 bozunuyor. Bu da 4\u2019l\u00fc kuark modellerine par\u00e7ac\u0131\u011f\u0131n uymad\u0131\u011f\u0131n\u0131 g\u00f6steriyor.<\/p>\n
Par\u00e7ac\u0131\u011f\u0131n bozunmas\u0131 ve \u00f6zellikleri hakk\u0131nda daha fazla veri topland\u0131k\u00e7a, durum daha da netle\u015fecektir. O zamana kadar 4\u2019l\u00fc kuark yap\u0131lar\u0131n\u0131n varl\u0131\u011f\u0131 sorusu a\u00e7\u0131k bir soru olarak kalacak. T\u0131pk\u0131 5\u2019li kuark yap\u0131lar\u0131 hakk\u0131nda birka\u00e7 kez konu\u015fulmas\u0131na ra\u011fmen, bir s\u00fcredir s\u00f6z edilmemesi, ama buna ra\u011fmen teorik olarak var olmamalar\u0131na bir sebep bulunamamas\u0131 gibi.<\/p>\n
Kaynaklar<\/strong><\/p>\n 1) http:\/\/www.newscientist.com\/article\/dn25402-lhc-spots-particle-that-may-be-new-form-of-matter.html#.U1LSJB9FNj2<\/p>\n 2) http:\/\/arxiv.org\/abs\/1404.1903<\/p>\n <\/p>\n","protected":false},"excerpt":{"rendered":" \u00dcnl\u00fc Higgs par\u00e7ac\u0131\u011f\u0131n\u0131 bulan CERN deneyinde, Higgs par\u00e7ac\u0131\u011f\u0131n\u0131 bulmaktan farkl\u0131 bir i\u015f yapan LHCb grubu, bir ba\u015fka \u00f6nemli bulu\u015fa imza atm\u0131\u015f olabilir. Grup 7 Nisan 2014 tarihinde, arXiv (Cornell \u00dcniversitesi\u2019nin a\u00e7\u0131k makale sistemi) sitesinde egzotik bir par\u00e7ac\u0131\u011f\u0131 bulduklar\u0131n\u0131 a\u00e7\u0131klad\u0131. LHCb grubu, CERN\u2019deki b\u00fcy\u00fck hadron \u00e7arp\u0131\u015ft\u0131r\u0131c\u0131s\u0131 \u00fczerinde kurulmu\u015f olan 4 detekt\u00f6rden birini kullan\u0131yor. Higgs bozonunu bulduklar\u0131n\u0131 […]<\/p>\n","protected":false},"author":620,"featured_media":25491,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[160,30,19,38,26],"tags":[265,1120,2535,1846],"class_list":["post-25488","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-123-sayi","category-astronomi","category-bilim-gundemi","category-dergi-sayilari","category-fizik","tag-cern","tag-hadron","tag-hadron-carpistiricisi","tag-kuark"],"acf":[],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/bilimvegelecek.com.tr\/index.php\/wp-json\/wp\/v2\/posts\/25488","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/bilimvegelecek.com.tr\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/bilimvegelecek.com.tr\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/bilimvegelecek.com.tr\/index.php\/wp-json\/wp\/v2\/users\/620"}],"replies":[{"embeddable":true,"href":"https:\/\/bilimvegelecek.com.tr\/index.php\/wp-json\/wp\/v2\/comments?post=25488"}],"version-history":[{"count":0,"href":"https:\/\/bilimvegelecek.com.tr\/index.php\/wp-json\/wp\/v2\/posts\/25488\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/bilimvegelecek.com.tr\/index.php\/wp-json\/wp\/v2\/media\/25491"}],"wp:attachment":[{"href":"https:\/\/bilimvegelecek.com.tr\/index.php\/wp-json\/wp\/v2\/media?parent=25488"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/bilimvegelecek.com.tr\/index.php\/wp-json\/wp\/v2\/categories?post=25488"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/bilimvegelecek.com.tr\/index.php\/wp-json\/wp\/v2\/tags?post=25488"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}