If the star is sufficiently massive, this will cause the near-instantaneous onset of oxygen fusion, releasing a massive burst of energy. That energy is thought to be enough to completely destroy the star without leaving a remnant black hole behind. Alternatively, smaller bursts of oxygen fusion may blast away the star\u2019s outer layers, leaving a much smaller star behind that will ultimately create a far less massive black hole.<\/p>\n
While that\u2019s pretty well established through modeling, it\u2019s a very difficult process to confirm. There have been a number<\/a> of proposed examples<\/a> of potential pair-instability<\/a> events, and we don\u2019t have a clear picture of what observations would distinguish them from more run-of-the-mill stellar explosions. And while we\u2019ve been able to estimate the mass of the black holes we\u2019ve observed merging, that hasn\u2019t been as helpful as we would like.<\/p>\n The problem is that several of the mergers we\u2019ve seen involve black holes that seem to have merged previously. So they\u2019re big enough to be above the cutoff where pair-instability should have blocked the formation of a black hole, but they might have gotten that hefty by swallowing another black hole.<\/p>\n Numbers to the rescue<\/p>\n The international team behind the new work considered what kinds of collisions we might see. One is two first-generation (G1) black holes merging, in which case both should be below the mass at which pair-instability destroys everything. Then there\u2019s a G1 colliding with a second-generation (G2) that\u2019s the product of a previous merger, with the G2 potentially being above the mass cutoff. Finally, there\u2019s a G2-G2 merger, where both are above the cutoff.<\/p>\n Any black hole mergers are likely to take place within a structure filled with lots of high-mass stars, such as a globular cluster. But the merger itself tends to impart a lot of energy to the resulting black hole, which could potentially kick it out of the cluster. As a result, G2-G2 mergers would likely be far more rare than G1-G2 mergers; the team estimates that only about 1 percent of all mergers would be G2-G2.<\/p>\n","protected":false},"excerpt":{"rendered":"If the star is sufficiently massive, this will cause the near-instantaneous onset of oxygen fusion, releasing a massive…\n","protected":false},"author":2,"featured_media":507726,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[23],"tags":[90,416,56,54,55],"class_list":{"0":"post-507725","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-space","8":"tag-science","9":"tag-space","10":"tag-uk","11":"tag-united-kingdom","12":"tag-unitedkingdom"},"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/posts\/507725","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/comments?post=507725"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/posts\/507725\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/media\/507726"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/media?parent=507725"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/categories?post=507725"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/tags?post=507725"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}