{"id":44853,"date":"2026-05-07T10:57:20","date_gmt":"2026-05-07T08:57:20","guid":{"rendered":"https:\/\/www.ieec.cat\/?p=44853"},"modified":"2026-05-07T10:57:28","modified_gmt":"2026-05-07T08:57:28","slug":"biggest-black-holes-are-born-in-busy-star-clusters-in-violent-merging-events","status":"publish","type":"post","link":"https:\/\/www.ieec.cat\/en\/biggest-black-holes-are-born-in-busy-star-clusters-in-violent-merging-events\/","title":{"rendered":"Biggest black holes are born in busy star clusters in violent merging events"},"content":{"rendered":"<p>[et_pb_section fb_built=&#8221;1&#8243; admin_label=&#8221;Section&#8221; _builder_version=&#8221;4.16&#8243; _module_preset=&#8221;default&#8221; background_image=&#8221;https:\/\/www.ieec.cat\/wp-content\/uploads\/2022\/02\/slider-comunicacio.jpg&#8221; max_height=&#8221;130px&#8221; custom_padding=&#8221;0px||0px||false|false&#8221; da_disable_devices=&#8221;off|off|off&#8221; global_colors_info=&#8221;{}&#8221; da_is_popup=&#8221;off&#8221; da_exit_intent=&#8221;off&#8221; da_has_close=&#8221;on&#8221; da_alt_close=&#8221;off&#8221; da_dark_close=&#8221;off&#8221; da_not_modal=&#8221;on&#8221; da_is_singular=&#8221;off&#8221; da_with_loader=&#8221;off&#8221; da_has_shadow=&#8221;on&#8221;][\/et_pb_section][et_pb_section fb_built=&#8221;1&#8243; admin_label=&#8221;Section&#8221; _builder_version=&#8221;4.16&#8243; _module_preset=&#8221;default&#8221; custom_padding=&#8221;24px||11px|||&#8221; da_disable_devices=&#8221;off|off|off&#8221; global_colors_info=&#8221;{}&#8221; da_is_popup=&#8221;off&#8221; da_exit_intent=&#8221;off&#8221; da_has_close=&#8221;on&#8221; da_alt_close=&#8221;off&#8221; da_dark_close=&#8221;off&#8221; da_not_modal=&#8221;on&#8221; da_is_singular=&#8221;off&#8221; da_with_loader=&#8221;off&#8221; da_has_shadow=&#8221;on&#8221;][et_pb_row _builder_version=&#8221;4.16&#8243; _module_preset=&#8221;default&#8221; custom_padding=&#8221;||||false|false&#8221; global_colors_info=&#8221;{}&#8221;][et_pb_column type=&#8221;4_4&#8243; _builder_version=&#8221;4.16&#8243; _module_preset=&#8221;default&#8221; global_colors_info=&#8221;{}&#8221;][et_pb_text admin_label=&#8221;Unitats de recerca&#8221; module_class=&#8221;ieec-orgs&#8221; _builder_version=&#8221;4.27.4&#8243; _dynamic_attributes=&#8221;content&#8221; _module_preset=&#8221;default&#8221; text_font=&#8221;|700||on|||||&#8221; text_font_size=&#8221;16px&#8221; header_font=&#8221;|700|||||||&#8221; custom_margin=&#8221;||10px||false|false&#8221; header_font_size_tablet=&#8221;28px&#8221; header_font_size_phone=&#8221;26px&#8221; header_font_size_last_edited=&#8221;on|phone&#8221; global_colors_info=&#8221;{}&#8221;]@ET-DC@eyJkeW5hbWljIjp0cnVlLCJjb250ZW50IjoiY3VzdG9tX21ldGFfb3JnYW5pemFjaW9uZXMiLCJzZXR0aW5ncyI6eyJiZWZvcmUiOiIiLCJhZnRlciI6IiIsImVuYWJsZV9odG1sIjoib2ZmIn19@[\/et_pb_text][et_pb_post_title author=&#8221;off&#8221; categories=&#8221;off&#8221; comments=&#8221;off&#8221; featured_image=&#8221;off&#8221; admin_label=&#8221;T\u00edtol i data&#8221; module_class=&#8221;ieec-title&#8221; _builder_version=&#8221;4.27.6&#8243; _module_preset=&#8221;default&#8221; title_font=&#8221;Cairo|300|||||||&#8221; title_font_size=&#8221;40px&#8221; meta_font=&#8221;||on||||||&#8221; meta_font_size=&#8221;16px&#8221; title_font_size_tablet=&#8221;35px&#8221; title_font_size_phone=&#8221;30px&#8221; title_font_size_last_edited=&#8221;on|desktop&#8221; global_colors_info=&#8221;{}&#8221;][\/et_pb_post_title][et_pb_text admin_label=&#8221;Subt\u00edtols&#8221; module_class=&#8221;ieec-summary&#8221; _builder_version=&#8221;4.27.6&#8243; _module_preset=&#8221;default&#8221; text_font=&#8221;Source Sans Pro||on||||||&#8221; text_font_size=&#8221;24px&#8221; text_line_height=&#8221;1.1em&#8221; hover_enabled=&#8221;0&#8243; text_font_size_tablet=&#8221;22px&#8221; text_font_size_phone=&#8221;20px&#8221; text_font_size_last_edited=&#8221;on|phone&#8221; global_colors_info=&#8221;{}&#8221; sticky_enabled=&#8221;0&#8243;]<\/p>\n<ul>\n<li>The team has identified two distinct black hole populations in version 4.0 of the Gravitational-Wave Transient Catalog<\/li>\n<li>The study also provides the strongest evidence yet for a \u201cmass gap\u201d, the range of masses where stars are not expected to leave behind black holes at all<\/li>\n<li>IEEC researchers at the Institute of Cosmos Sciences (ICCUB) have participated in this study, published in Nature Astronomy<\/li>\n<\/ul>\n<p>[\/et_pb_text][\/et_pb_column][\/et_pb_row][et_pb_row column_structure=&#8221;1_2,1_2&#8243; _builder_version=&#8221;4.16&#8243; _module_preset=&#8221;default&#8221; global_colors_info=&#8221;{}&#8221;][et_pb_column type=&#8221;1_2&#8243; _builder_version=&#8221;4.16&#8243; _module_preset=&#8221;default&#8221; global_colors_info=&#8221;{}&#8221;][et_pb_post_title title=&#8221;off&#8221; meta=&#8221;off&#8221; module_class=&#8221;ieec-img-container&#8221; _builder_version=&#8221;4.27.2&#8243; _module_preset=&#8221;default&#8221; custom_margin=&#8221;||0px||false|false&#8221; border_width_top=&#8221;10px&#8221; border_color_top=&#8221;#406fda&#8221; global_colors_info=&#8221;{}&#8221;][\/et_pb_post_title][et_pb_text module_class=&#8221;ieec-img-footer&#8221; _builder_version=&#8221;4.27.6&#8243; _module_preset=&#8221;default&#8221; text_font=&#8221;||||||||&#8221; text_font_size=&#8221;15px&#8221; text_line_height=&#8221;1.1em&#8221; background_color=&#8221;rgba(64,111,218,0.15)&#8221; custom_margin=&#8221;0px||||false|false&#8221; custom_padding=&#8221;30px|20px|30px|20px|true|true&#8221; hover_enabled=&#8221;0&#8243; global_colors_info=&#8221;{}&#8221; sticky_enabled=&#8221;0&#8243;]<\/p>\n<p>About 28,000 light-years away, the globular cluster M80 is home to hundreds of thousands of stars bound together by gravity. Crowded environments like this can help drive the growth of black holes through consecutive mergers. <strong>NASA, ESA, STScI and A. Sarajedini (University of Florida)<\/strong><\/p>\n<p>[\/et_pb_text][\/et_pb_column][et_pb_column type=&#8221;1_2&#8243; _builder_version=&#8221;4.16&#8243; _module_preset=&#8221;default&#8221; global_colors_info=&#8221;{}&#8221;][et_pb_text _builder_version=&#8221;4.27.6&#8243; _module_preset=&#8221;default&#8221; link_font=&#8221;|700|||on||||&#8221; hover_enabled=&#8221;0&#8243; global_colors_info=&#8221;{}&#8221; sticky_enabled=&#8221;0&#8243;]<\/p>\n<p><span style=\"font-weight: 400;\">The most massive black holes in the Universe detected by the ripples they make in spacetime were not born directly from collapsing\u00a0stars, according to a new study. These cosmic giants instead build up through <\/span><b>a series of repeated and extremely violent collision events<\/b><span style=\"font-weight: 400;\"> in very densely populated star clusters, an international team of researchers argue in an article published today in the journal Nature Astronomy.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Their study, led by <\/span><a href=\"https:\/\/www.cardiff.ac.uk\/\" target=\"_blank\" rel=\"noopener\"><span style=\"font-weight: 400;\">Cardiff University<\/span><\/a><span style=\"font-weight: 400;\">, analysed version 4.0 of LIGO\u2013Virgo\u2013KAGRA\u2019s Gravitational-Wave Transient\u00a0Catalog\u00a0(GWTC-4), containing 153 sufficiently confident black hole merger detections. The <\/span><a href=\"https:\/\/www.ieec.cat\/en\/\"><span style=\"font-weight: 400;\">Institute of Space Studies of Catalonia<\/span><\/a><span style=\"font-weight: 400;\"> (IEEC \u2014 Institut d\u2019Estudis Espacials de Catalunya) participated in this study through researchers at the <\/span><a href=\"https:\/\/icc.ub.edu\/\" target=\"_blank\" rel=\"noopener\"><span style=\"font-weight: 400;\">Institute of Cosmos Sciences of the University of Barcelona<\/span><\/a><span style=\"font-weight: 400;\"> (ICCUB).<\/span><\/p>\n<p><span style=\"font-weight: 400;\">The team wanted to test the idea that the heaviest black holes in GWTC-4 are second-generation objects, formed when earlier black holes merged and then merged again in the dense cores of star clusters, where <\/span><b>stars can be packed up to a million times more tightly than in the Sun\u2019s neighbourhood<\/b><span style=\"font-weight: 400;\">. Their findings probe the origins of the heaviest black holes detected by their gravitational waves, revealing two distinct populations.<\/span><\/p>\n<p>[\/et_pb_text][\/et_pb_column][\/et_pb_row][et_pb_row _builder_version=&#8221;4.16&#8243; _module_preset=&#8221;default&#8221; global_colors_info=&#8221;{}&#8221;][et_pb_column type=&#8221;4_4&#8243; _builder_version=&#8221;4.16&#8243; _module_preset=&#8221;default&#8221; global_colors_info=&#8221;{}&#8221;][et_pb_text _builder_version=&#8221;4.27.6&#8243; _module_preset=&#8221;default&#8221; link_font=&#8221;|700|||on||||&#8221; hover_enabled=&#8221;0&#8243; locked=&#8221;off&#8221; global_colors_info=&#8221;{}&#8221; sticky_enabled=&#8221;0&#8243;]<\/p>\n<p><span style=\"font-weight: 400;\">\u201cGravitational-wave astronomy is now doing more than counting black hole mergers,\u201d explains lead author Fabio Antonini from Cardiff University\u2019s School of Physics and Astronomy. \u201cIt is starting to reveal how black holes grow, where they grow, and what that tells us about the lives and deaths of massive stars.\u201d<\/span><\/p>\n<p><span style=\"font-weight: 400;\">\u201cThe ability to directly point to star clusters as the origin for these mergers opens up the exciting possibility to use gravitational waves as a completely new tool to learn about the formation and early evolution of dense star clusters that form in the early Universe,\u201d says co-author Mark Gieles, ICREA research professor at the IEEC and ICCUB.<\/span><\/p>\n<p>[\/et_pb_text][\/et_pb_column][\/et_pb_row][et_pb_row _builder_version=&#8221;4.16&#8243; _module_preset=&#8221;default&#8221; global_colors_info=&#8221;{}&#8221;][et_pb_column type=&#8221;4_4&#8243; _builder_version=&#8221;4.16&#8243; _module_preset=&#8221;default&#8221; global_colors_info=&#8221;{}&#8221;][et_pb_text module_class=&#8221;section-title&#8221; _builder_version=&#8221;4.27.6&#8243; _module_preset=&#8221;default&#8221; header_2_font=&#8221;|700|||||||&#8221; header_2_font_size=&#8221;25px&#8221; hover_enabled=&#8221;0&#8243; header_2_font_size_tablet=&#8221;23px&#8221; header_2_font_size_phone=&#8221;23px&#8221; header_2_font_size_last_edited=&#8221;on|phone&#8221; global_colors_info=&#8221;{}&#8221; sticky_enabled=&#8221;0&#8243;]<\/p>\n<h2>Two black-hole populations<\/h2>\n<p>[\/et_pb_text][et_pb_text _builder_version=&#8221;4.27.6&#8243; _module_preset=&#8221;default&#8221; link_font=&#8221;|700|||on||||&#8221; hover_enabled=&#8221;0&#8243; locked=&#8221;off&#8221; global_colors_info=&#8221;{}&#8221; sticky_enabled=&#8221;0&#8243;]<\/p>\n<p><span style=\"font-weight: 400;\">In the gravitational-wave data, the team identified, on the one hand, a lower-mass population consistent with ordinary stellar collapse and, on the other hand, a higher-mass population whose spins appear exactly like those expected if <\/span><b>those black holes were formed by repeatedly merging with other black holes <\/b><span style=\"font-weight: 400;\">inside crowded groups of stars, rather than being born directly from single stars.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">\u201cWhat surprised us most was how clearly the high-mass black holes stand out as a separate population,\u201d recalls co-author Isobel Romero-Shaw, Ernest Rutherford Fellow at Cardiff University.\u00a0<\/span><\/p>\n<p><span style=\"font-weight: 400;\">\u201cUnlike the lower-mass systems we analysed, which were generally slowly-spinning, the higher-mass systems are consistent with having more rapid spins, oriented in seemingly random directions,\u201d she adds. \u201cThis is the exact signature you would expect if black holes were repeatedly merging in dense star clusters. That makes the cluster origin much more compelling than it was with earlier catalogues.\u201d<\/span><\/p>\n<p>[\/et_pb_text][\/et_pb_column][\/et_pb_row][et_pb_row _builder_version=&#8221;4.16&#8243; _module_preset=&#8221;default&#8221; global_colors_info=&#8221;{}&#8221;][et_pb_column type=&#8221;4_4&#8243; _builder_version=&#8221;4.16&#8243; _module_preset=&#8221;default&#8221; global_colors_info=&#8221;{}&#8221;][et_pb_text module_class=&#8221;section-title&#8221; _builder_version=&#8221;4.27.6&#8243; _module_preset=&#8221;default&#8221; header_2_font=&#8221;|700|||||||&#8221; header_2_font_size=&#8221;25px&#8221; hover_enabled=&#8221;0&#8243; header_2_font_size_tablet=&#8221;23px&#8221; header_2_font_size_phone=&#8221;23px&#8221; header_2_font_size_last_edited=&#8221;on|phone&#8221; global_colors_info=&#8221;{}&#8221; sticky_enabled=&#8221;0&#8243;]<\/p>\n<h2>A \u201cmass gap\u201d for black holes<\/h2>\n<p>[\/et_pb_text][et_pb_text _builder_version=&#8221;4.27.6&#8243; _module_preset=&#8221;default&#8221; link_font=&#8221;|700|||on||||&#8221; hover_enabled=&#8221;0&#8243; locked=&#8221;off&#8221; global_colors_info=&#8221;{}&#8221; sticky_enabled=&#8221;0&#8243;]<\/p>\n<p><span style=\"font-weight: 400;\">The study also provides<\/span> <span style=\"font-weight: 400;\">the strongest evidence yet for a \u201cmass gap\u201d, where extremely massive stars explode catastrophically rather than collapsing into black holes. The long-predicted theory describes<\/span><b> a forbidden mass range for black holes made directly from stars<\/b><span style=\"font-weight: 400;\">, where very massive stars are expected to be disrupted before they can form black holes.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">The team pinpoints this range in a population of stellar-origin black holes<\/span><b> 45 times the mass of the Sun and above<\/b><span style=\"font-weight: 400;\">. Antonini said: \u201cIn our study we find evidence for the long-predicted pair-instability mass gap. Gravitational-wave detectors have successfully found black holes that appear to sit in or near that gap, which we identify at around 45 solar masses.\u00a0<\/span><\/p>\n<p><span style=\"font-weight: 400;\">\u201cSo, the key question now is: are these black holes telling us that our models of stellar evolution are wrong, or are they being made in another way?,\u201d Antonini wonders. \u201cThe biggest black holes in the current sample seem to be telling us about cluster dynamics, not just stellar evolution.\u201d<\/span><\/p>\n<p><span style=\"font-weight: 400;\">He continues: \u201cAbove about 45 solar masses the spin distribution changes in a way that is hard to explain with normal stellar binaries\u00a0alone but\u00a0is naturally explained if these black holes have already been through earlier mergers in dense clusters.\u201d<\/span><\/p>\n<p><span style=\"font-weight: 400;\">The team also used this transition to shed light on an important nuclear reaction involved in helium burning inside massive stars. \u201cIn the future, gravitational-wave data may help scientists study nuclear physics, because the mass limit set by pair instability depends on the nuclear reactions taking place in the cores of massive stars,\u201d added<\/span> <span style=\"font-weight: 400;\">co-author Fani Dosopoulou, a research associate at Cardiff University.<\/span><\/p>\n<p>[\/et_pb_text][\/et_pb_column][\/et_pb_row][et_pb_row _builder_version=&#8221;4.16&#8243; _module_preset=&#8221;default&#8221; custom_margin=&#8221;30px||||false|false&#8221; locked=&#8221;off&#8221; global_colors_info=&#8221;{}&#8221;][et_pb_column type=&#8221;4_4&#8243; _builder_version=&#8221;4.16&#8243; _module_preset=&#8221;default&#8221; global_colors_info=&#8221;{}&#8221;][et_pb_divider color=&#8221;#406fda&#8221; _builder_version=&#8221;4.16&#8243; _module_preset=&#8221;default&#8221; custom_margin=&#8221;||10px||false|false&#8221; global_colors_info=&#8221;{}&#8221;][\/et_pb_divider][et_pb_text admin_label=&#8221;M\u00e9s informaci\u00f3&#8221; module_class=&#8221;ieec-sub-title&#8221; _builder_version=&#8221;4.27.6&#8243; _module_preset=&#8221;default&#8221; text_font=&#8221;Cairo|700|||||||&#8221; text_text_color=&#8221;#406fda&#8221; text_font_size=&#8221;20px&#8221; custom_margin=&#8221;||10px||false|false&#8221; hover_enabled=&#8221;0&#8243; global_colors_info=&#8221;{}&#8221; sticky_enabled=&#8221;0&#8243;]<\/p>\n<p>More information<\/p>\n<p>[\/et_pb_text][et_pb_text module_class=&#8221;ieec-sub-text&#8221; _builder_version=&#8221;4.27.6&#8243; _module_preset=&#8221;default&#8221; text_font_size=&#8221;16px&#8221; text_line_height=&#8221;1.1em&#8221; link_font=&#8221;|700|||on||||&#8221; custom_margin=&#8221;20px||||false|false&#8221; hover_enabled=&#8221;0&#8243; global_colors_info=&#8221;{}&#8221; sticky_enabled=&#8221;0&#8243;]<\/p>\n<p><span style=\"font-weight: 400;\">This research is presented in a paper entitled \u201c<\/span><a href=\"https:\/\/doi.org\/10.1038\/s41550-026-02847-0\" target=\"_blank\" rel=\"noopener\"><span style=\"font-weight: 400;\">Gravitational waves reveal the pair-instability mass gap and constrain nuclear burning in massive stars<\/span><\/a><span style=\"font-weight: 400;\">\u201d, by <\/span><span style=\"font-weight: 400;\">Antonini, F.<\/span> <i><span style=\"font-weight: 400;\">et al.<\/span><\/i><span style=\"font-weight: 400;\">, to appear in the journal Nature Astronomy on 7 May 2026.<\/span><\/p>\n<p>[\/et_pb_text][\/et_pb_column][\/et_pb_row][et_pb_row _builder_version=&#8221;4.16&#8243; _module_preset=&#8221;default&#8221; custom_margin=&#8221;||||false|false&#8221; locked=&#8221;off&#8221; global_colors_info=&#8221;{}&#8221;][et_pb_column type=&#8221;4_4&#8243; _builder_version=&#8221;4.16&#8243; _module_preset=&#8221;default&#8221; global_colors_info=&#8221;{}&#8221;][et_pb_divider color=&#8221;#406fda&#8221; _builder_version=&#8221;4.16&#8243; _module_preset=&#8221;default&#8221; custom_margin=&#8221;||10px||false|false&#8221; global_colors_info=&#8221;{}&#8221;][\/et_pb_divider][et_pb_text admin_label=&#8221;Enlla\u00e7os&#8221; module_class=&#8221;ieec-sub-title&#8221; _builder_version=&#8221;4.27.6&#8243; _module_preset=&#8221;default&#8221; text_font=&#8221;Cairo|700|||||||&#8221; text_text_color=&#8221;#406fda&#8221; text_font_size=&#8221;20px&#8221; custom_margin=&#8221;||10px||false|false&#8221; hover_enabled=&#8221;0&#8243; global_colors_info=&#8221;{}&#8221; sticky_enabled=&#8221;0&#8243;]<\/p>\n<p>Links<\/p>\n<p>[\/et_pb_text][et_pb_text module_class=&#8221;ieec-sub-text&#8221; _builder_version=&#8221;4.27.6&#8243; _module_preset=&#8221;default&#8221; text_font_size=&#8221;16px&#8221; text_line_height=&#8221;1.1em&#8221; link_font=&#8221;|700|||on|||#1a1140|&#8221; link_text_color=&#8221;#1a1140&#8243; link_line_height=&#8221;1.4em&#8221; custom_margin=&#8221;20px||||false|false&#8221; global_colors_info=&#8221;{}&#8221;]<\/p>\n<ul>\n<li><a href=\"http:\/\/www.ieec.cat\/en\/\"><span style=\"font-weight: 400;\">IEEC<\/span><\/a><\/li>\n<li><a href=\"https:\/\/icc.ub.edu\/\" target=\"_blank\" rel=\"noopener\"><span style=\"font-weight: 400;\">ICCUB<\/span><\/a><\/li>\n<\/ul>\n<p>[\/et_pb_text][\/et_pb_column][\/et_pb_row][et_pb_row _builder_version=&#8221;4.16&#8243; _module_preset=&#8221;default&#8221; custom_margin=&#8221;||||false|false&#8221; locked=&#8221;off&#8221; global_colors_info=&#8221;{}&#8221;][et_pb_column type=&#8221;4_4&#8243; _builder_version=&#8221;4.16&#8243; _module_preset=&#8221;default&#8221; global_colors_info=&#8221;{}&#8221;][et_pb_divider color=&#8221;#406fda&#8221; _builder_version=&#8221;4.16&#8243; _module_preset=&#8221;default&#8221; custom_margin=&#8221;||10px||false|false&#8221; global_colors_info=&#8221;{}&#8221;][\/et_pb_divider][et_pb_text admin_label=&#8221;Contactes&#8221; module_class=&#8221;ieec-sub-title&#8221; _builder_version=&#8221;4.27.6&#8243; _module_preset=&#8221;default&#8221; text_font=&#8221;Cairo|700|||||||&#8221; text_text_color=&#8221;#406fda&#8221; text_font_size=&#8221;20px&#8221; custom_margin=&#8221;||10px||false|false&#8221; hover_enabled=&#8221;0&#8243; global_colors_info=&#8221;{}&#8221; sticky_enabled=&#8221;0&#8243;]<\/p>\n<p>Contacts<\/p>\n<p>[\/et_pb_text][\/et_pb_column][\/et_pb_row][et_pb_row column_structure=&#8221;2_5,3_5&#8243; admin_label=&#8221;Row&#8221; _builder_version=&#8221;4.16&#8243; _module_preset=&#8221;default&#8221; custom_margin=&#8221;0px||||false|false&#8221; custom_padding=&#8221;0px||||false|false&#8221; global_colors_info=&#8221;{}&#8221; theme_builder_area=&#8221;post_content&#8221;][et_pb_column type=&#8221;2_5&#8243; _builder_version=&#8221;4.16&#8243; _module_preset=&#8221;default&#8221; custom_padding=&#8221;|||20px|false|false&#8221; border_width_left=&#8221;1px&#8221; border_color_left=&#8221;#406fda&#8221; global_colors_info=&#8221;{}&#8221; theme_builder_area=&#8221;post_content&#8221;][et_pb_text _builder_version=&#8221;4.16&#8243; _module_preset=&#8221;default&#8221; text_font_size=&#8221;16px&#8221; text_line_height=&#8221;1.1em&#8221; link_font=&#8221;|700|||on|||#1a1140|&#8221; link_text_color=&#8221;#1a1140&#8243; link_line_height=&#8221;1.4em&#8221; header_4_font=&#8221;|700|||||||&#8221; header_4_text_color=&#8221;#1a1140&#8243; custom_margin=&#8221;||||false|false&#8221; locked=&#8221;off&#8221; global_colors_info=&#8221;{}&#8221; theme_builder_area=&#8221;post_content&#8221;]<\/p>\n<h4>IEEC Communication Office<\/h4>\n<p>Castelldefels, Barcelona<br \/>E-mail: <a href=\"mailto:comunicacio@ieec.cat\">comunicacio@ieec.cat<\/a><\/p>\n<p>[\/et_pb_text][\/et_pb_column][et_pb_column type=&#8221;3_5&#8243; _builder_version=&#8221;4.16&#8243; _module_preset=&#8221;default&#8221; custom_padding=&#8221;|||20px|false|false&#8221; border_width_left=&#8221;1px&#8221; border_color_left=&#8221;#406fda&#8221; global_colors_info=&#8221;{}&#8221; theme_builder_area=&#8221;post_content&#8221;][et_pb_text _builder_version=&#8221;4.27.6&#8243; _module_preset=&#8221;default&#8221; text_font_size=&#8221;16px&#8221; text_line_height=&#8221;1em&#8221; link_font=&#8221;|700|||on||||&#8221; link_text_color=&#8221;#1a1140&#8243; header_4_font=&#8221;|700|||||||&#8221; header_4_text_color=&#8221;#1a1140&#8243; hover_enabled=&#8221;0&#8243; global_colors_info=&#8221;{}&#8221; theme_builder_area=&#8221;post_content&#8221; sticky_enabled=&#8221;0&#8243;]<\/p>\n<h4>Lead Researcher at the IEEC<\/h4>\n<h4>Mark Gieles<\/h4>\n<p>Institute of Space Studies of Catalonia (IEEC)<br \/>Institute of Cosmos Sciences (ICCUB)<br \/>E-mail: <a href=\"mailto:mgieles@ieec.cat,\">mgieles@ieec.cat,<\/a> <a href=\"mailto:mgieles@icc.ub.edu\">mgieles@icc.ub.edu<\/a><\/p>\n<p>[\/et_pb_text][\/et_pb_column][\/et_pb_row][et_pb_row module_id=&#8221;ieec-about&#8221; module_class=&#8221;about-ieec&#8221; _builder_version=&#8221;4.27.4&#8243; _module_preset=&#8221;default&#8221; background_color=&#8221;rgba(64,111,218,0.15)&#8221; global_module=&#8221;17324&#8243; global_colors_info=&#8221;{}&#8221;][et_pb_column type=&#8221;4_4&#8243; _builder_version=&#8221;4.16&#8243; _module_preset=&#8221;default&#8221; custom_padding=&#8221;20px|50px|20px|50px|true|true&#8221; global_colors_info=&#8221;{}&#8221;][et_pb_text admin_label=&#8221;Sobre l&#8217;IEEC&#8221; _builder_version=&#8221;4.16&#8243; _module_preset=&#8221;default&#8221; header_2_font=&#8221;|700|||||||&#8221; header_2_font_size=&#8221;25px&#8221; custom_margin=&#8221;||10px||false|false&#8221; header_2_font_size_tablet=&#8221;23px&#8221; header_2_font_size_phone=&#8221;23px&#8221; header_2_font_size_last_edited=&#8221;on|phone&#8221; locked=&#8221;off&#8221; global_colors_info=&#8221;{}&#8221;]<\/p>\n<h2>About the IEEC<\/h2>\n<p>[\/et_pb_text][et_pb_text admin_label=&#8221;Text&#8221; _builder_version=&#8221;4.16&#8243; _module_preset=&#8221;default&#8221; text_font=&#8221;||on||||||&#8221; link_font=&#8221;|700|||on||||&#8221; locked=&#8221;off&#8221; global_colors_info=&#8221;{}&#8221;]<\/p>\n<p>The Institute of Space Studies of Catalonia (IEEC \u2014 Institut d\u2019Estudis Espacials de Catalunya) promotes and coordinates space research and technology development in Catalonia for the benefit of society. IEEC fosters collaborations both locally and worldwide and is an efficient agent of knowledge, innovation and technology transfer. As a result of more than 25 years of high-quality research, done in collaboration with major international organisations, IEEC ranks among the best international research centres, focusing on areas such as: astrophysics, cosmology, planetary science, and Earth Observation. IEEC\u2019s engineering division develops instrumentation for ground- and space-based projects, and has extensive experience in working with private or public organisations from the aerospace and other innovation sectors.<\/p>\n<p>The IEEC is a non-profit public sector foundation that was established in February 1996. It has a Board of Trustees composed of the Generalitat de Catalunya, Universitat de Barcelona (UB), Universitat Aut\u00f2noma de Barcelona (UAB), Universitat Polit\u00e8cnica de Catalunya \u00b7 BarcelonaTech (UPC), and the Spanish Research Council (CSIC). The IEEC is also a CERCA centre.<\/p>\n<p>[\/et_pb_text][\/et_pb_column][\/et_pb_row][\/et_pb_section]<\/p>\n","protected":false},"excerpt":{"rendered":"<p>The study, published in Nature Astronomy, also provides the strongest evidence yet for a \u201cmass gap\u201d, the range of masses where stars are not expected to leave behind black holes at all.<\/p>\n","protected":false},"author":5,"featured_media":44855,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_et_pb_use_builder":"on","_et_pb_old_content":"","_et_gb_content_width":"2880","footnotes":""},"categories":[74,111,98],"tags":[],"class_list":["post-44853","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-news","category-highlighted-news-small","category-science"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.5 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>Biggest black holes are born in busy star clusters in violent merging events - 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