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Abstract As LIGO-Virgo-KAGRA enters its fourth observing run, a new opportunity to search for electromagnetic counterparts of compact object mergers will also begin. The light curves and spectra from the first “kilonova” associated with a binary neutron star merger (NSM) suggests that these sites are hosts of the rapid neutron capture (“r”) process. However, it is unknown just how robust elemental production can be in mergers. Identifying signposts of the production of particular nuclei is critical for fully understanding merger-driven heavy-element synthesis. In this study, we investigate the properties of very neutron-rich nuclei for which superheavy elements (Z≥ 104) can be produced in NSMs and whether they can similarly imprint a unique signature on kilonova light-curve evolution. A superheavy-element signature in kilonovae represents a route to establishing a lower limit on heavy-element production in NSMs as well as possibly being the first evidence of superheavy-element synthesis in nature. Favorable NSM conditions yield a mass fraction of superheavy elementsXZ≥104≈ 3 × 10−2at 7.5 hr post-merger. With this mass fraction of superheavy elements, we find that the component of kilonova light curves possibly containing superheavy elements may appear similar to those arising from lanthanide-poor ejecta. Therefore, photometric characterizations of superheavy-element rich kilonova may possibly misidentify them as lanthanide-poor events.
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Were the Superheavy Elements made in Space?
A question for decades has been the potential production of heavy or superheavy elements in nature. Once the nuclear weapons tests showed that elements heavier than the Uranium were found in the debris, it was clear that a rapid neutron capture process followed by beta decay was creating heavier elements. The next question was the location of the r-process end? What other heavy elements are made? Did nature make the superheavy elements via the r-process too? The answer is yet to be found. There are many indications that it probably did but the definitive evidence is yet to surface. The laboratory experiments with neutron rich beams and neutron rich targets via cold and hot fusion reactions have created a number of new isotopes in addition to the elements that have completed the periodic table. Furthermore, the new superheavy element factory at the JINR in Dubna has now allowed the identification of over one hundred decay chains of the various isotopes of superheavy elements connecting to the main part of the chart of nuclides via decays. This is where we should look for the definitive evidence for the production of the superheavy elements in nature.
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- PAR ID:
- 10543930
- Editor(s):
- Bijker, R; Marín_Lámbarri, DJ; Yépez_Martínez, TC
- Publisher / Repository:
- EPJ
- Date Published:
- Journal Name:
- EPJ Web of Conferences
- Volume:
- 301
- ISSN:
- 2100-014X
- Page Range / eLocation ID:
- 01001
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1051/epjconf/202430101001
