Tetraneutron: Difference between revisions
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== Marqués' experiment == | == Marqués' experiment == | ||
[[Francisco-Miguel Marques|Francisco-Miguel Marqués]] and co-workers at the [[Grand Accélérateur National d'Ions Lourds|GANIL]] accelerator in [[Caen]] used a [[particle accelerator]] to fire atomic nuclei at carbon targets and observed the "spray" of particles from the resulting collisions.<ref>{{Cite journal |last1=Marqués |first1=F. Miguel |last2=Carbonell |first2=Jaume |date=March 2021 |title=The quest for light multineutron systems |url=https://link.springer.com/10.1140/epja/s10050-021-00417-8 |journal=The European Physical Journal A |language=en |volume=57 |issue=3 |page=105 |doi=10.1140/epja/s10050-021-00417-8 |issn=1434-6001|arxiv=2102.10879 |bibcode=2021EPJA...57..105M |s2cid=231986449 }}</ref> In this case the experiment involved firing [[beryllium-14]], [[boron-15]] and [[lithium-11]] nuclei at a small [[carbon]] target, the most successful being beryllium-14. This isotope of beryllium has a [[nuclear halo]] that consists of four clustered neutrons; this allows it to be easily separated intact in the high-speed collision with the carbon target.<ref name="marques02">{{Cite journal |last1=Marqués |first1=F. M. |last2=Labiche |first2=M. |last3=Orr |first3=N. A. |last4=Angélique |first4=J. C. |last5=Axelsson |first5=L. |last6=Benoit |first6=B. |last7=Bergmann |first7=U. C. |last8=Borge |first8=M. J. G. |last9=Catford |first9=W. N. |last10=Chappell |first10=S. P. G. |last11=Clarke |first11=N. M. |last12=Costa |first12=G. |last13=Curtis |first13=N. |last14= | [[Francisco-Miguel Marques|Francisco-Miguel Marqués]] and co-workers at the [[Grand Accélérateur National d'Ions Lourds|GANIL]] accelerator in [[Caen]] used a [[particle accelerator]] to fire atomic nuclei at carbon targets and observed the "spray" of particles from the resulting collisions.<ref>{{Cite journal |last1=Marqués |first1=F. Miguel |last2=Carbonell |first2=Jaume |date=March 2021 |title=The quest for light multineutron systems |url=https://link.springer.com/10.1140/epja/s10050-021-00417-8 |journal=The European Physical Journal A |language=en |volume=57 |issue=3 |page=105 |doi=10.1140/epja/s10050-021-00417-8 |issn=1434-6001|arxiv=2102.10879 |bibcode=2021EPJA...57..105M |s2cid=231986449 }}</ref> In this case the experiment involved firing [[beryllium-14]], [[boron-15]] and [[lithium-11]] nuclei at a small [[carbon]] target, the most successful being beryllium-14. This isotope of beryllium has a [[nuclear halo]] that consists of four clustered neutrons; this allows it to be easily separated intact in the high-speed collision with the carbon target.<ref name="marques02">{{Cite journal |last1=Marqués |first1=F. M. |last2=Labiche |first2=M. |last3=Orr |first3=N. A. |last4=Angélique |first4=J. C. |last5=Axelsson |first5=L. |last6=Benoit |first6=B. |last7=Bergmann |first7=U. C. |last8=Borge |first8=M. J. G. |last9=Catford |first9=W. N. |last10=Chappell |first10=S. P. G. |last11=Clarke |first11=N. M. |last12=Costa |first12=G. |last13=Curtis |first13=N. |last14=D'Arrigo |first14=A. |last15=de Góes Brennand |first15=E. |date=2002-04-01 |title=Detection of neutron clusters |url=https://link.aps.org/doi/10.1103/PhysRevC.65.044006 |journal=Physical Review C |language=en |volume=65 |issue=4 |article-number=044006 |doi=10.1103/PhysRevC.65.044006 |issn=0556-2813|arxiv=nucl-ex/0111001 |bibcode=2002PhRvC..65d4006M |hdl=10261/7347 |s2cid=37431352 }}</ref> Current nuclear models suggest that four separate neutrons should result when [[beryllium-10]] is produced, but the single signal detected in the production of beryllium-10 suggested a multineutron cluster in the breakup products; most likely a beryllium-10 nucleus and four neutrons fused together into a tetraneutron. | ||
A later analysis of the method used in the Marqués' experiment suggested that the detection mechanism was unlikely<ref name="sherrill04">{{cite journal | A later analysis of the method used in the Marqués' experiment suggested that the detection mechanism was unlikely<ref name="sherrill04">{{cite journal | ||
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| title = Proton-tetraneutron elastic scattering | | title = Proton-tetraneutron elastic scattering | ||
| journal = [[Physical Review C]] | | journal = [[Physical Review C]] | ||
| volume = 69 | issue = 2 | | | volume = 69 | issue = 2 | article-number = 027601 | ||
| doi = 10.1103/PhysRevC.69.027601 | | doi = 10.1103/PhysRevC.69.027601 | ||
| arxiv = nucl-th/0312110 |bibcode = 2004PhRvC..69b7601S | s2cid = 26590179 | | arxiv = nucl-th/0312110 |bibcode = 2004PhRvC..69b7601S | s2cid = 26590179 | ||
| Line 65: | Line 65: | ||
| title = Three-neutron resonance trajectories for realistic interaction models | | title = Three-neutron resonance trajectories for realistic interaction models | ||
| journal = [[Physical Review C]] | | journal = [[Physical Review C]] | ||
| volume = 71 | | | volume = 71 | article-number = 044004 | ||
| doi = 10.1103/PhysRevC.71.044004 | | doi = 10.1103/PhysRevC.71.044004 | ||
| arxiv= nucl-th/0502037v2 | | arxiv= nucl-th/0502037v2 | ||
| Line 75: | Line 75: | ||
| title = Resonance states of <sup>5</sup>H and <sup>5</sup>Be in a microscopic three-cluster model | | title = Resonance states of <sup>5</sup>H and <sup>5</sup>Be in a microscopic three-cluster model | ||
| journal = [[Physical Review C]] | | journal = [[Physical Review C]] | ||
| volume = 68 | issue = 3 | | | volume = 68 | issue = 3 | article-number = 034303 | ||
| doi = 10.1103/PhysRevC.68.034303 | | doi = 10.1103/PhysRevC.68.034303 | ||
|bibcode = 2003PhRvC..68c4303A | |bibcode = 2003PhRvC..68c4303A | ||
| Line 85: | Line 85: | ||
| title = Indications for the nonexistence of three-neutron resonances near the physical region | | title = Indications for the nonexistence of three-neutron resonances near the physical region | ||
| journal = [[Physical Review C]] | | journal = [[Physical Review C]] | ||
| volume = 66 | issue = 3 | | | volume = 66 | issue = 3 | article-number = 054001 | ||
| doi = 10.1103/PhysRevC.66.054001 | | doi = 10.1103/PhysRevC.66.054001 | ||
| arxiv=nucl-th/0208007 | | arxiv=nucl-th/0208007 | ||
| Line 96: | Line 96: | ||
| title = Can Modern Nuclear Hamiltonians Tolerate a Bound Tetraneutron? | | title = Can Modern Nuclear Hamiltonians Tolerate a Bound Tetraneutron? | ||
| journal = [[Physical Review Letters]] | | journal = [[Physical Review Letters]] | ||
| volume = 90 | issue = 25 | | | volume = 90 | issue = 25 | article-number = 252501 | ||
| doi = 10.1103/PhysRevLett.90.252501 | | doi = 10.1103/PhysRevLett.90.252501 | ||
| arxiv=nucl-th/0302048 | | arxiv=nucl-th/0302048 | ||
| Line 110: | Line 110: | ||
| last3 = Albertus | first3 = C. | | last3 = Albertus | first3 = C. | ||
| journal = European Physical Journal A | | journal = European Physical Journal A | ||
| volume = 55 | issue = 10| | | volume = 55 | issue = 10| page = 184 | ||
| bibcode = 2019EPJA...55..184I | | bibcode = 2019EPJA...55..184I | ||
| arxiv = 1904.11512 | | arxiv = 1904.11512 | ||
| Line 141: | Line 141: | ||
| year = 2016 | | year = 2016 | ||
| volume = 116 | issue = 5 | | volume = 116 | issue = 5 | ||
| | | article-number = 052501 | ||
| doi = 10.1103/PhysRevLett.116.052501 | | doi = 10.1103/PhysRevLett.116.052501 | ||
| pmid = 26894705 | | pmid = 26894705 | ||
| Line 148: | Line 148: | ||
Evidence for unbound clusters of 4 neutrons resonances in the disintegration of [[beryllium]]-14 nuclei,<ref name="marques02"/> in <sup>8</sup>He-<sup>8</sup>Be interactions,<ref name="Kisamori"/> and collisions of <sup>4</sup>He nuclei give an estimated lifetime around 10<sup>−22</sup> seconds.<ref name=DuerNature2022>{{Cite journal |last1=Duer |first1=M. |last2=Aumann |first2=T. |last3=Gernhäuser |first3=R. |last4=Panin |first4=V. |last5=Paschalis |first5=S. |last6=Rossi |first6=D. M. |last7=Achouri |first7=N. L. |last8=Ahn |first8=D. |last9=Baba |first9=H. |last10=Bertulani |first10=C. A. |last11=Böhmer |first11=M. |last12=Boretzky |first12=K. |last13=Caesar |first13=C. |last14=Chiga |first14=N. |last15=Corsi |first15=A. |date=2022-06-23 |title=Observation of a correlated free four-neutron system |journal=Nature |language=en |volume=606 |issue=7915 |pages=678–682 |doi=10.1038/s41586-022-04827-6 |issn=0028-0836 |pmc=9217746 |pmid=35732764|bibcode=2022Natur.606..678D }}</ref> | Evidence for unbound clusters of 4 neutrons resonances in the disintegration of [[beryllium]]-14 nuclei,<ref name="marques02"/> in <sup>8</sup>He-<sup>8</sup>Be interactions,<ref name="Kisamori"/> and collisions of <sup>4</sup>He nuclei give an estimated lifetime around 10<sup>−22</sup> seconds.<ref name=DuerNature2022>{{Cite journal |last1=Duer |first1=M. |last2=Aumann |first2=T. |last3=Gernhäuser |first3=R. |last4=Panin |first4=V. |last5=Paschalis |first5=S. |last6=Rossi |first6=D. M. |last7=Achouri |first7=N. L. |last8=Ahn |first8=D. |last9=Baba |first9=H. |last10=Bertulani |first10=C. A. |last11=Böhmer |first11=M. |last12=Boretzky |first12=K. |last13=Caesar |first13=C. |last14=Chiga |first14=N. |last15=Corsi |first15=A. |date=2022-06-23 |title=Observation of a correlated free four-neutron system |journal=Nature |language=en |volume=606 |issue=7915 |pages=678–682 |doi=10.1038/s41586-022-04827-6 |issn=0028-0836 |pmc=9217746 |pmid=35732764|bibcode=2022Natur.606..678D }}</ref> | ||
These discoveries should deepen our understanding of the nuclear forces.<ref name="sciencealert">{{cite web|url=https://www.sciencenews.org/article/physicists-find-signs-four-neutron-nucleus|title=Physicists find signs of four-neutron nucleus|date=2016-02-24|access-date=2017-06-27|archive-date=2017-07-29|archive-url=https://web.archive.org/web/20170729030228/https://www.sciencenews.org/article/physicists-find-signs-four-neutron-nucleus|url-status=live}}</ref><ref>{{cite journal|first=Nigel|last=Orr|title=Can Four Neutrons Tango?|journal=[[Physics (American Physical Society magazine)|Physics]]|volume=9|date=2016-02-03| | These discoveries should deepen our understanding of the nuclear forces.<ref name="sciencealert">{{cite web|url=https://www.sciencenews.org/article/physicists-find-signs-four-neutron-nucleus|title=Physicists find signs of four-neutron nucleus|date=2016-02-24|access-date=2017-06-27|archive-date=2017-07-29|archive-url=https://web.archive.org/web/20170729030228/https://www.sciencenews.org/article/physicists-find-signs-four-neutron-nucleus|url-status=live}}</ref><ref>{{cite journal|first=Nigel|last=Orr|title=Can Four Neutrons Tango?|journal=[[Physics (American Physical Society magazine)|Physics]]|volume=9|date=2016-02-03|article-number=14|doi=10.1103/Physics.9.14|bibcode=2016PhyOJ...9...14O|doi-access=free}}</ref> | ||
== See also == | == See also == | ||
Latest revision as of 10:39, 3 October 2025
Template:Short description The tetraneutron is considered an unbound isotope with a lifetime around 10−22 seconds.[1]Template:Rp The stability of this cluster of four neutrons is not supported by current models of nuclear forces.[2] Recent empirical evidence is "consistent with a quasi-bound tetraneutron state existing for a very short time".[3]
Marqués' experiment
Francisco-Miguel Marqués and co-workers at the GANIL accelerator in Caen used a particle accelerator to fire atomic nuclei at carbon targets and observed the "spray" of particles from the resulting collisions.[4] In this case the experiment involved firing beryllium-14, boron-15 and lithium-11 nuclei at a small carbon target, the most successful being beryllium-14. This isotope of beryllium has a nuclear halo that consists of four clustered neutrons; this allows it to be easily separated intact in the high-speed collision with the carbon target.[5] Current nuclear models suggest that four separate neutrons should result when beryllium-10 is produced, but the single signal detected in the production of beryllium-10 suggested a multineutron cluster in the breakup products; most likely a beryllium-10 nucleus and four neutrons fused together into a tetraneutron.
A later analysis of the method used in the Marqués' experiment suggested that the detection mechanism was unlikely[6] but the suggestion was refuted,[7] and attempts to reproduce these observations with different methods have not successfully detected any neutron clusters.[8]
Consequences of hypothetical bound tetraneutrons
If, however, the existence of bound tetraneutrons were ever independently confirmed, considerable adjustments would have to be made to current nuclear models. Bertulani and Zelevinsky proposed that, if it existed, the tetraneutron could be formed by a bound state of two dineutron systems.[9] However, attempts to model interactions that might give rise to multineutron clusters have failed,[10][11][12] and it "does not seem possible to change modern nuclear Hamiltonians to bind a tetraneutron without destroying many other successful predictions of those Hamiltonians. This means that, should a recent experimental claim of a bound tetraneutron be confirmed, our understanding of nuclear forces will have to be significantly changed."[13] Further work[14] in 2019 suggests potentially observable consequences in neutron star crusts, if the tetraneutron exists.
Evidence for very short lived resonances
In 2016, researchers at RIKEN in Wakō, Japan observed evidence that the tetraneutron exists briefly as a resonance. They fired a beam of neutron-rich helium-8 nuclei (two protons and six neutrons) at a liquid target composed of helium-4 (two protons and two neutrons). Occasionally, the reaction produced beryllium-8 nuclei with four protons and four neutrons, leaving four neutrons unaccounted for. If a four-neutron nucleus did occur, it lasted for about 10−21 seconds before decaying into other particles.[15][16][17]
Evidence for unbound clusters of 4 neutrons resonances in the disintegration of beryllium-14 nuclei,[5] in 8He-8Be interactions,[17] and collisions of 4He nuclei give an estimated lifetime around 10−22 seconds.[3] These discoveries should deepen our understanding of the nuclear forces.[18][19]
See also
Notes
External links
- Announcement of possible tetraneutron observations
- Announcement of possible tetraneutron observations Template:Webarchive Template:In lang
- Announcement of possible tetraneutron observations (Internet Archive)
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