Lone neutrons do n’t have much of a life-time . alfresco of an atom ’s lens nucleus , they quicklydecayto other subatomic particles . However , the precise survival metre of a free neutron before its dissolution is not precisely known despite decades of research .
In a bid to end this stalemate , researchers have turn from the science laboratory to the sky for their next curing of measurements . Using data gathered by NASA ’s MErcury Surface , Space ENvironment , GEochemistry , and Ranging(MESSENGER ) spacecraft , the team estimated a neutron ’s lifetime to be around 780 seconds , with an misplay of 60 seconds on either side . Whilst this name itself does not bid huge clarity , its contemporaries has show the viability of this new spaceward approaching .
“ This is the first time anyone has ever measured the neutron lifetime from blank , ” lead author Jack Wilson , a scientist at Johns Hopkins Applied Physics Laboratory ( APL ) , US , say in astatement . “ It proves the feasibility of this method , which could one day be the agency to resolve this anomalousness . ”
The two methods antecedently employ by researchers have produce conflicting results . In the “ bottle ” proficiency , neutrons trap by magnetic fields in a “ bottleful ” are periodically counted to cover how long they last . The “ radio beam ” experiment , on the other hired man , tally one of the particle ’s decay product ( protons ) that emerges from a irradiation of neutrons . come in at 879 second and 888 endorsement , severally , this discrepancy is significant when compared to the measurements ’ uncertainties .
However , scientists have been looking since 1990 to a third method – quad . Although no specific mission has ever been establish to measure a neutron ’s life-time , a neutron spectrometer onboard the MESSENGER spacecraft offer up the correct tools for the job . On its way to its destination in the late 2000 ’s , MESSENGER was able to find neutrons that had been ejected from Venus ’ atm by incoming cosmic rays . These neutron were counted over a range of altitudes , as the high the neutron travel , the longer it had pull through .
“ It ’s like a large bottle experiment , but instead of using wall and magnetic theatre of operations , we use Venus ’ gravitational attraction to confine neutron for sentence corresponding to their lifespan , ” Wilson said .
Comparing MESSENGER ’s measuring with calculate manikin of different neutron lifetimes , yield a ripe match of 780 seconds ( 13 instant ) . When uncertainties and statistical error are accounted for this estimation agrees with the values obtained from both the bottleful and beam method .
“ This resolution picture that even using data from a military mission design to do something entirely different , it ’s still possible to quantify the neutron lifespan from space , ” co - author Jacob Kegerreis , a research worker at Durham University , UK , said in astatement .
In their paper print inPhysical Review Research , the writer argue that if a dedicated mission were launched , possibly to Venus where its thick aura and large mass could efficaciously trap neutrons , they would be able to raise the most exact measurement on a neutron ’s lifetime yet . later on , this could help our savvy of how element formed after the Big Bang .
“ We ultimately want to contrive and build a spacecraft instrument that can make a high-pitched - precision measurement of the neutron life-time , ” Wilson said .
