Shaking the electron has strengthened quantum mechanics

Aug 24, 2012
Shaking the electron has strengthened quantum mechanics

Decays of atomic nuclei are potential sources of information on fundamental phenomena occurring in the quantum world. Unfortunately, it is a rather difficult task to model such processes. However, NCBJ physicists have successfully simulated the process of neutron-proton conversion in a singly ionized 6He atom nucleus, and correctly predicted its impact on the atomic orbital sole electron. Theoretical calculations were recently confirmed by an experiment performed in the GAEN accelerator centre in Caen (France).

Nucleus of a 6He ion is composed of two protons and four neutrons. In a singly ionized ion the nucleus is orbited by a single electron. Surplus of neutrons makes such nuclei unstable—they undergo the so-called beta-minus decays in which one of the is transformed into a proton. To preserve electric charge, an electron is emitted from the decaying nucleus. Each emitted electron is accompanied by an electron anti-neutrino. In effect, a stable 6Li nucleus (still orbited by a single electron) is produced.

"During each beta-minus decay, the orbiting (atomic) electron is impacted because of two reasons. Firstly, the total electric charge of the nucleus is changing since three protons are suddenly appearing in place of two . Secondly, a negatively charged emitted electron is flying nearby. It is plenty of stimulation for the orbiting electron: One might say that it is shaken very strongly. As a result, it is excited to a higher orbital or completely struck out of the atom," explains Professor Zygmunt Patyk from NCBJ.

uses wave functions to describe particles. The functions may be used to calculate probabilities that the particle will take some determined states.

"The 6He ion selected for calculations is almost a textbook case: single electron orbiting within a relatively simple potential well of the nucleus," said Dr. Katarzyna Siegień-Iwaniuk from NCBJ.

Electrons emitted by the decaying nuclei move at a speed close to the light velocity. They cross orbital electron clouds in times shorter than one billionth part of a nanosecond (i.e. 10-18 s). In quantum mechanics, problems with such short interactions are treated by finding a superposition of some final state wave functions (in our case: single electron within the 6Li ion) that jointly approximate the initial state wave function (in our case: single electron within the 6He ion). This trick is known as the sudden approximation method. It has been applied for many years—almost from the days quantum mechanics was born—but has never been directly verified in any experiment.

Professor Patyk's team has been collaborating with teams of physicists working at GAEN accelerator centre in Caen (Normandie, France) for several years. Calculations performed by NCBJ physicists to the accuracy of four significant places yielded the 2.3% probability that beta-decay will be liberating the sole orbital electron of the 6He ion, i.e. will be producing a totally ionized lithium atom. To a comparable accuracy, that result was confirmed by some experiments performed at the French accelerator.

"Such a good agreement between theoretical predictions and experimental findings in such a simple (almost textbook) system is the first direct proof that the sudden approximation computational method utilized to solve quantum mechanics problems for almost a century is indeed correct," points out Professor Patyk.

NCBJ physicists have also managed to determine factors responsible for liberating the 6He sole orbital electron. The performed analyses have indicated that the ionization is caused in 99% cases by change of the nucleus total electric charge, and only in 1% cases by the fast electron emitted by the decaying nucleus.

Explore further: Researchers demonstrate ultra low-field nuclear magnetic resonance using Earth's magnetic field

Provided by Narodowe Centrum Badan Jadrowych

4.7 /5 (11 votes)

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User comments : 8

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Tektrix
1.7 / 5 (6) Aug 24, 2012
"Electrons emitted by the decaying nuclei . . ."

Actually, it's,"Electrons emitted *as a result of* the decaying nuclei . . ."
baudrunner
1 / 5 (3) Aug 24, 2012
"Such a good agreement between theoretical predictions and experimental findings in such a simple (almost textbook) system is the first direct proof that the sudden approximation computational method utilized to solve quantum mechanics problems for almost a century is indeed correct," points out Professor Patyk.
Why doesn't he just move on? I swear, skeptics like him are slowing scientific progress, let alone wasting valuable research money.
barakn
4.4 / 5 (7) Aug 24, 2012
That's a meaningless semantic argument, Tektrix.
El_Nose
3 / 5 (2) Aug 24, 2012
No actually...

the nuclei is what emits the electron. So the original sentence stands as being correct. To say that it is more correct to say the electron is emitted as a result of the decaying nuclei is not correct either for what you are trying to imply. You should have said emitted from a nuclei that is in the process of decay.

And it still would have meant the same thing... just being pedantic.
vacuum-mechanics
1 / 5 (6) Aug 24, 2012
Decays of atomic nuclei are potential sources of information on fundamental phenomena occurring in the quantum world. Unfortunately, it is a rather difficult task to model such processes.

This is the problem of the conventional interpretation in which mathematic is dominate physics! May be this physical model could help to understand the matter;
http://www.vacuum...=9〈=en
jsdarkdestruction
Aug 25, 2012
This comment has been removed by a moderator.
ValeriaT
1 / 5 (6) Aug 25, 2012
I'm not linking the same page mindlessly whole years as an explanation for everything. Such a spammers devalue the alternative approach to physics more, than the mainstream physicists.
Eoprime
4.4 / 5 (7) Aug 26, 2012
I'm not linking the same page mindlessly whole years as an explanation for everything. Such a spammers devalue the alternative approach to physics more, than the mainstream physicists.


I almost fell of my chair laughing...
jsdarkdestruction
3.9 / 5 (7) Aug 26, 2012
I'm not linking the same page mindlessly whole years as an explanation for everything. Such a spammers devalue the alternative approach to physics more, than the mainstream physicists.

that is exactly what youve been doing on here for years zephyr. how can you not see that?