Confirming Nuclei Deformation: Theory & Experimental Considerations

Join the discussion
Ask a follow-up here, or get your own question answered by working scientists, mathematicians and engineers — people, not an autocomplete.
Real named experts · corrections over time · the nuance an AI answer skips
2 replies · 2K views
Dilema
Messages
37
Reaction score
1
Literature survey on Nuclei deformation I found theoretical calculations and prediction however I could not find experimental considerations.
1. How nuclei deformation confirmed?
2. Is it possible to consider deformation modulus constant that equivalent to Yang Modulus in mechanics? Are there such estimations? or calculations?
 
Physics news on Phys.org
Dilema said:
1. How nuclei deformation confirmed?
Let me try a blind shoot: by deformed nuclei you mean nuclei that are not spherically symmetric?
First of all this is a consequence of the appearence of angular momentum.. a spherically symmetric wavefunction is invariant under any kind of rotational transformation...
Secondly, recall from electrodynamics that a deformed shape of charge (nuclei contain protons) give rise to higher order-terms in the multipole expansion... so you can have quadrapole fields etc...

Dilema said:
Is it possible to consider deformation modulus constant that equivalent to Yang Modulus in mechanics?
I don't think you can do it... what is deformed is the probability distribution function... it's not some kind of "box" that can feel stress or anything. Of course you can make analogues but they won't tell you much (I guess).
 
Dilema said:
Literature survey on Nuclei deformation I found theoretical calculations and prediction however I could not find experimental considerations.
1. How nuclei deformation confirmed?
2. Is it possible to consider deformation modulus constant that equivalent to Yang Modulus in mechanics? Are there such estimations? or calculations?

Deformation can be observed by the level structure. For example, the existence of a rotational band is evidence of deformation. As an example, check out the ground state band of 154Gd (just chosen randomly as a nice midshell deformed nucleus. This is a screenshot from NNDC http://www.nndc.bnl.gov/chart/reCenter.jsp?z=64&n=90). The presence of rotational bands are indicative of deformed nuclei.(ETA: Of course there are others, e.g. transition strengths, intruder states, vibrational bands)
Screenshot from 2016-10-20 10:37:04.png


I'm surprised you did not find any experimental work, considering that it is an extremely active field. Here's a (very random) selection of papers that concern experimental data for deformed nuclei. (Some of these are theory papers, but do include experimental data. I've literally just randomly grabbed these from the recent PRC issues and a workshop I was just at. These do not represent a complete coverage of the field in any way)

http://journals.aps.org/prc/abstract/10.1103/PhysRevC.94.021301
http://journals.aps.org/prc/abstract/10.1103/PhysRevC.93.031302
http://www.sciencedirect.com/science/article/pii/037015739290095H
http://journals.aps.org/rmp/abstract/10.1103/RevModPhys.83.1467
http://www.sciencedirect.com/science/article/pii/S0370269315009120
http://journals.aps.org/prc/abstract/10.1103/PhysRevC.94.021301
http://journals.aps.org/prc/abstract/10.1103/PhysRevC.94.044307
http://journals.aps.org/prc/abstract/10.1103/PhysRevC.94.044314

I would encourage you to look at chapter 5 of Krane's Introductory Nuclear Physics text. If you don't have a copy of Krane, any introductory nuclear text should cover the basics of deformed nuclei.
 
  • Like
Likes   Reactions: vanhees71