q-deformed pairing-vibrations

Boson creation operators constructed from linear combinations of q- deformed zero coupled nucleon pair operators acting on the nucleus (A,0), are used to derive pp-RPA equations. The solutions of these equations are the pairing vibrations in (A${\underline

q-deformedpairing-vibrations

S.ShellySharma

Depto.deF´isica,UniversidadeEstadualdeLondrina,

86051-970-Londrina,Parana,Brazil

N.K.Sharma

Depto.deMatem´atica,UniversidadeEstadualdeLondrina,

86051-970-Londrina,Parana,Brazil

Abstract

Bosoncreationoperatorsconstructedfromlinearcombinationsofq-deformedzerocouplednucleonpairoperatorsactingonthenucleus(A,0),areusedtoderivepp-RPAequations.Thesolutionsoftheseequationsarethepairingvibrationsin(A+arXiv:nucl-th/9410020v1 12 Oct 1994σ(0+

1)=0.45arewellreproduced.Thecriticalvalueof

pairinginteractionstrengthforwhichphasetransitiontakesplace,isseentobelowerfordeformedzero-couplednucleonpaircondensatewithτreal,supportingourearlierconclusionthattherealdeformationsimulatesthetwo-bodyresidualinteraction.Forτpurelyimaginaryastrongerpairinginteractionisrequiredtobringaboutthephasetransition.Thee ectofimaginarydeformationisakintothatofanantipairingtyperepulsiveinteraction.

Usingdeformedzerocoupledquasi-particlepairs,adeformedversionofQuasi-bosonapproximationfor0+statesinsuperconductingnucleiisdeveloped.Forthetestmodelof20particlesintwoshells,theresultsofq-deformedbosonandquasi-bosonapprox-imationshavebeencomparedwithexactresults.Itisfoundthatthedeformatione ectivelytakesintoaccounttheanharmonicitiesandmaybetakenasaquantitativemeasureofthecorrelationsnotbeingaccountedforinacertainapproximatetreatment.