EkEk ∆ δ A I of rigid Gap parameters from moments of Inertia
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Transcript of EkEk ∆ δ A I of rigid Gap parameters from moments of Inertia
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Triune Pairing RevelationLuciano G. Moretto&Augusto Macchiavelli
even-oddmass differences Critical temperatures from level densitiesSuperfluid momentsof inertiaAnomalous Quasi Particle Spectrum Ek
Ground State Masses
Hence even odd mass differences A
Anomalous Moments of Inertia in rotational nucleiI
of rigid
Gap parameters from moments of InertiaMemories.Gilbert and Cameron0lnElnE/T
BnLow energy level counting ..exponential?Neutron resonances . 1 pointHigher energy..Fermi gas
Global Solution : matching a Fermi Gas to an exponential dependence
Away from shells TG.C. TCr pairing = 2/3.5
Level densities, actinides6
Universal 1st Order Low Energy Phase Transition in Atomic Nuclei Luciano G. Moretto Hallmark of 1st order phase transition in micro-canonical systems?
Linear Dependence of Entropy with Energy !
or
(E)0510E (MeV)This is universally observed in low energy nuclear level densitiesT is the micro-canonical temperature characterizing the phase transitionEnergy goes in, Temperature stays the sameCan a thermostat have a temperature other than its own?
Is T0 just a parameter?
According to this, a thermostat, can have any temperature lower than its own!
T = Tc = 273Kor0 T 273K?8What causes the phase transition? In non magic nuclei Pairing
In magic nuclei Shall gap
= 1.76 TCrBCS Phase TransitionTCrT02nd orderNearly 1st order?
Fixed energy cost per quasi particle up to criticality : little blocking ? # quasi particle at TCr
Energy at criticality!Pairing: Fixed Energy cost/ quasi particle up to TCR ! Is this consistent with blocking?
goes down (k-) goes up Proof:=0ggxxfor x=0 ECr/QCr= 0for x>0 ECr/QCr 0
1st order phase transition implies two phases
Superfluid phase gas of independent quasi particles superfluid
What fixes the transition temperature?constant entropy per quasi particle Remember Sackur Tetrode
Entropy / Quasi Particle
Testing the picture:Even-Odd horizontal shift.
should be compared with even-odd mass differences
b) Relationship between the above shift and the slope 1/T
c) Vertical shift or entropy excess
Low energy level densities for nuclei away from shells vademecum for beginners..Get TCr from =12/A1/2
Write ln(E)=S(E)=E/T
Shift horizontally by or 2 for odd or odd-odd nuclei Ek
Ek
Pairing
Shell Model
Spectra with any gap
quasi particles vacuum N slots
Entropy/particle
Let us compare.
Entropy/ quasi particle
Good enough!!!!6-7 levels/ quasi particle
ConclusionsThe universal linear dependence of S=ln with E at low energies is a clear cut evidence of a first order phase transition
In non magic nuclei the transition is due to pairing. The coexisting phases are a) superfluid; b) ideal gas of quasi particles
In magic nuclei the transition is due to the shell gap . AD MULTOS ANNOS, ALDO.WITH FRIENDSHIPLow Energy Level DensitiesEln
Condensation energyGilbert and Cameron did empirically the match between linear and square root dependence.
In so doing they extracted TCR !
Memories.Gilbert and Cameron0lnElnE/T
BnLow energy level counting ..exponential?Neutron resonances . 1 pointHigher energy..Fermi gas
Global Solution : matching a Fermi Gas to an exponential dependence
Away from shells TG.C. TCr pairing = 2/3.53