Download presentation
Presentation is loading. Please wait.
1
Soongsil University, Seoul, Korea
Nuclear Matrix Elements (NME) for Double Beta Decay (DBD) (based on Quasi-particle RPA) Myung-Ki Cheoun Department of Physics, Soongsil University, Seoul, Korea K.S.Kim, E. Ha, W.Y.So, C. Ryu… A.Faessler, F. Simkovic.. Int. Workshop on DBD, SNU
2
Contents 0. Motivation for DBD 1. Brief Introduction of QRPA
2. Ambiguities in NME for DBD 3. Uncertainties and their Correlations by NME in the analysis of DBD 4. Summary and Remarks Int. Workshop on DBD, SNU
3
0. Motivation for DBD Int. Workshop on DBD, SNU
4
But, DBD occurs in Nucleus.
Mayoron contribution ? But, DBD occurs in Nucleus. Ambiguities from the Structure should be pinned down !! Int. Workshop on DBD, SNU
5
Half lives for DBD can be factored by 3 ingredients !!
Int. Workshop on DBD, SNU
6
3 Main Transitions (Fermi, GT and Tensor) in the NME for DBD !!
Various Multipolarities High momentum transfer Int. Workshop on DBD, SNU 1 - 2 fm
7
Experimental Status No overlap !! => HM data ? More sensitive test
Experimental Results Range expected By Theo. NME and HM data Int. Workshop on DBD, SNU
8
1. Brief Introduction of QRPA
Int. Workshop on DBD, SNU
9
2. Ambiguities in NME for DBD
Int. Workshop on DBD, SNU
10
Even Even Int. Workshop on DBD, SNU
11
Quasi Boson Approx. ?? Int. Workshop on DBD, SNU
12
Int. Workshop on DBD, SNU
13
Int. Workshop on DBD, SNU
14
other multipole states ?
But How about other multipole states ? Int. Workshop on DBD, SNU
15
Int. Workshop on DBD, SNU
16
Int. Workshop on DBD, SNU
17
Int. Workshop on DBD, SNU
18
Int. Workshop on DBD, SNU
19
3. Uncertainties and their Correlations by NME in the analysis of DBD
Int. Workshop on DBD, SNU
20
Int. Workshop on DBD, SNU
21
Int. Workshop on DBD, SNU
22
Most 24 theo. Data are included Strong and positive Correlations !!
in 1 sigma error eclipse Strong and positive Correlations !! Int. Workshop on DBD, SNU
23
Estimation of neutrino mass
Int. Workshop on DBD, SNU
24
Int. Workshop on DBD, SNU
25
Comparison of half-lives in coupled nuclei
76Ge HM result Phase space and Theo. NME Theo. Error bars With correlations Int. Workshop on DBD, SNU
26
More sensitive test are
No overlap !! => HM data ? More sensitive test are necessary Int. Workshop on DBD, SNU
27
Prospective Sensitivities for DBD in future project !!
Reliable limits for DBD, if DBD exists !! !! Int. Workshop on DBD, SNU
28
4. Summary and Remarks Most of uncertainties from the nuclear structure in DBD could be pinned down, but parts of them are inescapable because of the original problem in the many body system of nucleons. Allowing the ambiguities as the error bars theoretical data for NME are strongly correlated within 1-3 sigma, even if include other model calculations. Mayorana neutrino mass can be deduced from HM data, but the lower limit masses by other data are not reached to the upper limit of HM data. Int. Workshop on DBD, SNU
29
4. By the correlation method in NME results and HM data, one can estimate half lives of other nuclei. Their results are dislocated from the present data. 5. Prospective half lives in promising future projects could allow reliable limits to this DBD problem, if DBD exists. 6. Not only DBD but also other related reactions could be very helpful for pinning down the ambiguities from NME. 7. Theoretical studies for NME should be go on not only for DBD but also for unstable nuclei playing important roles on the nucleosynthesis in the Universe. Int. Workshop on DBD, SNU
30
Thanks for your attention !!
감사합니다 !! Int. Workshop on DBD, SNU
31
Int. Workshop on DBD, SNU
32
Int. Workshop on DBD, SNU
33
Int. Workshop on DBD, SNU
34
Int. Workshop on DBD, SNU
35
Int. Workshop on DBD, SNU
36
Int. Workshop on DBD, SNU
37
The formula for computing the covariance of the variables X and Y is
with and denoting the means of X and Y, respectively. Mean vector and variance- covariance matrix for sample data matrix The results are: Thus, is the variance of the length variable, is the covariance between the length and the width variables, is the covariance between the length and the height variables, is the variance of the width variable, is the covariance between the width and height variables and is the variance of the height variable. Int. Workshop on DBD, SNU
38
Although the variance is intended to be an overall measure of spread,
The variance is roughly the arithmetic average of the squared distance from the mean. Squaring the distance from the mean has the effect of giving greater weight to values that are further from the mean. For example, a point 2 units from the mean adds 4 to the above sum while a point 10 units from the mean adds 100 to the sum. Although the variance is intended to be an overall measure of spread, it can be greatly affected by the tail behavior Int. Workshop on DBD, SNU
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.