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Nov. 10, 2011, RIKEN. Atomic Mass Evaluation. WANG Meng 王 猛. Background, present status method, discussion……. H.Schatz et al., PRL 86(2001)3471. Mass measurement: inertial mass energy. Relative Measurement. The AME2003 A.H. Wapstra, G. Audi , C. Thibault, Nucl. Phys. A
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Nov. 10, 2011, RIKEN Atomic Mass Evaluation WANG Meng 王 猛 Background, present status method, discussion……
H.Schatz et al., PRL 86(2001)3471
Mass measurement: • inertial mass • energy Relative Measurement
The AME2003 A.H. Wapstra, G. Audi , C. Thibault, Nucl. Phys. A 729 (2003) 129
50 years of mass evaluations The more recent history of atomic masses can be found in: Georges Audi “The history of nuclidic masses and of their evaluation” International Journal of Mass Spectrometry 251 (2006) 85–94 An early (perhaps the first) attempt for a mass evaluation is M.S. Livingston, H.A. Bethe, “Nuclear Physics, C. Nuclear dynamics, experimental”, Rev. Mod. Phys. 9 (1937) 245, XVIII. Nuclear masses; p. 366 The authors combined data from mass spectrometry and nuclear reaction and decay data up to 40Ar. In the early 1950’s it was found that the many relations (direct and indirect) overdetermined the mass value of many nuclides. Aaldert H. Wapstra established a procedure using a least-squares method to solve the problem of overdetermination. The first table of atomic masses using this method is dated 1955.
List of Atomic Mass Evaluations A.H. Wapstra, Physica 21 (1955) 367 + 385; J.R. Huizenga, Physica 21 (1955) 410 F. Everling, L.A. König, J.H.E. Mattauch, A.H. Wapstra, Nucl. Phys. 18 (1960) 529 L.A. König, J.H.E. Mattauch, A.H. Wapstra, Nucl. Phys. 31 (1962) 18 J.H.E. Mattauch, W. Thiele, A.H. Wapstra, Nucl. Phys. A67 (1965) 1 + 32 + 73 A.H. Wapstra & K. Bos, At. Data Nucl. Data Tables 19 (1977) 175 A.H. Wapstra, G. Audi & R. Hoekstra, Nucl. Phys. A432 (1985) 185 G. Audi & A.H. Wapstra, Nucl. Phys. A 565 (1993) 66 C. Borcea, G. Audi, A.H. Wapstra & P. Favaron, Nucl. Phys. A 565 (1993) 158 G. Audi, A.H. Wapstra & M. Dedieu, Nucl. Phys. A 565 (1993) 193 G. Audi & A.H. Wapstra, Nucl. Phys. A 595 (1995) 409 G. Audi, O. Bersillon, J. Blachot & A.H. Wapstra, Nucl. Phys. A 624 (1997) 1 G. Audi, O. Bersillon, J. Blachot & A.H. Wapstra, Nucl. Phys. A 729 (2003) 3 A.H. Wapstra, G. Audi & C. Thibault, Nucl. Phys. A 729 (2003) 129 G. Audi, A.H. Wapstra & C. Thibault, Nucl. Phys. A 729 (2003) 337
Collaborators Coordinator Georges Audia Contributors Meng Wanga,b,e, Xing Xub, Jean Blachota, Berndt Pfeiffercc , Filip Kondevd a. CSNSM-Orsay b. IMP-Lanzhou c. GSI-Darmstadt d. ANL-Argonne e. MPIK-Heildelberg
Preview of Ame2013 and Nubase2013 G.Audi & M.Wang Intensive work is continuing for the preparation of the two “horizontal” evaluations Ame2013 and Nubase2013. These two evaluations are foreseen to be published by the end of 2012 or the beginning of 2013.In the mean time, given the fact that the previous evaluations are already more than 7 years old, and that many demands have been expressed by our colleagues for some updated tables, we have decided to release now a series of tables and figures containing today's status of our work. These tables will certainly appear to be different from the final tables that we will publish as Ame2013 & Nubas2013, however, compared to the 2003 publications, so many changes and improvements are included that we think they can answer already most of the demands from many of our colleagues. WARNING : no details on how the new values were derived will accompany the present tables; all details about our final analysis and choices will be given in the coming Ame2013 and Nubas2013 publications.The Ame2011-preview is given here as 3 tables and a series of figures that can be downloaded from :http://amdc.in2p3.fr/masstables/Ame2011int/filel.htmlThe Nubase2011-preview appears in the Nucleus display that can be found as:http://amdc.in2p3.fr/nucleus/nucWxp2.exeor http://amdc.in2p3.fr/nucleus/nucWxp3.exe for the 3D versionAll values distributed above are given with the “not publishedstatus”. When needed they can be quoted as : Private Communication April 2011 by Georges Audi and Wang Meng
Precision of Q-values and masses Q-values Ame’2003 10762 experimental data 4943 used 2228 gs masses 203 isomers Ame’2010 12220 experimental data 5092 used 2341 gs masses 220 isomers masses
The procedure of AME • Experimental Data Collection and Evaluation • Treatment of Data Least Squares Method Flow of Information Consistency of Data • Regularity of the Mass Surface From S2n – S2p – Qα - …. From difference with a smooth function
Statistics 3597 NUCLEI ACCEPTED : 967 Primaries in 1554 Equations with 4005 Coefficients
Data Evaluation • Data collection • Careful reading Evaluate or re-evaluate Calibration procedures & calibrants Accuracies of the measurement Examine spectra Select PRIMARY information • Comparison To previous results --direct results – combination of other results To estimates from extrapolations To estimates from models • Dialogue
from Tommi Eronen tommi.o.eronen@gmail.com to meng wang <amdc.wang@gmail.com>date Fri, Oct 28, 2011 at 6:56 AM subject Re: data in your paper PRC83, 055501mailed-by gmail.comsigned-by gmail.com Dear Dr. Meng,you are absolutely right! I just checked from my spreadsheets thatindeed the correct frequency ratio is the one you suggest, so thereis one "1" missing. Thanks for noticing it! I will inform PRC editorsabout this.I also see that our final manuscript versio has the "1" in but proofsdon't have it and apparently we were blind to see the difference.Best wishes,Tommi2011/10/27 meng wang <amdc.wang@gmail.com>: > Dear Dr. Eronen,> I'm working on including the data from your paper> Phys. Rev. C 83, 055501 (2011) into AME.> While I found out from the frequency ratio of> 10C/10B = 1.000 391 57(9) as listed in table 2,> I could only get the corresponding Qec= 3651.97 keV,> different with your value.> I guess there is a typo: one "1" was missed> in the table, so the true value for freq. ratio> should be 1.000 391 157(9).> Could you please check this case?> Best regards,> Meng>
example 3 PHYSICAL REVIEW C 81, 055503 (2010) C. Wrede et al. “the ground-state masses of the respective daughter nuclei 20Na, 24Al, 28P, and 32Cl have been determined by measuring the (3He,t ) reactions leading to them with the 36Ar(3He,t )36K reaction as a calibration.”
On Fri, Apr 15, 2011 at 3:05 PM, meng wang amdc.wang@gmail.com > wrote:Dear Dr. Wrede, we are working on the atomic mass evaluation and preparing a new mass table. We are studying your paper PRC 81,055503, where the Q values of (3He,t) reactions on different target are measured. In table 4 of this paper, the masses are given for corresponding nuclei. We prefer to use the primary information so that the masses can be recalibrated automatically for any changes. While the information is not present in the paper, we tried our best to reconstruct theequations :20Ne(3He,t)20Na - 36Ar()36K : -1078.0 (1.0)24Mg(3He,t)24Al - 36Ar()36K : -1071.5(1.0)28Si(3He,t)28P - 36Ar()36K : -1530.6(1.1)32S(3He,t)32Cl - 36Ar()36K : 133.0(1.1) The uncertainty of 0.4 keV for 36K has been deconvoluted to obtain the uncertainties listed above. Could you please check if the treatment is good and give your comment? Best regards, Meng WANG and Georges Audi
Dear Meng,Thank you for your inquiry. I checked your numbers by using an extra significant digit or two at every point in the calculation (these digits are not all available in the paper). For example, I used 0.39 keV for the 36K uncertainty. I found that your numbers are all accurate, except the one for A=20. In that case I get -1078.1 (1.1) keV. In the case of A=24, I get an uncertainty of 1.047 keV, which is close to rounding either way. I suppose it technically rounds to 1.0 keV, as you already had.Here is a summary of my Q-value differences in keV to one extra digit:20Ne(3He,t)20Na - 36Ar()36K : -1078.06 (1.06)24Mg(3He,t)24Al - 36Ar()36K : -1071.48 (1.05)28Si(3He,t)28P - 36Ar()36K : -1530.58 (1.10)32S(3He,t)32Cl - 36Ar()36K : 133.01 (1.10)I hope this information is helpful to you. Please let me know if you need more information. Thank you.Best regards,-Chris Wrede
Consistency of Data: Example 1
Example 2 In present AME, 168Yb-168Er = 1420(4) keV
QEC 80Sr-85Rb.941 7531 8 7523.372 3.718 -1.0 -1- hMA2 1.0 94Ot01 80Sr-85Rb.941 7513 14 7523.372 3.718 .7 U HMA8 1.0 05Si34 80Sr-85Rb.941 7521.3 4.2 7523.372 3.718 .5 -1- HSH1 1.0 11Ha08 80Y O-96Mo 24594.6 6.7 2 HJY1 1.0 06Ka48 80Y(B+)80Sr 6952 152 9163.100 7.297 14.5F F hBNL 81Li12 80Y(B+)80Sr 6934 242 9163.100 7.297 9.2F F hOrs 82De36 80Y(B+)80Sr 6200 600 9163.100 7.297 4.9F F h 96Sh27,* 80Y(B+)80Sr 9140 400 9163.100 7.297 .1 Z m S-sugg *80Y(B+)80Sr F: below lower limit Q->8929(23) keV determined by ref H 03Ba18**
Local mass evaluation A.Kankainen et al., Phys.Rev. C 82, 034311 (2010)
Correlations of input data Sz. Nagy et al., Europhys. Lett. 74(3), 404-410. Peter J. Mohr,† Barry N. Taylor,‡ and David B. Newell REVIEWS OF MODERN PHYSICS, VOLUME 80, APRIL–JUNE 2008 CODATA recommended values of the fundamental physical constants: 2006* Relative uncertainties
Change in the predicted abundances when keeping the same stellar parameters(neutron density n_n, temperature and process duration). The experimentalmasses from AME are superimposed on the FRDM mass model [1997Möller]: AME2003 masses (black line) and AME2010 (red line). Crosses and error bars are for the observed abundances in the solar system [2003Lodders]. The data arenormalized to the A=130 observed abundance.