amilan17 commented 3 years ago

Branch

https://github.com/wmo-im/wmds/blob/issue356/tables_en/1-01-01.csv

Summary and Purpose

Review terms and add to WMDS codes if needed.

The TT for TDCF is proposing two new terms for radionuclides: • Tellurium 131 • Neodymium 137

https://github.com/wmo-im/CCT/issues/65

Stakeholder(s)

Proposal

name	description	tags
Tellurium [Te-131]	IUPAC: tellurium-131, PubChem CID: 6337051, CAS Number: 14683-12-6	radionuclide
Neodymium [Nd-137]	IUPAC: neodymium-137	radionuclide

Reason

To keep alignment with MoC CCT table....

Expected Impact of Change

MEDIUM

Inclusion of new code in OSCAR is uncomplicated.

amilan17 commented 3 years ago

@gaochen-larc Can you respond to this issue?

fstuerzl commented 3 years ago

@amilan17, @gaochen-larc, I've created a branch and updated the proposal, so that the variable names and descriptions align with the other radionuclide variables. As you seem I wasn't able to find a CAS number or a PubChem CID for Nd-137...

gaochen-larc commented 3 years ago

From the information I found, it appears that Nd-137 does not exist in natural environment. This raise a question if this variable should be added. Looking for clarifications...

"In 1970 137Nd was reported in “135mCe and 137mNd: Isomeric States in N = 77 Isotones” by Droste et al. [20]. The Dubna U-300 cyclotron accelerated 18O and 20,22Ne beams which bombarded tellurium and tin targets, respectively. 137Nd was produced in the fusion-evaporation reactions 119Sn(22Ne,4n), 122Sn(20Ne,5n), 122Sn(22Ne,7n), and 126Te(18O,7n). Conversion electron and γ-ray spectrometry was used to identify the isotope. “In all cases, γ-rays of 108, 177, 233 and 285 keV which all decay with the same half-life, T1/2 = 1.60±0.15 s were observed... That the new activity belongs indeed to the nucleide 137Nd is proved by (i) the energy difference of the K and L electron lines of the isomeric transition EKL = 37.0±0.8 keV as compared to the value 36.8 keV expected for Z = 60(Nd), and (ii) the shape of the excitation functions from which the number of evaporated neutrons can be determined” The reported half-life corresponds to an isomeric state and is currently the accepted value for this state. Previously the 55.0(15) m half-life of 136Nd had incorrectly been assigned to 137Nd [16]. A half-life of 35(5) m corresponding to the ground state was reported already in 1935 [21], but no mass assignment was made."

https://people.nscl.msu.edu/~thoennes/2009/neodymium-adndt.pdf

joergklausen commented 2 years ago

I believe we need a requirement to be expressed from CTBTO. If this is relevant for them, then we can include it, otherwise I would also not take it. I recommend Michel Mirsch (Michael.Mirsch@dwd.de) be invited to comment. He helped with a previous issue #212.