ADOPTED LEVELS for 202Ra
Author: F.G. Kondev | Citation: Nucl. Data Sheets 196, 342 (2024) | Cutoff date: 1-Sep-2023
Full ENSDF file | Adopted Levels (PDF version)
| S(n)= 10933 keV 25 | S(p)= 1803 keV 18 | Q(α)= 7880 keV 7 | |||
| Reference: 2021WA16 |
| E(level) (keV) | Jπ(level) | T1/2(level) |
| 0 | 0+ | 3.8 ms +13-8 % α = 100 |
Additional Level Data and Comments:
| E(level) | Jπ(level) | T1/2(level) | Comments |
| 0 | 0+ | 3.8 ms +13-8 % α = 100 | Eα=7727 keV 7 (2014Ka23), 7740 keV 20 (2005Uu02) and 7860 keV 60 (1996Le09). |
2014Ka23: 202Ra produced using the 149Sm(56Fe,3n) reaction, E(56Fe)=249 MeV. Target=370 μg/cm2-thick enriched to 96.9% in 149Sm, with 40μg/cm2-thick carbon backing and covered with a 10 μg/cm2-thick layer of carbon, and mounted on a rotating wheel. Detectors: SHIP recoil separator, 16-strip position sensitive Si detectors (PSSD), six Si strip detectors to detect escaping α particles and one HPGe clover detector behind the PSSD. Measured: recoil-α-α-α(t) coincidences. Sixteen quadruple (recoil-α1-α2-α{-3) events: 7722 keV (α1, 202Ra), 7198 keV (α2, 198Rn) and 6846 keV (α3, 194Po) were observed.
2005Uu02: 202Ra was produced by 141Pr(63Cu,2n) with 1 mg/cm2 target and 278 to 288-MeV beam at JYFL. Reaction products were separated by the RITU gas-filled separator, and implanted into a position-sensitive Si detector. Measured: recoil-α-α-α(t) coincidences. One quadruple (recoil-α1-α2-α{-3) event 7740 keV (α1, 202Ra), 2285 keV (escaped α2, 198Rn) and 6843 keV (α3, 194Po) was observed.
1996Le09: 202Ra was produced by 170Yb(36Ar,4n) with 360 μg/cm2 target (72% 170Yb, 18% 171Yb, 5% 172Yb and <3% 168Yb, 173Yb, 174Yb and 176Yb each) and 201-MeV beam at JYFL. Reaction products were separated by the RITU gas-filled separator and implanted into a position-sensitive Si detector. One quadruple (recoil-α1-α2-α{-3) (Eα2, Eα3 missing) event 7860 keV 60 (α1, 202Ra) was observed. The assignment to 202Ra decay is tentative.
Q-value: S(2p)=1503 16, Q(εp)=5893 18 (2021Wa16)