Conventions

Conventions

N U C L E A R D A T A SHEETS CONVENTIONS USED ON N U C L E A R DATA SHEETS Units Level Scheme Symbols continued Energies ...

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N U C L E A R D A T A SHEETS

CONVENTIONS USED ON N U C L E A R DATA SHEETS

Units

Level Scheme Symbols continued Energies ................................. Cross sections ......................... Magnetic dipole moments ............ Electric quadrupule moments .......

MeV barns nuclear magnetons barns

I

88 1.2349

Radiation of which the existence or position on the level scheme is not well-established Adopted value of total beta-disintegration energy, 1.234 :t 0.009

? Question Marks These are used to show doubt, on the part of the authors quoted, as to the existence or assignment of a radiation,

Beta and gamma ray entering level are coincident with gamma ray leaving level

( ) Parentheses

3.7 x 10-2%, 7.3

(1.234)

See also Level Scheme Symbols.

a K = 0.003

a-transition with intensity 3.7 x 10-2% and hindrance factor 7.3. See data sheets on a-emitting nucleus for a-energies

591399

The energy of the ),-ray was not determined carefully by 59B99 when these authors measured the conversion coefficient. The value 1.234 was assigned by the compilers from results of other authors.

t+

0.55

0.404

t:/'--transition with end-point energy, 0.404 MeV, measured directly; intensity, 4% of decays, faun indirectly (usually from y-intensities, a more accurate method if there are several /J-groups); log [t = 8.5

(f~/f~ = 63)

The ratio of electron capture to positron emission was not measured but was taken from theory. (t2)C(d,p) ' (116)Sn(n,p ) 13-s In Natural-element targets were used but there are reasons to believe 12C and I trSn were the reacting isotopes. '* t 2C(d,p)" or " z i 6Sn(n,p),, means that enriched targets were used.

/

0.890

6 = e K + EL, the value for e L h a ~ n g been found with the help of the curve of Rose and Jackson, Phys. Rev. 76, 1549 (1949)

Strong ar-

The vertical line segment represents the energy 2"nc 2 = 1.022 MeV which must be added to the /3 + end-point energy to give the atomic-mass difference between parent t~nd daughter

j ~ = 4 t§ Strong arguments show the spin is 4; weak arguments suggest positive parity.

/

[ ] Brackets

0.119

Sloping Type (Italics) See also Level Scheme Symbols. 4.623

3 means 4.623 •

12 means 4.6 J: 1.2

0.665

Level of which the existence is not well-established Adopted position of neutron- or proton-separation energy Well-established level

% 3_

Ground-state or long-lived isomeric level

N u c l e a r Data

25, 3

y-transition with energy 0.665 MeV and intensity 25 transitions per 100 decays of parent to the right, 3 transitions per 100 decays of parent to the left. Transition intensity means total number of photons plus c e ' s

Level Scheme Symbols ......

80%, 6.3

c-transition with energy determined directly from end point of ),-continuum (to which is added Kshell electron binding energy) or from L-, K-capture ratio; with intensity determined directly, by measurement of Xy-coincidences for example

7/2-[514] Nilsson asymptotic quantum numbers, K~[N n z A]

4.6

0.5% t * (56% E) 4.6

fl+-transition with directly measured end-point energy 0.890 MeV, directly measured /3 Lintensity 0.5% of decays, computed E-intensity 56%, log It = 4.6

J" = (I/2,3/2)Weak arguments limit the spin to 1/2 or 3/2. guments indicate negative parity.

(4%, 8.5)

B2-3-vi

Number per 100 d!sintegrations of a nuclear level. Spin which was measured by atomic-beam method or other direct method