Radioactive Decay
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Dataset #2:

Authors: J. K. TULI, G. REED, B. SINGH           Citation: Nuclear Data Sheets 93, 1 (2001)

Parent           Parent           Parent          Parent                                  GS-GS Q-value Daughter
                                                                    Decay Mode
Nucleus          E(level)           J"             T 1/2                                      (keV)     Nucleus
                                                                                                                    Decay
                                                                                                                   Scheme
  99                                                                                                      99
     Tc      14 2 . 6 8 3 2 1 1   1/2-        6.015 h 9          I T : 9 9 . 9 9 63 6 %                      Tc
  43                                                                                                      43


Electrons:

                Energy                         Intensity             Dose
                 (keV)                            (%)             ( MeV/Bq-s )


CE M                  1.6286 11               74.595 %           0.0012149
Auger L               2.17                    10.32 % 6          2 . 2 4 0 E - 4 14
Auger K             15.5                        2.05 % 4         3.17E-4 6
CE K              119.4670 12                   8.84 %           0.01056
CE K              121.59 3                      0.55 % 5         6.7E-4 6
CE L              137.4685 11                   1.07 %           0.00147
CE L              139.59 3                      0.172 % 16       2.40E-4 23
CE M              139.9670 14                   0.194 %          2.72E-4
CE NP             140.4430 22                   0.0374 %         5.25310E-5
CE M              142.09 3                      0.034 % 3        4.8E-5 5
CE NP             142.56 3                      0.0066 % 6       9.4E-6 9



Gamma and X-ray radiation:

             Energy                        Intensity             Dose
              (keV)                           (%)             ( MeV/Bq-s )


                   2.1726 4                6.201E-9 %          1.347E-13
XR l               2.42                    0.447 % 11          1.08E-5 3
X R k #2          18.251                   2.14 % 6            3.91E-4 11
X R k #1          18.367                   4.07 % 12           7.47E-4 21
X R k !3          20.599                   0.330 % 10          6.79E-5 20
X R k !1          20.619                   0.639 % 18          1.32E-4 4
X R k !2          21.005                   0.145 % 4           3.04E-5 8
                140.511 1                89.06 %               0.1251
                142.63 3                   0.0187 % 18         2.7E-5 3
A conversion electron is ejected by
a gamma photon from the nucleus
A conversion electron is ejected by
a gamma photon from the nucleus
A kα X-ray comes when an
electron from the L shell falls to
           the K shell
A kα X-ray comes when an
electron from the L shell falls to
           the K shell
An Auger electron is ejected by a
           kα X-ray
An Auger electron is ejected by a
           kα X-ray
Gamma decay comes when nucleus falls
from high energy state to low energy state
Gamma rays can be absorbed by electrons
in the atom
Conversion electron: Gamma ray ejects
electron
k-α, L-β X-ray radiation when electrons
from high shells fall to low shells
Auger electrons when k-α absorbed by
outer electrons, ejecting them.
Gamma decay comes when nucleus falls
from high energy state to low energy state
Gamma rays can be absorbed by electrons
in the atom
Conversion electron: Gamma ray ejects
electron
k-α, L-β X-ray radiation when electrons
from high shells fall to low shells
Auger electrons when k-α absorbed by
outer electrons, ejecting them.
Alpha decay energy
MP         (MD   MHe )                               11-34
                                                  c2
   Note that the mass of the two electrons in the He atom compensates for the fact
   that the daughter atom has two fewer electrons than the parent atom. Applying this
   to the example given in Equation 11-33, the mass of the 232Th atom is 232.038124 u
   The mass of the daughter atom 228Ra is 228.031139 u, and adding it to the 4.002603
   u mass of 4He, we get 232.033742 u for the total mass of the decay products
   Equation 11-34 then yields Q/c 2 0.004382 u, which, when multiplied by the con-
   version factor 931.5 MeV/c 2, gives Q          4.08 MeV. Thus, the rest energy of 232Th
   is greater than that of 228Ra 4He; therefore, 232Th is unstable toward spontaneous
      decay.
       The kinetic energy of the particle (for decays to the ground state of the daugh-
   ter nucleus) is slightly less than the decay energy Q because of the small recoil energy
   of the daughter nucleus. If the parent nucleus is at rest when it decays, the daughter



                      1600
                                                !286
Number of particles




                      1200                                                                            !61
                                                                                                                  !0


                      800
                                        !334
                                         !330
                      400        !
                             !376 342                  !247                !174                 !80
                                !350                                                                        !30
                                                 !280         !235                       !124

                                  5.70                   5.80                     5.90                  6.00
                                                                 Energy, MeV
Alpha decay when nucleus is too large
Alpha particles emitted at specific energies
Not dangerous from outside: can’t penetrate
skin
Dangerous when ingested/inhaled




Gamma decay comes when nucleus falls
from high energy state to low energy state
Gamma rays can be absorbed by electrons
in the atom
Conversion electron: Gamma ray ejects
electron
k-α, L-β X-ray radiation when electrons
from high shells fall to low shells
Auger electrons when k-α absorbed by
outer electrons, ejecting them.
Alpha decay when nucleus is too large
Alpha particles emitted at specific energies
Not dangerous from outside: can’t penetrate
skin
Dangerous when ingested/inhaled




Gamma decay comes when nucleus falls
from high energy state to low energy state
Gamma rays can be absorbed by electrons
in the atom
Conversion electron: Gamma ray ejects
electron
k-α, L-β X-ray radiation when electrons
from high shells fall to low shells
Auger electrons when k-α absorbed by
outer electrons, ejecting them.
_
n    p + e– + ν
p    n + e+ + ν
p + e–   n+ ν
                  n    ν




                  p+   β-
Dataset #3:

Author: E. BROWNE            Citation: Nuclear Data Sheets 82, 379 (1997)

Parent Parent Parent            Parent                      GS-GS Q-value Daughter
                                            Decay Mode
Nucleus E(level) J!              T1/2                           (keV)     Nucleus
                                                                                      Decay
  90                                                                        90       Scheme
  39
     Y        0        2-     64.00 h 21      "- : 100 %       2280.1 16
                                                                            40
                                                                               Zr



Beta-:

  Energy      End-point energy           Intensity        Dose
   (keV)           (keV)                    (%)        ( MeV/Bq-s )

   25.0 7         93.8 16                1.4E-6 % 3        3.5E-10 8
  185.6 10        519.4 16               0.0115 % 14       2.1E-5 3
  933.7 12 2280.1 16                  99.9885 % 14         0.9336 12



Mean beta- energy: 933.6 keV 12, total beta- intensity: 100.0000 % 20, mean beta- dose:
0.9336 MeV/Bq-s 12
Decay radiation
n
udd
            νe

            e+




       W+




u du
 p
Positron decay makes
back-to-back photons

        –
            +

                          TOTAL
                Energy: 2mc2 = 1022 keV
                Charge: 0
                Momentum: 0
Positron decay makes
        back-to-back photons
                                                       1 keV
                                                  = 51             11
                                                hν              +5
               1k
                 eV
                                –           g y: : 0
                                          er ge         h/λ
                                                              =
            51                          En ar        m:
      : hν
          =               511              h entu
    gy : 0
  er ge            λ=
                        -           +    C m
                                           Mo
 n r
E a            : h/
 Ch men    tum
   Mo                                             TOTAL
                                        Energy: 2mc2 = 1022 keV
                                        Charge: 0
                                        Momentum: 0
Authors: TILLEY, WELLER, CHEVES, CHASTELER Citation: Nuclear Physics A595, 1 (1995)

Parent Parent Parent             Parent                      GS-GS Q-value Daughter
                                  T1/2        Decay Mode
Nucleus E(level) J!                                              (keV)     Nucleus
                                                                                       Decay
  18                                                                          18      Scheme
   9
     F       0        1+      109.77 m 5       " + : 100 %       1655.50 63
                                                                               8
                                                                                 O



Beta+:

 Energy      End-point energy          Intensity      Dose
  (keV)           (keV)                   (%)      ( MeV/Bq-s )

  249.8 3     633.5 6                  96.73 % 4      0.2416 3



Mean beta+ energy: 249.8 keV 3, total beta+ intensity: 96.73 % 4, mean beta+ dose: 0.2416 MeV/Bq-s 3

Electrons:

     Energy                Intensity         Dose
      (keV)                   (%)         ( MeV/Bq-s )

Auger K       0.52         3.072 % 11      1.597E-5 6



Gamma and X-ray radiation:

     Energy             Intensity           Dose
      (keV)                (%)           ( MeV/Bq-s )

XR k#2        0.525        0.009 % 3      4.5E-8 18
XR k#1        0.525        0.017 % 7      9E-8 4
Annihil.     511.0      193.46 % 8
Positron decay requires enough initial
      energy to make a positron

   p + e– n + ν           p   n + e+ + ν
mp+me+Q = mn+Eout      mp+Q = mn+me+Eout
                n      ν




               p+       β-
Parent Parent Parent           Parent                     GS-GS Q-value Daughter
                                T1/2       Decay Mode
Nucleus E(level) J!                                           (keV)     Nucleus
                                                                                    Decay
 57                                                                       57       Scheme
    Co       0.0      7/2-   271.74 d 6      ": 100 %         836.0 4        Fe
 27                                                                       26


Electrons:

         Energy                Intensity         Dose
          (keV)                   (%)         ( MeV/Bq-s )

Auger L        0.67           251 % 4          0.001684 24
Auger K        5.62           105.1 % 17       0.00591 10
CE K           7.3009 11       71.1 % 24       0.00519 18
CE L          13.5668 7        7.4 % 3         1.00E-3 3
CE K         114.9487 9        1.83 % 10       0.00211 12
CE L         121.2146 4        0.192 % 17      2.32E-4 21
CE K         129.3616 9        1.30 % 14       0.00169 18



Gamma and X-ray radiation:

          Energy                 Intensity         Dose
           (keV)                    (%)         ( MeV/Bq-s )

XR l          0.7                1.52 % 15       1.06E-5 11
XR k#2        6.391             16.6 % 9         0.00106 5
XR k#1        6.404             32.9 % 15        0.00211 10
XR k$1        7.058              3.91 % 19       2.76E-4 13
XR k$3        7.058              2.00 % 10       1.41E-4 7
             14.4129 6           9.16 % 15       0.001320 22
             122.06065 12       85.60 % 17       0.10448 21
             136.47356 29       10.68 % 8        0.01458 11
             230.4 4             4E-4 % 4        9E-7 9
             339.69 21           0.0037 % 3      1.26E-5 10
             352.33 21           0.0030 % 3      1.06E-5 11
Alpha decay when nucleus is too large
Alpha particles emitted at specific energies
Not dangerous from outside: can’t penetrate
skin
Dangerous when ingested/inhaled




Beta decay: neutron turned into proton or
proton turned into neutron
Neutrino takes some energy: beta particle
has range of energies
Positron decay makes annihilation photons
Electron capture: nucleus grabs low-lying
electron



Gamma decay comes when nucleus falls
from high energy state to low energy state
Gamma rays can be absorbed by electrons
in the atom
Conversion electron: Gamma ray ejects
electron
k-α, L-β X-ray radiation when electrons
from high shells fall to low shells
Auger electrons when k-α absorbed by
outer electrons, ejecting them.
Alpha decay when nucleus is too large
Alpha particles emitted at specific energies
Not dangerous from outside: can’t penetrate
skin
Dangerous when ingested/inhaled




Beta decay: neutron turned into proton or
proton turned into neutron
Neutrino takes some energy: beta particle
has range of energies
Positron decay makes annihilation photons
Electron capture: nucleus grabs low-lying
electron



Gamma decay comes when nucleus falls
from high energy state to low energy state
Gamma rays can be absorbed by electrons
in the atom
Conversion electron: Gamma ray ejects
electron
k-α, L-β X-ray radiation when electrons
from high shells fall to low shells
Auger electrons when k-α absorbed by
outer electrons, ejecting them.
Types of radioactive decay
Types of radioactive decay
Types of radioactive decay
Types of radioactive decay
Types of radioactive decay

Types of radioactive decay

  • 1.
  • 3.
    b ig T oo ns o to pr a ny ns m tro Too n eu a ny m T oo
  • 9.
    Dataset #2: Authors: J.K. TULI, G. REED, B. SINGH Citation: Nuclear Data Sheets 93, 1 (2001) Parent Parent Parent Parent GS-GS Q-value Daughter Decay Mode Nucleus E(level) J" T 1/2 (keV) Nucleus Decay Scheme 99 99 Tc 14 2 . 6 8 3 2 1 1 1/2- 6.015 h 9 I T : 9 9 . 9 9 63 6 % Tc 43 43 Electrons: Energy Intensity Dose (keV) (%) ( MeV/Bq-s ) CE M 1.6286 11 74.595 % 0.0012149 Auger L 2.17 10.32 % 6 2 . 2 4 0 E - 4 14 Auger K 15.5 2.05 % 4 3.17E-4 6 CE K 119.4670 12 8.84 % 0.01056 CE K 121.59 3 0.55 % 5 6.7E-4 6 CE L 137.4685 11 1.07 % 0.00147 CE L 139.59 3 0.172 % 16 2.40E-4 23 CE M 139.9670 14 0.194 % 2.72E-4 CE NP 140.4430 22 0.0374 % 5.25310E-5 CE M 142.09 3 0.034 % 3 4.8E-5 5 CE NP 142.56 3 0.0066 % 6 9.4E-6 9 Gamma and X-ray radiation: Energy Intensity Dose (keV) (%) ( MeV/Bq-s ) 2.1726 4 6.201E-9 % 1.347E-13 XR l 2.42 0.447 % 11 1.08E-5 3 X R k #2 18.251 2.14 % 6 3.91E-4 11 X R k #1 18.367 4.07 % 12 7.47E-4 21 X R k !3 20.599 0.330 % 10 6.79E-5 20 X R k !1 20.619 0.639 % 18 1.32E-4 4 X R k !2 21.005 0.145 % 4 3.04E-5 8 140.511 1 89.06 % 0.1251 142.63 3 0.0187 % 18 2.7E-5 3
  • 10.
    A conversion electronis ejected by a gamma photon from the nucleus
  • 11.
    A conversion electronis ejected by a gamma photon from the nucleus
  • 12.
    A kα X-raycomes when an electron from the L shell falls to the K shell
  • 13.
    A kα X-raycomes when an electron from the L shell falls to the K shell
  • 14.
    An Auger electronis ejected by a kα X-ray
  • 15.
    An Auger electronis ejected by a kα X-ray
  • 16.
    Gamma decay comeswhen nucleus falls from high energy state to low energy state Gamma rays can be absorbed by electrons in the atom Conversion electron: Gamma ray ejects electron k-α, L-β X-ray radiation when electrons from high shells fall to low shells Auger electrons when k-α absorbed by outer electrons, ejecting them.
  • 17.
    Gamma decay comeswhen nucleus falls from high energy state to low energy state Gamma rays can be absorbed by electrons in the atom Conversion electron: Gamma ray ejects electron k-α, L-β X-ray radiation when electrons from high shells fall to low shells Auger electrons when k-α absorbed by outer electrons, ejecting them.
  • 19.
  • 20.
    MP (MD MHe ) 11-34 c2 Note that the mass of the two electrons in the He atom compensates for the fact that the daughter atom has two fewer electrons than the parent atom. Applying this to the example given in Equation 11-33, the mass of the 232Th atom is 232.038124 u The mass of the daughter atom 228Ra is 228.031139 u, and adding it to the 4.002603 u mass of 4He, we get 232.033742 u for the total mass of the decay products Equation 11-34 then yields Q/c 2 0.004382 u, which, when multiplied by the con- version factor 931.5 MeV/c 2, gives Q 4.08 MeV. Thus, the rest energy of 232Th is greater than that of 228Ra 4He; therefore, 232Th is unstable toward spontaneous decay. The kinetic energy of the particle (for decays to the ground state of the daugh- ter nucleus) is slightly less than the decay energy Q because of the small recoil energy of the daughter nucleus. If the parent nucleus is at rest when it decays, the daughter 1600 !286 Number of particles 1200 !61 !0 800 !334 !330 400 ! !376 342 !247 !174 !80 !350 !30 !280 !235 !124 5.70 5.80 5.90 6.00 Energy, MeV
  • 23.
    Alpha decay whennucleus is too large Alpha particles emitted at specific energies Not dangerous from outside: can’t penetrate skin Dangerous when ingested/inhaled Gamma decay comes when nucleus falls from high energy state to low energy state Gamma rays can be absorbed by electrons in the atom Conversion electron: Gamma ray ejects electron k-α, L-β X-ray radiation when electrons from high shells fall to low shells Auger electrons when k-α absorbed by outer electrons, ejecting them.
  • 24.
    Alpha decay whennucleus is too large Alpha particles emitted at specific energies Not dangerous from outside: can’t penetrate skin Dangerous when ingested/inhaled Gamma decay comes when nucleus falls from high energy state to low energy state Gamma rays can be absorbed by electrons in the atom Conversion electron: Gamma ray ejects electron k-α, L-β X-ray radiation when electrons from high shells fall to low shells Auger electrons when k-α absorbed by outer electrons, ejecting them.
  • 26.
    _ n p + e– + ν p n + e+ + ν p + e– n+ ν n ν p+ β-
  • 30.
    Dataset #3: Author: E.BROWNE Citation: Nuclear Data Sheets 82, 379 (1997) Parent Parent Parent Parent GS-GS Q-value Daughter Decay Mode Nucleus E(level) J! T1/2 (keV) Nucleus Decay 90 90 Scheme 39 Y 0 2- 64.00 h 21 "- : 100 % 2280.1 16 40 Zr Beta-: Energy End-point energy Intensity Dose (keV) (keV) (%) ( MeV/Bq-s ) 25.0 7 93.8 16 1.4E-6 % 3 3.5E-10 8 185.6 10 519.4 16 0.0115 % 14 2.1E-5 3 933.7 12 2280.1 16 99.9885 % 14 0.9336 12 Mean beta- energy: 933.6 keV 12, total beta- intensity: 100.0000 % 20, mean beta- dose: 0.9336 MeV/Bq-s 12
  • 34.
  • 37.
    n udd νe e+ W+ u du p
  • 38.
    Positron decay makes back-to-backphotons – + TOTAL Energy: 2mc2 = 1022 keV Charge: 0 Momentum: 0
  • 39.
    Positron decay makes back-to-back photons 1 keV = 51 11 hν +5 1k eV – g y: : 0 er ge h/λ = 51 En ar m: : hν = 511 h entu gy : 0 er ge λ= - + C m Mo n r E a : h/ Ch men tum Mo TOTAL Energy: 2mc2 = 1022 keV Charge: 0 Momentum: 0
  • 42.
    Authors: TILLEY, WELLER,CHEVES, CHASTELER Citation: Nuclear Physics A595, 1 (1995) Parent Parent Parent Parent GS-GS Q-value Daughter T1/2 Decay Mode Nucleus E(level) J! (keV) Nucleus Decay 18 18 Scheme 9 F 0 1+ 109.77 m 5 " + : 100 % 1655.50 63 8 O Beta+: Energy End-point energy Intensity Dose (keV) (keV) (%) ( MeV/Bq-s ) 249.8 3 633.5 6 96.73 % 4 0.2416 3 Mean beta+ energy: 249.8 keV 3, total beta+ intensity: 96.73 % 4, mean beta+ dose: 0.2416 MeV/Bq-s 3 Electrons: Energy Intensity Dose (keV) (%) ( MeV/Bq-s ) Auger K 0.52 3.072 % 11 1.597E-5 6 Gamma and X-ray radiation: Energy Intensity Dose (keV) (%) ( MeV/Bq-s ) XR k#2 0.525 0.009 % 3 4.5E-8 18 XR k#1 0.525 0.017 % 7 9E-8 4 Annihil. 511.0 193.46 % 8
  • 43.
    Positron decay requiresenough initial energy to make a positron p + e– n + ν p n + e+ + ν mp+me+Q = mn+Eout mp+Q = mn+me+Eout n ν p+ β-
  • 46.
    Parent Parent Parent Parent GS-GS Q-value Daughter T1/2 Decay Mode Nucleus E(level) J! (keV) Nucleus Decay 57 57 Scheme Co 0.0 7/2- 271.74 d 6 ": 100 % 836.0 4 Fe 27 26 Electrons: Energy Intensity Dose (keV) (%) ( MeV/Bq-s ) Auger L 0.67 251 % 4 0.001684 24 Auger K 5.62 105.1 % 17 0.00591 10 CE K 7.3009 11 71.1 % 24 0.00519 18 CE L 13.5668 7 7.4 % 3 1.00E-3 3 CE K 114.9487 9 1.83 % 10 0.00211 12 CE L 121.2146 4 0.192 % 17 2.32E-4 21 CE K 129.3616 9 1.30 % 14 0.00169 18 Gamma and X-ray radiation: Energy Intensity Dose (keV) (%) ( MeV/Bq-s ) XR l 0.7 1.52 % 15 1.06E-5 11 XR k#2 6.391 16.6 % 9 0.00106 5 XR k#1 6.404 32.9 % 15 0.00211 10 XR k$1 7.058 3.91 % 19 2.76E-4 13 XR k$3 7.058 2.00 % 10 1.41E-4 7 14.4129 6 9.16 % 15 0.001320 22 122.06065 12 85.60 % 17 0.10448 21 136.47356 29 10.68 % 8 0.01458 11 230.4 4 4E-4 % 4 9E-7 9 339.69 21 0.0037 % 3 1.26E-5 10 352.33 21 0.0030 % 3 1.06E-5 11
  • 47.
    Alpha decay whennucleus is too large Alpha particles emitted at specific energies Not dangerous from outside: can’t penetrate skin Dangerous when ingested/inhaled Beta decay: neutron turned into proton or proton turned into neutron Neutrino takes some energy: beta particle has range of energies Positron decay makes annihilation photons Electron capture: nucleus grabs low-lying electron Gamma decay comes when nucleus falls from high energy state to low energy state Gamma rays can be absorbed by electrons in the atom Conversion electron: Gamma ray ejects electron k-α, L-β X-ray radiation when electrons from high shells fall to low shells Auger electrons when k-α absorbed by outer electrons, ejecting them.
  • 48.
    Alpha decay whennucleus is too large Alpha particles emitted at specific energies Not dangerous from outside: can’t penetrate skin Dangerous when ingested/inhaled Beta decay: neutron turned into proton or proton turned into neutron Neutrino takes some energy: beta particle has range of energies Positron decay makes annihilation photons Electron capture: nucleus grabs low-lying electron Gamma decay comes when nucleus falls from high energy state to low energy state Gamma rays can be absorbed by electrons in the atom Conversion electron: Gamma ray ejects electron k-α, L-β X-ray radiation when electrons from high shells fall to low shells Auger electrons when k-α absorbed by outer electrons, ejecting them.