Decay Schemes - NucleonicaWiki -...

From NucleonicaWiki

In the following, the extracts from the Karlsruhe Nuclide Chart show both the parent and daughter. Adjacent tothe nuclide box extract, the decay scheme is shown giving more details of the decay processes. These decayschemes are an aid to understanding the contents of the nuclide chart boxes.

More diagrams can be found in the new brochure for the 8th Edition of the Karlsruhe Nuclide Chart which cannow be ordered (http://shop.marktdienste.de/shoppages/produktuebersicht.jsp) .

1 9 F 18 (Z=8, N=10)1.1 References

2 18 Ar 41 (Z=18, N=23)2.1 References

3 27 Co 57 (Z=27, N=30)3.1 References

4 27 Co 60 (Z=27, N=33)4.1 References

5 39 Y 90 (Z=39, N=51)5.1 Y 90m5.2 References5.3 Y 905.4 References

6 29 Cu 64 (Z=29, N=35)6.1 References

7 42 Mo 99 (Z=42, N=57)7.1 References

8 43 Tc 99 (Z=43, N=56)8.1 Tc 99m8.2 Tc 99

9 53 I 123 (Z=53, N=70)9.1 References

10 53 I 131 (Z=53, N=78)10.1 References

11 54 Xe 133 (Z=54, N=79)11.1 Xe 133m11.2 Xe 13311.3 References

12 55 Cs 137 (Z=55, N=82)12.1 References

13 62 Sm 153 (Z=62, N=91)

Decay Schemes - NucleonicaWiki http://www.nucleonica.net/wiki/index.php?title=Decay_Schemes#53_I_...

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13.1 References14 88 Ra 226 (Z=88, N=138)

14.1 References15 More Information

The nuclide F 18 is an isotope of the element flourine (atomic number 9, chemical symbol F). There are 18nucleons in the nucleus consisting of 9 protons and 9 neutrons. F 18 is radioactive with a half-life of 109.728minutes.

Main Radiations Branching E

0.9686 0.633 MeV

0.0314

The colour red indicates that the nucleus decays by electron capture / positron emission.

The symbol without the symbol in the box indicates that the main decay mode is by positron emission(branching ratio 96.86 %). The endpoint energy of the emitted positrons is 0.633 keV. The branching ratio for decay is 3.14%. There are no emissions observed.

The radionuclide F 18 is a widely used tracer in nuclear medicine. The F18-FDG tracer is produced from F 18isotopes and it behaves in the human metabolic system similar to normal glucose. The nuclide F 18 emitspositrons that anihilate with free electrons in the body. After anihilation the two oppositely moving 511 keVX-rays can be easily detected by co-incidence detectors placed around the body. The pairs of photons definestaight lines in the body volumen. The highest concentration of the tracer can be found where the lines cross.With this method all glucose consuming processes, e. g. in cancer cells, can be located.

F 18: Extract from the Karlsruhe Nuclide

Chart, 8th Edition (2012) F 18 Decay Scheme


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Half-life:

109.728(19) mM.-M. Bé et al. Table of radionuclides, vol.1, A=1 to 150Monographie BIPM-5 (2004)

Radiation:

ß+ 0.6335(6) MeV, 96.86(19) %, decay to the ground state O18EC 3.14(19) %, decay to the ground state O18no γhttp://www.tunl.duke.edu/nucldata/GroundStatedecays/18F.shtml

The nuclide Ar 41 is an isotope of the element argon (atomic number 18, chemical symbol Ar). There are 41nucleons in the nucleus consisting of 18 protons and 23 neutrons. Ar 41 is radioactive with a half-life of 1.83hours.


0.9916 1.198 MeV

0.9916 1294 keV

0.0079 2.492 MeV

Ar 41: Extract from the Karlsruhe Nuclide

Chart, 8th Edition (2012)Ar 41 Decay Scheme


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0.0005 0.815 MeV

0.0005 1677 keV

The colour blue indicates that the nucleus decays by emission. Ar 41 is characterised by the emission ofseveral particles with different endpoint energies. This implies that in addition to direct transition to theground state of the daughter nuclide K 41, transitions can also occur through the excited states of the daughternuclide.

In the case of decay, the nuclide box contains a maximum of two endpoint energies. The first number(1.2 MeV) corresponds to the strongest transition (highest emission probability) whereas the second correspondsto the highest endpoint energy (2.5 MeV). Additional transitions are indicated through the use of dots. Theexcited states of the daughter nuclide K 41 release their energy through gamma emission to the daughter groundstate. The decay process can be understood more clearly from the decay scheme. It can then be seen that gammaemission at 1294 keV is due to transitions from the excited level at 1.294 MeV to the ground state of K 41following the most probable emission of 1.198 MeV. A further weak transition from the excited level at1.677 MeV is indicated by dots in the nuclide box.

The last row 0.5 gives the (n, ) cross section for thermal neutrons in barns for the formation of Ar 42.

Half-life: 109.611(38) m --> 1.83 h, V.Chisté, M.M.Bé, Lab.Nat.Henri Becquerel,Recommended data Febr.2010, Nucl.Data Sheets 94(2001)429

β− 1.1983(11) MeV, 99.16(2) %, to 7/2- 1294 keV level of K41 2.4916(4) MeV, 0.79(2) %, to 3/2+ ground state of K41 0.8146(4) MeV, 0.052(5)%, to 7/2+ 1677 keV level of K41γ 1293.64(4) keV, 99.16(2) %, from 7/2- 1294 keV level to 3/2+ ground state K41 1677.0(3) keV, 0.0515(49) %, Nucl.Data Sheets 94(2001)429

σ: 0.5(1) b, S.Mughabghab, Atlas of Neutron Resonances, Resonance Parameters and Thermal Cross Sections Z=1-100, 5th Edition, Elsevier, Amsterdam (2006)

The nuclide Co 57 is an isotope of the element cobalt (atomic number 27, chemical symbol Co). There are 57nucleons in the nucleus consisting of 27 protons and 30 neutrons. Co 57 is radioactive with a half-life of 271.80days.


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0.998

0.856 122 keV

0.1068 136 keV

0.0916 14 keV

T= 8.56


In this case all nuclei decay by electron capture because the Q-value (Q = 0.836 MeV) is not high enough for decay (the threshold energy for positron emission is 1.022 MeV). The most probable transition of the Co 57nuclei is through capture to an excited state of Fe 57 at 0.136 MeV. From this level Co 57 continues to decayby internal transitions emitting either photons with energies 122 keV (85.6%) and 14 keV (9.16%) in cascade,or through the emission of 136 keV photons (10.68%) leading directly to the ground state of Fe 57. The symbol

e- indicates that the transition from the level at 14 keV is predominately via electron emission (the conversioncoefficient T is 8.56).

Additional electron capture processes (not shown), with lower branching ratios, give rise to excited states of Fe57 which then de-excite by photon emission to the ground state.

Half-life:

271.80(5) drecommended decay data from "update of X Ray and Gamma Ray Decay Data Standardsfor Detector Calibration and Other Applications", IAEA Vol.1 (2007)

Co 57: Extract from the Karlsruhe Nuclide

Chart Co 57 Decay Scheme


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Radiation:

EC 100 %γ 122.06065(12) keV, 85.51(6) % 136.47356(29) keV, 10.71(15) % 14.41295(31) keV, 9.15(17) % conversion electrons are present αT = 8.56%

...recommended decay data from "update of X Ray and Gamma Ray Decay Data Standardsfor Detector Calibration and Other Applications", IAEA Vol.1 (2007)Other gammas:Nuclear Data Sheets 85, 415 (1998)

The nuclide Co 60 is an isotope of the element cobalt (atomic number 27, chemical symbol Co). There are 60nucleons in the nucleus consisting of 27 protons and 33 neutrons. Co 60 is radioactive with a half-life of 5.2711years.


0.9988 0.318 MeV

0.9985 1173 keV

0.0012 1.492 MeV

0.9998 1332 keV

The colour blue indicates that the nucleus decays by emission. Co 60 is characterised by the emission ofseveral particles with different endpoint energies. This implies that transitions to the ground state of thedaughter nuclide Ni 60 can occur through different excited states of the daughter nuclide.

Co 60: Extract from the Karlsruhe Nuclide

Chart, 8th Edition (2012) Co 60 Decay Scheme


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In the case of decay, the nuclide box contains a maximum of two endpoint energies. The first number(0.3 MeV or 0.318 MeV on the Decay Scheme) corresponds to the strongest transition (highest emissionprobability) whereas the second corresponds to the highest endpoint energy (1.5 MeV or 1.492 MeV on theDecay Scheme). Additional transitions are indicated through the use of dots. The excited states of the daughternuclide Ni 60 release their energy through gamma emission to the daughter ground state. The decay process canbe understood more clearly from the decay scheme. It can then be seen that gamma emission at 1173 keV is dueto transitions from the excited level at 2.506 MeV to the level at 1.332 keV following the most probable emission of 0.318 MeV. Another gamma emission can be seen at 1332 keV due to transitions from the excitedlevel at 1.332 MeV to the ground state of Ni 60. Further emissions are indicated by dots in the nuclide box.

The last row 2.0 gives the (n, ) cross section for thermal neutrons in barns for the formation of Co 60.

Because the half-life of Co 60 isotope is longer than 5 years, Co 60 sources are used as calibration sources forgamma-detectors around the energy levels 1173 and 1332 keV, which are the main gamma energies of Co 61.

On the decay scheme the Co 60m metastable state of Co 60 is shown. It has 10.467 minutes half-life. Thetransition to the Co 60 ground state occurs primarily through electron capture ( T=48). Only 2.04% of

transitions occur via gamma emission with an energy of 59 keV.

Co 60m can also decay by emission (with an energy of 1.550 MeV) to an excited state of Ni 60. The smallbranching ratio is indicated by a small blue triangle in the bottom right corner of nuclide box. The excited statedecays further to the ground state through the emission of 1332 keV gamma photon.

The last row 58 gives the (n, ) cross section for thermal neutrons in barns for the formation of Co 61.

Half-life: 1925.23(27) d /365.2422 (d per mean solar year) = 5.2711(7) arecommended decay data from "update of X Ray and Gamma Ray Decay Data Standardsfor Detector Calibration and Other Applications", IAEA Vol.1 (2007)others:1925.20(25) d/365.2422 (d per mean solar year) = 5.2710(7) aM.P.Unterweger, Appl.Rad.Isot.56(2002)125 1925.28(14) d/365.2422 (d per mean solar year) = 5.2712(4) a, weighted averageNuclear Data Sheets 100(2003)347

Radiation:ß- 100 %γ 1332.492(4) keV, 99.9826(6) % 1173.228(3) keV, 99.85(3) %recommended decay data from "update of X Ray and Gamma Ray Decay Data Standardsfor Detector Calibration and Other Applications", IAEA Vol.1 (2007)ß- 0.31788(10) MeV, 99.88(3) % 1.492(20) MeV, 0.12(3) % ...Nuclear Data Sheets 100(2003)347

Cross section:σ 2.0(2) bS.Mughabghab, Atlas of Neutron Resonances, Resonance Parameters and


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Thermal Cross Sections Z=1-100, 5th Edition, Elsevier, Amsterdam (2006)

The nuclide Y 90 is an isotope of the element yttrium (atomic number 39, chemical symbol Y). There are 90nucleons in the nucleus consisting of 39 protons and 51 neutrons. Y 90 is radioactive and has two states shownin Karlsruhe Nuclide Chart (KNC) below: the ground state with a half-life of 64.042 hours and one isomericstate (Y 90m) with a half life of 3.19 hours.


0.91 480 keV

0.971 203 keV

Y 90m has two competing decay modes: internal transitions to ground state of Y 90 and to Zr 90. Thedominant (isomeric transition) decay mode is indicated by white.

The details of this process are shown in the decay scheme. The energy difference between Y 90m and Y 90states (Q=683 keV) results mainly in the emission of 480 keV and 203 keV photons in cascade. As analternative to gamma emission, the excited states can de-excite via internal conversion and the emission ofconversion electrons. The conversion factors are T = 0.0972 and T = 0.0272 for the 480 and 203 keV

Y 90: Extract from the Karlsruhe Nuclide

Chart, 8th Edition (2012)Y 90 and Y 90m Decay Scheme


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energies respectively.

An additional weak transition directly to the ground state of Y-90 (via gamma emission and internal conversion)has also been observed. This is indicated by the points (...) after the energies in the box or dashed lines ondecay scheme.

Y 90m also decays to Zr 90 through decay - albeit with a very small branching ratio (approx. 0.0019%). Thisis indicated by the small blue triangle in the box. Points following the ... indicates that the branching ratio forthis decay type is smaller than 1%. The beta decay is followed by the emission of a 2319 keV photon.

Half-life:

3.19 (6) hLaboratoire National Henri Becquerel: Recomended Datahttp://www.nucleide.org/DDEP_WG/Nuclides/Y-90m_tables.pdf

Radiation:

IT= 99.9981%ß-=0.0019%ß energies (MeV)0.6429 0.0019%...Gammas (I , keV) 202.53 97.1%479.51 90.97%...

Gammas (ß-, keV)2318.99 0.0019 %Laboratoire National Henri Becquerel: Recomended Datahttp://www.nucleide.org/DDEP_WG/Nuclides/Y-90m_tables.pdf


0.99983 2.280 MeV

1.4e-8 2186 keV

The colour blue indicates that Y 90 decays by decay. The main decay process is through the emission of abeta particle with a branching ratio of 99.983% and an end-point energy of 2.280 MeV. Y 90 is a high energy emitter with a very low rate of emission. Additional lower energy betas and associated gammas are alsoobserved (photons with energy 2186 keV are shown in the box and on the scheme). These additional radiationsare indicated by points in the box and dashed lines on the scheme.

The last row in box < 6.5 gives the (n, ) cross section for thermal neutrons in barns for the formation of Y 91.


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Y 90 has a major application in cancer therapy where pure radiation is required. particles havesignificantly smaller ranges but higher cell destruction probabilities in the body than photons hence they canbe applied locally for intensive cell destruction.

Half-life:

2.6684 (13) d = 64.0416 (312) hLaboratoire National Henri Becquerel: Recomended Datahttp://www.nucleide.org/DDEP_WG/Nuclides/Y-90_tables.pdf

Q value:

2.2798 MeVLaboratoire National Henri Becquerel: Recomended Datahttp://www.nucleide.org/DDEP_WG/Nuclides/Y-90_tables.pdf

Radiation:

ß-= 100 %ß energies (MeV)2.2798 99.983%...Gammas (keV)2186.254 1.4 e-6 %...Laboratoire National Henri Becquerel: Recomended Datahttp://www.nucleide.org/DDEP_WG/Nuclides/Y-90_tables.pdf

Cross section:σ < 6.5 bS.Mughabghab, Atlas of Neutron Resonances, Resonance Parameters andThermal Cross Sections Z=1-100, 5th Edition, Elsevier, Amsterdam (2006)

The nuclide Cu 64 is an isotope of the element copper (atomic number 29, chemical symbol Cu). There are 64nucleons in the nucleus consisting of 29 protons and 35 neutrons. Cu 64 is radioactive with a half-life of12.7004 hours.


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0.4352

0.3848 0.579 MeV

0.1752 0.653 MeV

0.0047

0.0047 1346 keV

The colours red and blue indicate that the nucleus decays both by electron capture / positron emission and by emission. The fact that the coloured triangles are large indicates that the branching ratios of / and emission are > 5%.

The arrangement of the symbols i.e. , , in the box indicates that the main decay mode is by electroncapture. The second most important decay mode is through the emission of a with an endpoint energy of0.579 MeV. Positron emission is also observed to a lesser extent with the emission of a 0.653 MeV positron.These emissions can be more clearly seen in the decay scheme. Weak gamma emission (emission probabilityless than 1%) at 1346 keV is indicated through the use of brackets around the energy value.

Cu 64 has a neutron capture cross section of about 270 barns for the formation of Cu 65 by thermal neutrons.

Half-life: 12.7004(20) h, M.M.Bé, R.G.Helmer, Lab.Nat.Henri Becquerel,Recommended Data, July 2011

Radiation:ε 43.53(20) % to 0+ ground state of Ni64 0.4744(33) % to 2+ 1346 keV level of Ni64β− 0.5794(7) MeV, 38.48(26) %, to 0+ ground state of Zn64β+ 0.6531(2) MeV, 17.52(15) %, to 0+ ground state of Ni64 γ 1345.77(6) keV, 0.4748(34) %, from 2+ 1346 kev level to 0+ ground state Ni 64 M.M.Bé, R.G.Helmer, Lab.Nat.Henri Becquerel,Recommended Data,July 2011

Cu 64: Extract from the Karlsruhe Nuclide

Chart, 8th Edition (2012)

Cu 64 Decay Scheme


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σ:~ 270(170) b, N.E.Holden, Neutron Scattering and Absorption Properties (Revised 2003), Handbook of Chemistry and Physics on CD-ROM, Version 2006, 11-185

The nuclide Mo 99 is an isotope of the element molybdenum (atomic number 42, chemical symbol Mo). Thereare 99 nucleons in the nucleus consisting of 42 protons and 57 neutrons. Mo 99 is radioactive with a half-life of65.976 hours.


0.822 1.214 MeV

0.123 740 keV

0.0614 181 keV

0.0430 778 keV

The colour blue indicates that the nucleus decays by emission. The fact that Mo 99 decays to Tc 99mmetastable- but also to Tc 99 ground states is indicated by the letters "m" and "g" in nuclide box of Mo 99.Because the branching ratio to Tc 99m decay is higher than the branching ratio to Tc 99 decay the letter "m" ispreceding the letter "g". Mo 99 is characterized by the emission of several particles with different endpointenergies. The particle at 1.214 MeV energy has the highest endpoint energy and highest branching ratio of82.2%. This transition leads to Tc 99m directly. Tc 99m has a half-life of 6.007 hours and decays by isomerictransition through the emission of conversion electrons and gammas to Tc 99 (for the details see the decayscheme of Tc 99m).

Additional transitions of Mo 99 are indicated through the use of dots and they lead to different excited statesof Tc 99. The excited states of Tc 99 release their energies through different gamma emissions. The decayprocess can be understood more clearly from the decay scheme. It can then be seen that the 720 keV gamma

Mo 99: Extract from the Karlsruhe Nuclide

Chart, 8th Edition (2012)Mo 99 Decay Scheme


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emission with an emission probability of 12.3% is due to transitions from the excited level at 0.921 MeV to thelevel at 0.181 MeV. The gamma emissions at 181 keV with an emission probability of 6.14% is due to transitionsfrom excited level at 0.181 MeV to ground state. The third most probable 778 keV gamma emission isassociated with the excited level at 0.921 MeV leading to Tc 99m. Further weak transition are indicated by dotsin the nuclide box of Mo 99.

The Tc 99m is a widely used tracer in nuclear medicine. Its short half-life of 6 hours does not allowlong-distance transport. The "moly cow" is a Tc 99m generator that is used to produce Tc 99m as a decayproduct of Mo 99 (half-life 66 hours).

Half-life:

65.976(24) h = 2.7490(10) dNucl.Data Sheets 112(2011)275, adopted by M.J.Woods et al.,Appl.Rad Isot.60(2004)257others:65.974(14) h = 2.7489(6) dH.Schrader,Appl.Rad.Isot.60(2004)317

Radiation:

ß- 1.214(1) MeV, 84 % ... γ 739.500(17) keV, 100(1) % rel.intensity 181.068(8) keV, 50.1(7)% " " 777.921(20) keV, 35.1(4)% " " ...for absolute intensity multiply by 0.1226(18)m,gNucl.Data Sheets 112(2011)275

The nuclide Tc 99 is an isotope of the element technetium (atomic number 43, chemical symbol Tc). There are99 nucleons in the nucleus consisting of 43 protons and 56 neutrons. The metastable state Tc 99m is radioactive

with a half-life of 6.007 h. The ground state is radioactive with a half-life of 2.1x105 y.


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Main Radiations Branching E(keV)

0.89 141

The white indicates that the isomer state decays mainly by the emission of a gamma photon. Because I is theleading entry, the branching ratio for this mode is > 50% but < 95%. The metastable state at 143 keV decaysinitially to the 2 keV deeper-lying level at 141 keV. This transition has such a high conversion coefficient that

effectively only conversion electrons are emitted. This is indicated by specifying e−. The most importanttransition is from the 141 keV to the ground state by the emission of a 141 keV gamma photon.

The small blue triangle indicates decay by emission with an emission probability less then 5%. Additionalbeta particles with branching ratios less than 1% are also emitted as indicated by the dots. Associated with the

emission is also a weak gamma emission indicated by the brackets and dots.

Tc 99m is the most used tracer nuclide in nuclear medicine. It is produced through the decay of Mo 99 (so calledMo 99 "cow"). Mo 99 has a half-life of 66 hours and can be easily transported to hospitals where its decayproduct Tc 99m with a half-life of only 6 hours is inconvenient for transport.

References

Half-life: 6.0067(5) h, Nucl.Data Sheets 112(2011)275, evaluated and recommendedby M.J.Woods et al., Appl.Rad.Isot.60(2004)257

Radiation:Iγ 99.9963(6) %ß- 0.0037(6) %Iγ 140.511(2) keV, 89(3) % ..., e-ß- 0.3467(20) MeV, 0.0026(5) % ...

Tc 99: Extract from the Karlsruhe Nuclide

Chart, 8th Edition (2012)Tc 99 Decay Scheme


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γ 322.4(2) keV, 2.62(14) % rel.int....for absolute intensity multiply by 3.7E-5 Nucl. Data Sheets 112(2011)275

Main Radiations Branching E(keV)

0.99998 294

The colour blue indicates that the nucleus decays by emission. Tc 99 is characterised by the emission ofseveral particles with different endpoint energies. The most probable and highest energy emission is at294 keV. Additional beta particles are also emitted as indicated by the dots. A weak (branching ratio 0.0008%)gamma emission at 90 keV is also observed

Neutron capture in Tc 99 leads to the formation of Tc 100 with a cross section of 22.8 barns.

References

Half-life: 2.111(12)E5 a, Nucl. Data Sheets 112(2011)275, adopted by B.M.Courseyet al., Int.J.Appl.Rad Isot.60(2004)257

Radiation:ß- 0.2935(14) MeV, 99.9984(4) % ...γ 89.5(2) keV, 6.5(15)E-6%, α(tot) 1.50, e- Nucl.Data Sheets 112(2011)275

Cross Section: σ 22.8(13) bS.F.Mughabghab, Atlas of Neutron Resonances, Resonance Parameters andThermal Cross Sections Z = 1-100, 5th Ed. Elsevier, 2006

The nuclide I 123 is an isotope of the element iodine (atomic number 53, chemical symbol I). There are 123nucleons in the nucleus consisting of 53 protons and 70 neutrons. I 123 is radioactive with a half-life of 13.224hours.


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1.00

0.833 159 keV


The arrangement of the symbols i.e. and "no " in the box indicates that the only observed decay mode is byelectron capture. The electron capture transition energy is dissipated through the emission of a 1.070 MeVmono-energetic neutrino with emission probability 97%. The resulting excited state of Te 123 de-excites throughthe emission of 159 keV gamma photon with an emission probability 83.3%. The difference betweenprobabilities of the main electron capture and the associated gamma emission can be explained throughconversion electrons. These are not indicated in the nuclide box because the total conversion coefficient

T=0.1902 is smaller than 1. I 123 decays only to the ground state of Te 123. This is indicated by the letter "g" in

the I 123 nuclide box. The Te 123m metastable state at the level of 0.248 MeV is not in the decay path of I 123nuclide. It is indicated to explain the electron capture and the 159 keV gamma photons showed in the box of Te123m. The gamma decay of Te 123m results in Te 123.

The radionuclide I 123 is produced in cyclotrons through the interaction of protons on xenon. It is used innuclear medicine for diagnostic purposes.

Half-life:

13.224(2) hrecommended decay data from "update of X Ray and Gamma Ray Decay Data Standardsfor Detector Calibration and Other Applications", IAEA Vol.1 (2007)others:13.2235(19) hM.P.Unterweger, Appl.Rad.Isot.56(2002)125Nucl.Data Sheets 102(2004)547

I 123: Extract from the Karlsruhe Nuclide

Chart, 8th Edition (2012)I 123 Decay Scheme


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Radiation:

EC 100 % γ 158.97(5) keV, 83.25(21) % ...recommended decay data from "update of X Ray and Gamma Ray Decay Data Standardsfor Detector Calibration and Other Applications", IAEA Vol.1 (2007)

The nuclide I 131 is an isotope of the element iodine (atomic number 53, chemical symbol I). There are 131nucleons in the nucleus consisting of 53 protons and 78 neutrons. I131 is radioactive with a half-life of 8.0228 d.


0.896 0.606 MeV

0.815 367 keV

0.0039 0.807 MeV

0.00021 164 keV

0.0723 0.334 MeV

0.0716 637 keV

The colour blue indicates that the nucleus decays by emission. I 131 is characterised by the emission ofseveral particles with different endpoint energies. A direct transition to the ground state of the daughternuclide Xe 131 has not been observed. Transitions occur through the excited states of the daughter nuclide andwith a very small (0.39%) probability through the metastable Xe 131m that has a half life of 11.9 d.

In the case of decay, the nuclide box contains maximum two endpoint energies. The first number (0.606MeV) corresponds to the strongest transition (highest emission probability) whereas the second corresponds to

I 131: Extract from the Karlsruhe Nuclide

Chart, 8th Edition (2012)I 131 Decay Scheme


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the highest endpoint energy (0.807 MeV). Additional transitions are indicated through the use of dots.The excited states of the daughter nuclide Xe 131 release their energy through gamma emission to the daughterground state. On the decay scheme can be seen that the most important (0.606 MeV) emmision is followedby two different gamma emission at level 364 keV. One with 364 keV and one with 284 keV. One other way oftransitions is emitting a particle with an energy of 0.334 MeV that follows a gamma emission with an energyof 637 keV. Further weak transitions are indicated by dots in the nuclide box.

Neutron capture in I 131 leads to the formation of I 132 with a cross section of 0.7 barns.

With a very small probability (0.39%) the I 131 nucleus emits also particles with an energy of 0.807 MeV.This is the maximum endpoint energy of this decay. This emission results a Xe 131m metastable nuclide witha half life of 11.9 d. This metasable state has energy difference to ground state of 164 keV. The transition to theground state is mostly due to conversion electrons.

Half-life:

8.0228(24) drecommended decay data from "update of X Ray and Gamma Ray Decay Data Standardsfor Detector Calibration and Other Applications", IAEA Vol.1 (2007)others:8.0252(6) dNuclear Data Sheets 107(2006)2715

Radiation:

ß- 0.6063(6) MeV, 89.6(8) % 0.8069(6) MeV,0.39(9) % ...Nuclear Data Sheets 107(2006)2715 γ 364.489(5) keV, 81.2(8) % 636.989(4) keV, 7.26(8) % 284.305(5) keV, 6.06(6) % ...decay to Xe 131grecommended decay data from "update of X Ray and Gamma Ray Decay Data Standardsfor Detector Calibration and Other Applications", IAEA Vol.1 (2007)

Cross Section:

σ 22.8(13) bS.F.Mughabghab, Atlas of Neutron Resonances, Resonance Parameters andThermal Cross Sections Z = 1-100, 5th Ed. Elsevier, 2006

The nuclide Xe 133 is an isotope of the element xenon (atomic number 54, chemical symbol Xe). There are 133nucleons in the nucleus consisting of 54 protons and 79 neutrons. Xe 133 ground state is radioactive with ahalf-life of 5.2475 days. Xe 133 has an isomeric state with a half-life of 2.198 days.


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0.1012 233 keV

Xe 133m is the isomeric state of Xe 133. The white colour indicates that it decays by isomeric transition to Xe133 ground state. The transition predominately occur via electron emission with a conversion factor T=8.88. It

is indicated by e- in the box. I in the box indicates that by this isomeric transition gamma emission alsoobserved taht has 233 keV energy. The emission probaility is of these gammas is 10.12%.


0.985 0.346 MeV

0.369 80 keV

The blue colour indicates that Xe 133 ground state decays by emission to stable Cs 133 isotope. The mainbranch is the 0.346 MeV beta emission with 98.5% emission probability. It is followed by electron and gammaemission. The electron conversion factor is: T=1.073, the emision probability of 81 keV gamma photons is:

36.9%. Other weak branches are shown in the box by points (…) and on the decay scheme by dashed lines.

The last row in the box 190 gives the (n, ) cross section for thermal neutrons in barns for the formation of Xe154.

The Xe 133 gas is used in nuclear medicine. It is suitable in pulmonary ventilation studies. It also can be appliedto cerebral blood flow assessment.

Xe 133: Extract from the Karlsruhe Nuclide

Chart Xe 133 Decay Scheme


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Half-life:

5.2475 (5) d Nuclear Data SheetsVolume 112, Issue 4, April 2011, Pages 855-1113 http://www.sciencedirect.com/science/article/pii/S0090375211000202

Radiation:

ß- = 100 %ß- 0.346(3) MeV, 98.5(13) % ...γ 80.9979(11) keV, 36.9(3) %, α(tot) 1.703, e- ...Nuclear Data SheetsVolume 112, Issue 4, April 2011, Pages 855-1113 http://www.sciencedirect.com/science/article/pii/S0090375211000202

σ:

σ 190(90) bN.E.Holden, Neutron Scattering and Absorption Properties (Revised 2003),Handbook of Chemistry and Physics on CD-ROM, Version 2006, 11-185

The nuclide Cs 137 is an isotope of the element caesium (atomic number 55, chemical symbol Cs). There are137 nucleons in the nucleus consisting of 55 protons and 82 neutrons. Cs 137 is radioactive with a half-life of30.08 years.


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0.947 0.514 MeV

0.851 662 keV

0.053 1.176 MeV

0.0006 0.892 MeV

0.0006 284 keV

The colour blue indicates that the nucleus decays by emission. Cs 137 is characterised by the emission ofseveral particles with different endpoint energies. The most probable − emission is at 0.5 MeV whereas thehighest energy emission occurs at 1.2 MeV. Additional beta particles are also emitted indicated by the dots. Thebox entry m indicates that the main − decay is to the metastable state (94.7%) Ba 137m.

The gamma transition from this metastable state is found in the nuclide box Ba 137m. The use of the symbol gindicates that the direct transition to the ground state has a branching greater than 5%. Actually in this case it is5.3%. Decay to an excited state of the daughter Ba 137 is less probable (less than 1%) and gives rise to the weakgamma emission at 284 keV indicated by the entry (284).

Neutron capture in Cs 137 leads to the formation of Cs 138m with a cross section of 0.20 barns, and to Cs 138gwith a cross section of 0.07 barns

Half-life: 30.08(9) a, Nucl.Data Sheets 108(2007)2173

β− 0.51403(23) MeV, 94.7(2) %, to 11/2- 662 keV level of Ba137m 1.176(1) MeV, 5.3(2) %, to 3/2+ ground state of Ba137 0.89213(20) MeV, 0.00058(8)%, to 284 keV level of Ba137g

m,g

Cs 137: Extract from the Karlsruhe Nuclide Chart,

8th Edition (2012)Cs137 Decay Scheme


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γ 283.5(1) keV, 0.00058(8) %, from 284 keV level to 3/2+ ground state Ba137,Nucl.Data Sheets 108(2007)2173

σ: 0.20 + 0.07 b, N.E.Holden, Neutron Scattering and Absorption Properties (Revised 2003), Handbook of Chemistry and Physics on CD-ROM, Version 2006, 11-185

The nuclide Sm 153 is an isotope of the element samarium (atomic number 62, chemical symbol Sm). There are153 nucleons in the nucleus consisting of 62 protons and 91 neutrons. Sm 153 is radioactive with a half-life of46.284 hours.


0.494 0.704 MeV

0.292 103 keV

0.0473 70 keV

0.184 0.807 MeV

The colour blue indicates that Sm 153 decays by - emission. Three main branches and more than 10 otherweak beta transitions can be observed in this decay process. On the simplified decay scheme is shown that themost intensive beta emission has 0.704 MeV endpoint energy with 49.4% emission probability. This is followedby 103 keV gamma emission or emitting conversion electrons. The highest endpoint energy of beta emission is0.807 MeV with 18.4% emission probability. The second probable beta emission has 0.634 MeV endpointenergy (not shown in the box). It leads to an excited state at the level 173 keV. To de-excite this state there are

Sm 153: Extract from the Karlsruhe Nuclide

Chart Sm 153 Decay Scheme


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two transitions in cascade observed: at the level 173 keV is a gamma emission with 70 keV energy or electronemission and at the level 103 keV is a gamma emission with 103 keV energy or electron emission. The 70 keVgamma emission has a probability 4.73%. At the same level the electron conversion factor is: T=5.42. In the

second case at the level 103 keV the cumulative gamma emission probability is 29.2%, the electron conversionfactor is: T=1.72.

Other weak beta and gamma emissions are presented in the box by points (…) and on the decay scheme bydashed lines.

The last row in the box 420 gives the (n, ) cross section for thermal neutrons in barns for the formation of Sm153.

Sm 153 is used in medical therapy of bone cancer in form of bone seeking radiopharmaceuticals. Gammaemission allows the follow up the distribution of radiopharmaceutical in the patient's body.

Half-life

46.284 (4) hNuclear Data Sheets 107, 507 (2006)

Radiation:

ß-= 100%ß energies (MeV):0.7036 49.4 % (max emission prob. )0.6339 31.3 % (not in box)0.8068 18.4 % (max energy level)...Gammas (keV):103.18 29.2 % T=1.72 (e-)

69.67 4.73 % T=5.42 (e-)

...Nuclear Data Sheets Volume 112, Issue 12, December 2011, Pages 2887–2996 Special Issue on ENDF/B-VII.1 Libraryhttp://dx.doi.org/10.1016/j.nds.2011.11.002Nuclear Data Sheets 107, 507 (2006)

Cross Section: Neutron Scattering and Absorption Properties, Handbook of Chemistry and Physics 2010 [27].

The nuclide Ra 226 is an isotope of the element radium (atomic number 88, chemical symbol Ra). There are 226nucleons in the nucleus consisting of 88 protons and 138 neutrons. Ra 226 is radioactive with a half-life of 1600years.


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0.9403 4.7843 MeV

0.0596 4.601 MeV

0.0353 186 keV

The colour yellow indicates that the nucleus decays through alpha emission. The alpha particle energy with thehighest emission probability is at 4.7843 MeV followed by 4.601 MeV. Additional alpha particles are alsoobserved – indicated by the dots. In contrast to beta emission (where only two beta energies are given – the mostprobable and the highest energy respectively), the alpha particle energies are listed according to decreasingemission probability.

At the top right hand corner of the box, the violet triangle indicates that Ra 226 undergoes decay by cluster

emission. This is a rare type of decay with a very small branching ratio (2.6•10–11). In this particular case thedecay is due to C 14 cluster emission. Further details are shown in the decay scheme.

At the bottom of the nuclide box, it can be seen that the cross section for thermal neutron capture to Ra 227 is

12.8 barns. The cross section for fission is very small < 5•10–5 barns.

Half-life: 1600(7) a, V.Chisté et al., Int.Conf. on Nuclear Data for Science andTechnology 2007

Radiation: α 4.78434(25) MeV, 94.038(40) % 4.601(1) MeV, 5.950(40) % ... γ 186.211(13) keV, 3.555(19) % ... V.Chisté et al., Laboratoire National Henri Becquerel, recommended data 2007

Ra 226: Extract from the Karlsruhe Nuclide

Chart, 8th Edition (2012) Ra 226 Decay Scheme


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C 14 3.2(16)E-9 %, Nucl.Data Sheets 77(1996)433

σ: σ 12.8(15) b, σ(f) <5E-5 b, S.Mughabghab, Atlas of Neutron Resonances, Resonance Parameters and Thermal Cross Sections Z=1-100, 5th Edition, Elsevier, Amsterdam (2006)

More information on decay schemes can be found on the Laboratoire National Henri Becquerelhere(http://www.nucleide.org/DDEP_WG/DDEPdata_by_Z.htm) .

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