Isotopes of xenon
Encyclopedia
Naturally occurring xenon
(Xe) is made of nine stable
isotope
s. (124Xe, 126Xe, 134Xe and 136Xe are predicted to undergo double beta decay
, but this has never been observed, so they are considered to be stable.) Xenon has the second highest number of stable isotopes. Only tin
, with 10 stable isotopes, has more. Beyond these stable forms, there are over 40 unstable isotopes and isomers that have been studied, the longest-lived of which is 127Xe with a half-life
of 36.345 days. Of known isomers, the longest-lived is 131mXe with a half-life of 11.934 days. 129Xe is produced by beta decay
of 129I
(half-life
: 16 million years); 131mXe, 133Xe, 133mXe, and 135Xe are some of the fission product
s of both 235U
and 239Pu
, and therefore used as indicators of nuclear explosion
s.
The artificial isotope 135Xe
is of considerable significance in the operation of nuclear fission reactors
. 135Xe has a huge cross section for thermal neutrons, 2.65×106 barns
, so it acts as a neutron absorber or "poison
" that can slow or stop
the chain reaction after a period of operation. This was discovered in the earliest nuclear reactors built by the American Manhattan Project
for plutonium
production. Fortunately the designers had made provisions in the design to increase the reactor's reactivity (the number of neutrons per fission that go on to fission other atoms of nuclear fuel).
Relatively high concentrations of radioactive xenon isotopes are also found emanating from nuclear reactors due to the release of this fission gas from cracked fuel rods or fissioning of uranium in cooling water. The concentrations of these isotopes are still usually low compared to naturally occurring radioactive noble gas
es such as 222Rn.
Because xenon is a tracer for two parent isotopes, Xe isotope ratios
in meteorite
s are a powerful tool for studying the formation of the solar system. The I-Xe method of dating
gives the time elapsed between nucleosynthesis
and the condensation of a solid object from the solar nebula
(Xenon being a gas, only that part of it which formed after condensation will be present inside the object). Xenon isotopes are also a powerful tool for understanding terrestrial differentiation
. Excess 129Xe found in carbon dioxide
well gases from New Mexico
was believed to be from the decay of mantle
-derived gases soon after Earth's formation.
Standard atomic mass: 131.293(6) u
-133 (brand name Xeneisol, ATC code ) is an isotope of Xenon
. It is a radionuclide
that is inhaled to assess pulmonary function, and to image the lung
s. It is also often used to image blood flow, particularly in the brain
. 133Xe is also an important fission product
.
for information on this synthetic isotope. Go to Table of nuclides
for a bonus external link.
Xenon
Xenon is a chemical element with the symbol Xe and atomic number 54. The element name is pronounced or . A colorless, heavy, odorless noble gas, xenon occurs in the Earth's atmosphere in trace amounts...
(Xe) is made of nine stable
Stable isotope
Stable isotopes are chemical isotopes that may or may not be radioactive, but if radioactive, have half-lives too long to be measured.Only 90 nuclides from the first 40 elements are energetically stable to any kind of decay save proton decay, in theory...
isotope
Isotope
Isotopes are variants of atoms of a particular chemical element, which have differing numbers of neutrons. Atoms of a particular element by definition must contain the same number of protons but may have a distinct number of neutrons which differs from atom to atom, without changing the designation...
s. (124Xe, 126Xe, 134Xe and 136Xe are predicted to undergo double beta decay
Double beta decay
Double beta decay is a radioactive decay process where a nucleus releases two beta rays as a single process.In double-beta decay, two neutrons in the nucleus are converted to protons, and two electrons and two electron antineutrinos are emitted...
, but this has never been observed, so they are considered to be stable.) Xenon has the second highest number of stable isotopes. Only tin
Tin
Tin is a chemical element with the symbol Sn and atomic number 50. It is a main group metal in group 14 of the periodic table. Tin shows chemical similarity to both neighboring group 14 elements, germanium and lead and has two possible oxidation states, +2 and the slightly more stable +4...
, with 10 stable isotopes, has more. Beyond these stable forms, there are over 40 unstable isotopes and isomers that have been studied, the longest-lived of which is 127Xe with a half-life
Half-life
Half-life, abbreviated t½, is the period of time it takes for the amount of a substance undergoing decay to decrease by half. The name was originally used to describe a characteristic of unstable atoms , but it may apply to any quantity which follows a set-rate decay.The original term, dating to...
of 36.345 days. Of known isomers, the longest-lived is 131mXe with a half-life of 11.934 days. 129Xe is produced by beta decay
Beta decay
In nuclear physics, beta decay is a type of radioactive decay in which a beta particle is emitted from an atom. There are two types of beta decay: beta minus and beta plus. In the case of beta decay that produces an electron emission, it is referred to as beta minus , while in the case of a...
of 129I
Iodine
Iodine is a chemical element with the symbol I and atomic number 53. The name is pronounced , , or . The name is from the , meaning violet or purple, due to the color of elemental iodine vapor....
(half-life
Half-life
Half-life, abbreviated t½, is the period of time it takes for the amount of a substance undergoing decay to decrease by half. The name was originally used to describe a characteristic of unstable atoms , but it may apply to any quantity which follows a set-rate decay.The original term, dating to...
: 16 million years); 131mXe, 133Xe, 133mXe, and 135Xe are some of the fission product
Fission product
Nuclear fission products are the atomic fragments left after a large atomic nucleus fissions. Typically, a large nucleus like that of uranium fissions by splitting into two smaller nuclei, along with a few neutrons and a large release of energy in the form of heat , gamma rays and neutrinos. The...
s of both 235U
Uranium-235
- References :* .* DOE Fundamentals handbook: Nuclear Physics and Reactor theory , .* A piece of U-235 the size of a grain of rice can produce energy equal to that contained in three tons of coal or fourteen barrels of oil. -External links:* * * one of the earliest articles on U-235 for the...
and 239Pu
Plutonium-239
Plutonium-239 is an isotope of plutonium. Plutonium-239 is the primary fissile isotope used for the production of nuclear weapons, although uranium-235 has also been used and is currently the secondary isotope. Plutonium-239 is also one of the three main isotopes demonstrated usable as fuel in...
, and therefore used as indicators of nuclear explosion
Nuclear explosion
A nuclear explosion occurs as a result of the rapid release of energy from an intentionally high-speed nuclear reaction. The driving reaction may be nuclear fission, nuclear fusion or a multistage cascading combination of the two, though to date all fusion based weapons have used a fission device...
s.
The artificial isotope 135Xe
Xenon-135
Xenon-135 is an unstable isotope of xenon with a half-life of about 9.2 hours. 135Xe is a fission product of uranium and Xe-135 is the most powerful known neutron-absorbing nuclear poison , with a significant effect on nuclear reactor operation...
is of considerable significance in the operation of nuclear fission reactors
Nuclear reactor
A nuclear reactor is a device to initiate and control a sustained nuclear chain reaction. Most commonly they are used for generating electricity and for the propulsion of ships. Usually heat from nuclear fission is passed to a working fluid , which runs through turbines that power either ship's...
. 135Xe has a huge cross section for thermal neutrons, 2.65×106 barns
Barn (unit)
A barn is a unit of area. Originally used in nuclear physics for expressing the cross sectional area of nuclei and nuclear reactions, today it is used in all fields of high energy physics to express the cross sections of any scattering process, and is best understood as a measure of the...
, so it acts as a neutron absorber or "poison
Nuclear poison
A neutron poison is a substance with a large neutron absorption cross-section in applications, such as nuclear reactors. In such applications, absorbing neutrons is normally an undesirable effect...
" that can slow or stop
Iodine pit
Iodine pit, also called iodine hole and xenon pit, is a temporary disabling of a nuclear reactor due to buildup of short-lived nuclear poisons in the core of a nuclear reactor. The main isotope responsible is xenon-135, mainly produced by natural decay of iodine-135. Iodine-135 is a weak neutron...
the chain reaction after a period of operation. This was discovered in the earliest nuclear reactors built by the American Manhattan Project
Manhattan Project
The Manhattan Project was a research and development program, led by the United States with participation from the United Kingdom and Canada, that produced the first atomic bomb during World War II. From 1942 to 1946, the project was under the direction of Major General Leslie Groves of the US Army...
for plutonium
Plutonium
Plutonium is a transuranic radioactive chemical element with the chemical symbol Pu and atomic number 94. It is an actinide metal of silvery-gray appearance that tarnishes when exposed to air, forming a dull coating when oxidized. The element normally exhibits six allotropes and four oxidation...
production. Fortunately the designers had made provisions in the design to increase the reactor's reactivity (the number of neutrons per fission that go on to fission other atoms of nuclear fuel).
Relatively high concentrations of radioactive xenon isotopes are also found emanating from nuclear reactors due to the release of this fission gas from cracked fuel rods or fissioning of uranium in cooling water. The concentrations of these isotopes are still usually low compared to naturally occurring radioactive noble gas
Noble gas
The noble gases are a group of chemical elements with very similar properties: under standard conditions, they are all odorless, colorless, monatomic gases, with very low chemical reactivity...
es such as 222Rn.
Because xenon is a tracer for two parent isotopes, Xe isotope ratios
Isotopic signature
An isotopic signature is a ratio of stable or unstable isotopes of particular elements found in an investigated material...
in meteorite
Meteorite
A meteorite is a natural object originating in outer space that survives impact with the Earth's surface. Meteorites can be big or small. Most meteorites derive from small astronomical objects called meteoroids, but they are also sometimes produced by impacts of asteroids...
s are a powerful tool for studying the formation of the solar system. The I-Xe method of dating
Radiometric dating
Radiometric dating is a technique used to date materials such as rocks, usually based on a comparison between the observed abundance of a naturally occurring radioactive isotope and its decay products, using known decay rates...
gives the time elapsed between nucleosynthesis
Nucleosynthesis
Nucleosynthesis is the process of creating new atomic nuclei from pre-existing nucleons . It is thought that the primordial nucleons themselves were formed from the quark–gluon plasma from the Big Bang as it cooled below two trillion degrees...
and the condensation of a solid object from the solar nebula
Solar nebula
In cosmogony, the nebular hypothesis is the most widely accepted model explaining the formation and evolution of the Solar System. There is evidence that it was first proposed in 1734 by Emanuel Swedenborg. Originally applied only to our own Solar System, this method of planetary system formation...
(Xenon being a gas, only that part of it which formed after condensation will be present inside the object). Xenon isotopes are also a powerful tool for understanding terrestrial differentiation
Planetary differentiation
In planetary science, planetary differentiation is the process of separating out different constituents of a planetary body as a consequence of their physical or chemical behaviour, where the body develops into compositionally distinct layers; the denser materials of a planet sink to the center,...
. Excess 129Xe found in carbon dioxide
Carbon dioxide
Carbon dioxide is a naturally occurring chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom...
well gases from New Mexico
New Mexico
New Mexico is a state located in the southwest and western regions of the United States. New Mexico is also usually considered one of the Mountain States. With a population density of 16 per square mile, New Mexico is the sixth-most sparsely inhabited U.S...
was believed to be from the decay of mantle
Mantle (geology)
The mantle is a part of a terrestrial planet or other rocky body large enough to have differentiation by density. The interior of the Earth, similar to the other terrestrial planets, is chemically divided into layers. The mantle is a highly viscous layer between the crust and the outer core....
-derived gases soon after Earth's formation.
Standard atomic mass: 131.293(6) u
Xenon-133
XenonXenon
Xenon is a chemical element with the symbol Xe and atomic number 54. The element name is pronounced or . A colorless, heavy, odorless noble gas, xenon occurs in the Earth's atmosphere in trace amounts...
-133 (brand name Xeneisol, ATC code ) is an isotope of Xenon
Xenon
Xenon is a chemical element with the symbol Xe and atomic number 54. The element name is pronounced or . A colorless, heavy, odorless noble gas, xenon occurs in the Earth's atmosphere in trace amounts...
. It is a radionuclide
Radionuclide
A radionuclide is an atom with an unstable nucleus, which is a nucleus characterized by excess energy available to be imparted either to a newly created radiation particle within the nucleus or to an atomic electron. The radionuclide, in this process, undergoes radioactive decay, and emits gamma...
that is inhaled to assess pulmonary function, and to image the lung
Lung
The lung is the essential respiration organ in many air-breathing animals, including most tetrapods, a few fish and a few snails. In mammals and the more complex life forms, the two lungs are located near the backbone on either side of the heart...
s. It is also often used to image blood flow, particularly in the brain
Brain
The brain is the center of the nervous system in all vertebrate and most invertebrate animals—only a few primitive invertebrates such as sponges, jellyfish, sea squirts and starfishes do not have one. It is located in the head, usually close to primary sensory apparatus such as vision, hearing,...
. 133Xe is also an important fission product
Fission product
Nuclear fission products are the atomic fragments left after a large atomic nucleus fissions. Typically, a large nucleus like that of uranium fissions by splitting into two smaller nuclei, along with a few neutrons and a large release of energy in the form of heat , gamma rays and neutrinos. The...
.
Xenon-135
Please visit the article Xenon-135Xenon-135
Xenon-135 is an unstable isotope of xenon with a half-life of about 9.2 hours. 135Xe is a fission product of uranium and Xe-135 is the most powerful known neutron-absorbing nuclear poison , with a significant effect on nuclear reactor operation...
for information on this synthetic isotope. Go to Table of nuclides
Table of nuclides
The tables listed below provide information on the basic properties of all nuclides.* Neutron + Element 1 - Element 24 * Element 25 - Element 48 * Element 49 - Element 72...
for a bonus external link.
Table
| nuclide symbol |
Z(p Proton The proton is a subatomic particle with the symbol or and a positive electric charge of 1 elementary charge. One or more protons are present in the nucleus of each atom, along with neutrons. The number of protons in each atom is its atomic number.... ) |
N(n Neutron The neutron is a subatomic hadron particle which has the symbol or , no net electric charge and a mass slightly larger than that of a proton. With the exception of hydrogen, nuclei of atoms consist of protons and neutrons, which are therefore collectively referred to as nucleons. The number of... ) |
isotopic mass (u) |
half-life | decay mode(s)Abbreviations: EC: Electron capture Electron capture Electron capture is a process in which a proton-rich nuclide absorbs an inner atomic electron and simultaneously emits a neutrino... IT: Isomeric transition Isomeric transition An isomeric transition is a radioactive decay process that involves emission of a gamma ray from an atom where the nucleus is in an excited metastable state, referred to in its excited state, as a nuclear isomer.... |
daughter isotope(s)Bold for stable isotopes |
nuclear spin |
representative isotopic composition (mole fraction) |
range of natural variation (mole fraction) |
|---|---|---|---|---|---|---|---|---|---|
| excitation energy | |||||||||
| 110Xe | 54 | 56 | 109.94428(14) | 310(190) ms [105(+35-25) ms] |
β+ Beta decay In nuclear physics, beta decay is a type of radioactive decay in which a beta particle is emitted from an atom. There are two types of beta decay: beta minus and beta plus. In the case of beta decay that produces an electron emission, it is referred to as beta minus , while in the case of a... |
110I | 0+ | ||
| α Alpha decay Alpha decay is a type of radioactive decay in which an atomic nucleus emits an alpha particle and thereby transforms into an atom with a mass number 4 less and atomic number 2 less... |
106Te | ||||||||
| 111Xe | 54 | 57 | 110.94160(33)# | 740(200) ms | β+ (90%) | 111I | 5/2+# | ||
| α (10%) | 107Te | ||||||||
| 112Xe | 54 | 58 | 111.93562(11) | 2.7(8) s | β+ (99.1%) | 112I | 0+ | ||
| α (.9%) | 108Te | ||||||||
| 113Xe | 54 | 59 | 112.93334(9) | 2.74(8) s | β+ (92.98%) | 113I | (5/2+)# | ||
| β+, p Proton emission Proton emission is a type of radioactive decay in which a proton is ejected from a nucleus. Proton emission can occur from high-lying excited states in a nucleus following a beta decay, in which case the process is known as beta-delayed proton emission, or can occur from the ground state of very... (7%) |
112Te | ||||||||
| α (.011%) | 109Te | ||||||||
| β+, α (.007%) | 109Sb | ||||||||
| 114Xe | 54 | 60 | 113.927980(12) | 10.0(4) s | β+ | 114I | 0+ | ||
| 115Xe | 54 | 61 | 114.926294(13) | 18(4) s | β+ (99.65%) | 115I | (5/2+) | ||
| β+, p (.34%) | 114Te | ||||||||
| β+, α (3×10−4%) | 111Sb | ||||||||
| 116Xe | 54 | 62 | 115.921581(14) | 59(2) s | β+ | 116I | 0+ | ||
| 117Xe | 54 | 63 | 116.920359(11) | 61(2) s | β+ (99.99%) | 117I | 5/2(+) | ||
| β+, p (.0029%) | 116Te | ||||||||
| 118Xe | 54 | 64 | 117.916179(11) | 3.8(9) min | β+ | 118I | 0+ | ||
| 119Xe | 54 | 65 | 118.915411(11) | 5.8(3) min | β+ | 119I | 5/2(+) | ||
| 120Xe | 54 | 66 | 119.911784(13) | 40(1) min | β+ | 120I | 0+ | ||
| 121Xe | 54 | 67 | 120.911462(12) | 40.1(20) min | β+ | 121I | (5/2+) | ||
| 122Xe | 54 | 68 | 121.908368(12) | 20.1(1) h | β+ | 122I | 0+ | ||
| 123Xe | 54 | 69 | 122.908482(10) | 2.08(2) h | EC Electron capture Electron capture is a process in which a proton-rich nuclide absorbs an inner atomic electron and simultaneously emits a neutrino... |
123I | 1/2+ | ||
| 123mXe | 185.18(22) keV | 5.49(26) µs | 7/2(-) | ||||||
| 124Xe | 54 | 70 | 123.905893(2) | Observationally StableSuspected of undergoing β+β+ decay to 124Te with a half-life Half-life Half-life, abbreviated t½, is the period of time it takes for the amount of a substance undergoing decay to decrease by half. The name was originally used to describe a characteristic of unstable atoms , but it may apply to any quantity which follows a set-rate decay.The original term, dating to... over 48×1015 years |
0+ | 9.52(3)×10−4 | |||
| 125Xe | 54 | 71 | 124.9063955(20) | 16.9(2) h | β+ | 125I | 1/2(+) | ||
| 125m1Xe | 252.60(14) keV | 56.9(9) s | IT Isomeric transition An isomeric transition is a radioactive decay process that involves emission of a gamma ray from an atom where the nucleus is in an excited metastable state, referred to in its excited state, as a nuclear isomer.... |
125Xe | 9/2(-) | ||||
| 125m2Xe | 295.86(15) keV | 0.14(3) µs | 7/2(+) | ||||||
| 126Xe | 54 | 72 | 125.904274(7) | Observationally StableSuspected of undergoing β+β+ decay to 126Te | 0+ | 8.90(2)×10−4 | |||
| 127Xe | 54 | 73 | 126.905184(4) | 36.345(3) d | EC | 127I | 1/2+ | ||
| 127mXe | 297.10(8) keV | 69.2(9) s | IT | 127Xe | 9/2- | ||||
| 128Xe | 54 | 74 | 127.9035313(15) | Observationally StableTheoretically capable of spontaneous fission Spontaneous fission Spontaneous fission is a form of radioactive decay characteristic of very heavy isotopes. Because the nuclear binding energy reaches a maximum at a nuclear mass greater than about 60 atomic mass units , spontaneous breakdown into smaller nuclei and single particles becomes possible at heavier masses... |
0+ | 0.019102(8) | |||
| 129XeUsed in a method of radiodating groundwater and to infer certain events in the Solar System's history | 54 | 75 | 128.9047794(8) | Observationally Stable | 1/2+ | 0.264006(82) | |||
| 129mXe | 236.14(3) keV | 8.88(2) d | IT | 129Xe | 11/2- | ||||
| 130Xe | 54 | 76 | 129.9035080(8) | Observationally Stable | 0+ | 0.040710(13) | |||
| 131XeFission product Fission product Nuclear fission products are the atomic fragments left after a large atomic nucleus fissions. Typically, a large nucleus like that of uranium fissions by splitting into two smaller nuclei, along with a few neutrons and a large release of energy in the form of heat , gamma rays and neutrinos. The... |
54 | 77 | 130.9050824(10) | Observationally Stable | 3/2+ | 0.212324(30) | |||
| 131mXe | 163.930(8) keV | 11.934(21) d | IT | 131Xe | 11/2- | ||||
| 132Xe | 54 | 78 | 131.9041535(10) | Observationally Stable | 0+ | 0.269086(33) | |||
| 132mXe | 2752.27(17) keV | 8.39(11) ms | IT | 132Xe | (10+) | ||||
| 133XeHas medical uses Nuclear medicine In nuclear medicine procedures, elemental radionuclides are combined with other elements to form chemical compounds, or else combined with existing pharmaceutical compounds, to form radiopharmaceuticals. These radiopharmaceuticals, once administered to the patient, can localize to specific organs... |
54 | 79 | 132.9059107(26) | 5.2475(5) d | β- | 133Cs | 3/2+ | ||
| 133mXe | 233.221(18) keV | 2.19(1) d | IT | 133Xe | 11/2- | ||||
| 134Xe | 54 | 80 | 133.9053945(9) | Observationally Stable Suspected of undergoing β-β- decay to 134Ba with a half-life over 11×1015 years | 0+ | 0.104357(21) | |||
| 134m1Xe | 1965.5(5) keV | 290(17) ms | IT | 134Xe | 7- | ||||
| 134m2Xe | 3025.2(15) keV | 5(1) µs | (10+) | ||||||
| 135XeMost powerful known neutron absorber, produced in nuclear power plants as a decay product Decay product In nuclear physics, a decay product is the remaining nuclide left over from radioactive decay. Radioactive decay often involves a sequence of steps... of 135I, itself a decay product of 135Te, a fission product Fission product Nuclear fission products are the atomic fragments left after a large atomic nucleus fissions. Typically, a large nucleus like that of uranium fissions by splitting into two smaller nuclei, along with a few neutrons and a large release of energy in the form of heat , gamma rays and neutrinos. The... . Normally absorbs neutrons in the high neutron flux Neutron flux The neutron flux is a quantity used in reactor physics corresponding to the total length travelled by all neutrons per unit time and volume . The neutron fluence is defined as the neutron flux integrated over a certain time period.... environments to become 136Xe; see iodine pit Iodine pit Iodine pit, also called iodine hole and xenon pit, is a temporary disabling of a nuclear reactor due to buildup of short-lived nuclear poisons in the core of a nuclear reactor. The main isotope responsible is xenon-135, mainly produced by natural decay of iodine-135. Iodine-135 is a weak neutron... for more information |
54 | 81 | 134.907227(5) | 9.14(2) h | β- | 135Cs | 3/2+ | ||
| 135mXe | 526.551(13) keV | 15.29(5) min | IT (99.99%) | 135Xe | 11/2- | ||||
| β- (.004%) | 135Cs | ||||||||
| 136Xe | 54 | 82 | 135.907219(8) | Observationally Stable Suspected of undergoing β-β- decay to 136Ba with a half-life over 1022 years | 0+ | 0.088573(44) | |||
| 136mXe | 1891.703(14) keV | 2.95(9) µs | 6+ | ||||||
| 137Xe | 54 | 83 | 136.911562(8) | 3.818(13) min | β- | 137Cs | 7/2- | ||
| 138Xe | 54 | 84 | 137.91395(5) | 14.08(8) min | β- | 138Cs | 0+ | ||
| 139Xe | 54 | 85 | 138.918793(22) | 39.68(14) s | β- | 139Cs | 3/2- | ||
| 140Xe | 54 | 86 | 139.92164(7) | 13.60(10) s | β- | 140Cs | 0+ | ||
| 141Xe | 54 | 87 | 140.92665(10) | 1.73(1) s | β- (99.45%) | 141Cs | 5/2(-#) | ||
| β-, n Neutron emission Neutron emission is a type of radioactive decay of atoms containing excess neutrons, in which a neutron is simply ejected from the nucleus. Two examples of isotopes which emit neutrons are helium-5 and beryllium-13... (.043%) |
140Cs | ||||||||
| 142Xe | 54 | 88 | 141.92971(11) | 1.22(2) s | β- (99.59%) | 142Cs | 0+ | ||
| β-, n (.41%) | 141Cs | ||||||||
| 143Xe | 54 | 89 | 142.93511(21)# | 0.511(6) s | β- | 143Cs | 5/2- | ||
| 144Xe | 54 | 90 | 143.93851(32)# | 0.388(7) s | β- | 144Cs | 0+ | ||
| β-, n | 143Cs | ||||||||
| 145Xe | 54 | 91 | 144.94407(32)# | 188(4) ms | β- | 145Cs | (3/2-)# | ||
| 146Xe | 54 | 92 | 145.94775(43)# | 146(6) ms | β- | 146Cs | 0+ | ||
| 147Xe | 54 | 93 | 146.95356(43)# | 130(80) ms [0.10(+10-5) s] |
β- | 147Cs | 3/2-# | ||
| β-, n | 146Cs | ||||||||