Isotopes of tantalum

Isotopes of tantalum (₇₃Ta)
β−	180W
Standard atomic weight Ar°(Ta)
	180.94788±0.00002; 180.95±0.01 (abridged);
	view ; talk ; edit ;

Last updated April 13, 2024

Natural tantalum (₇₃Ta) consists of two stable isotopes: ¹⁸¹Ta (99.988%) and ^180m
Ta (0.012%).

There are also 35 known artificial radioisotopes, the longest-lived of which are ¹⁷⁹Ta with a half-life of 1.82 years, ¹⁸²Ta with a half-life of 114.43 days, ¹⁸³Ta with a half-life of 5.1 days, and ¹⁷⁷Ta with a half-life of 56.56 hours. All other isotopes have half-lives under a day, most under an hour. There are also numerous isomers, the most stable of which (other than ^180mTa) is ^178m1Ta with a half-life of 2.36 hours. All isotopes and nuclear isomers of tantalum are either radioactive or observationally stable, meaning that they are predicted to be radioactive but no actual decay has been observed.

Tantalum has been proposed as a "salting" material for nuclear weapons (cobalt is another, better-known salting material). A jacket of ¹⁸¹Ta, irradiated by the intense high-energy neutron flux from an exploding thermonuclear weapon, would transmute into the radioactive isotope ¹⁸²
Ta with a half-life of 114.43 days and produce approximately 1.12 MeV of gamma radiation, significantly increasing the radioactivity of the weapon's fallout for several months. Such a weapon is not known to have ever been built, tested, or used.^[4] While the conversion factor from absorbed dose (measured in Grays) to effective dose (measured in Sievert) for gamma rays is 1 while it is 50 for alpha radiation (i.e., a gamma dose of 1 Gray is equivalent to 1 Sievert whereas an alpha dose of 1 Gray is equivalent to 50 Sievert), gamma rays are only attenuated by shielding, not stopped. As such, alpha particles require incorporation to have an effect while gamma rays can have an effect via mere proximity. In military terms, this allows a gamma ray weapon to deny an area to either side as long as the dose is high enough, whereas radioactive contamination by alpha emitters which do not release significant amounts of gamma rays can be counteracted by ensuring the material is not incorporated.

List of isotopes

Nuclide ^{[n 1]}	Z	N	Isotopic mass (Da) ^{[n 2]}^{[n 3]}	Half-life ^{[n 4]}	Decay mode ^{[n 5]}	Daughter isotope ^{[n 6]}^{[n 7]}	Spin and parity ^{[n 8]}^{[n 4]}	Natural abundance (mole fraction)
Nuclide ^{[n 1]}	Excitation energy^{[n 4]}			Half-life ^{[n 4]}	Decay mode ^{[n 5]}	Daughter isotope ^{[n 6]}^{[n 7]}	Spin and parity ^{[n 8]}^{[n 4]}	Normal proportion	Range of variation
¹⁵⁵ Ta	73	82	154.97459(54)#	2.9+1.5 −1.1 ms^[5]	p	¹⁵⁴Hf	(11/2−)
^155m Ta	~323 keV			12+4 −3 μs^[6]	p	¹⁵⁴Hf	11/2−?
¹⁵⁶ Ta^[7]	73	83	155.97230(43)#	106(4) ms	p (71%)	¹⁵⁵Hf	(2−)
¹⁵⁶ Ta^[7]	73	83	155.97230(43)#	106(4) ms	β⁺ (29%)	¹⁵⁶Hf	(2−)
^156m Ta	102(7) keV			0.36(4) s	p	¹⁵⁵Hf	9+
¹⁵⁷ Ta	73	84	156.96819(22)	10.1(4) ms	α (91%)	¹⁵³Lu	1/2+
¹⁵⁷ Ta	73	84	156.96819(22)	10.1(4) ms	β⁺ (9%)	¹⁵⁷Hf	1/2+
^157m1 Ta	22(5) keV			4.3(1) ms			11/2−
^157m2 Ta	1593(9) keV			1.7(1) ms	α	¹⁵³Lu	(25/2−)
¹⁵⁸ Ta	73	85	157.96670(22)#	49(8) ms	α (96%)	¹⁵⁴Lu	(2−)
¹⁵⁸ Ta	73	85	157.96670(22)#	49(8) ms	β⁺ (4%)	¹⁵⁸Hf	(2−)
^158m Ta	141(9) keV			36.0(8) ms	α (93%)	¹⁵⁴Lu	(9+)
					IT	¹⁵⁸Ta
					β⁺	¹⁵⁸Hf
¹⁵⁹ Ta	73	86	158.963018(22)	1.04(9) s	β⁺ (66%)	¹⁵⁹Hf	(1/2+)
¹⁵⁹ Ta	73	86	158.963018(22)	1.04(9) s	α (34%)	¹⁵⁵Lu	(1/2+)
^159m Ta	64(5) keV			514(9) ms	α (56%)	¹⁵⁵Lu	(11/2−)
^159m Ta	64(5) keV			514(9) ms	β⁺ (44%)	¹⁵⁹Hf	(11/2−)
¹⁶⁰ Ta	73	87	159.96149(10)	1.70(20) s	α	¹⁵⁶Lu	(2#)−
¹⁶⁰ Ta	73	87	159.96149(10)	1.70(20) s	β⁺	¹⁶⁰Hf	(2#)−
^160m Ta	310(90)# keV			1.55(4) s	β⁺ (66%)	¹⁶⁰Hf	(9)+
^160m Ta	310(90)# keV			1.55(4) s	α (34%)	¹⁵⁶Lu	(9)+
¹⁶¹ Ta	73	88	160.95842(6)#	3# s	β⁺ (95%)	¹⁶¹Hf	1/2+#
¹⁶¹ Ta	73	88	160.95842(6)#	3# s	α (5%)	¹⁵⁷Lu	1/2+#
^161m Ta	50(50)# keV			2.89(12) s			11/2−#
¹⁶² Ta	73	89	161.95729(6)	3.57(12) s	β⁺ (99.92%)	¹⁶²Hf	3+#
¹⁶² Ta	73	89	161.95729(6)	3.57(12) s	α (.073%)	¹⁵⁸Lu	3+#
¹⁶³ Ta	73	90	162.95433(4)	10.6(18) s	β⁺ (99.8%)	¹⁶³Hf	1/2+#
¹⁶³ Ta	73	90	162.95433(4)	10.6(18) s	α (.2%)	¹⁵⁹Lu	1/2+#
¹⁶⁴ Ta	73	91	163.95353(3)	14.2(3) s	β⁺	¹⁶⁴Hf	(3+)
¹⁶⁵ Ta	73	92	164.950773(19)	31.0(15) s	β⁺	¹⁶⁵Hf	5/2−#
^165m Ta	60(30) keV						9/2−#
¹⁶⁶ Ta	73	93	165.95051(3)	34.4(5) s	β⁺	¹⁶⁶Hf	(2)+
¹⁶⁷ Ta	73	94	166.94809(3)	1.33(7) min	β⁺	¹⁶⁷Hf	(3/2+)
¹⁶⁸ Ta	73	95	167.94805(3)	2.0(1) min	β⁺	¹⁶⁸Hf	(2−,3+)
¹⁶⁹ Ta	73	96	168.94601(3)	4.9(4) min	β⁺	¹⁶⁹Hf	(5/2+)
¹⁷⁰ Ta	73	97	169.94618(3)	6.76(6) min	β⁺	¹⁷⁰Hf	(3)(+#)
¹⁷¹ Ta	73	98	170.94448(3)	23.3(3) min	β⁺	¹⁷¹Hf	(5/2−)
¹⁷² Ta	73	99	171.94490(3)	36.8(3) min	β⁺	¹⁷²Hf	(3+)
¹⁷³ Ta	73	100	172.94375(3)	3.14(13) h	β⁺	¹⁷³Hf	5/2−
¹⁷⁴ Ta	73	101	173.94445(3)	1.14(8) h	β⁺	¹⁷⁴Hf	3+
¹⁷⁵ Ta	73	102	174.94374(3)	10.5(2) h	β⁺	¹⁷⁵Hf	7/2+
¹⁷⁶ Ta	73	103	175.94486(3)	8.09(5) h	β⁺	¹⁷⁶Hf	(1)−
^176m1 Ta	103.0(10) keV			1.1(1) ms	IT	¹⁷⁶Ta	(+)
^176m2 Ta	1372.6(11)+X keV			3.8(4) µs			(14−)
^176m3 Ta	2820(50) keV			0.97(7) ms			(20−)
¹⁷⁷ Ta	73	104	176.944472(4)	56.56(6) h	β⁺	¹⁷⁷Hf	7/2+
^177m1 Ta	73.36(15) keV			410(7) ns			9/2−
^177m2 Ta	186.15(6) keV			3.62(10) µs			5/2−
^177m3 Ta	1355.01(19) keV			5.31(25) µs			21/2−
^177m4 Ta	4656.3(5) keV			133(4) µs			49/2−
¹⁷⁸ Ta	73	105	177.945778(16)	9.31(3) min	β⁺	¹⁷⁸Hf	1+
^178m1 Ta	100(50)# keV			2.36(8) h	β⁺	¹⁷⁸Hf	(7)−
^178m2 Ta	1570(50)# keV			59(3) ms			(15−)
^178m3 Ta	3000(50)# keV			290(12) ms			(21−)
¹⁷⁹ Ta	73	106	178.9459295(23)	1.82(3) y	EC	¹⁷⁹Hf	7/2+
^179m1 Ta	30.7(1) keV			1.42(8) µs			(9/2)−
^179m2 Ta	520.23(18) keV			335(45) ns			(1/2)+
^179m3 Ta	1252.61(23) keV			322(16) ns			(21/2−)
^179m4 Ta	1317.3(4) keV			9.0(2) ms	IT	¹⁷⁹Ta	(25/2+)
^179m5 Ta	1327.9(4) keV			1.6(4) µs			(23/2−)
^179m6 Ta	2639.3(5) keV			54.1(17) ms			(37/2+)
¹⁸⁰ Ta	73	107	179.9474648(24)	8.152(6) h	EC (86%)	¹⁸⁰Hf	1+
¹⁸⁰ Ta	73	107	179.9474648(24)	8.152(6) h	β⁻ (14%)	¹⁸⁰W	1+
^180m1 Ta	77.1(8) keV			Observationally stable^{[n 9]}^{[n 10]}			9−	1.2(2)×10⁻⁴
^180m2 Ta	1452.40(18) keV			31.2(14) µs			15−
^180m3 Ta	3679.0(11) keV			2.0(5) µs			(22−)
^180m4 Ta	4171.0+X keV			17(5) µs			(23, 24, 25)
¹⁸¹ Ta	73	108	180.9479958(20)	Observationally stable^{[n 11]}			7/2+	0.99988(2)
^181m1 Ta	6.238(20) keV			6.05(12) µs			9/2−
^181m2 Ta	615.21(3) keV			18(1) µs			1/2+
^181m3 Ta	1485(3) keV			25(2) µs			21/2−
^181m4 Ta	2230(3) keV			210(20) µs			29/2−
¹⁸² Ta	73	109	181.9501518(19)	114.43(3) d	β⁻	¹⁸²W	3−
^182m1 Ta	16.263(3) keV			283(3) ms	IT	¹⁸²Ta	5+
^182m2 Ta	519.572(18) keV			15.84(10) min			10−
¹⁸³ Ta	73	110	182.9513726(19)	5.1(1) d	β⁻	¹⁸³W	7/2+
^183m Ta	73.174(12) keV			107(11) ns			9/2−
¹⁸⁴ Ta	73	111	183.954008(28)	8.7(1) h	β⁻	¹⁸⁴W	(5−)
¹⁸⁵ Ta	73	112	184.955559(15)	49.4(15) min	β⁻	¹⁸⁵W	(7/2+)#
^185m Ta	1308(29) keV			>1 ms			(21/2−)
¹⁸⁶ Ta	73	113	185.95855(6)	10.5(3) min	β⁻	¹⁸⁶W	(2−,3−)
^186m Ta				1.54(5) min
¹⁸⁷ Ta	73	114	186.96053(21)#	2# min [>300 ns]	β⁻	¹⁸⁷W	7/2+#
¹⁸⁸ Ta	73	115	187.96370(21)#	20# s [>300 ns]	β⁻	¹⁸⁸W
¹⁸⁹ Ta	73	116	188.96583(32)#	3# s [>300 ns]			7/2+#
¹⁹⁰ Ta	73	117	189.96923(43)#	0.3# s
This table header & footer: view

↑ ^mTa – Excited nuclear isomer.
↑ ( ) – Uncertainty (1σ) is given in concise form in parentheses after the corresponding last digits.
↑ # – Atomic mass marked #: value and uncertainty derived not from purely experimental data, but at least partly from trends from the Mass Surface (TMS).
1 2 3 # – Values marked # are not purely derived from experimental data, but at least partly from trends of neighboring nuclides (TNN).
↑ Modes of decay:
EC: Electron capture
IT: Isomeric transition
p: Proton emission
↑ Bold italics symbol as daughter – Daughter product is nearly stable.
↑ Bold symbol as daughter – Daughter product is stable.
↑ ( ) spin value – Indicates spin with weak assignment arguments.
↑ Only known observationally stable nuclear isomer, believed to decay by isomeric transition to ¹⁸⁰Ta, β⁻ decay to ¹⁸⁰W, or electron capture to ¹⁸⁰Hf with a half-life over 2.9×10¹⁷ years;^[8] also theorized to undergo α decay to ¹⁷⁶Lu
↑ One of the few (observationally) stable odd-odd nuclei
↑ Believed to undergo α decay to ¹⁷⁷Lu

Tantalum-180m

The nuclide ^180m
Ta (m denotes a metastable state) has sufficient energy to decay in three ways: isomeric transition to the ground state of ¹⁸⁰
Ta, beta decay to ¹⁸⁰
W, and electron capture to ¹⁸⁰
Hf. However, no radioactivity from any decay mode of this nuclear isomer has ever been observed. As of 2023, the half-life of ^180mTa is calculated from experimental observation to be at least 2.9×10¹⁷ (290 quadrillion) years.^[8]^[9]^[10] The very slow decay of ^180m
Ta is attributed to its high spin (9 units) and the low spin of lower-lying states. Gamma or beta decay would require many units of angular momentum to be removed in a single step, so that the process would be very slow.^[11]

The very unusual nature of ^180mTa is that the ground state of this isotope is less stable than the isomer. This phenomenon is exhibited in bismuth-210m (^210mBi) and americium-242m (^242mAm), among other nuclides. ¹⁸⁰
Ta has a half-life of only 8 hours. ^180m
Ta is the only naturally occurring nuclear isomer (excluding radiogenic and cosmogenic short-living nuclides). It is also the rarest primordial nuclide in the Universe observed for any element that has any stable isotopes. In an s-process stellar environment with a thermal energy k_BT = 26 keV (i.e. a temperature of 300 million kelvin), the nuclear isomers are expected to be fully thermalized, meaning that ¹⁸⁰Ta rapidly transitions between spin states and its overall half-life is predicted to be 11 hours.^[12]

It is one of only five stable nuclides to have both an odd number of protons and an odd number of neutrons, the other four stable odd-odd nuclides being ²H, ⁶Li, ¹⁰B and ¹⁴N.^[13]

Related Research Articles

Stable nuclides are nuclides that are not radioactive and so do not spontaneously undergo radioactive decay. When such nuclides are referred to in relation to specific elements, they are usually termed stable isotopes.

<span class="mw-page-title-main">Nuclear isomer</span> Metastable excited state of a nuclide

A nuclear isomer is a metastable state of an atomic nucleus, in which one or more nucleons (protons or neutrons) occupy excited state (higher energy) levels. "Metastable" describes nuclei whose excited states have half-lives 100 to 1000 times longer than the half-lives of the excited nuclear states that decay with a "prompt" half life (ordinarily on the order of 10⁻¹² seconds). The term "metastable" is usually restricted to isomers with half-lives of 10⁻⁹ seconds or longer. Some references recommend 5 × 10⁻⁹ seconds to distinguish the metastable half life from the normal "prompt" gamma-emission half-life. Occasionally the half-lives are far longer than this and can last minutes, hours, or years. For example, the ^180m
₇₃Ta nuclear isomer survives so long (at least 10¹⁵ years) that it has never been observed to decay spontaneously. The half-life of a nuclear isomer can even exceed that of the ground state of the same nuclide, as shown by ^180m
₇₃Ta as well as ^192m2
₇₇Ir, ^210m
₈₃Bi, ^242m
₉₅Am and multiple holmium isomers.

In physics, induced gamma emission (IGE) refers to the process of fluorescent emission of gamma rays from excited nuclei, usually involving a specific nuclear isomer. It is analogous to conventional fluorescence, which is defined as the emission of a photon by an excited electron in an atom or molecule. In the case of IGE, nuclear isomers can store significant amounts of excitation energy for times long enough for them to serve as nuclear fluorescent materials. There are over 800 known nuclear isomers but almost all are too intrinsically radioactive to be considered for applications. As of 2006 there were two proposed nuclear isomers that appeared to be physically capable of IGE fluorescence in safe arrangements: tantalum-180m and hafnium-178m2.

Thorium (₉₀Th) has seven naturally occurring isotopes but none are stable. One isotope, ²³²Th, is relatively stable, with a half-life of 1.405×10¹⁰ years, considerably longer than the age of the Earth, and even slightly longer than the generally accepted age of the universe. This isotope makes up nearly all natural thorium, so thorium was considered to be mononuclidic. However, in 2013, IUPAC reclassified thorium as binuclidic, due to large amounts of ²³⁰Th in deep seawater. Thorium has a characteristic terrestrial isotopic composition and thus a standard atomic weight can be given.

Radium (₈₈Ra) has no stable or nearly stable isotopes, and thus a standard atomic weight cannot be given. The longest lived, and most common, isotope of radium is ²²⁶Ra with a half-life of 1600 years. ²²⁶Ra occurs in the decay chain of ²³⁸U. Radium has 34 known isotopes from ²⁰¹Ra to ²³⁴Ra.

There are 39 known isotopes of radon (₈₆Rn), from ¹⁹³Rn to ²³¹Rn; all are radioactive. The most stable isotope is ²²²Rn with a half-life of 3.823 days, which decays into ²¹⁸
Po. Six isotopes of radon, ^{217, 218, 219, 220, 221, 222}Rn, occur in trace quantities in nature as decay products of, respectively, ²¹⁷At, ²¹⁸At, ²²³Ra, ²²⁴Ra, ²²⁵Ra, and ²²⁶Ra. ²¹⁷Rn and ²²¹Rn are produced in rare branches in the decay chain of trace quantities of ²³⁷Np; ²²²Rn is an intermediate step in the decay chain of ²³⁸U; ²¹⁹Rn is an intermediate step in the decay chain of ²³⁵U; and ²²⁰Rn occurs in the decay chain of ²³²Th.

Bismuth (₈₃Bi) has 41 known isotopes, ranging from ¹⁸⁴Bi to ²²⁴Bi. Bismuth has no stable isotopes, but does have one very long-lived isotope; thus, the standard atomic weight can be given as 208.98040(1). Although bismuth-209 is now known to be radioactive, it has classically been considered to be a stable isotope because it has a half-life of approximately 2.01×10¹⁹ years, which is more than a billion times the age of the universe. Besides ²⁰⁹Bi, the most stable bismuth radioisotopes are ^210mBi with a half-life of 3.04 million years, ²⁰⁸Bi with a half-life of 368,000 years and ²⁰⁷Bi, with a half-life of 32.9 years, none of which occurs in nature. All other isotopes have half-lives under 1 year, most under a day. Of naturally occurring radioisotopes, the most stable is radiogenic ²¹⁰Bi with a half-life of 5.012 days. ^210mBi is unusual for being a nuclear isomer with a half-life multiple orders of magnitude longer than that of the ground state.

There are two natural isotopes of iridium (₇₇Ir), and 37 radioisotopes, the most stable radioisotope being ¹⁹²Ir with a half-life of 73.83 days, and many nuclear isomers, the most stable of which is ^192m2Ir with a half-life of 241 years. All other isomers have half-lives under a year, most under a day. All isotopes of iridium are either radioactive or observationally stable, meaning that they are predicted to be radioactive but no actual decay has been observed.

Naturally occurring rhenium (₇₅Re) is 37.4% ¹⁸⁵Re, which is stable (although it is predicted to decay), and 62.6% ¹⁸⁷Re, which is unstable but has a very long half-life (4.12×10¹⁰ years). Among elements with a known stable isotope, only indium and tellurium similarly occur with a stable isotope in lower abundance than the long-lived radioactive isotope.

Naturally occurring xenon (₅₄Xe) consists of seven stable isotopes and two very long-lived isotopes. Double electron capture has been observed in ¹²⁴Xe and double beta decay in ¹³⁶Xe, which are among the longest measured half-lives of all nuclides. The isotopes ¹²⁶Xe and ¹³⁴Xe are also predicted to undergo double beta decay, but this has never been observed in these isotopes, so they are considered to be stable. Beyond these stable forms, 32 artificial unstable isotopes and various isomers have been studied, the longest-lived of which is ¹²⁷Xe with a half-life of 36.345 days. All other isotopes have half-lives less than 12 days, most less than 20 hours. The shortest-lived isotope, ¹⁰⁸Xe, has a half-life of 58 μs, and is the heaviest known nuclide with equal numbers of protons and neutrons. Of known isomers, the longest-lived is ^131mXe with a half-life of 11.934 days. ¹²⁹Xe is produced by beta decay of ¹²⁹I ; ^131mXe, ¹³³Xe, ^133mXe, and ¹³⁵Xe are some of the fission products of both ²³⁵U and ²³⁹Pu, so are used as indicators of nuclear explosions.

There are 39 known isotopes and 17 nuclear isomers of tellurium (₅₂Te), with atomic masses that range from 104 to 142. These are listed in the table below.

Naturally occurring chromium (₂₄Cr) is composed of four stable isotopes; ⁵⁰Cr, ⁵²Cr, ⁵³Cr, and ⁵⁴Cr with ⁵²Cr being the most abundant (83.789% natural abundance). ⁵⁰Cr is suspected of decaying by β⁺β⁺ to ⁵⁰Ti with a half-life of (more than) 1.8×10¹⁷ years. Twenty-two radioisotopes, all of which are entirely synthetic, have been characterized, the most stable being ⁵¹Cr with a half-life of 27.7 days. All of the remaining radioactive isotopes have half-lives that are less than 24 hours and the majority of these have half-lives that are less than 1 minute. This element also has two meta states, ^45mCr, the more stable one, and ^59mCr, the least stable isotope or isomer.

Americium (₉₅Am) is an artificial element, and thus a standard atomic weight cannot be given. Like all artificial elements, it has no known stable isotopes. The first isotope to be synthesized was ²⁴¹Am in 1944. The artificial element decays by ejecting alpha particles. Americium has an atomic number of 95. Despite ²⁴³
Am being an order of magnitude longer lived than ²⁴¹
Am, the former is harder to obtain than the latter as more of it is present in spent nuclear fuel.

Curium (₉₆Cm) is an artificial element with an atomic number of 96. Because it is an artificial element, a standard atomic weight cannot be given, and it has no stable isotopes. The first isotope synthesized was ²⁴²Cm in 1944, which has 146 neutrons.

Mendelevium (₁₀₁Md) is a synthetic element, and thus a standard atomic weight cannot be given. Like all artificial elements, it has no stable isotopes. The first isotope to be synthesized was ²⁵⁶Md in 1955. There are 17 known radioisotopes, ranging in atomic mass from ²⁴⁴Md to ²⁶⁰Md, and 5 isomers. The longest-lived isotope is ²⁵⁸Md with a half-life of 51.3 days, and the longest-lived isomer is ^258mMd with a half-life of 57 minutes.

Dubnium (₁₀₅Db) is a synthetic element, thus a standard atomic weight cannot be given. Like all synthetic elements, it has no stable isotopes. The first isotope to be synthesized was ²⁶¹Db in 1968. Thirteen radioisotopes are known, ranging from ²⁵⁵Db to ²⁷⁰Db, along with one isomer (^257mDb); two more isomers have been reported but are unconfirmed. The longest-lived known isotope is ²⁶⁸Db with a half-life of 16 hours.

Seaborgium (₁₀₆Sg) is a synthetic element and so has no stable isotopes. A standard atomic weight cannot be given. The first isotope to be synthesized was ²⁶³Sg in 1974. There are 13 known radioisotopes from ²⁵⁸Sg to ²⁷¹Sg and 4 known isomers. The longest-lived isotope is ²⁶⁹Sg with a half-life of 14 minutes.

Yrast is a technical term in nuclear physics that refers to a state of a nucleus with a minimum of energy for a given angular momentum. Yr is a Swedish adjective sharing the same root as the English whirl. Yrast is the superlative of yr and can be translated whirlingest, although it literally means "dizziest" or "most bewildered". The yrast levels are vital to understanding reactions, such as off-center heavy ion collisions, that result in high-spin states.

<span class="mw-page-title-main">Even and odd atomic nuclei</span> Nuclear physics classification method

In nuclear physics, properties of a nucleus depend on evenness or oddness of its atomic number Z, neutron number N and, consequently, of their sum, the mass number A. Most importantly, oddness of both Z and N tends to lower the nuclear binding energy, making odd nuclei generally less stable. This effect is not only experimentally observed, but is included in the semi-empirical mass formula and explained by some other nuclear models, such as the nuclear shell model. This difference of nuclear binding energy between neighbouring nuclei, especially of odd-A isobars, has important consequences for beta decay.

References

↑ Kondev, F. G.; Wang, M.; Huang, W. J.; Naimi, S.; Audi, G. (2021). "The NUBASE2020 evaluation of nuclear properties" (PDF). Chinese Physics C. 45 (3): 030001. doi:10.1088/1674-1137/abddae.
↑ "Standard Atomic Weights: Tantalum". CIAAW. 2005.
↑ Prohaska, Thomas; Irrgeher, Johanna; Benefield, Jacqueline; Böhlke, John K.; Chesson, Lesley A.; Coplen, Tyler B.; Ding, Tiping; Dunn, Philip J. H.; Gröning, Manfred; Holden, Norman E.; Meijer, Harro A. J. (2022-05-04). "Standard atomic weights of the elements 2021 (IUPAC Technical Report)". Pure and Applied Chemistry. doi:10.1515/pac-2019-0603. ISSN 1365-3075.
↑ D. T. Win; M. Al Masum (2003). "Weapons of Mass Destruction" (PDF). Assumption University Journal of Technology . 6 (4): 199–219.
↑ Page, R. D.; Bianco, L.; Darby, I. G.; Uusitalo, J.; Joss, D. T.; Grahn, T.; Herzberg, R.-D.; Pakarinen, J.; Thomson, J.; Eeckhaudt, S.; Greenlees, P. T.; Jones, P. M.; Julin, R.; Juutinen, S.; Ketelhut, S.; Leino, M.; Leppänen, A.-P.; Nyman, M.; Rahkila, P.; Sarén, J.; Scholey, C.; Steer, A.; Hornillos, M. B. Gómez; Al-Khalili, J. S.; Cannon, A. J.; Stevenson, P. D.; Ertürk, S.; Gall, B.; Hadinia, B.; Venhart, M.; Simpson, J. (26 June 2007). "α decay of Re 159 and proton emission from Ta 155". Physical Review C. 75 (6): 061302. Bibcode:2007PhRvC..75f1302P. doi:10.1103/PhysRevC.75.061302. ISSN 0556-2813.
↑ Uusitalo, J.; Davids, C. N.; Woods, P. J.; Seweryniak, D.; Sonzogni, A. A.; Batchelder, J. C.; Bingham, C. R.; Davinson, T.; deBoer, J.; Henderson, D. J.; Maier, H. J.; Ressler, J. J.; Slinger, R.; Walters, W. B. (1 June 1999). "Proton emission from the closed neutron shell nucleus 155 Ta". Physical Review C. 59 (6): R2975–R2978. Bibcode:1999PhRvC..59.2975U. doi:10.1103/PhysRevC.59.R2975. ISSN 0556-2813 . Retrieved 12 June 2023.
↑ Darby, I. G.; Page, R. D.; Joss, D. T.; Bianco, L.; Grahn, T.; Judson, D. S.; Simpson, J.; Eeckhaudt, S.; Greenlees, P. T.; Jones, P. M.; Julin, R.; Juutinen, S.; Ketelhut, S.; Leino, M.; Leppänen, A.-P.; Nyman, M.; Rahkila, P.; Sarén, J.; Scholey, C.; Steer, A. N.; Uusitalo, J.; Venhart, M.; Ertürk, S.; Gall, B.; Hadinia, B. (20 June 2011). "Precision measurements of proton emission from the ground states of Ta 156 and Re 160". Physical Review C. 83 (6): 064320. Bibcode:2011PhRvC..83f4320D. doi:10.1103/PhysRevC.83.064320. ISSN 0556-2813 . Retrieved 21 June 2023.
1 2 Arnquist, I. J.; Avignone III, F. T.; Barabash, A. S.; Barton, C. J.; Bhimani, K. H.; Blalock, E.; Bos, B.; Busch, M.; Buuck, M.; Caldwell, T. S.; Christofferson, C. D.; Chu, P.-H.; Clark, M. L.; Cuesta, C.; Detwiler, J. A.; Efremenko, Yu.; Ejiri, H.; Elliott, S. R.; Giovanetti, G. K.; Goett, J.; Green, M. P.; Gruszko, J.; Guinn, I. S.; Guiseppe, V. E.; Haufe, C. R.; Henning, R.; Aguilar, D. Hervas; Hoppe, E. W.; Hostiuc, A.; Kim, I.; Kouzes, R. T.; Lannen V., T. E.; Li, A.; López-Castaño, J. M.; Massarczyk, R.; Meijer, S. J.; Meijer, W.; Oli, T. K.; Paudel, L. S.; Pettus, W.; Poon, A. W. P.; Radford, D. C.; Reine, A. L.; Rielage, K.; Rouyer, A.; Ruof, N. W.; Schaper, D. C.; Schleich, S. J.; Smith-Gandy, T. A.; Tedeschi, D.; Thompson, J. D.; Varner, R. L.; Vasilyev, S.; Watkins, S. L.; Wilkerson, J. F.; Wiseman, C.; Xu, W.; Yu, C.-H. (13 October 2023). "Constraints on the Decay of ^180mTa". Phys. Rev. Lett. 131 (15): 152501. arXiv: 2306.01965 . doi:10.1103/PhysRevLett.131.152501.
↑ Conover, Emily (2016-10-03). "Rarest nucleus reluctant to decay" . Retrieved 2016-10-05.
↑ Lehnert, Björn; Hult, Mikael; Lutter, Guillaume; Zuber, Kai (2017). "Search for the decay of nature's rarest isotope ^180mTa". Physical Review C. 95 (4): 044306. arXiv: 1609.03725 . Bibcode:2017PhRvC..95d4306L. doi:10.1103/PhysRevC.95.044306. S2CID 118497863.
↑ Quantum mechanics for engineers Leon van Dommelen, Florida State University
↑ P. Mohr, F. Kaeppeler, and R. Gallino (2007). "Survival of Nature's Rarest Isotope 180Ta under Stellar Conditions". Phys. Rev. C. 75: 012802. arXiv: astro-ph/0612427 . doi:10.1103/PhysRevC.75.012802. S2CID 44724195.{{cite journal}}: CS1 maint: multiple names: authors list (link)
↑ Various (2002). Lide, David R. (ed.). Handbook of Chemistry & Physics (88th ed.). CRC. ISBN 978-0-8493-0486-6. OCLC 179976746. Archived from the original on 24 July 2017. Retrieved 2008-05-23.

Isotope masses from:
- Audi, Georges; Bersillon, Olivier; Blachot, Jean; Wapstra, Aaldert Hendrik (2003), "The NUBASE evaluation of nuclear and decay properties", Nuclear Physics A, 729: 3–128, Bibcode:2003NuPhA.729....3A, doi:10.1016/j.nuclphysa.2003.11.001
Isotopic compositions and standard atomic masses from:
- de Laeter, John Robert; Böhlke, John Karl; De Bièvre, Paul; Hidaka, Hiroshi; Peiser, H. Steffen; Rosman, Kevin J. R.; Taylor, Philip D. P. (2003). "Atomic weights of the elements. Review 2000 (IUPAC Technical Report)". Pure and Applied Chemistry . 75 (6): 683–800. doi: 10.1351/pac200375060683 .
- Wieser, Michael E. (2006). "Atomic weights of the elements 2005 (IUPAC Technical Report)". Pure and Applied Chemistry . 78 (11): 2051–2066. doi: 10.1351/pac200678112051 .

"News & Notices: Standard Atomic Weights Revised". International Union of Pure and Applied Chemistry. 19 October 2005.
Half-life, spin, and isomer data selected from the following sources.
- Audi, Georges; Bersillon, Olivier; Blachot, Jean; Wapstra, Aaldert Hendrik (2003), "The NUBASE evaluation of nuclear and decay properties", Nuclear Physics A, 729: 3–128, Bibcode:2003NuPhA.729....3A, doi:10.1016/j.nuclphysa.2003.11.001
- National Nuclear Data Center. "NuDat 2.x database". Brookhaven National Laboratory.
- Holden, Norman E. (2004). "11. Table of the Isotopes". In Lide, David R. (ed.). CRC Handbook of Chemistry and Physics (85th ed.). Boca Raton, Florida: CRC Press. ISBN 978-0-8493-0485-9.

This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.

[5] Ta – Excited nuclear isomer.

[6] ( ) – Uncertainty (1σ) is given in concise form in parentheses after the corresponding last digits.

[TMS-7] # – Atomic mass marked #: value and uncertainty derived not from purely experimental data, but at least partly from trends from the Mass Surface (TMS).

[TNN-8] 1 2 3 # – Values marked # are not purely derived from experimental data, but at least partly from trends of neighboring nuclides (TNN).

[9] Modes of decay:
EC: Electron capture
IT: Isomeric transition
p: Proton emission

[10] Bold italics symbol as daughter – Daughter product is nearly stable.

[11] Bold symbol as daughter – Daughter product is stable.

[12] ( ) spin value – Indicates spin with weak assignment arguments.

[17] Only known observationally stable nuclear isomer, believed to decay by isomeric transition to ¹⁸⁰Ta, β⁻ decay to ¹⁸⁰W, or electron capture to ¹⁸⁰Hf with a half-life over 2.9×10¹⁷ years;^[8] also theorized to undergo α decay to ¹⁷⁶Lu

[18] One of the few (observationally) stable odd-odd nuclei

[19] Believed to undergo α decay to ¹⁷⁷Lu

[NUBASE2020-1] Kondev, F. G.; Wang, M.; Huang, W. J.; Naimi, S.; Audi, G. (2021). "The NUBASE2020 evaluation of nuclear properties" (PDF). Chinese Physics C. 45 (3): 030001. doi:10.1088/1674-1137/abddae.

[2] "Standard Atomic Weights: Tantalum". CIAAW. 2005.

[CIAAW2021-3] Prohaska, Thomas; Irrgeher, Johanna; Benefield, Jacqueline; Böhlke, John K.; Chesson, Lesley A.; Coplen, Tyler B.; Ding, Tiping; Dunn, Philip J. H.; Gröning, Manfred; Holden, Norman E.; Meijer, Harro A. J. (2022-05-04). "Standard atomic weights of the elements 2021 (IUPAC Technical Report)". Pure and Applied Chemistry. doi:10.1515/pac-2019-0603. ISSN 1365-3075.

[4] D. T. Win; M. Al Masum (2003). "Weapons of Mass Destruction" (PDF). Assumption University Journal of Technology . 6 (4): 199–219.

[13] Page, R. D.; Bianco, L.; Darby, I. G.; Uusitalo, J.; Joss, D. T.; Grahn, T.; Herzberg, R.-D.; Pakarinen, J.; Thomson, J.; Eeckhaudt, S.; Greenlees, P. T.; Jones, P. M.; Julin, R.; Juutinen, S.; Ketelhut, S.; Leino, M.; Leppänen, A.-P.; Nyman, M.; Rahkila, P.; Sarén, J.; Scholey, C.; Steer, A.; Hornillos, M. B. Gómez; Al-Khalili, J. S.; Cannon, A. J.; Stevenson, P. D.; Ertürk, S.; Gall, B.; Hadinia, B.; Venhart, M.; Simpson, J. (26 June 2007). "α decay of Re 159 and proton emission from Ta 155". Physical Review C. 75 (6): 061302. Bibcode:2007PhRvC..75f1302P. doi:10.1103/PhysRevC.75.061302. ISSN 0556-2813.

[14] Uusitalo, J.; Davids, C. N.; Woods, P. J.; Seweryniak, D.; Sonzogni, A. A.; Batchelder, J. C.; Bingham, C. R.; Davinson, T.; deBoer, J.; Henderson, D. J.; Maier, H. J.; Ressler, J. J.; Slinger, R.; Walters, W. B. (1 June 1999). "Proton emission from the closed neutron shell nucleus 155 Ta". Physical Review C. 59 (6): R2975–R2978. Bibcode:1999PhRvC..59.2975U. doi:10.1103/PhysRevC.59.R2975. ISSN 0556-2813 . Retrieved 12 June 2023.

[15] Darby, I. G.; Page, R. D.; Joss, D. T.; Bianco, L.; Grahn, T.; Judson, D. S.; Simpson, J.; Eeckhaudt, S.; Greenlees, P. T.; Jones, P. M.; Julin, R.; Juutinen, S.; Ketelhut, S.; Leino, M.; Leppänen, A.-P.; Nyman, M.; Rahkila, P.; Sarén, J.; Scholey, C.; Steer, A. N.; Uusitalo, J.; Venhart, M.; Ertürk, S.; Gall, B.; Hadinia, B. (20 June 2011). "Precision measurements of proton emission from the ground states of Ta 156 and Re 160". Physical Review C. 83 (6): 064320. Bibcode:2011PhRvC..83f4320D. doi:10.1103/PhysRevC.83.064320. ISSN 0556-2813 . Retrieved 21 June 2023.

[180mTa_2023-16] 1 2 Arnquist, I. J.; Avignone III, F. T.; Barabash, A. S.; Barton, C. J.; Bhimani, K. H.; Blalock, E.; Bos, B.; Busch, M.; Buuck, M.; Caldwell, T. S.; Christofferson, C. D.; Chu, P.-H.; Clark, M. L.; Cuesta, C.; Detwiler, J. A.; Efremenko, Yu.; Ejiri, H.; Elliott, S. R.; Giovanetti, G. K.; Goett, J.; Green, M. P.; Gruszko, J.; Guinn, I. S.; Guiseppe, V. E.; Haufe, C. R.; Henning, R.; Aguilar, D. Hervas; Hoppe, E. W.; Hostiuc, A.; Kim, I.; Kouzes, R. T.; Lannen V., T. E.; Li, A.; López-Castaño, J. M.; Massarczyk, R.; Meijer, S. J.; Meijer, W.; Oli, T. K.; Paudel, L. S.; Pettus, W.; Poon, A. W. P.; Radford, D. C.; Reine, A. L.; Rielage, K.; Rouyer, A.; Ruof, N. W.; Schaper, D. C.; Schleich, S. J.; Smith-Gandy, T. A.; Tedeschi, D.; Thompson, J. D.; Varner, R. L.; Vasilyev, S.; Watkins, S. L.; Wilkerson, J. F.; Wiseman, C.; Xu, W.; Yu, C.-H. (13 October 2023). "Constraints on the Decay of ^180mTa". Phys. Rev. Lett. 131 (15): 152501. arXiv: 2306.01965 . doi:10.1103/PhysRevLett.131.152501.

[20] Conover, Emily (2016-10-03). "Rarest nucleus reluctant to decay" . Retrieved 2016-10-05.

[21] Lehnert, Björn; Hult, Mikael; Lutter, Guillaume; Zuber, Kai (2017). "Search for the decay of nature's rarest isotope ^180mTa". Physical Review C. 95 (4): 044306. arXiv: 1609.03725 . Bibcode:2017PhRvC..95d4306L. doi:10.1103/PhysRevC.95.044306. S2CID 118497863.

[22] Quantum mechanics for engineers Leon van Dommelen, Florida State University

[23] P. Mohr, F. Kaeppeler, and R. Gallino (2007). "Survival of Nature's Rarest Isotope 180Ta under Stellar Conditions". Phys. Rev. C. 75: 012802. arXiv: astro-ph/0612427 . doi:10.1103/PhysRevC.75.012802. S2CID 44724195.{{cite journal}}: CS1 maint: multiple names: authors list (link)

[24] Various (2002). Lide, David R. (ed.). Handbook of Chemistry & Physics (88th ed.). CRC. ISBN 978-0-8493-0486-6. OCLC 179976746. Archived from the original on 24 July 2017. Retrieved 2008-05-23.

[1]

[2]

[3]

[4]

[n 1]

[n 2]

[n 3]

[n 4]

[n 5]

[n 6]

[n 7]

[n 8]

[5]

[6]

[7]

[n 9]

[n 10]

[n 11]

[8]

[9]

[10]

[11]

[12]

[13]

Isotopes of tantalum

Contents

List of isotopes

Tantalum-180m

Related Research Articles

References