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D. Peterson, B. B. Back, R. V. F. Janssens, T. L. Khoo, C. J. Lister, D. Seweryniak, I. Ahmad, M. P. Carpenter, C. N. Davids, A. A. Hecht, C. L. Jiang, T. Lauritsen, X. Wang, S. Zhu, F. G. Kondev, A. Heinz, J. Qian, R. Winkler, P. Chowdhury, S. K. Tandel, and U. S. Tandel

The fragment mass analyzer at the ATLAS facility has been used to unambiguously identify the mass number associated with different decay modes of the nobelium isotopes produced via $204\mathrm{Pb}$$($$48\mathrm{Ca}$$,\mathrm{xn})$$252-x\mathrm{No}$ reactions. Isotopically pure ($>99.7$%) $204\mathrm{Pb}$ targets were used to reduce background from more favored reactions on heavier lead isotopes. Two spontaneous fission half-lives ($t_{1/2}=3.7_{-0.8}^{+1.1}$ and ${43}_{-15}^{+22}$ μs) were deduced from a total of 158 fission events. Both decays originate from $250\mathrm{No}$ rather than from neighboring isotopes as previously suggested. The longer activity most likely corresponds to a $K$ isomer in this nucleus. No conclusive evidence for an α branch was observed, resulting in upper limits of 2.1% for the shorter lifetime and 3.4% for the longer activity.

Yang Sun, Gui-Lu Long, Falih Al-Khudair, and Javid A. Sheikh

Recent experimental advances have made it possible to study excited structure in superheavy nuclei. The observed states have often been interpreted as quasiparticle excitations. We show that in superheavy nuclei collective vibrations systematically appear as low-energy excitation modes. By using the microscopic Triaxial Projected Shell Model, we make a detailed prediction on γ-vibrational states and their $E2$ transition probabilities to the ground state band in fermium and nobelium isotopes where active structure research is going on, and in $270\mathrm{Ds}$, the heaviest isotope where decay data have been obtained for the ground-state and for an isomeric state.

I.V. Toranzo a c, P. Sánchez-Moreno b c, R.O. Esquivel c d, J.S. Dehesa a c

Lawrencium is a chemical element with the symbol Lr and atomic number 103. It is a synthetic element and belongs to the actinide series of elements in the periodic table. Lawrencium is a highly radioactive metal that is not found naturally on Earth in significant amounts.

Key Characteristics of Lawrencium:

1. Radioactivity: Lawrencium is an extremely radioactive element, and all of its isotopes are unstable. Its most stable isotope, lawrencium-262, has a relatively short half-life of about 3.6 hours. Lawrencium emits alpha particles, beta particles, and gamma radiation during its radioactive decay.
2. Occurrence: Lawrencium is not found naturally on Earth. It is a synthetic element produced in nuclear reactors or through neutron bombardment of other elements, such as californium.
3. Chemical Properties: Lawrencium is a reactive element and readily forms compounds with oxygen, halogens, and other elements. It exhibits various oxidation states, with the +3 state being the most common. Due to its high radioactivity, lawrencium is challenging to handle and study.
4. Applications: Due to its extreme radioactivity and limited availability, lawrencium has very few practical applications. It is primarily used for scientific research purposes, particularly in the study of nuclear reactions and the behavior of heavy elements.
5. Biological Role: Lawrencium is highly radioactive and poses a significant health hazard. It has no known biological role and is toxic to living organisms.

Lawrencium’s synthetic nature, high radioactivity, and limited availability make it primarily of interest to researchers in nuclear science for fundamental studies. Its use is mainly focused on advancing our understanding of nuclear reactions and the behavior of heavy elements. Due to its extreme radioactivity, lawrencium requires strict handling protocols and safety precautions.

Nobelium is a chemical element with the symbol No and atomic number 102. It is a synthetic element and belongs to the actinide series of elements in the periodic table. Nobelium is a highly radioactive metal that is not found naturally on Earth in significant amounts.

Key Characteristics of Nobelium:

1. Radioactivity: Nobelium is an extremely radioactive element, and all of its isotopes are unstable. Its most stable isotope, nobelium-259, has a relatively short half-life of about 58 minutes. Nobelium emits alpha particles, beta particles, and gamma radiation during its radioactive decay.
2. Occurrence: Nobelium is not found naturally on Earth. It is a synthetic element produced in nuclear reactors or through neutron bombardment of other elements, such as curium.
3. Chemical Properties: Nobelium is a reactive element and readily forms compounds with oxygen, halogens, and other elements. It exhibits various oxidation states, with the +2, +3, and +4 states being the most common. Due to its high radioactivity, nobelium is challenging to handle and study.
4. Applications: Due to its extreme radioactivity and limited availability, nobelium has very few practical applications. It is primarily used for scientific research purposes, particularly in the study of nuclear reactions and the behavior of heavy elements.
5. Biological Role: Nobelium is highly radioactive and poses a significant health hazard. It has no known biological role and is toxic to living organisms.

Nobelium’s synthetic nature, high radioactivity, and limited availability make it primarily of interest to researchers in nuclear science for fundamental studies. Its use is mainly focused on advancing our understanding of nuclear reactions and the behavior of heavy elements. Due to its extreme radioactivity, nobelium requires strict handling protocols and safety precautions.

Mendelevium is a chemical element with the symbol Md and atomic number 101. It is a synthetic element and belongs to the actinide series of elements in the periodic table. Mendelevium is a highly radioactive metal that is not found naturally on Earth in significant amounts.

Key Characteristics of Mendelevium:

1. Radioactivity: Mendelevium is an extremely radioactive element, and all of its isotopes are unstable. Its most stable isotope, mendelevium-258, has a relatively short half-life of about 51.5 days. Mendelevium emits alpha particles, beta particles, and gamma radiation during its radioactive decay.
2. Occurrence: Mendelevium is not found naturally on Earth. It is a synthetic element produced in nuclear reactors or through neutron bombardment of other elements, such as einsteinium.
3. Chemical Properties: Mendelevium is a reactive element and readily forms compounds with oxygen, halogens, and other elements. It exhibits various oxidation states, with the +2, +3, and +4 states being the most common. Due to its high radioactivity, mendelevium is challenging to handle and study.
4. Applications: Due to its extreme radioactivity and limited availability, mendelevium has very few practical applications. It is primarily used for scientific research purposes, particularly in the study of nuclear reactions and the behavior of heavy elements.
5. Biological Role: Mendelevium is highly radioactive and poses a significant health hazard. It has no known biological role and is toxic to living organisms.

Mendelevium’s synthetic nature, high radioactivity, and limited availability make it primarily of interest to researchers in nuclear science for fundamental studies. Its use is mainly focused on advancing our understanding of nuclear reactions and the behavior of heavy elements. Due to its extreme radioactivity, mendelevium requires strict handling protocols and safety precautions.

Fermium is a chemical element with the symbol Fm and atomic number 100. It is a synthetic element and belongs to the actinide series of elements in the periodic table. Fermium is a highly radioactive metal that is not found naturally on Earth in significant amounts.

Key Characteristics of Fermium:

1. Radioactivity: Fermium is an extremely radioactive element, and all of its isotopes are unstable. Its most stable isotope, fermium-257, has a relatively short half-life of about 100.5 days. Fermium emits alpha particles, beta particles, and gamma radiation during its radioactive decay.
2. Occurrence: Fermium is not found naturally on Earth. It is a synthetic element produced in nuclear reactors or through neutron bombardment of other elements, such as plutonium.
3. Chemical Properties: Fermium is a reactive element and readily forms compounds with oxygen, halogens, and other elements. It exhibits various oxidation states, with the +2, +3, and +4 states being the most common. Due to its high radioactivity, fermium is challenging to handle and study.
4. Applications: Due to its extreme radioactivity and limited availability, fermium has very few practical applications. It is primarily used for scientific research purposes, particularly in the study of nuclear reactions and the behavior of heavy elements.
5. Biological Role: Fermium is highly radioactive and poses a significant health hazard. It has no known biological role and is toxic to living organisms.

Fermium’s synthetic nature, high radioactivity, and limited availability make it primarily of interest to researchers in nuclear science for fundamental studies. Its use is mainly focused on advancing our understanding of nuclear reactions and the behavior of heavy elements. Due to its extreme radioactivity, fermium requires strict handling protocols and safety precautions.

Einsteinium is a chemical element with the symbol Es and atomic number 99. It is a synthetic element and belongs to the actinide series of elements in the periodic table. Einsteinium is a highly radioactive metal that is not found naturally on Earth in significant amounts.

Key Characteristics of Einsteinium:

1. Radioactivity: Einsteinium is an extremely radioactive element, and all of its isotopes are unstable. Its most stable isotope, einsteinium-252, has a relatively short half-life of about 471.7 days. Einsteinium emits alpha particles, beta particles, and gamma radiation during its radioactive decay.
2. Occurrence: Einsteinium is not found naturally on Earth. It is a synthetic element produced in nuclear reactors by bombarding heavy elements, such as uranium or plutonium, with neutrons.
3. Chemical Properties: Einsteinium is a reactive element and readily forms compounds with oxygen, halogens, and other elements. It exhibits various oxidation states, with the +2, +3, and +4 states being the most common. Due to its high radioactivity, einsteinium is challenging to handle and study.
4. Applications: Due to its extreme radioactivity and limited availability, einsteinium has very few practical applications. It is primarily used for scientific research purposes, particularly in the study of nuclear reactions and the behavior of heavy elements.
5. Biological Role: Einsteinium is highly radioactive and poses a significant health hazard. It has no known biological role and is toxic to living organisms.

Einsteinium’s synthetic nature, high radioactivity, and limited availability make it primarily of interest to researchers in nuclear science for fundamental studies. Its use is mainly focused on advancing our understanding of nuclear reactions and the behavior of heavy elements. Due to its radioactivity, einsteinium requires strict handling protocols and safety precautions.

Californium is a chemical element with the symbol Cf and atomic number 98. It is a synthetic element and belongs to the actinide series of elements in the periodic table. Californium is a highly radioactive metal that is not found naturally on Earth in significant amounts.

Key Characteristics of Californium:

1. Radioactivity: Californium is an extremely radioactive element, and all of its isotopes are unstable. Its most stable isotope, californium-251, has a half-life of about 898 years. Californium emits alpha particles, beta particles, and gamma radiation during its radioactive decay.
2. Occurrence: Californium is not found naturally on Earth. It is a synthetic element produced in nuclear reactors or through neutron bombardment of other elements, such as curium or plutonium.
3. Chemical Properties: Californium is a reactive element and readily forms compounds with oxygen, halogens, and other elements. It exhibits various oxidation states, with the +2, +3, and +4 states being the most common. Due to its high radioactivity, californium is challenging to handle and study.
4. Applications: Californium has very limited practical applications due to its extreme radioactivity and limited availability. It has been used in scientific research, particularly in the study of nuclear reactions and as a neutron source in certain specialized applications, such as nuclear reactors and certain types of radiography.
5. Biological Role: Californium is highly radioactive and poses a significant health hazard. It has no known biological role and is toxic to living organisms.

Californium’s synthetic nature, high radioactivity, and limited availability make it primarily of interest to researchers in nuclear science for fundamental studies. Its use is mainly focused on advancing our understanding of nuclear reactions and as a neutron source in specialized applications. Due to its extreme radioactivity, californium requires strict handling protocols and safety precautions.

Berkelium is a chemical element with the symbol Bk and atomic number 97. It is a synthetic element and belongs to the actinide series of elements in the periodic table. Berkelium is a highly radioactive metal that is not found naturally on Earth in significant amounts.

Key Characteristics of Berkelium:

1. Radioactivity: Berkelium is an extremely radioactive element, and all of its isotopes are unstable. Its most stable isotope, berkelium-247, has a relatively short half-life of about 1,380 years. Berkelium emits alpha particles, beta particles, and gamma radiation during its radioactive decay.
2. Occurrence: Berkelium is not found naturally on Earth. It is a synthetic element produced in nuclear reactors by bombarding heavy elements, such as americium or plutonium, with neutrons.
3. Chemical Properties: Berkelium is a reactive element and readily forms compounds with oxygen, halogens, and other elements. It exhibits various oxidation states, with the +3 and +4 states being the most common. Due to its radioactivity, berkelium is challenging to handle and study.
4. Applications: Due to its high radioactivity and limited availability, berkelium has very few practical applications. It is mainly used for scientific research purposes, particularly in the study of nuclear reactions and the behavior of heavy elements.
5. Biological Role: Berkelium is highly radioactive and poses a significant health hazard. It has no known biological role and is toxic to living organisms.

Berkelium’s synthetic nature, high radioactivity, and limited availability make it primarily of interest to researchers in nuclear science for fundamental studies. Its use is mainly focused on advancing our understanding of nuclear reactions and the behavior of heavy elements. Due to its radioactivity, berkelium requires strict handling protocols and safety precautions.