Bh and atomic number 107
βohrium is a synthetic chemical element; it has symbol Bh and atomic number 107. It is named after Danish physicist Niels Bohr. As a synthetic element, it can be created in particle accelerators but is not found in nature.
All known isotopes of βohrium are highly radioactive; the most stable known isotope is 270Bh with a half-life of approximately 2.4 minutes, though the unconfirmed 278Bh may have a longer half-life of about 11.5 minutes.
Understanding the quadratic formula inside particle acceleration it's necessary to learn how to solve the quadratic equations, in the formulas of math. If you have a general quadratic equation like this:
ax²+ bx + c = 0
Then the formula will help you find the roots of a quadratic equation, i.e. the values of a where this equation is solved.
The quadratic formula, step 1
First we need to identify the values for a, b, and c (the coefficients). First step, make sure the equation in the format from above, ax²+ bx + c = 0:
x² + 4x — 21 = 0
ὰ is the coefficient in front of x², so here ą = 1 (note that a can't equal 0 -- the x² is what makes it a quadratic).
β is the coefficient in front of the x, so here b = 4.
Ç is the constant, or the term without any x next to it, so here c = -21.
The quadratic formula, step 2
Then we plug ὰ, β, and Ͼ into the formula
To understanding this proper we need to investigate in the quadratic formula, inside the Period table. In the periodic table, Bohrium has symbol Bh and atomic number 107. it is a d-block transactinide element. It is a member of the 7th period and belongs to the group 7 elements as the fifth member of the 6d series of transition metals.
Chemistry experiments have confirmed that bohrium behaves as the heavier homologue to rhenium in group 7. The chemical properties of bohrium are characterized only partly, but they compare well with the chemistry of the other group 7 elements.
As we have plug ὰ, β, and Ͼ into the formula:
If we solving the quadratic formula it looks like:Therefore x = 3 or x = −7.
What does the solution tell us? The two solutions are the x-intercepts of the equation, i.e. where the curve crosses the x-axis.
The quadratic formula, step 3
The equation x² + 3x - 4 = 0 witch means: a Nucleus is created out of the blue. Just Boehm!! A superheavy atomic nucleus is created in a nuclear reaction that combines two other nuclei of unequal size into one; roughly, the more unequal the two nuclei in terms of mass, the greater the possibility that the two react.
Simply declared; 5 + 2 = 7.
The material made of the heavier nuclei is made into a target, which is then bombarded by the beam of lighter nuclei. Two nuclei can only fuse into one if they approach each other closely enough; normally, nuclei (all positively charged) repel each other due to electrostatic repulsion.
The strong interaction can overcome this repulsion but only within a very short distance from a nucleus; beam nuclei are thus greatly accelerated in order to make such repulsion insignificant compared to the velocity of the beam nucleus.
The energy applied to the beam nuclei to accelerate them can cause them to reach speeds as high as one-tenth of the speed of light. However, if too much energy is applied, the beam nucleus can fall apart.
Coming close enough alone is not enough for two nuclei to fuse: when two nuclei approach each other, they usually remain together for approximately 10−20 seconds and then part ways (not necessarily in the same composition as before the reaction) rather than form a single nucleus.
This happens because during the attempted formation of a single nucleus, electrostatic repulsion tears apart the nucleus that is being formed.
The quadratic formula, step 4
Each pair of a target and a beam is characterized by its cross section—the probability that fusion will occur if two nuclei approach one another expressed in terms of the transverse area that the incident particle must hit in order for the fusion to occur. Some people have this quadratic formula on there doorstep hanging.
2π ~ C -T = Μµ + ß3 ~ 19
To understanding of this equitation, here is the solutions to the quadratic formula as it intercepts with x = − 4 and x = − 1.
This fusion may occur as a result of the quantum effect in which nuclei can tunnel through electrostatic repulsion. If the two nuclei can stay close for past that phase, multiple nuclear interactions result in redistribution of energy and an energy equilibrium.
On the other side of the spectrum we could youse the left handed quadratic formula as it is written on a formula with 3x² + 6x = − 10.
The resulting merger is an excited state—termed a compound nucleus—and thus it is very unstable. To reach a more stable state, the temporary merger may fission without formation of a more stable nucleus. Alternatively, the compound nucleus may eject a few neutrons, which would carry away the excitation energy; if the latter is not sufficient for a neutron expulsion, the merger would produce a gamma ray.
This happens in approximately 10−16 seconds after the initial nuclear collision and results in creation of a more stable nucleus. This value was chosen as an estimate of how long it takes a nucleus to acquire its outer electrons seen in this formula;
The definition by the IUPAC/IUPAP Joint Working Party (JWP) states that a chemical element can only be recognized as discovered if a nucleus of it has not decayed within 10−14 seconds.
Decay and detection
The beam passes through the target and reaches the next chamber, the separator; if a new nucleus is produced, it is carried with this beam. In the separator, the newly produced nucleus is separated from other nuclides (that of the original beam and any other reaction products) and transferred to a surface-barrier detector, which stops the nucleus.
The exact location of the upcoming impact on the detector is marked; also marked are its energy and the time of the arrival. The transfer takes about 10−6 seconds; in order to be detected, the nucleus must survive this long. The nucleus is recorded again once its decay is registered, and the location, the energy, and the time of the decay are measured.
Stability of a nucleus is provided by the strong interaction. However, its range is very short; as nuclei become larger, its influence on the outermost nucleons (protons and neutrons) weakens. At the same time, the nucleus is torn apart by electrostatic repulsion between protons, and its range is not limited.
Total binding energy provided by the strong interaction increases linearly with the number of nucleons, whereas electrostatic repulsion increases with the square of the atomic number, i.e. the latter grows faster and becomes increasingly important for heavy and superheavy nuclei.
Superheavy nuclei are thus theoretically predicted and have so far been observed to predominantly decay via decay modes that are caused by such repulsion: alpha decay and spontaneous fission.
Almost all alpha emitters have over 210 nucleons, and the lightest nuclide primarily undergoing spontaneous fission has 238. In both decay modes, nuclei are inhibited from decaying by corresponding energy barriers for each mode, but they can be tunnelled through.
Scheme of an apparatus for creation of superheavy elements, based on the Dubna Gas-Filled Recoil Separator set up in the Flerov Laboratory of Nuclear Reactions in JINR. The trajectory within the detector and the beam focusing apparatus changes because of a dipole magnet in the former and quadrupole magnets in the
latter.
Alpha particles are commonly produced in radioactive decays because mass of an alpha particle per nucleon is small enough to leave some energy for the alpha particle to be used as kinetic energy to leave the nucleus.
Spontaneous fission is caused by electrostatic repulsion tearing the nucleus apart and produces various nuclei in different instances of identical nuclei fissioning. As the atomic number increases, spontaneous fission rapidly becomes more important.
Spontaneous fission partial half-lives decrease by 23 orders of magnitude from uranium (element 92) to nobelium (element 102), and by 30 orders of magnitude from thorium (element 90) to fermium (element 100).
The earlier liquid drop model thus suggested that spontaneous fission would occur nearly instantly due to disappearance of the fission barrier for nuclei with about 280 nucleons.
The later nuclear shell model suggested that nuclei with about 300 nucleons would form an island of stability in which nuclei will be more resistant to spontaneous fission and will primarily undergo alpha decay with longer half-lives.
Subsequent discoveries suggested that the predicted island might be further than originally anticipated; they also showed that nuclei intermediate between the long-lived actinides and the predicted island are deformed, and gain additional stability from shell effects.
Experiments on lighter superheavy nuclei, as well as those closer to the expected island, have shown greater than previously anticipated stability against spontaneous fission, showing the importance of shell effects on nuclei.
Alpha decays are registered by the emitted alpha particles, and the decay products are easy to determine before the actual decay; if such a decay or a series of consecutive decays produces a known nucleus, the original product of a reaction can be easily determined. (That all decays within a decay chain were indeed related to each other is established by the location of these decays, which must be in the same place.)
The known nucleus can be recognized by the specific characteristics of decay it undergoes such as decay energy (or more specifically, the kinetic energy of the emitted particle). Spontaneous fission, however, produces various nuclei as products, so the original nuclide cannot be determined from its daughters.
The information available to physicists aiming to synthesize a superheavy element is thus the information collected at the detectors: location, energy, and time of arrival of a particle to the detector, and those of its decay.
The physicists analyze this data and seek to conclude that it was indeed caused by a new element and could not have been caused by a different nuclide than the one claimed. Often, provided data is insufficient for a conclusion that a new element was definitely created and there is no other explanation for the observed effects; errors in interpreting data have been made.
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