# Tag Info

1

I'd simply like to add to physicsphile's answer. The primary source for this question is Konopinski, E. J; C. Marvin; Edward Telle, "Ignition of the Atmosphere with Nuclear Bombs", Los Alamos National Laboratory technical report #LA-602 It shows that the answer to the OP's question is "highly unlikely". It does not prove impossibility. It's an ...

0

Around the 60s, a treaty was signed to ban development of nuclear fusion devices with yield greater than about 50 MT (don't remember exact number), in order to prevent fusion of atmospheric hydrogen, thus the uncontrolled multiplication of the device explosive yield. That was before the Threshold Test Ban Treaty was signed in 1974 and entered into force in ...

8

You might get an order of magnitude estimate as follows. We make the rough assumption that everything ends up in its vessel as a monoatomic ideal gas - actually it will be a plasma, with a thermal energy per mole of $\frac{3}{2}\,R\,T_{final}$, where $T_{final}$ is the thermodynamic temperature of the plasma. Neglecting heats of vaporisation (we assume ...

0

It's easiest to make plasmas with light elements, so the only fusion reactions that are achievable are the hydrogen / helium / lithium ones, which are already pretty well understood. On top of this, a plasma is a chaotic environment with a lot going on. At best you will learn statistical and thermodynamic properties of the underlying interactions. Other ...

0

With the given information, several results are possible: All the kinetic energy is converted into heat and the required temperature for "burning" deuterium is not reached (no star). If the temperature is reached, then the energy released by the deuterium burning might be enough to keep the star from contracting any further. The star might expand a little ...

2

Not only is it possible, it's been going on for decades. As part of a 20 year agreement which came to be known as the 'megatons to megawatts' program, the former-USSR decommissioned some 20,000 nuclear warheads from its military arsenal and recovered 500 tonnes of highly enriched uranium which was combined with 15,000 tonnes of low enriched uranium and sold ...

1

Wow its Dec2014 now. Hello Physics StackExchange again! I have long wondered about why certain elememts nuclei are more unstable the the others. Technetium is one example. It is odd atomic numbered but has no reason to be less stable then other fermionic-like atoms, some heavier but stable like gold. I shall explain further (as I am also unsure) but I will ...

1

An accident which progressed in a somewhat similar manner is the TMI-2 Meltdown. In-vessel inspection at TMI-2 has revealed that an upper cavity existed in which all structural materials had melted and relocated. The first reaction which occurs in the progression of core melt is the formation of Zirconium eutectics. Soon after, structural elements such as ...

0

Is this what you are after: "NIST Atomic Spectra Database". Are you referring to the "Rydberg formula" for "describing the wavelengths of spectral lines of many chemical elements"?

15

In an "ordinary" gas of protons and electrons, nothing would happen - we call that ionized hydrogen! However, when you squeeze, lots of interesting things happen. The first is that the electrons become "degenerate". The Pauli exclusion principle forbids more than two electrons (one spin up the other spin down) from occupying the same momentum eigenstate ...

3

It is instructive to look at chart of isotopes , number of neutrons on the x axis and protons on the y. The stable (black) isotopes diverge from the diagonal, more neutrons are needed to neutralize the coulomb repulsion of the protons, for stability. The main forces are the coulomb force (repulsive) and the strong force (attractive) , but the specific ...

2

Even if the the strong nuclear force is the most powerful force over subatomic distances. The electrostatic force is almost always significant, and, in the case of beta decay (which also involves a transformation of a proton into a neutron), the weak nuclear force is also involved. But the basic answer is yes, you cannot two protons together (Helium 2 ...

0

Just learned this in my chemistry class Okay After beta decay one neutron from the nuclei is "converted" into a proton giving the atom a +1 charge therefore positively charging the atom. Not going to go into the complex electron and an antineutrino creation. Since Beta decay is one process that unstable atoms can use to become more stables beta decay ...

1

According to Grand Unification Theory, protons can decay into electron (even at low energy; just the probability is very low). It doesn't mean you can replace proton with electron.

2

I think there can be confusion around what 'binding energy' and 'mass excess' mean. The Wikipedia entry on Deuterium has links to explanation them, which may clear it up if the following doesn't. IF you could start with isolated protons and neutrons and assemble your own nucleus, the mass (energy) balance of the result would be the sum of the isolated ...

2

Both single beta-decay and double beta-decay may occur with $e^+$ as well as $e^-$. However, in both cases, the emission of $e^-$ is predicted to appear (and in the single beta case, is also observer to appear) in a larger number of processes essentially because it's energetically easier for neutrons to decay to protons plus electrons; than it is for ...

-3

It depends who you ask. A string theorist would answer that string theory is the idea that the point-like particles of elementary particle physics can also be modeled as one-dimensional objects called strings. According to string theory, strings can oscillate in many ways. On distance scales larger than the string radius, each oscillation mode gives rise to ...

11

No. The atoms are protons, electrons and neutrons. The fact that neutrons beta decay into a proton + electron + electron antineutrino does not mean that neutrons are made of a proton and electron and a neutrino.

17

No. The decay products of a certain particle are not equivalent to its constituents. This is evident especially in the context of fundamental particles: quarks can decay into other particles, but that does not mean that a quark is not elementary (see my answer to this question). Nuclei are made of neutrons and protons, which in turn consist of quarks and ...

1

The fast electrons slow down in the cathode, mostly due to interactions with atomic electrons. But hard X-rays are produced mostly due to deflection to large angles in the field of atomic nuclei. Roughly speaking, an atomic electron can stop the projectile electron in a head-on collision, but a nucleus can "reflect" the projectile back, so here the ...

1

The change in velocity of the electron give rise to emission of X-rays. The electrons arrive at the anode with very high velocity and end up at thermal velocities - which must mean they slowed down. Both statements are therefore true.

0

A Human can survive much higher transient over pressures than can buildings. The problem with windows is flying glass. In a lot of terrorist attacks in cities windows being blown in is a major source of casualties. That's why in the UK during WW2 many people had either heavy curtains or tape over the windows.

0

The short and simple answer is no. The more important thing to worry about in nuclear explosions is the heat. If you are close enough to worry about the shock wave, you are likely to be exposed to extreme heat. The center of thermonuclear explosions is well over one million degrees and the fireball from large hydrogen bombs can be more than a mile in ...

2

When a charged particle comes into the vicinity of another, it's path is deflected. It decelerates in one direction, and accelerates in another. All charged particles that are accelerated/decelerated by another charged particle, or a magnetic field, emit radiation. See: Bremsstrahlung. Synchrotron radiation. Cyclotron radiation.

1

We really can't tell very much at all about the presolar epoch by looking at Uranium in the Earth. However much is known for looking at more "pristine" materials from the early solar system. The Sun formed in an interstellar medium containing contributions from lots of different sources and lots of different stars. We know this from the study of presolar ...

3

I can only answer qualitatively: The experiment where the death occurred was on a subcritical mass of plutonium, and reflectors were being used to bring the number of neutrons to the ones required for criticallity. The mean generation time, Λ, is the average time from a neutron emission to a capture that results in fission and l is the the prompt ...

30

Your understanding is pretty much correct and your question quite a natural one. The core did react: the release of energy heated the core and shells quickly, thus changing the neutron capture cross section for the plutonium in the core. A plutonium (or any fissionable) atom's ability to capture a neutron and undergo fission is weakly dependent on ...

2

You're right that in the context of radioactivity, antineutrinos are pretty much only released when a neutron turns into a proton, ${}_0^1n\to {}_1^1p+{}_{-1}^{\;0}e+\bar{\nu}$. They can also be consumed when a proton turns into a neutron and a positron, ${}_1^1p + \bar{\nu}\to {}_0^1n + {}_{1}^{0}e$. There are some other processes that involve ...

0

There are many types of nuclear decay, and many techniques for estimating half-lives. For beta decay of states in spherical nuclei, calculation of decay rates is a classic application of the (spherical) nuclear shell model. For gamma decay, there are generic estimates that are based on the energy and multipolarity of the transition. (The term to google on ...

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