Nuclear physics is the study of the composition, behavior and interaction of atomic nuclei and their constituent parts.
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Does a Photon leave trace in a silicon tracker?
I am having this image from ATLAS Detector.
In gray you can see the ATLAS's Si Tracker.In Green you see the Electromagnetic Callorimeter. In red there is the Hadron Callorimeter and in Blue there ...
6
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2answers
161 views
Is the speed of sound almost as high as the speed of light in neutron stars?
Have you ever wondered about the elastic properties of neutron stars?
Such stars, being immensely dense, in which neutrons are bound together by the strong nuclear force on top of the strong gravity ...
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1answer
75 views
Spin and Parity of $^{17}_8 O$ excited states
$^{17}_8 O$ quoted here has a spin of 5/2 and parity of +1 for the ground state, I agree with this, the unpaired neutron is in the $1d_{1/2}$ state so l = 2, spin = 5/2.
Now I want to figure out the ...
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0answers
69 views
Beta decay for Ar-38, K-38, Cl-38
I want to prove that $^{38}Ar$ is stable with respect to $\beta$ decay, that $^{38}Cl$ decays by $\beta^-$ and that $^{38}K$ decays by $\beta^+$.
I know from Googling that this is true, and I also ...
4
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1answer
54 views
$\alpha$ decay to more than one nuclear state
I do not understand how $\alpha$ decay can be a probabilistic process such that there are multiple products from the decay. For example:
$^{241}\mathrm{Cm}$ decays to the excited states of ...
2
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2answers
210 views
Water-cooled fast neutron reactors
Can anyone explain why fast neutron reactor designs use sodium/lead/salt cooling, instead of water (heavy/light)?
Is that because neutron absorption by water would not allow to break even in fuel ...
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1answer
75 views
Stability of nucleii and $A=5$
Why there is no stable nuclei with
$$A=5$$
in nuclide the chart and so in nature like we know it?
4
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1answer
130 views
Radiation exposure to a child who was briefly in the presence of an adult who had received a 18FDG PET scan
I am a physician who thought she was good at math, but apparently am not as I cannot figure out this mathematical/physics question. (My background is obviously NOT nuclear medicine!) A family friend ...
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1answer
60 views
Is it feasible to convert the energy of gamma-photons from gamma-emitting nuclear isomers into electrical power?
It is known that gamma rays emitted by nuclear isomers, naturally occurring or manufactured, carry huge amounts of energy. Co-60 for example decays into the isomeric state of Ni-60 by $\beta ^-$ ...
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2answers
72 views
Muon production in particle accelerator
PAMELA is a particle accelerator which have two concentric rings, protons are accelerated in the inside ring.
At ISIS muons are produced when a 800 MeV proton beam collides with a graphite ...
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2answers
85 views
Electron mass changes with website
When particles mass can be changed by changing the website, then how to calculate with confidence?
For example:
Google: electron mass = 9.10938 188 × 10$^-31$ kilograms
Wikipedia: electron mass
...
3
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2answers
128 views
How is energy produced in Alpha emission (radioactivity)?
In the above Alpha decay reaction, we get thorium by the alpha decay of uranium with an alpha particle. But we also get energy of amount Q by this process. And according to my course books, this Q ...
4
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1answer
100 views
Why is the Wick contraction in HFB or BCS equal to a single-particle density?
I'm trying to understand how in Hartree-Fock-Bogoliubov
(HFB) or BCS theory we can write a product of creation/annihilation operators as single-particle densities under the guise of "Wick's theorem".
...
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2answers
46 views
Beta particle energy
what does it mean that a beta particle has a 1.6 MeV of energy , does it mean that it can ionize 120000 hydrogen particle with ionization energy of 13.6 MeV ?
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0answers
27 views
Nuclear structure [duplicate]
Possible Duplicate:
Are the protons and neutrons in the nucleus arranged in any particular way?
Isotopes have different numbers of neutrons. Essentially my question is: how does the ...
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1answer
68 views
Combining of iron nuclei
Iron is the most stable single element (I don't know about combinations of elements, but oh well, not applicable to question). Stars go through cycles where they change the materials of their cores, ...
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1answer
48 views
Reflectance and Absorption properties of X-rays
Are there any materials that are mostly "transparent" to x-rays? Such as glass would be to the visible spectrum?
What about materials or surfaces that reflect x-rays? Does most metal reflect x-rays?
...
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1answer
92 views
How is North Korea planning to test a nuclear device underground? [closed]
I am reading the news about North Korea planning to test a nuclear device underground, and while fascinating, I have no idea what this phrase actually means.
Could somebody explain, in absolute ...
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1answer
96 views
Theortical power limit of nuclear bomb
Is there any limits of power or power to mass (or any other) limits for nuclear bombs?
I found this wiki article: Nuclear weapon yield: Yield limits. Is the information provided is correct? If yes, ...
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1answer
47 views
How does a noseblow counter detect alpha radiation?
After working in air fed suits,operatives are required to give samples from their nasal passages by blowing their nose into a tissue,which is then counted in a noseblow counter. How does this work?
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47 views
Photons emitted by radioactive source
Can we calculate the number of photons emitted per second by a radioactive source (gamma) ?
we can take 100g of barium-133 as an example
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1answer
126 views
How do you calculate the equivalent absorbed radiation dose from activity, type of emission, and the energy of the emission?
I have a sample of U-238 of which my Geiger counter detects beta activity at 700 events per second. Based on the counter's efficiency of 98.6% for U-238, the activity would be about 710 becquerels, I ...
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1answer
79 views
Optimal methods for mapping out molecules, atoms and nuclei and their energy levels?
I'm wondering if it would be possible to map out all the different types of molecules, atoms and nuclei and their energy levels on one page (even if in a generalised way)? But perhaps I'm referring to ...
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1answer
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What is pulsed neutron diffraction?
I have tried a google search and checked my condensed matter books but I can't find out what pulsed neutron diffraction is and how it differs from inelastic neutron scattering.
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1answer
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diffrent elements from diffrent elements [closed]
Do we get elements from other elements ?
Somebody said they believed the world was visited by aliens and they made slavs of us and then amde us mine gold for them then they leave us to grow into what ...
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1answer
83 views
What do we do with the byproducts of Nuclear Fusion? [closed]
http://wiki.answers.com/Q/What_are_the_byproducts_of_nuclear_fusion
So I quickly googled the byproducts of fusion and got the above link.
It looks to me that you'll be left with He atoms. So what ...
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1answer
431 views
Explanation of energy levels in molecules, atoms, nuclei and their relationship
Why are the energy levels of molecules, the atoms that form them and the nuclei inside the atoms considered separately? Or phrased in a different way- what is it that makes their energy levels so ...
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2answers
68 views
Was the early Earth radioactive?
I've been reading of the (surprising) fact we are uncertain on whether there is nuclear fission in the center of the Earth or not (yet we know so much detail on structures at the other end of the ...
5
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3answers
239 views
Do some half-lives change over time?
I was recently doing some physics tuition on radioactivity and the student claimed her chemistry teacher had said that radioactive substances can be grouped into two divisions: those whose half-life ...
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0answers
28 views
Energy of split of nucleus [closed]
How much energy must be supplied to the nucleus of lithium isotope Li-7 (3 protons, 4 neutrons) to separate them into individual protons and neutrons? The atomic weight of lithium is $1.1524 \times ...
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1answer
92 views
A strange particle, $X$, decays in the following way: $X → π^– + p$. State what interaction is involved in this decay
A strange particle, $X$, decays in the following way: $X → π^– + p$. State what interaction is involved in this decay.
I know the answer to be weak interaction, but why is it weak interaction? What ...
9
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2answers
876 views
Pictures of nuclear explosions some milli/nano seconds after detonation
Where I can find photos of nuclear explosions just after detonation (before 5-10 ms, the shorter the better)?
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1answer
91 views
Is $E=mc^2$ reserved to nuclear physics?
I was wondering, while putting a log in my fireplace, how much energy the piece of wood would give. The most famous formula poped into my head: $E=m \cdot c ^ 2$!
Is this formula applicable to a ...
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0answers
49 views
Properties of spilled spent nuclear fuel pellets
Can someone please explain to me the physics of a pile of spilled nuclear fuel pellets on the floor of a spent fuel pool? Specifically, what can we expect in terms of heat and radioactivity releases, ...
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1answer
131 views
Is man-made Carbon Fusion possible?
In a type Ia Supernova, the carbon accumulated in the earlier stages of a stars death fissues to create even heavier elements. Could this be used by humans aswell? Is it theoretically possible to ...
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3answers
788 views
Nuclear fusion: what causes this “resonance” peak?
Can anyone explain why the $^{11}\mathrm{B}\mathrm{H}$ fusion cross-section has a peak near 150 keV, and why $\mathrm{D}\mathrm{D}$ and $\mathrm{D}\mathrm{T}$ have no such sharp peaks?
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1answer
61 views
Which pion is mediator in nucleon-nucleon interaction
In nucleon-nucleon interactions of n-n, p-p, n-p how do you determine which pion is the mediator?
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1answer
82 views
Estimation nuclear force between proton and neutron in deuteron
Is there an estimation of nuclear force between proton and neutron in deuteron to say What is the strong nuclear force between them?
1N?
10N?
100N?
1000N?
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1answer
97 views
About Efimov States and Halo-Nuclei
I read that
Halo nuclei could be seen as special Efimov states, depending on the subtle definitions. (The last sentence in the second to last paragraph of this Wikipedia article.)
This does ...
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1answer
105 views
Direct nuclear reactions problems [closed]
can anyone explain Multi-step nuclear reactions in terms of direct nuclear reactions .
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1answer
91 views
Direct nuclear reaction in nuclear physics
Time taken to occur a direct nuclear reaction is very low $10^{-22}$sec . I want to know the Importance of direct nuclear reactions.
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1answer
218 views
Why isn't Hydrogen's electron pulled into the nucleus? [duplicate]
Possible Duplicate:
Why do electrons occupy the space around nuclei, and not collide with them?
Why don’t electrons crash into the nuclei they “orbit”?
From what I learned in chemistry, ...
3
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1answer
58 views
The synthesis of $^{254}\text{No}$
How is $^{254}\text{No}$ synthesised?
Could you explain the reaction where it is preceded by $^{208}\text{Pb}(^{48}\text{Ca}, 2\text{n})$?
References to articles are well enough—I was somehow unable ...
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0answers
317 views
Is there any reproducible tested evidence for Ni-H cold fusion?
The main replications of cold fusion, the ones that are beyond reproach, used Pd/d as the system. But commercial developers have often claim to use Ni-H to achieve similar effects. The claims include ...
4
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1answer
158 views
Americium battery
I was curious about a radioactive decay battery.
My thought was to place an americium source from a smoke detector in a vacuum sealed borosilicate glass vessel. The Americium source would be "aimed" ...
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0answers
281 views
Why is the binding energy per nucleon not zero for hydrogen atom?
The lone proton has not to be worked on against any electrostatic force. So where does the energy come from? What is mass defect for a hydrogen nucleus?
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1answer
104 views
Is there a good summary of all nuclear fusion approaches?
I am pretty sure, that during last 60 years of well-funded research a lot of ideas on nuclear fusion were already tried and ruled out.
Is there some summary describing all of them and why they ...
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1answer
69 views
Does the strong (nuclear) force ever contribute to decay?
Does the strong (nuclear) force ever contribute to decay ?
Or is the weak nuclear force the only decaying force ?
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690 views
Why is technetium unstable?
Is there a simple account of why technetium is unstable?
From the Isotopes section of Wikipedia's article on Technetium:
Technetium, with atomic number (denoted Z) 43, is the lowest-numbered ...
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Why are synthetic elements unstable?
So far 20 synthetic elements have been synthesized. All are unstable, decaying with half-lives between years and milliseconds.
Why is that?
