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Radiation is a process in which energetic particles or energetic waves travel through a medium or space. The particles or waves radiate (i.e., travel outward in all directions) from a source.

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Difference between mass energy-absorption vs mass attenuation coefficient

I have never fully grasped the difference between the mass energy-absorption vs mass attenuation coefficients, for use in calculating x-ray / gamma radiation absorption in a material. Hopefully ...
58 views

Do air-crafts fall when exposed to nuclear radiation? [on hold]

I don't have a background in physics. However I wanted to ask a question relevant to the Chernobyl disaster. From what I found online the helicopter that tried to release sand to shut down the fire ...
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So, I already asked a question on the topic, that helped me understand some more. Now, here i find myself blocked again. I don't know how to solve the following problem: In a basement, you notice ...
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Activity and radioactive decay

So, I am pretty new to that concept, which i am learning about in the context of physical chemistry. I am a mathematician, so a physicists approach can be confusing at times. I have two questions : ...
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Energy spectrum of photoneutrons

In "Radiation Detection and Measurement" Knoll considers the production of neutrons by a ($\gamma$, n) reaction such as \begin{align} \gamma + \ ^{2}_{1}\text{H} \rightarrow \ ^{1}_{1}\text{H} + n &...
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How is this dose rate equation derived?

I've been trying to determine how the following equation for dose rate from a gamma point source has been derived, I've seen it in numerous books with no clear explanation for its derivation, ...
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Why is net radiation heat loss so impossibly high in this everyday case?

If a hot object (temperature $T_h$) is radiating energy to cooler surroundings (temperature $T_c$) engineers express the radiation heat loss as: $Q = \sigma \varepsilon (T_h^4 - T_c^4) A$ which is ...
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Cooling by radiation in space [on hold]

Let's say that you have a gram of molten gallium in the vacuum of space just floating about. how fast would It cool back to a solid via radiation?
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Fitting Beta Emission spectrum data according to fermi function

I was trying to fit beta emission spectrum data to the equation $$\tau(E_e) \propto (E_e^2 - m_e^2 c^4)(Q-E_e)^2\frac{E/c}{\sqrt{E_e^2 - m_e^2 c^4}}.$$ However, on making a custom equation in Origin,...
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Do γ gamma photons of pair production potential > 1.022MeV accelerate neutron decay? [duplicate]

If there are/have been studies testing this exact or the general version of this hypothesis, a reference link would be the preferred answer. Experimental phy. Leah Broussard describing current ...
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Why do thermal cameras work at infrared radiation and not at visible one?

From the Wien's law I have computed the Spectral Irradiance of a black body at 1000°C. From different thermal cameras manufacturers web sites, a lot of Thermal Cameras work in the range 6-14 $\mu m$....
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Calculation with gamma constant to find dosis in sievert/hour

This is a serious question as it's related to my work and actual handling of flour-18. (Always behind plenty of shielding). But i'm very curios of the danger without any protection. I'm trying to ...
42 views

Alpha decay and Fermi-Dirac vs Bose-Einstein statistics

This article on wikipedia on alpha decay states: One curiosity is why alpha particles, helium nuclei, should be preferentially emitted as opposed to other particles like a single proton or neutron ...
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Radioactive Decay ($dN/dt = - \lambda N$)

The formula for radioactive decay, $$N = N_0 \ e^{- \lambda t}$$ is derived from the following assumption: $$\frac{dN}{dt} = - \lambda N.$$ I understand an assumption has been made that no external ...
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Spinthariscope with Uranium pottery / marbles instead of Americium

Usually home made zync sulfide spinthariscopes employ Americium 241 from smoke detectors as an alpha radiation source. Uranium glazed pottery (e g. fiestaware) and uranium 'glow in the dark' marbles ...
82 views

Understanding radiation of objects

I am trying to understand Greenhouse effect. I have heard that during the day the earth absorbs heat from the sun and during the night it looses heat in the form of infrared radiation. Does earth ...
31 views

Would it be possible to create a “Vantablack” to absorb outer space radiation?

Looking at this Business Insider article, one of the biggest hurdles of getting humans to Mars is how to reduce the amount of radiation that they are subjected to. Now we do have the Vantablack paint ...
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Mitigation of dead zones when applying circular polarized antenna in shipping containers

I would like to know if I used a circular polarized (RHCP) antenna inside a metal container as show in the configuration below will it reduce the dead zones, as compared to a linear polarized antenna? ...
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Interstellar medium shock heating

How fast would a hypothetical spacecraft need to get to experience significant heating from interaction with the interstellar medium (ISM)? Significant, in this context, means a steady-state ...
61 views

Why gravitational waves can only be generated by a time-varying quadrupole moment of the mass distribution?

The (rather old) source I dispose of "Sexl, Urbantke : Gravitation and Cosmology" describes the radiation of gravitational waves only rather sketchy. So why gravitational waves are only generated by ...
32 views

How to Clearly Define Sample Size in Half-Life Measurements?

I'm curious about how to clearly define the sample size when calculating the half-life of particles. My understanding is that the half life is statistical in nature and that for very small samples, ...
57 views

How do ionizing and non-ionizing radiation interact with each other?

Given an ionizing radiation $X$ and given non-ionizing radiation $Y$, how does this radiation 2 interact with each other? For example I have X-rays (ionizing radiations) and Microwaves (non-...
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Is there any published ratio between the photo peak and the compton continuum as seen on NaI(Tl) 3“x3” at 1460 keV?

As I know from Gamma spectroscopy, there should be a photo peak from a given element that emits a gamma ray, with the possibility of single/double escape, back scatter peak if the energy surpasses the ...
37 views

Why are helium nuclei, electrons and gamma radiation given special names?

Wikipedia article on alpha radiation says Alpha particles were first described in the investigations of radioactivity by Ernest Rutherford in 1899 I can't access the paper containing this ...
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Is there a radiation equivalent in the strong and weak forces?

I know that light is electromagnetic radiation (sourced by accelerating charge) and gravitational waves are gravitational radiation (sourced by accelerating mass). Is there equivalent radiation for ...
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Can beta rays induce radioactivity

I am aware that alpha particle can induce radioactivity. Is it also true for beta and gamma rays?
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Is Inverse Beta Decay a way to “undo” beta decay?

If we consider the beta-minus decay of a radioisotope, we produce an electron and an antineutrino, and a neutron which is converted to a proton. Say we take this same isotope and shoot an ...
124 views

Neutron capture calculation

So, the problem state is: Neutron beam radiates sample A with initial number of atoms $N_0$. With neutron capture nuclei (cores) of A are transitioning to nuclei B (they are just one neutron richer ...
57 views

What if there was no baryon-antibaryon asymmetry in our universe?

We know that the universe goes through different evolutionary phases: radiation, matter and later dark energy epoch. What would happen if there was no baryon-antibaryon asymmetry? How would the ...
269 views

How can beta plus decay be possible?

$\beta +$ decay is where a proton gets turned into a neutron and a positron and a neutrino. However, a neutron is heavier than a proton, so obviously this reaction is endothermic. So then, why does ...