Tagged Questions
1
vote
1answer
131 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 ...
3
votes
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 ...
3
votes
1answer
121 views
How do people get the proton number for each element from experiment?
How did people determine the proton number for each element from experiment in each decade of 20th century?
3
votes
2answers
143 views
Pressures Necessary for Carbon Detonation
Carbon detonation is a characteristic event of Type 1a Supernova (EDIT: where an accreting white dwarf near the Chandrashankar limit of 1.4 solar masses explodes), an extremely important standard ...
4
votes
3answers
181 views
Could we prove that neutrinos have mass by measuring their gravitational signature?
It is now said that neutrinos have mass. If an object has mass then it also emits a gravitational field. I appreciate the neutrinos mass is predicted to be small, but as there are so many produced ...
2
votes
1answer
123 views
How was Be-8's Half-Life of 7E-17 Second Determined?
Radionuclides occur with half-lives in a vast range of over 37 magnitudes as listed in this site. In question 7584, Lubos Motl explained how Gyr half-lives were determined. This method doesn't appear ...
10
votes
4answers
385 views
How do we know that the nucleus isn't a quark-gluon plasma?
The standard picture of the nucleus of atom is that is several distinct nucleons, which themselves are composed of quarks. However, it seems to me like a much simpler picture is that the nucleus is ...
7
votes
2answers
1k views
How do we know that some radioactive materials have a half life of millions or even billions of years?
If a radioactive material takes a very long time to decay, how is its half life measured or calculated? Do we have to actually observe the radioactive material for a very long time to extrapolate its ...
3
votes
1answer
211 views
PNMR, Pulsed Nuclear Magnetic Resonance, Experiment
I am writing a lab report for class on PNMR experiment that we did. How come in this experiment we don't worry about the electron spins in our sample? Aren't the electrons affected by the PNMR machine ...
1
vote
1answer
145 views
Are there notable cases of anomalies in the mass-decay rate relationship?
As a general rule of thumb, massive particles (both composite and fundamental) tend to decay rapidly through the weak force, while less massive particles tend to be more stable. Hence, taus are ...
