Correcting units from this physics paper?

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I cannot make units work in this 1973 paper by Hora and need a trustworthy answer.
Hi all,

I've struggled to resolve a units issue in this 1973 paper by Hora:
https://www.academia.edu/23774741/E...tihydrogen_by_lasers_of_very_high_intensities
From the paper:

"
The number [itex]N_p[/itex] of pairs produced in a plasma volume [itex]V[/itex] during a time [itex]\tau[/itex] and a density [itex]n_e[/itex] of electrons is
[tex]N_p=\frac{e^8n_e^2}{\pi\hbar^2m_0^2c^5}V\tau\ln^3\frac{\epsilon_{kin}}{m_0c^2}.[/tex]
"

However, the units do not seem to work out as the LHS is dimensionless.

For what it's worth, I found that Equation (25) is missing one factor of [itex]E_v[/itex]:
[tex]\gamma=\frac{e^2\hbar}{\omega m_0^3c^3}E_v\quad(\mathrm{Incorrect})\quad\Rightarrow\quad\gamma=\frac{e^2\hbar}{\omega m_0^3c^3}E_v^2\quad(\mathrm{Correct})[/tex]

However, I can't tell what factors are missing in this expression. Even in units where [itex]k=1/(4\pi\epsilon_0)=1[/itex], I end up with dimensions of [itex]\mathrm{length}^{-3}[/itex] where I'm expecting dimensionless units.

FWIW, going back to Equation (28):

[tex]\sigma=\frac{e^8}{\pi\hbar^2m_0^2c^6}\ln^3\frac{\epsilon_\mathrm{kin}}{m_0c^2}[/tex]

I get dimensions of [itex]\mathrm{length}^{-2}[/itex], not [itex]\mathrm{length}^2[/itex].

It looks like this is very close to working... please, can someone help me "debug" the units here?

Thanks in advance,
HZ
 
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To fllow you what physical dimension e has in your estimation ?
 

1. What does it mean to correct units in a physics paper?

Correcting units in a physics paper involves ensuring that all measurements, calculations, and results are expressed in consistent and appropriate units according to the International System of Units (SI) or other accepted standards. It also involves verifying that units are algebraically compatible in equations and that conversions between units are accurately performed.

2. How do I identify incorrect units in a physics paper?

To identify incorrect units, first check whether the units used are standard and appropriate for the quantity being measured. Then, ensure that units are consistent throughout the paper, especially in equations where each term must have the same units. Any discrepancies or non-standard units should be flagged for correction.

3. What are the common mistakes made with units in physics papers?

Common mistakes include using non-standard units, mismatching units in equations, incorrect unit conversions, and neglecting to include units in numerical results. Sometimes, errors also arise from typographical mistakes or misunderstandings of unit prefixes (e.g., milli- vs. micro-).

4. How can I convert units correctly in a physics paper?

To convert units correctly, use accurate conversion factors between units. Always ensure that the conversion preserves the physical quantity's dimensionality. Double-check your work by performing the conversion backward to see if you recover the original measurement.

5. What resources are available for help with units in physics?

Resources for help with units include physics textbooks, which often have appendices on units and conversions, online conversion tools, and guidelines published by scientific societies like the International System of Units (SI) or the American Physical Society. Peer consultation and academic advisors can also provide guidance and verification.

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