Reaction Rate of a Solar Fusion

In summary, the conversation discusses finding the reaction rate of a star made purely of hydrogen at a temperature of 15MK and density of 150gm/cm^3, with reactions taking place at a distance of 0.25R from the center. The number of protons in the sun's core is calculated using the volume of the sun and the molar mass of hydrogen. The reaction rate data for the H1(P,E+NU)H2 reaction at 15MK is obtained from ORNL, and the next step is to find <σv>, the reaction rate. The equation <σv> = RDensity * NH / Volume is used, but the resulting value appears to be very small. The person asks for clarification
  • #1
Kromboy85
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0

Homework Statement


Find the reaction rate of a star purely of Hydrogen at temperature of 15MK, density of 150gm/cm^3, most of the reactions take place at R0=0.25R. Each reaction released energy of 25MeV



Homework Equations


This is the part I'm lacking. I've got the number of protons in the sun calculated by;
VolSun = (4/3)*pi*(0.25R)^3
Divided that by molar mass of Hydrogen (1) and left with number of moles of Hydrogen, thus Proton in the sun at its core.


The Attempt at a Solution



So from there, I went to ORNL and got the reaction rate data for H1(P,E+NU)H2 reaction
at 15MK which is about RDensity = 50*10^-20 (cm^3*moles^-1*s^-1)

Now, I need to find <σv> which is the reaction rate.

I tried using <σv> = RDensity * NH(Number of moles of Hydrogen) / Volume
Which cancels out all the units and leaves me with s^-1

But when I take that number, multiply by 1.6*10^-19 to account going from MeV to Joules and calculate the power and thus, flux, it comes out to be a very small number which makes me feel like I'm missing something big here.
 
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  • #2
I'm new to this field so please do explain the steps to calculate the reaction rate in as much detail as you can. I'm sure I'll get it.Thank you.
 

1. What is the reaction rate of solar fusion?

The reaction rate of solar fusion refers to the rate at which nuclear fusion reactions occur in the core of the sun. It is measured in units of energy produced per unit time, typically in megawatts.

2. How is the reaction rate of solar fusion determined?

The reaction rate of solar fusion is determined by the temperature, density, and pressure in the sun's core. These factors affect the rate at which hydrogen atoms fuse together to form helium, releasing energy in the process.

3. What factors can affect the reaction rate of solar fusion?

As mentioned, the temperature, density, and pressure in the sun's core are the main factors that affect the reaction rate of solar fusion. Additionally, the composition of elements in the core can also impact the rate of fusion reactions.

4. How does the reaction rate of solar fusion impact the sun's energy output?

The reaction rate of solar fusion directly impacts the sun's energy output. A higher reaction rate means more nuclear fusion reactions are occurring, resulting in a greater amount of energy being produced and released from the sun's core.

5. Can the reaction rate of solar fusion change over time?

Yes, the reaction rate of solar fusion can change over time. The sun's core temperature, density, and pressure can fluctuate, which can affect the rate at which fusion reactions occur. Additionally, changes in the sun's composition or other external factors can also impact the reaction rate of solar fusion.

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