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TanX
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Hello everybody! I am TanX. I was reading about neutrons in a gravitational field, which was based on the Grenoble experiment ( Institute Laue - Langevin ) conducted in 2002. I have put a link down here to the research papers below ( Refer to page number 17 in the booklet for the important diagram )
https://www.physi.uni-heidelberg.de/Publications/dipl_krantz.pdf
Q: [/B]The neutrons enter the cavity with a wide range of positive and negative vertical velocities, vz. Once in the cavity, they fly between the mirror below and the absorber above.
The neutron transmission rate N(H) is measured at the detector D ( WHERE H IS THE DISTANCE BETWEEN ABSORBER AND REFLECTOR ) We expect that it increases monotonically with H. Compute the classical rate N(H) which is measured at the detector (D), assuming that neutrons arrive at the cavity with vertical velocity vz at height z being all values of vz and z being equally probable. Give the answer in terms of p, the constant number of neutrons per unit time per unit vertical velocity per unit height that enter the cavity with vertical velocity vzand at height z
Conservation of Energy.
Properties of Elastic collisions
∫(1-x)1/2 dx = {2(1-x)3/2}/ 3
This is probably what I need to use to get to the solution but I have no clue what it means or how it can be used.
3. The Attempt at a Solution [/B]
Okay...Here's my attempt at the solution
So obviously the rate of transmitted neutrons entering at height z is proportional to the range of allowed velocities. Also the given constant (p) can be used.
To find the range of velocities entering at height h
Total energy of neutron at height z = Maximum Potent ( occurs at max height )
(0.5 M vz2) + MgZ ≤ MgH
Which upon solving gives me
-√2g(H-Z) ≤ vz ≤ √2g(H-Z)
So now...
d(N(z))/dz = p {vzmax - vzmin}
⇒ d(N(z))/dz = 2p√2g(H-z)
After this...I tried integrating the above equation and that's where that given expression is useful... and I don't know how to use this. I would be happy if somebody could assist me here.
Any help will be appreciated! Thanks in Advance!
https://www.physi.uni-heidelberg.de/Publications/dipl_krantz.pdf
Homework Statement
Q: [/B]The neutrons enter the cavity with a wide range of positive and negative vertical velocities, vz. Once in the cavity, they fly between the mirror below and the absorber above.
The neutron transmission rate N(H) is measured at the detector D ( WHERE H IS THE DISTANCE BETWEEN ABSORBER AND REFLECTOR ) We expect that it increases monotonically with H. Compute the classical rate N(H) which is measured at the detector (D), assuming that neutrons arrive at the cavity with vertical velocity vz at height z being all values of vz and z being equally probable. Give the answer in terms of p, the constant number of neutrons per unit time per unit vertical velocity per unit height that enter the cavity with vertical velocity vzand at height z
Homework Equations
Conservation of Energy.
Properties of Elastic collisions
∫(1-x)1/2 dx = {2(1-x)3/2}/ 3
This is probably what I need to use to get to the solution but I have no clue what it means or how it can be used.
3. The Attempt at a Solution [/B]
Okay...Here's my attempt at the solution
So obviously the rate of transmitted neutrons entering at height z is proportional to the range of allowed velocities. Also the given constant (p) can be used.
To find the range of velocities entering at height h
Total energy of neutron at height z = Maximum Potent ( occurs at max height )
(0.5 M vz2) + MgZ ≤ MgH
Which upon solving gives me
-√2g(H-Z) ≤ vz ≤ √2g(H-Z)
So now...
d(N(z))/dz = p {vzmax - vzmin}
⇒ d(N(z))/dz = 2p√2g(H-z)
After this...I tried integrating the above equation and that's where that given expression is useful... and I don't know how to use this. I would be happy if somebody could assist me here.
Any help will be appreciated! Thanks in Advance!