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1. ### A Polaron transformation

I'm trying to understand the so-called polaron transformation as frequently encountered in quantum optics. Take the following paper as example: "Quantum dot cavity-QED in the presence of strong electron-phonon interactions" by I. Wilson-Rae and A. Imamoğlu. We have the spin-phonon model with...

8. ### What will the phasor diagram of this LCR circuit looks like?

I know the current of capacitor and inductor must be parallel but pointing in opposite direction due to the fact they are connected in parallel thus having same voltage (please see attached screenshots). The current of resistor will simply be the sum of these two vectors, but what about its...
9. ### I Confusion on binding energy and ionization energy.

For a single electron system, it's binding energy would just be -RZ2/n2 (where R = 13.606(eV) ). But when we're talking about multielectron system, it's binding energy would become -RZeff2/n2 (since there will be shielding effect due to the inner elecrons, where we need to figure out the Zeff...
10. ### I Confusion on binding energy and ionization energy.

1) I know that the binding energy is the energy that holds a nucleus together ( which equals to the mass defect E = mc2 ). But what does it mean when we are talking about binding energy of an electron ( eg. binding energy = -Z2R/n2 ? ). Some website saying that " binding energy = - ionization...
11. ### Observing galaxies: area of sky would I need to survey

thank you very much, you are very helpful
12. ### Observing galaxies: area of sky would I need to survey

I think that would be (volume I need to observe) / (total sphere volume) = (10000) / (4188790) = 2.39⋅10-3
13. ### Observing galaxies: area of sky would I need to survey

Thank you for the quick reply, the total volume of the sphere is 4188790 Mpc3 ("which indicates the volume of sky I could possibly observed is 4/3⋅π⋅d3 = 4188790 Mpc3") and the volume I need to view is 10000Mpc3 ("thus V=10000Mpc3, which is the volume I need to observed to find 100...
14. ### Observing galaxies: area of sky would I need to survey

How can I find solid angle relative to the 10000MPc3?
15. ### Observing galaxies: area of sky would I need to survey

Homework Statement Given that there are 10-2 Ellipticals per Mpc3 and my garden telescope can reach to 14 mag. How large an area of sky would I need to survey to find 100 Elliptical galaxies ? (assume the typical absolute magnitude for an Elliptical galaxy is -21 mag). Homework Equations...
16. ### About initial mass function and mean mass in stellar cluster

yess I'm really sorry I've forgot to put another M in the second equation! correction: to find mass occupied by the starts in the range x and y: fM = ∫xy M-7/3 M dM / ∫0.120 M-7/3 M dM
17. ### About initial mass function and mean mass in stellar cluster

Homework Statement Assuming a Salpeter IMF with upper and lower mass limits of 0.1 and 20 M⊙ respectively, calculate: (i) the mass point at which half the mass formed in a stellar cluster lies in more massive systems and half in less massive systems. ii) the mass point at which half the...

I did write : To find the angular momentum of the whole rigid body, summing all the tiny pieces, we have : ∑ L = ∑ ri mi ri ωi Since ω is constant everywhere, we then have : ∑ L = ω ∑ mi ri2 ** Note that the ω here does not have a subscript. ** Let's consider the following scenario : If the...