A steady beam of 13.2 eV electrons with a current I=10^-1 mA isdirected into a gas of H atoms which has a number density n=10^10atoms/cm^3. Assume the gas target is t=1cm thick, and that theexcitation cross section per atom for H is sigma=2X10^-16cm^2.
a)what fraction of a volume of 1 cm^3 coule be occupied by excitedatoms?
b)if the excitation rate is I/e, with units of (#/second), use youranswer to part a to estimate how many atoms can be excited persecond.
c)what is the maximum quantum number for H levels excited by theelectrons?
d)assume that all levels with n<n(max) are equally excited, howmany different photon wavelengths will be emitted by the excitedgas?
e)how many different final energies (after a collision) would theexciting electrons have?
A steady beam of 13.2 eV electrons with a current I=10^-1 mA isdirected into a gas of H atoms which has a number density n=10^10atoms/cm^3. Assume the gas target is t=1cm thick, and that theexcitation cross section per atom for H is sigma=2X10^-16cm^2.
a)what fraction of a volume of 1 cm^3 coule be occupied by excitedatoms?
b)if the excitation rate is I/e, with units of (#/second), use youranswer to part a to estimate how many atoms can be excited persecond.
c)what is the maximum quantum number for H levels excited by theelectrons?
d)assume that all levels with n<n(max) are equally excited, howmany different photon wavelengths will be emitted by the excitedgas?
e)how many different final energies (after a collision) would theexciting electrons have?
