Ay 124 Winter 1992:				Assignment #2
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Reading:

	GKK chapter 2; MB chapter 4.

	Bahcall & Soneira (1980; at least the handout),
	and/or Bahcall (1986, ARAA 24, 577).


For Thursday, Jan. 23:

	Read MB chapters 6 and 7.

	Skim through GKK chapters 9 and 10.


A little computational problem, due on Monday, Jan. 27:

    o  Assume the disk luminosity function given by Eq. (1) 
       of Bahcall & Soneira (1980).

    o  Assume that the vertical distribution can be 
       approximated by two exponentials, depending on M(V), 
       as in Fig. 2 of Bahcall & Soneira (1980); approximate 
       it as a step function.

    o  Neglect the interstellar extinction, and the spheroid.

    o  Compute differential and integrated star counts, N(m) 
       and A(m) towards the Galactic pole, down to m(V) = 28.

    o  Compare your results with those of Bahcall & Soneira 
       (1980), and discuss the discrepancies.

	(If you think this is tough, try other directions, 
	and do not neglect the extinction and the spheroid.)