Astronomy quiz question: monolithic collapse model

Astronomy 210 Quiz 6, fall semester 2011
Cuesta College, San Luis Obispo, CA

According to the monolithic collapse model, there should be no young stars in globular clusters because:
(A) metal-rich stars in the halo have already become metal-poor stars.
(B) there are no metals left in the halo.
(C) dark matter in the halo prevents new stars from forming.
(D) interstellar hydrogen in the halo moved into the disk.

Correct answer: (D).

Since the distribution of interstellar hydrogen in the Milky Way has flattened from spherical to disk-shaped, new star formation occurs only in the disk, and not in the halo, where the first generation stars of the globular clusters are located.

Section 70160
Exam code: quiz06n4Nd
(A) : 11 students
(B) : 4 students
(C) : 2 students
(D) : 9 students

Success level: 40% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.63