Concept explainers
(a)
The radius of a x-ray source orbit, in kilometer, by assuming the radius of its orbit as a circle. Given that the orbital period of a binary system containing A0620-00 is 0.32 days and the radial velocity of x-ray source peaks at 457km/s as reveled by Doppler shift measurement.
(a)
Answer to Problem 38Q
Solution:
Explanation of Solution
Given data:
An orbital period of a binary system containing A0620-00 is 0.32 days and the radial velocity of x-ray source peaks at 457km/s as reveled by Doppler shift measurement.
Formula used:
Write the expression for the relationship between speed time and distance:
Here,
Explanation:
As the orbital period
Convert orbital period of 0.32 days in seconds.
Calculate radius of x-ray source orbit.
Assuming that the orbit is circular in radius
Refer to the expression for the relationship between speed time and distance:
Substitute
Substitute
Conclusion:
Hence, the radius of x-ray source orbit is
(b)
The mass of x ray source, which is at least 3.1 times the mass of the Sun, by Newton’s form of Kepler’s third law. Given that the orbital period of a binary system containing A0620-00 is 0.32 days and the radial velocity of x-ray source peaks at 457km/s as reveled by Doppler shift measurement. Also, assume that the mass of K5V, a visible star, is negligible as compared to that of visible star.
(b)
Answer to Problem 38Q
Solution:
Explanation of Solution
Given data:
An orbital period of a binary system containing A0620-00 is 0.32 days and the radial velocity of x-ray source peaks at 457km/s as reveled by Doppler shift measurement.
Formula used:
Write the expression for Kepler’s third law:
Here,
Explanation:
As the orbital period of binary system containing A0620-00 is 0.32 days.
Convert orbital period of 0.32 days in years.
From part (a) of the question, orbital radius is
Convert orbital radius
Refer to the expression for Kepler’s third law.
Substitute
So, the total mass of x ray source binary system is
Conclusion:
Hence, the total mass of x ray source is
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Chapter 21 Solutions
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