Abstract
An attempt has been made to derive a version of the virial integral that would describe average properties of the interstellar medium (ISM) at the scale ~1 kpc. The role of the dark matter is accounted for only via its effect on the global gravitational potential. It is suggested to eliminate the (large) contribution of stellar matter by introducing "exclusion zones" surrounding stars. Such an approach leads to the appearance of several types of additional surface integrals in the general expression. Their contribution depends on the rate of energy and matter exchange between the stars and ISM. If this exchange is weak, one can obtain a desired virial integral for the ISM. However, the presence of intermittent large-scale energetic events significantly constrains the applicability of the virial theorem. If valid, the derived virial integral for the ISM is dominated by cold molecular/atomic clouds, with only a minor contribution from the global magnetic field and low-density warm part. The main message of our study is that one has to be very cautious in applying the virial theorem to the ISM at large scales (of the order of thickness of the spiral arm).
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
