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fab13
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<Moderator's note: Moved from a technical forum and thus no template.>
Suppose that all stars in this galaxy were born in a single major-merger burst event about 10
Gyr ago. From this original burst, I want to compute the fraction of stellar mass still surviving as stars in the
main sequence ? For this, I have got to use a Salpeter IMF, and a star formation range between 0.1 and 120 solar
masses.
What I have done is starting from Salpeter IMF : ##\Phi(m)\text{d}m=\Phi_{0}\,m^{-2.35}##
with ##\Phi_{0}## a constant normalization.
From this, I integrate from ##m_{1}=0.1\,\text{M}_{\odot}## to ##m_{2}=120\,\text{M}_{\odot}##
##N(0.1<m<120) = \int_{0.1}^{120}\,\Phi(m)\,\text{d}m = \Phi_{0}\,\bigg[\dfrac{0.1^{-1.35}-120^{-1.35}}{1.35}\bigg]##
This result depends on the valeur of ##\Phi_{0}## and I don't know how to deal with it in order to get ##N(0.1<m<120)## ?
Moreover, it seems that I have to take into account of the age of the major-merger burst event (10 Gyr).
From these 2 principles, how could I calculate the fraction of stars surviving in the main sequence ?
Any help is wlecome, Regards
Suppose that all stars in this galaxy were born in a single major-merger burst event about 10
Gyr ago. From this original burst, I want to compute the fraction of stellar mass still surviving as stars in the
main sequence ? For this, I have got to use a Salpeter IMF, and a star formation range between 0.1 and 120 solar
masses.
What I have done is starting from Salpeter IMF : ##\Phi(m)\text{d}m=\Phi_{0}\,m^{-2.35}##
with ##\Phi_{0}## a constant normalization.
From this, I integrate from ##m_{1}=0.1\,\text{M}_{\odot}## to ##m_{2}=120\,\text{M}_{\odot}##
##N(0.1<m<120) = \int_{0.1}^{120}\,\Phi(m)\,\text{d}m = \Phi_{0}\,\bigg[\dfrac{0.1^{-1.35}-120^{-1.35}}{1.35}\bigg]##
This result depends on the valeur of ##\Phi_{0}## and I don't know how to deal with it in order to get ##N(0.1<m<120)## ?
Moreover, it seems that I have to take into account of the age of the major-merger burst event (10 Gyr).
From these 2 principles, how could I calculate the fraction of stars surviving in the main sequence ?
Any help is wlecome, Regards
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