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تسجيل مستخدم جديدProperties of the cluster population of NGC 1566 and their implications
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تأليف
Katherine Hollyhead
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We present results of a photometric study into the cluster population of NGC 1566, a nearby grand design spiral galaxy, sampled out to a Galactocentric radius of $approx 5.5$ kpc. The shape of the mass-limited age distribution shows negligible variation with radial distance from the centre of the galaxy, and demonstrates three separate sections, with a steep beginning, flat middle and steep end. The luminosity function can be approximated by a power law at lower luminosities with evidence of a truncation at higher luminosity. The power law section of the luminosity function of the galaxy is best fitted by an index $approx -2$, in agreement with other studies, and is found to agree with a model luminosity function, which uses an underlying Schechter mass function. The recovered power law slope of the mass distribution shows a slight steepening as a function of galactocentric distance, but this is within error estimates. It also displays a possible truncation at the high mass end. Additionally, the cluster formation efficiency ($Gamma$) and the specific U-band luminosity of clusters ($T_L(U)$) are calculated for NGC 1566 and are consistent with values for similar galaxies. A difference in NGC 1566, however, is that the fairly high star formation rate is in contrast with a low $Sigma_{SFR}$ and $Gamma$, indicating that $Gamma$ can only be said to depend strongly on $Sigma_{SFR}$, not the star formation rate.
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