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تسجيل مستخدم جديدHigh-resolution UKIRT observations of circumnuclear star formation in M100
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Stuart D. Ryder
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We present high-resolution, near-infrared imaging of the circumnuclear region of the barred spiral galaxy M100 (=NGC 4321), accompanied by near-infrared spectroscopy. We identify a total of 43 distinct regions in the K-band image, and determine magnitudes and colours for 41 of them. By comparison with other near-infrared maps we also derive colour excesses and K-band extinctions for the knots. Combining the imaging and spectroscopic results, we conclude that the knots are the result of bursts of star formation within the last 15-25 Myr. We discuss the implications of these new results for our dynamical and evolutionary understanding of this galaxy.
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