High-resolution UKIRT observations of circumnuclear star formation in M100
نویسندگان
چکیده
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.
منابع مشابه
Resolving Circumnuclear Star Formation in M100 with Image Stabilisation at UKIRT
Near-infrared (JHK) images of the nucleus of the barred spiral galaxy M100 (NGC 4321) have been obtained using a high-bandwidth tip-tilt secondary and fast guider system on the 3.8m United Kingdom Infrared Telescope (UKIRT). The resulting images, with a resolution of 0: 00 34 at K, reveal for the rst time a host of compact \knots", which appear to be the result of a recent burst (or bursts) of ...
متن کاملResolving Circumnuclear Star Formation in M with Image Stabilisation at UKIRT
Near infrared JHK images of the nucleus of the barred spiral galaxy M NGC have been obtained using a high bandwidth tip tilt secondary and fast guider system on the m United Kingdom Infrared Telescope UKIRT The resulting images with a resolution of at K reveal for the rst time a host of compact knots which appear to be the result of a recent burst or bursts of star formation Con rmation of th...
متن کاملCircumnuclear starbursts in barred galaxies
I discuss new observations of circumnuclear regions in barred galaxies, both of their kinematics and their near-infrared (NIR) morphology. New kinematic observations of M100 con rm that (1) the inner bar-like feature detected before in this galaxy is in fact a continuation of the large-scale stellar bar; and (2) the spiral arm-like sites of star formation in the circumnuclear zone are manifesta...
متن کاملNear-infrared spectroscopy of the circumnuclear star formation regions in M100: Evidence for sequential triggering
We present low resolution (R ∼ 450) K-band spectroscopy for 16 of the 43 circumnuclear star-forming knots in M100 identified by Ryder & Knapen (1999). We compare our measurements of equivalent widths for the Brγ emission line and CO 2.29 μm absorption band in each knot with the predictions of starburst models from the literature, and derive ages and burst parameters for the knots. The majority ...
متن کاملKinematics in the Starbursting Circumnuclear Region of M100
We have obtained integral-field spectroscopic data, using the SAURON instrument, of the bar and starbursting circumnuclear region in the barred spiral galaxy M100. From our data we have derived kinematic maps of the mean velocity and velocity dispersion of the stars and the gas, which we present here. We have also produced maps of the total, [Oiii], and Hβ intensity. The gas velocity field show...
متن کامل