Shardha Jogee et al. 2002 ApJ 575 156 doi:10.1086/341196
Shardha Jogee1, Isaac Shlosman2,8,9, Seppo Laine3, Peter Englmaier4, Johan H. Knapen5,6, Nick Scoville1 and Christine D. Wilson7
Show affiliationsThrough observations and modeling, we demonstrate how the recently discovered large-scale bar in NGC 5248 generates spiral structure that extends from 10 kpc down to 100 pc, fuels star formation on progressively smaller scales, and drives disk evolution. Deep inside the bar, two massive molecular spirals cover nearly 180° in azimuth, show streaming motions of 20-40 km s-1, and feed a starburst ring of super-star clusters at 375 pc. They also connect to two narrow K-band spirals that delineate the UV bright star clusters in the ring. The data suggest that the K-band spirals are young, and the starburst has been triggered by a bar-driven spiral density wave (SDW). The latter may even have propagated closer to the center where a second Hα ring and a dust spiral are found. The molecular and Hubble Space Telescope data support a scenario where stellar winds and supernovae efficiently clear out gas from dense star-forming regions on timescales less than a few Myr. We have investigated the properties of massive CO spirals within the framework of bar-driven SDWs, incorporating the effect of gas self-gravity. We find good agreement between the model predictions and the observed morphology, kinematics, and pitch angle of the spirals. This combination of observations and modeling provides the best evidence to date for a strong dynamical coupling between the nuclear region and the surrounding disk. It also confirms that a low central mass concentration, which may be common in late-type galaxies, is particularly favorable to the propagation of a bar-driven gaseous SDW deep into the central region of the galaxy, whereas a large central mass concentration favors other processes, such as the formation and decoupling of nuclear bars.
galaxies: evolution; galaxies: individual (NGC 5248); galaxies: ISM; galaxies: kinematics and dynamics; galaxies: starburst; galaxies: structure
Issue 1 (2002 August 10)
Received 2002 February 13, accepted for publication 2002 April 12
Shardha Jogee et al. 2002 ApJ 575 156
R. K. Honeycutt and J. W. Robertson 1998 The Astronomical Journal 116 1961
Mark Lacy et al. 2003 The Astronomical Journal 126 2230
Arthur M. Wolfe et al. 2003 ApJ 593 235
Mikhail V Chester and Arpad Horvath 2009 Environ. Res. Lett. 4 024008
Jonathan P. Williams and Philip C. Myers 1999 ApJ 518 L37
Kazushi Sakamoto et al. 1999 ApJS 124 403
Abhijit J Chaudhari et al 2005 Phys. Med. Biol. 50 5421
A E Farrell and A R Brandt 2006 Environ. Res. Lett. 1 014004
R Wehlitz et al 1993 J. Phys. B: At. Mol. Opt. Phys. 26 L783