Powerful H$_2$ Emission and Star Formation on the Interacting Galaxy System Arp 143: Observations with Spitzer and GALEX TeX Export

@article{citeulike:3739492, abstract = {We present new mid-infrared (\$5 - 35\mu\$m) and ultraviolet (1539 -- 2316 \AA) observations of the interacting galaxy system Arp 143 (NGC 2444/2445) from the Spitzer Space Telescope and GALEX. In this system, the central nucleus of NGC 2445 is surrounded by knots of massive star-formation in a ring-like structure. We find unusually strong emission from warm H\$\_2\$ associated with an expanding shock wave between the nucleus and the western knots. At this ridge, the flux ratio between H\$\_2\$ and PAH emission is nearly ten times higher than in the nucleus. Arp 143 is one of the most extreme cases known in that regard. From our multi-wavelength data we derive a narrow age range of the star-forming knots between 2 Myr and 7.5 Myr, suggesting that the ring of knots was formed almost simultaneously in response to the shock wave traced by the H\$\_2\$ emission. However, the knots can be further subdivided in two age groups: those with an age of 2--4 Myr (knots A, C, E, and F), which are associated with \$8\mu\$m emission from PAHs, and those with an age of 7-8 Myr (knots D and G), which show little or no \$8\mu\$m emission shells surrounding them. We attribute this finding to an ageing effect of the massive clusters which, after about 6 Myr, no longer excite the PAHs surrounding the knots.}, archivePrefix = {arXiv}, author = {Beir\&\#xe3;o, P. and Appleton, P. N. and Brandl, B. R. and Seibert, M. and Jarrett, T. and Houck, J. R.}, citeulike-article-id = {3739492}, citeulike-linkout-0 = {http://arxiv.org/abs/0812.0450}, citeulike-linkout-1 = {http://arxiv.org/pdf/0812.0450}, day = {2}, eprint = {0812.0450}, keywords = {arp143, galaxies, galex, interacting, spitzer}, month = {Dec}, posted-at = {2008-12-07 02:04:21}, priority = {2}, title = {Powerful H\$\_2\$ Emission and Star Formation on the Interacting Galaxy System Arp 143: Observations with Spitzer and GALEX}, url = {http://arxiv.org/abs/0812.0450}, year = {2008} }

TY - JOUR ID - citeulike:3739492 L3 - citeulike-article-id:3739492 N2 - We present new mid-infrared ($5 - 35\mu$m) and ultraviolet (1539 -- 2316 \AA) observations of the interacting galaxy system Arp 143 (NGC 2444/2445) from the Spitzer Space Telescope and GALEX. In this system, the central nucleus of NGC 2445 is surrounded by knots of massive star-formation in a ring-like structure. We find unusually strong emission from warm H$_2$ associated with an expanding shock wave between the nucleus and the western knots. At this ridge, the flux ratio between H$_2$ and PAH emission is nearly ten times higher than in the nucleus. Arp 143 is one of the most extreme cases known in that regard. From our multi-wavelength data we derive a narrow age range of the star-forming knots between 2 Myr and 7.5 Myr, suggesting that the ring of knots was formed almost simultaneously in response to the shock wave traced by the H$_2$ emission. However, the knots can be further subdivided in two age groups: those with an age of 2--4 Myr (knots A, C, E, and F), which are associated with $8\mu$m emission from PAHs, and those with an age of 7-8 Myr (knots D and G), which show little or no $8\mu$m emission shells surrounding them. We attribute this finding to an ageing effect of the massive clusters which, after about 6 Myr, no longer excite the PAHs surrounding the knots. TI - Powerful H$_2$ Emission and Star Formation on the Interacting Galaxy System Arp 143: Observations with Spitzer and GALEX KW - arp143 KW - galaxies KW - galex KW - interacting KW - spitzer AU - Beirão, P AU - Appleton, PN AU - Brandl, BR AU - Seibert, M AU - Jarrett, T AU - Houck, JR PY - 2008/Dec/02/ UR - http://arxiv.org/abs/0812.0450 ER -