Near Infrared Halo Emission in the Edge-on Spiral Galaxy ESO 240-G11

• Main Authors: Bernard Rauscher Department, Bernard J. Rauscher, James P. Lloyd, David Barnaby, Doyal A. Harper, Robert F. Loewenstein, Scott A. Severson, Fred Mrozek, J. William, Fulbright Scholar
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: South Pole; South pole
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.42.6550; http://astro.uchicago.edu/cara/research/papers/eso240g11.980409.ps.gz

In an extremely deep K dark band (2.27--2.43 m) image of the southern edge-on spiral galaxy ESO 240-G11, we detect halo emission extending to between 10 h \Gamma1 69 kpc and 15 h \Gamma1 69 kpc away from the disk in vertical cuts near the nucleus. In vertical cuts taken well-away from the nucleus, no halo emission is detected. To our detection limit, these data are well modeled by a spherically symmetric component having an exponential radial surface brightness profile plus a sech(z) disk. The exponential radial surface brightness profile suggests an unusually faint and extended spiral bulge. A ae / r \Gamma3:5 spheroid plus sech(z) disk is nearly as good a fit. It is also possible to fit these data with a ae / r \Gamma2 component tracing the massive halo. However, this requires a larger error in setting the sky level than appears likely. These data, which were taken with a 60 cm infrared optimized telescope at the South Pole, permit surface photometry reaching 25 mag arcsec \.