Prospecting for elements: Galactic halo planetary nebulae abundances and Virgo spiral galaxy color profiles.

Near-infrared Virgo cluster spiral colors. Near-infrared (NIR) surface photometry in J (1.2μm), H (1.6μm) and K (2.2μm) have been obtained for a sample of Virgo cluster spirals; NGC4321, NGC4303, NGC4571, NGC4689, and NGC4254 which span a large range in HI deficiency. The spirals range from a normal gas content to a deficiency of a factor of 10 compared to normal galaxies. Using previous HII region abundance studies along with the NIR colors an attempt has been made to calibrate any correlation between the J-K index to the overall gas phase abundance gradients as a first step to probing the underlying stellar metallicity. Decomposition techniques have been used to produce estimates of spiral bulge/disk masses and luminosities in all three J, H, & K bands, as well as to explore the variation of mass-to-light ratios within the separate galaxy components. An analysis of the NIR colors is performed in an attempt to unravel the similar effects that stellar ages, dust content, metallicity, and some non-stellar emission processes has upon colors. The derived color gradients for the J-K index are very shallow and show a range of behaviors across the galaxy sample.

Author dc:creator

• Howard, Joseph William.

Advisor dc:contributor.advisor

• Henry, Richard C.,

• Spiral galaxies.
• Planetary nebulae.
• Cosmic abundances.
• Physics, Astronomy and Astrophysics.

Handle dc:identifier.uri

http://hdl.handle.net/11244/5684

OAI record oai:identifier

https://shareok.org/server/oai/request?verb=GetRecord&metadataPrefix=dim&identifier=oai%3Ashareok.org%3A11244%2F5684