ALFALFA Graduate Student Project

Proposal Title: Chemical abundances of low mass galaxies
Student Name: Amélie Saintonge
Adviser: Riccardo Giovanelli
Context: Part of Ph.D. thesis
Institution: Cornell
Time frame: (e.g. mid-2008, etc.) 2007
Other collaborators: Martha Haynes, Brian Kent, Sabrina Stierwalt, Liese van Zee, Noah Brosch, John Salzer, Igor Karachentsev
Publication expected? yes, spring 2007

Description: (up to ~ 500 words)

We are looking to build a unique sample of very low optical surface brightness dwarf galaxies, among the ALFALFA galaxies showing the smallest HI masses. These objects that are likely to be gas rich, and metal poor could be undergoing their first episodes of star formation, and are therefore of significant interest in the broader context of structure formation.

Follow-up observations will be made in narrow band Halpha to determine the location of HII regions, mainly with the WISE 0.9m telescope. This will be followed by optical spectrocopy at the Hale 5m telescope to determine Oxygen abundances in these systems, as well as broad band imaging at the WIYN 0.9m telescope. The combination of metallicities and colours will allow us to get a good picture of the evolutionary state of these low mas, gas rich systems.

The ALFALFA galaxies to be studied will be chosen based mainly on their HI mass. This means that galaxies with narrow velocity widths (w<50 km/s) and very low redshifts (cz<4000 km/s) will be the most appropriate targets for this study. The galaxies will be selected in a variety of environments, including the Virgo region, nearby groups such as NGC672 (or whichever region I am going to look at in the coming months...change accordingly), as well as lower density regions.

ALFALFA region:Fall and Spring data, galaxies selected based on line width and redshift
ALFALFA data to be used:
  1. Level I data to produce tentative catalogs to perform follow-up observations,
  2. Level II data to produce final catalog of HI parameters
Other data sets to be used:
  1. Follow-up optical spectroscopy (Palomar 5m)
  2. imaging (WISE 0.9m, WIYN 0.9m)
Products to be delivered:
  1. Signal extraction algorithm (in progress);
  2. Catalog of HI sources at very low redshift
  3. database of metallicities for these galaxies.

Milestones (if duration is > 1 yr):

First follow-up optical observationsPalomar, WIYN Fall 2005in progress
Preliminary sampleFirst catalog with HI parameters, metallicities, and broad-band photometry, ongoing follow-up observations Fall 2006  
Submit publicationResults of first sample Spring 2007  

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Last modified: Thu Oct 6 08:48:01 EDT 2005 by martha