This proposal aims to continue the GBT Diffuse Ionized Gas Survey at Low frequencies (GDIGS-Low). GDIGS-Low is mapping the inner galaxy (-5<l<32 deg |b|<1 deg) in hydrogen radio recombination lines (HRRLs) at 340 and 800 MHz to determine the properties of the dense warm ionized medium (D-WIM) in the Galactic plane. Through this survey we will answer the following questions (i) What are the physical properties of the D-WIM?, (ii) How are the physical properties of the D-WIM affected by radiative feedback?, (iii) What is the relationship between the D-WIM and HII regions?, and (iv) Are O stars the primary source of ionization for the D-WIM?
Answering these questions will be possible using multi-frequency HRRLs at 340, 800 and 5000 MHz, from which changes in the line intensity allow for gas density and path lengths to be determined. The 5 GHz observations come from the successful GBT survey, GDIGS.
| Name | Institution |
|---|---|
| Pedro Salas * | Green Bank Observatory |
| Kimberly Emig | National Radio Astronomy Observatory |
| Anish Roshi | Florida, University of Central |
| Trey Wenger | |
| Matteo Luisi | Westminster College |
| Loren Anderson | West Virginia University |
| Allison Smith | National Astronomy and Ionosphere Center ; Georgia, University of |
| Leonardo Supan | Instituto de Astronomía y Física del Espacio |
| Dylan Linville | West Virginia University |
| Poojapriyatharsheni Jeyasingh | Lady Doak College |
| Mayumi Sato | Bielefeld, Universität |
* indicates the PI