GBT20A-516
GOTHAM-Low: Large Carbon Molecules and Anomalous Molecular Absorption
Abstract
We propose to expand the coverage of the GOTHAM Project to include the S- and C-bands. This work carries the same potential for molecular discovery inherent to all such surveys. These lower frequencies are best for detecting the most intense transitions of our target PAH species. The very large carbon species (both linear and aromatic) that we have been detecting with GOTHAM have >100 intense transitions below 5 GHz. While we are unlikely to detect any of these individually, the addition of this total flux to our matched filtering analyses may provide non-trivial increases in our detection thresholds, and perhaps even enable new detections entirely. In addition, we will be focusing on what molecules in this source demonstrate anomalous microwave absorption: that is, they are seen in absorption against the cosmic microwave background indicating an excitation temperature <2.7 K. GOTHAM will soon report the first detection of this behavior in the ~29 GHz, 3(1,2) - 3_(1,3) transition of H2CO. The corresponding transition of the structurally similar H2CCN molecule falls in S-band at ~2.2 GHz. We have designed the observations to be flexible and Operator-driven to maximize their utility in filling the scheduling gaps.
Investigators
| Name | Institution |
|---|---|
| GBT Operator | Green Bank Observatory |
| Andrew Burkhardt | Center for Astrophysics | Harvard & Smithsonian; Wellesley College; Worcester State University |
| Brett McGuire * | National Radio Astronomy Observatory; Massachusetts Institute of Technology |
| Ilsa Cooke | British Columbia, University of; Rennes 1, Université de |
| CI XUE | Massachusetts Institute of Technology |
| Michael McCarthy | Center for Astrophysics | Harvard & Smithsonian |
| Ryan Loomis | National Radio Astronomy Observatory |
| Mark Siebert | Cornell University; Virginia, University of; Chalmers University Of Technology |
| Tony Remijan | National Radio Astronomy Observatory |
| Kin Long Kelvin Lee | Massachusetts Institute of Technology; Center for Astrophysics | Harvard & Smithsonian |
* indicates the PI