1. Molecular Line Measurements of Luminous Infrared Galaxies (LIRGs) AO 4 David Cotten Alexandre Roman-Lopes Carol Lonsdale Ximena Fernandez Advisor: Chris Salter
Gas is turning into stars extremely rapidly with its circumnuclear volume. The dust heating associated with these intense bursts of star formation produce a large increase in IR luminosity and favorable conditions for radio maser emission.

2. Luminous Infrared Galaxies (LIRGs)
Emit most of the energy in the infrared
Lir > 1011 L
Found in interacting/merging systems
ULIRGs: Lir > L
Mostly advanced mergers

3. Arp 220 λ6 cm excited OH transitions HCN Methanol Methanimine
Prototype of this type of system. It has twin nuclei, strong OH maser emission, and 21-cm line absorption.
Salter et al. 2008

4. Observing Targets IC 860 Zw049.057 z=0.012943 log(Lir )=10.78

5. Spectral Line Observations
L-Band Wide Receiver ( GHz)
Wideband Arecibo Pulsar Processor (WAPP) Spectrometer
HI Line: 1420 Mhz
OH main-line: 1665-MHz
OH main-line: 1667-MHz
OH satellite line: 1612-MHz
OH satellite line: 1720-MHz
OH main-lines: 1637 & 1639 MHz, Formic Acid:1638 MHz
HCN line: 1346 MHz
HCO+ line: 1270 MHz
Observing technique: Double Position Switching (DPS)

6. IC860 IC860 OH main-lines: 1665 & 1667-MHz HI Line
OH satellite lines: 1612 & 1720-MHz
OH main-lines: 1637 & 1639 MHz, Formic Acid:1639 MHz
HI lines
OH main line
HCN line: 1346 MHz
HCO+ line: 1270 MHz

7. Zw049.057 OH main-lines: 1665 & 1667-MHz HI Line
OH satellite lines: 1612 & 1720-MHz
OH main-lines: 1637 & 1639 MHz, Formic Acid:1639 MHz
HI lines
OH main line
HCN line: 1346 MHz
HCO+ line: 1270 MHz

8. New detection of the Satellite Lines in Zw049.057!
Both lines have conjugate behavior: two transitions competing for the same pumping photons

9. Estimates for Column Density