CO Spectral Line Energy Distributions in Orion Sources: Templates for Extragalactic Observations Nick Indriolo & Ted Bergin University of Michigan June 24, th ISMS: WI081

Acknowledgments Javier Goicoechea & Jose Cernicharo – Orion maps in PACS & SPIRE Christine Joblin – Orion Bar HIFI & PACS data Peter Schilke & Darek Lis – Sgr B2 HIFI data June 24, th ISMS: WI082

Background Spectral Line Energy Distribution (SLED): Flux per emission line Sensitive to physical conditions (i.e., density, temperature, radiation field) Can we differentiate between excitation mechanisms (e.g., shocks, PDR, XDR)? What if only a limited number of lines have been observed/detected? June 24, th ISMS: WI083

CO Rotational Ladder CO rotational transitions evenly spaced in frequency Above J≈8 requires space- based observatory Herschel Space Observatory – HIFI: 5≤J≤16; Δv≈0.5 km/s – PACS: 14≤J≤48; Δv≈200 km/s – SPIRE: 4≤J≤13; Δv≈300 km/s June 24, th ISMS: WI084

NGC 253 Herschel SPIRE Spectrum June 24, th ISMS: WI085 Rosenberg et al A&A, 564, A126 1 Jy = W m -2 Hz -1

NGC 253 CO SLED Emission line flux from each transition Curves are for models with variety of conditions Requires multiple components with different physical conditions June 24, th ISMS: WI086 Rosenberg et al A&A, 564, A126

Extragalactic CO SLEDs June 24, th ISMS: WI087 Mashian et al. 2015, ApJ, 802, 81

Spatial Resolution SPIRE-FTS beam sizes at long (red) and short (blue) wavelengths Emission from many regions is blended, and observed region is changing with wavelength/transition June 24, th ISMS: WI088 Spinoglio et al ApJ, 758, 108 NGC 1068 nucleus; CO kpc

Orion Nebula June 24, th ISMS: WI089 Peng et al 2012 A&A, 538, A12; 13 CO 8-7 O’Dell et al. 2008, Handbook of Star Forming Regions, Vol. I O’Dell 2001 ARA&A, 39, 99 Star-forming region about 410 pc away

Orion Nebula: Line Profiles June 24, th ISMS: WI0810 Peng et al A&A, 538, A12

Orion Nebula: Line Profiles June 24, th ISMS: WI0811 Orion Bar (PDR)Orion South (protostars, outflows, PDR)

Line Profile Comparison Broad, more complex profiles including self-absorption in Ori KL and H 2 Peak 1 Decomposition not straightforward in all cases June 24, th ISMS: WI0812

CO SLED: Orion Bar June 24, th ISMS: WI0813

CO SLED: Orion South June 24, th ISMS: WI0814

CO SLED: Orion KL and H 2 Peak 1 June 24, th ISMS: WI0815

Orion H 2 Peak 1 Interpretation Fit with three different components – cool plateau – warm shock – hot shock June 24, th ISMS: WI0816 Goicoechea et al. 2015, ApJ, 799, 102

CO SLED: M 82 and NGC 1068 June 24, th ISMS: WI0817

NGC 1068: scaled to 410 pc June 24, th ISMS: WI0818

NGC 1068 Interpretation Models use XDR, PDR, and shock to fit CO emission line fluxes XDR and shock are favored, but cannot be distinguished Note importance of J=30 point June 24, th ISMS: WI0819 Hailey-Dunsheath et al ApJ, 755, 57

Summary & Future Work CO SLEDs measured in a sizeable sample of galaxies (primarily active) Overall shapes are combinations of different excitation mechanisms and conditions The nearby Orion star-forming region, where conditions are "well-known", can be used to make templates for shocks, PDRs, etc. What combination of these objects/regions can reproduce extragalactic CO SLEDs? June 24, th ISMS: WI0820