Extragalacc HF Molecular Line Observaons from Herschel SPIRE and HIFI Spectroscopy Steve Lord, Raquel Monje, Nanyao Lu, Yinghe Zhao, Darek Lis, Tom Phillips, David Neufeld, Edith Falgarone The HF (J=1-0) transion at 1.23 THz (243 um) is providing a new diagnosc probe of the molecular gas abundance, excitaon, and column density toward bright nuclei. During the Herschel mission, this transion was detected and resolved in four with HIFI and gave 12 upper limits (below right). SPIRE gave strong detecons of HF emission in 15 sources and absorpon in 11 sources. (Data were taken from the Key program of Lu et al, the OT program of Lord et al., and the Herschel Archive). HIFI (resolved) 4 detecons, 12 upper limits Mrk 231 SPIRE Detecon (Van NGC 253 detecon in 3 LO seng with HIFI showed such der Werf) (broad red hump) The 2nd column shows the H and V polarizaon excellent signal to noise that it could be deconvolved from the resolved by HIFI! (central peak). separately. They should agree to confirm a double sideband. Here HF absorpon and emission is (unresolved) detecon. SPIRE 26 detecons Likewise, M82 absorpon feature compared with H2CO absorpon. (blue absorpon feature).

The para- H2O 220-211 at 1.229 THz is typically seen alongside HF transion at 1.232 THz

IRAS 13120-5453 NGC 6701 IRAS 05442+1732 MRK 231 NGC 253

MGC-03-04-014 NGC 5135 M 231 NGC 1068 CO J=1-0 for comparison shown below. The HF detecon is centered on Vsys.

NGC 4945 M82

NGC 7130 NGC 3256 NGC 7552 NGC 7469 Emission

IRASF 17207-0014 NGC 2623 Mrk 273 IRASF 16399-0937 NGC 1365 Maffei 2 Absorpon

NGC 2146 SE IRAS 17578-0400 CGCG 049-057 UGC 05101

IC 342 NGC 1068

NGC 6240 NGC 0317B MGC+08-11-002 NGC 6286a

Arp 220 UGC 08739 Arp 299 NGC 23 Discussion NGC 2146 It has been recognized (Neufeld et al. 2005, 2010) via fundamental energec consideraons that HF is the dominant NGC 3256 reservoir of fluorine in the ISM. Preliminary Herschel studies idenfied the transion in Milky Way objects while subsequent Herschel observaons have allowed us to extend our view to IR-bright galaxy nuclei and even to their spiral arms (e.g. NGC 2146 SE). Here we show numerous examples the J=1-0 HF transion occurring both absorpon and emission toward IR-bright galacc nuclei. While SPIRE has yielded the strong detecons shown above, there is lile assurance that, within the profiles shown, we are not seeing the superposion of regions of emission and absorpon, thus making interpretaon difficult. E.g.: In NGC 253 the combinaon of the two effects yields a p-Cygni profile, which Monje et al. (2013) interpret as tracing two velocity components: in-fall and oulow toward the nucleus. From this example we see the need for high spectral resoluon observaons of the line. Below, we show evidence that the emission regions are consistent with regions of warm dust which may fill the beam, conceivably the result of AGN-heang (see talk here of M. Pereira Santaella) while the absorpon lines may originate in a narrow line-of-sight to a background nuclear connuum IC 694 NGC 3690 source. (See figure below). Is this line, in emission, a new AGN diagnosc? Clearly high-z ALMA studies are needed here! Counter-examples to the simplisc asserons made above are apparent in the HF absorpon seen toward the - forming region of NGC2146 SE and the HF emission seen toward the non-AGN NGC 3256. But the interpretaon of HF spectra are just now beginning with these discoveries. "Dust Temperature" vs. HF Absorpon for 24 SPIRE –detected galaxies 0.5

NGC 1068 0.4 Absorpon Emission 0.3 Cen A absorpon NGC 4418 0.2 emission F(25 um) / F(60 um) 0.1

Depending on the amount of cold molecular gas in 0. the line of sight to the central connuum source -0.4 -0.2 0. 0.2 0.4 0.6 (pencil beam) vs. the amount of warm gas in the HF Line/Connuum (241 um) main beam (19" in diameter) HF may be seen in emission or absorpon. In NGC1068 for example, NGC 6240 the main beam includes the inner region of the Circinus starburst ring, which may account for the strong HF emission seen.