Herschel PACS spectroscopy of the [CII] emission line at 158 microns is proposed for a carefully selected sample of 123 sources that already have complete low and high resolution mid-infrared spectra between 5 microns and 35 microns from the Spitzer Infrared Spectrograph, and which also have spectral energy distributions (SEDs) from IRAS and Akari photometry. [CII] 158 um is the strongest far-infrared emission line and therefore crucial to compare with other features in luminous, dusty galaxies. Sources have 0.004 < z < 0.34 and 43.0 < log L(IR) < 46.8 (erg per sec) and cover the full range of starburst galaxy and AGN classifications. Obtaining these [CII] line fluxes with PACS will allow: 1. determining how precisely [CII] luminosity measures star formation rate by comparing to PAH features and emission lines that arise in starburst galaxies; 2. determining how [CII] luminosity and equivalent width changes with starburst-AGN fraction, by comparing with strength and equivalent width of PAH and [NeII] emission arising from starbursts, and with strength of high ionization lines [NeV] and [OIV] and silicate absorption or emission arising from AGN; 3. determining how [CII] luminosity and equivalent width changes with dust temperature and bolometric luminosity, as derived from spectral energy distributions, and whether this depends on the starburst-AGN fraction. These determinations will allow interpretation of high redshift sources for which the only available diagnostics are the luminosity and equivalent width of the [CII] line and the far-infrared rest-frame SED. The total observing program requires 20.2 hours of Herschel observing time.
Publication
Strong C+ Emission in Galaxies at z virgul 1-2: Evidence for Cold Flow Accretion Powered Star Formation in the Early Universe . Brisbin Drew et al. . The Astrophysical Journal, Volume 799, Issue 1, article id. 13, 18 pp. (2015). . 799 . 10.1088/0004-637X/799/1/13 . 2015ApJ...799...13B , A Herschel-PACS Far-infrared Line Emission Survey of Local Luminous Infrared Galaxies . Díaz-Santos T. et al. . The Astrophysical Journal, Volume 846, Issue 1, article id. 32, 22 pp. (2017). . 846 . 10.3847/1538-4357/aa81d7 . 2017ApJ...846...32D , [C II] 158 μm Luminosities and Star Formation Rate in Dusty Starbursts and Active Galactic Nuclei . Sargsyan L. et al. . The Astrophysical Journal, Volume 755, Issue 2, article id. 171, 13 pp. (2012). . 755 . 10.1088/0004-637X/755/2/171 . 2012ApJ...755..171S , Extended [C II] Emission in Local Luminous Infrared Galaxies . Díaz-Santos T. et al. . The Astrophysical Journal Letters, Volume 788, Issue 1, article id. L17, 5 pp. (2014). . 788 . 10.1088/2041-8205/788/1/L17 . 2014ApJ...788L..17D , Regulating Star Formation in Nearby Dusty Galaxies: Low Photoelectric Efficiencies in the Most Compact Systems . McKinney J. et al. . The Astrophysical Journal . null . null . 2021ApJ...908..238M , The applicability of far-infrared fine-structure lines as star formation rate tracers over wide ranges of metallicities and galaxy types . De Looze Ilse et al. . Astronomy & Astrophysics, Volume 568, id.A62, 34 pp. . 568 . 10.1051/0004-6361/201322489 . 2014A&A...568A..62D , Star Formation Rates from [C II] 158 μm and Mid-i...nfrared Emission Lines for Starbursts and Active Galactic Nuclei . Sargsyan L. et al. . The Astrophysical Journal, Volume 790, Issue 1, article id. 15, 12 pp. (2014). . 790 . 10.1088/0004-637X/790/1/15 . 2014ApJ...790...15S , The Local [C II] 158 μm Emission Line Luminosity Function . Hemmati Shoubaneh et al. . The Astrophysical Journal, Volume 834, Issue 1, article id. 36, 10 pp. (2017). . 834 . 10.3847/1538-4357/834/1/36 . 2017ApJ...834...36H , Neon and [C II] 158 μm Emission Line Profiles in Dusty Starbursts and Active Galactic Nuclei . Samsonyan Anahit et al. . The Astrophysical Journal Supplement Series, Volume 226, Issue 1, article id. 11, 18 pp. (2016). . 226 . 10.3847/0067-0049/226/1/11 . 2016ApJS..226...11S , Early Science with the Large Millimeter Telescope: CO and [C II] Emission in the z = 4.3 AzTEC J095942.9+022938 (COSMOS AzTEC-1) . Yun Min S. et al. . Monthly Notices of the Royal Astronomical Society, Volume 454, Issue 4, p.3485-3499 . 454 . 10.1093/mnras/stv1963 . 2015MNRAS.454.3485Y , Explaining the [C II]157.7 μm Deficit in Luminous Infrared Galaxies—First Results from a Herschel-PACS Study of the GOALS Sample . Díaz-Santos T. et al. . The Astrophysical Journal, Volume 774, Issue 1, article id. 68, 13 pp. (2013). . 774 . 10.1088/0004-637X/774/1/68 . 2013ApJ...774...68D ,
Instrument
PACS_PacsLineSpec_point
Temporal Coverage
2011-05-01T20:06:36Z/2012-03-25T15:21:52Z
Version
SPG v14.2.0
Mission Description
Herschel was launched on 14 May 2009! It is the fourth 'cornerstone' mission in the ESA science programme. With a 3.5 m Cassegrain telescope it is the largest space telescope ever launched. It is performing photometry and spectroscopy in approximately the 55-671 µm range, bridging the gap between earlier infrared space missions and groundbased facilities.
