| Description |
We propose to use the The Galactic center (GC) a local extragalactic laboratory tounderstand the chemistry and the heating mechanisms in nearby galactic nuclei. Thecentral 30 pc region around the black hole, Sgr A*, contains all the different typeof activity found in extragalactic nuclei, namely, massive stellar clusterscreating large photodissociation regions (PDR), shocks, molecular clouds irradiatedby strong X-rays (XDRs), and the site of Cosmic Rays (CRs) acceleration as shown byHESS. We plan to map this region with SPIRE in the high spectral resolution mode and with HIFI in selected molecular ions H$_3$O$^+$, OH$^+$, and H$_2$O$^+$ claimed totrace XDRs and/or CRs. This unique data set will provide the possibility to understandthe origin of the large column densities of this hydrides found in galactic nucleiwith different type of activity and the role of the PDR-XDR-CR chemistries in theirformation. The SPIRE data cubes will have a huge legacy value providing the full FIRinventory of the atomic and molecular gas across the central 50 pc of the Galaxy. Westress that only the combination of the high spectral resolution of HIFI and thespatial distribution provided the proposed mapping will have the possibility todistinguish which of the different components of the molecular gas along the line ofsight correspond to the ones associated with XDRs PDRs and eventually CRsacceleration sites. |
| Keywords |
Herschel Space Observatory data, ESA Herschel mission dataset, far-infrared astronomy observations, submillimeter astronomy data, infrared space telescope observations, PACS photometer data, PACS spectrometer data, SPIRE photometer data, SPIRE Fourier transform spectrometer data, HIFI heterodyne spectroscopy data, far-infrared spectroscopy dataset, submillimeter spectral line observations, cold universe observations dataset, star formation infrared data, molecular cloud far-infrared observations, interstellar medium spectroscopy data, protoplanetary disk infrared observations, galaxy evolution far-infrared data, dust emission submillimeter observations, cosmic infrared background measurements, extragalactic infrared survey data, calibrated level 2 data products, FITS files astronomy, spectral cubes far-infrared, flux-calibrated maps, continuum photometry data, spectral energy distribution measurements, ESA Herschel Science Archive data |
