We propose to use the SPIRE-FTS to map a 8.5.x8.5. (virgul20pc x20pc) region around Sgr B2, the only source that allows studying a burst of star formation in the center of a galaxy (GC) with high spatial resolution even using a single dish telescope (25. = 1 pc).Bright high-mass star forming regions do exist in the disk of the galaxy, but the specific location of Sgr B2 in the GC (where the ambient physical conditions are markedly different compared to the disk) make it the best source to compare with unresolved extragalactic nuclei(M82, the prototype starburst galaxy is virgul400 times more distant and thus 25.=400 pc).Our SPIRE-FTS pointed observations around Sgr B2(M) core and surroundings show strong dust continuum emission as well as emission lines from 12CO and 13CO rotational ladders; NII and CI fine structure lines; emission/absorption of excited H2O and NH3, and line-of-sight absorption of a variety of light hydrides (HF, CH+, CH2, OH+, H2O+, H3O+, NH and NH2) that are difficult, if not impossible, to detect from the ground. Even far from Sgr B2 star forming cores, the expected continuum and line intensities will enable us to map tens of lines over large areas in very reasonable times. Understanding the large scale physics and chemistry of this starburst template in the GC is of great interest as recent Herschel observations are revealing similarly rich spectra in fainter galaxies where, of course, different components overlap in the beam. The proposed spectral maps and SEDs will form a large database that will be a legacy for higher angular resolution studies of extragalactic nuclei.
Publication
The Herschel SPIRE Fourier Transform Spectrometer Spectral Feature Finder - II. Estimating radial velocity of SPIRE spectral observation sources | Scott Jeremy P. et al. | Monthly Notices of the Royal Astronomical Society | null | null | 2020MNRAS.496.4894S |
Instrument
SPIRE_SpireSpectrometer_
Temporal Coverage
2013-03-03T14:07:17Z/2013-03-04T00:53:03Z
Version
SPG v14.1.0
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.
European Space Agency, goicoechea et al., 2013, 'Mapping Sagittarius B2 comma a starburst in the Milky Way.s Galactic Center', SPG v14.1.0, European Space Agency, https://doi.org/10.5270/esa-i7fg8nz
