We propose to observe a small sample of nearby major mergers in threedifferent merging stages with Herschel PACS and SPIRE photometers.The observations will allow us to derive the dust surface density andfrom this the total gas surface density. Together with alreadyavailable tracers of the SFR (Spitzer 24 micron and GALEX FUV) we can study the Kennicutt-Schmidt law.High resolution data of the atomic gas content (partlyalready available and partly applied for at the EVLA) allow usfurthermore to make a distinction between atomic and molecular gas.The derivation of the total gas mass via the dust emissioninvolves less serious uncertainties than the use of CO as a tracerof the molecular gas.With these observation we aim to address the open question whymerging galaxies form stars at about a 10 times higher rate comparedto their gas mass than quiescent galaxies.Our recent numerical models explain this by a higher turbulence whichmake the step from low-density to high-density (star--forming) gas moreefficient. It makes specific prediction about the efficiency of theconversion from atomic to molecular gas, which directly affectsthe ratio between SFR and gas mass, as a function of merger stage.The selection of our sample and the proposed observationswill allow us to test the predictionsof the simulations and provide therefore an opportunity toimprove our understanding of the physical processesunderlying star-formation and of the cosmic star formation history
Publication
DustPedia: Multiwavelength photometry and imagery of 875 nearby galaxies in 42 ultraviolet-microwave bands | Clark C. J. R. et al. | Astronomy & Astrophysics Volume 609 id.A37 30 pp. | 609 | 10.1051\\/0004-6361\\/201731419 | 2018A&A...609A..37C | http://adsabs.harvard.edu/abs/2018A%26A...609A..37C
Reproducing the Universe: a comparison between the EAGLE simulations and the nearby DustPedia galaxy sample | Trcka Ana et al. | Monthly Notices of the Royal Astronomical Society | null | null | 2020MNRAS.494.2823T |
Dust emissivity and absorption cross section in DustPedia late-type galaxies | Bianchi S. et al. | Astronomy and Astrophysics | null | null | 2019A&A...631A.102B |
DustPedia: the relationships between stars, gas, and dust for galaxies residing in different environments | Davies J. I. et al. | Astronomy and Astrophysics | null | null | 2019A&A...626A..63D |
Old and young stellar populations in DustPedia galaxies and their role in dust heating | Nersesian A. et al. | Astronomy and Astrophysics | null | null | 2019A&A...624A..80N |
Fraction of bolometric luminosity absorbed by dust in DustPedia galaxies | Bianchi S. et al. | Astronomy & Astrophysics Volume 620 id.A112 21 pp. | 620 | 10.1051\\/0004-6361\\/201833699 | 2018A&A...620A.112B | http://adsabs.harvard.edu/abs/2018A%26A...620A.112B
UV to submillimetre luminosity functions of TNG50 galaxies | Trcka Ana et al. | Monthly Notices of the Royal Astronomical Society | null | null | 2022MNRAS.516.3728T |
DustPedia: A Definitive Study of Cosmic Dust in the Local Universe | Davies J. I. et al. | Publications of the Astronomical Society of the Pacific Volume 129 Issue 974 pp. 044102 (2017). | 129 | 10.1088\\/1538-3873\\/129\\/974\\/044102 | 2017PASP..129d4102D | http://adsabs.harvard.edu/abs/2017PASP..129d4102D
Instrument
PACS_PacsPhoto_largeScan, SPIRE_SpirePhoto_large
Temporal Coverage
2013-02-21T17:57:41Z/2013-03-25T00:03:50Z
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.
European Space Agency, lisenfeld et al., 2013, 'Herschel observations of nearby mergers: understanding the process of star-formation along cosmic time', SPG v14.2.0, European Space Agency, https://doi.org/10.5270/esa-5xymlb8