The understanding of the interstellar medium (ISM) and star formationin the low-metallicity environment is crucial to constrain formationof stars and galaxies of the first generation. The local extremelylow-metallicity galaxies (XMPGs) with Z<Zsun/20 offer the uniquelaboratory with nearly metal-free environment that mimics thecondition in the early universe. Previous infrared studies havefocused on their integrated properties due to their small sizes andfaint brightness. The general conclusion is that they show dramaticdifferent ISM and star formation properties from more metal-richgalaxies, and that a large diversity in the properties is also seenamong XMPGs alone. The high resolution combined with its multiplefar-IR bands of Herschel will revolutionize the study of ISM and starformation in XMPGs through the spatially-resolved images of dustproperties (mass and temperature) and SFRs. By relating the dust andstar formation properties to the local physical conditions, we canstart to understand the underlying physical mechanisms that regulateISM and star formation processes in the extremely low-metallicityenvironment. We propose to obtain deep map of the dust emission inthree XMPGs with Herschel PACS and SPIRE photometer. These threeobjects are carefully selected to facilitate the spatially-resolvedstudy, i.e. the large size and previous IR detections bySpitzer. Combined with a rich ancillary data, we will (1) model dustemission to derive dust properties and then relate it to the localphysical properties; (2) derive reliable SFRs by combining IR-basedobscured SFRs and UV-based unobscured ones, from which we then canunderstand the star formation processes at sub-kpc scales.
Publication
Spatially resolved dust emission of extremely metal-poor galaxies* | Zhou Luwenjia et al. | Monthly Notices of the Royal Astronomical Society Volume 458 Issue 1 p.772-780 | 458 | 10.1093\\/mnras\\/stw345 | 2016MNRAS.458..772Z | http://adsabs.harvard.edu/abs/2016MNRAS.458..772Z
Inefficient star formation in extremely metal poor galaxies | Shi Yong et al. | Nature Volume 514 Issue 7522 pp. 335-338 (2014). | 514 | 10.1038\\/nature13820 | 2014Natur.514..335S | http://adsabs.harvard.edu/abs/2014Natur.514..335S
Instrument
PACS_PacsPhoto_largeScan, SPIRE_SpirePhoto_small
Temporal Coverage
2012-04-06T00:34:48Z/2012-11-19T05:55:03Z
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, shi et al., 2013, 'Extremely-metal poor galaxies: mapping dust emission', SPG v14.2.0, European Space Agency, https://doi.org/10.5270/esa-q4fbs1o
