| Name | GT2_astutz_2 |
| Title | Probing the physical cconditions of prestallar cores on the verge of collapse |
| URL | http://archives.esac.esa.int/hsa/whsa-tap-server/data?retrieval_type=OBSERVATION&observation_id=1342239787&instrument_name=PACS&product_level=LEVEL0&compress=true |
| DOI | https://doi.org/10.5270/esa-cqcrosp |
| Author | European Space Agency |
| Description | Low-mass molecular cloud cores are the birthplace of solar-type stars. Therefore, a thorough understanding of star formation requires detailed knowledge of core properties. Submm/mm observations have identified a class of very cold pre-stellar cores on the brink of collapse. Isolated cores, which have a relatively simple structure, are ideal laboratories for studying the star formation process; they can be directly compared with simple theoretical predictions, such as MHD simulations of single cores. Although the chemical and dynamical state of these cores has been well characterized by molecular line observations, we still lack a comprehensive understanding of two fundamental physical parameters: temperature and density. The temperature and density structure regulate the dynamical state of the objects, including any possibility for subsequent fragmentation. For the globule CB 244 we demonstrated that Herschel has the unique capability to provide this information. Due to their short free fall times (of order 10^5 years), pre-stellar cores are rare objects; therefore, we carefully target two representative well-studied pre-stellar cores. Molecular line profiles for these objects show clear signatures of infall motions indicating that they are birthplaces of new stars. The low dust temperatures of these sources (5-15 K) imply that the bulk of the emission will emerge at FIR wavelengths. We therefore propose to observe the targeted objects with PACS and SPIRE. Together with near-infrared extinction maps and submillimetre continuum data, we will be able to reconstruct the dust temperature and density maps, breaking the degeneracy with dust opacity properties. In order to disentangle the effects of dust temperature, density, and opacity, fluxes from both sides of the SED peak are required: Herschel is the only mission which can provide these data with the required sensitivity. |
| Publication | Constraining the Dust Opacity Law in Three Small and Isolated Molecular Clouds . Webb K. A. et al. . The Astrophysical Journal, Volume 849, Issue 1, article id. 13, 12 pp. (2017). . 849 . 10.3847\/1538-4357\/aa901c . 2017ApJ...849...13W , Intensity-corrected Herschelxa0 Observations of Nearby Isolated Low-mass Clouds . Sadavoy Sarah I. et al. . The Astrophysical Journal, Volume 852, Issue 2, article id. 102, 26 pp. (2018). . 852 . 10.3847\/1538-4357\/aaa080 . 2018ApJ...852..102S , Distribution of methanol and cyclopropenylidene around starless cores★ . Spezzano S. et al. . Astronomy and Astrophysics . null . null . 2020A&A...643A..60S , |
| Instrument | PACS_PacsPhoto_largeScan, SPIRE_SpirePhoto_large |
| Temporal Coverage | 2012-02-29T20:35:23Z/2012-03-29T18:41:46Z |
| 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. |
| Creator Contact | https://support.cosmos.esa.int/h®erschel/ |
| Date Published | 2012-09-29T17:13:23Z |
| Publisher And Registrant | European Space Agency |
| Credit Guidelines | European Space Agency, 2012, Probing The Physical Cconditions Of Prestallar Cores On The Verge Of Collapse, SPG v14.2.0, European Space Agency, https://doi.org/10.5270/esa-cqcrosp |