| Name | OT1_mrubio_1 |
| Title | Clumping in OB-star winds |
| URL | http://archives.esac.esa.int/hsa/whsa-tap-server/data?retrieval_type=OBSERVATION&observation_id=1342212044&instrument_name=PACS&product_level=LEVEL0&compress=true |
| DOI | https://doi.org/10.5270/esa-te943hl |
| Author | rubio, m. |
| Description | Massive stars, their nature and evolution, play a important role at all stages of the Universe. Through their radiatively driven winds they influence on the dynamics and energetics of the interstellar medium. The winds of OB stars are the most studied case. Commonly, the mass-loss rates of luminous OB stars are inferred from several types of measurements, the strengths of UV P Cygni lines, H-alpha emission and radio and FIR continuum emission. Recent evidence indicates that currently accepted mass-loss rates may need to be revised downwards when small-scale density inhomogeneities (clumping) are taken into account. We argue that only a consistent treatment of ALL possible diagnostics, scanning different parts of the winds, and analyzed by means of state of the art model atmospheres, will permit the determination of true mass-loss rates. To this end we have assembled a variety of multi-wavelength data, but one crucial observational set is missing: far-IR diagnostics of free-free emission, which uniquely constrain the clumping properties of the wind at intermediate heights.We propose, therefore, to use PACS photometric mode to fill this crucial gap, studying the 70 and 110 micron fluxes of a carefully selected sample of 29 O4-B8 stars. These observations will provide the missing information to derive the clumping properties of the entire outflow, to understand the wind physics, and to obtain reliable massloss rates. |
| Publication |
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| Instrument | PACS_PacsPhoto_largeScan |
| Temporal Coverage | 2010-12-16T16:21:47Z/2013-03-31T23:39:14Z |
| 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 | 2013-09-30T23:38:22Z |
| Keywords | Herschel, HSC, submillimetre, far-infrared, HIFI, PACS, SPIRE |
| Publisher And Registrant | European Space Agency |
| Credit Guidelines | European Space Agency, rubio et al., 2013, 'Clumping in OB-star winds', SPG v14.2.0, European Space Agency, https://doi.org/10.5270/esa-te943hl |