A dataset provided by the European Space Agency

Name OT2_jvaillan_1
Title Differential Heating of Magnetically Aligned Dust Grains


DOI 10.5270/esa-f5p31k1
Author vaillancourt, j.
Description The observations proposed here are designed to search for the effect of differential heating on asymmetric dust-grains aligned with respect to an interstellar magnetic-field and heated by a localized radiation source. The grains are known to be asymmetric and aligned from observations of background starlight polarization. Modern theories on grain alignment suggest that photons from stars embedded in the foreground cloud are a key ingredient of the physical mechanism responsible for alignment. This theory predicts a relation between the grain-alignment efficiency and the angle between the magnetic field and the direction to the aligning radiation-source. This effect has been tentatively observed in a source with a very simple geometry: the aligning photons are primarily from a single localized source (i.e., a singe star) and the local magnetic-field direction is known to be fairly uniform. Such a region also has consequences for the distribution of grain heating. For example, asymmetric grains whose largest cross-sections are normal to the incident stellar radiation will reach warmer equilibrium temperatures compared to grains whose largest cross-section is parallel to that direction. This should be observed as an azimuthal dependence of the dust color-temperature. As we show in this proposal, such a dependence is hinted at in work using IRAS data at 60 and 100 micron. If this effect is real then a stronger signal is expected using longer wavelength data. Here we propose to search for this signal using Herschel-PACS photometry at 100 and 160 micron.
Instrument PACS_PacsPhoto_largeScan
Temporal Coverage 2012-08-23T23:31:56Z/2012-08-24T01:37:07Z
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 ┬Ám range, bridging the gap between earlier infrared space missions and groundbased facilities.
Creator Contact https://support.cosmos.esa.int/herschel/
Date Published 2013-02-24T00:35:08Z
Publisher And Registrant European Space Agency
Credit Guidelines European Space Agency, 2013-02-24T00:35:08Z, OT2_jvaillan_1, SPG v14.2.0. https://doi.org/10.5270/esa-f5p31k1