The role of magnetic fields in star formation July 29, 2016 Please Register or Log in to view the hidden image! A false-color far-infrared image of the star forming region W43; the contours are for molecular gas density. The subregion MM1 located just left of center in not conspicuous in the image but is the site of massive star formation and fragmentation. A new study has mapped the magnetic fields in this region, and found they are not strong enough to prevent further gravitational collapse. Credit: ESA/Herschel and L.Q. Nguyen et al The star forming molecular clump W43-MM1 is very massive and dense, containing about 2100 solar masses of material in a region only one-third of a light year across (for comparison, the nearest star to the Sun is a bit over four light years away). Read more at: http://phys.org/news/2016-07-role-magnetic-fields-star-formation.html#jCp
A couple of important extracts re that article...... "One of the outstanding issues in star formation is the extent to which magnetic fields inhibit the collapse of material onto stars, and this source seems to offer a particularly useful example". "The scientists analyze the magnetic field strengths and show that, even in the least massive fragment the field is not strong enough to inhibit gravitational collapse. In fact, they find indications that gravity, as it pulls material inward, drags the magnetic field lines along".
http://iopscience.iop.org/article/1...F500B9567FA21CBA18A.c3.iopscience.cld.iop.org INTERFEROMETRIC MAPPING OF MAGNETIC FIELDS: THE ALMA VIEW OF THE MASSIVE STAR-FORMING CLUMP W43-MM1 Abstract Here, we present the first results from ALMA observations of 1 mm polarized dust emission toward the W43-MM1 high-mass star-forming clump. We have detected a highly fragmented filament with source masses ranging from 14 M Please Register or Log in to view the hidden image! to 312 M Please Register or Log in to view the hidden image!, where the largest fragment, source A, is believed to be one of the most massive in our Galaxy. We found a smooth, ordered, and detailed polarization pattern throughout the filament, which we used to derived magnetic field morphologies and strengths for 12 out of the 15 fragments detected ranging from 0.2 to 9 mG. The dynamical equilibrium of each fragment was evaluated finding that all the fragments are in a super-critical state that is consistent with previously detected infalling motions toward W43-MM1. Moreover, there are indications suggesting that the field is being dragged by gravity as the whole filament is collapsing.
