Magnetic Fields of the T Tauri Stars in the OrionNebula Cluster

摘要

We analyze the infrared (IR) echelle spectra of 14 T Tauri stars in the Orion NebularCluster (ONC) and measure their mean surface magnetic fields by modeling the Zeeman broadeningin three magnetically sensitive Ti 1 lines near 2.2 pm. We combine these measurements withprevious measurements of stars in Taurus and the TW Hydrae Association (TWA) to suggest thatthe strong magnetic fields commonly detected on T Tauri stars could be of a primordial origin. Thedominance of strong magnetic pressure over gas pressure in the stellar photospheres might alsopartially prohibit the production of X-ray emission.