2015 Seminar List:
We present results of infrared observations toward eight dense molecular cores with the AKARI space telescope at eight bands (3, 4, 7, 11, 65, 90, 140, and 160 ¥ìm).
These cores were previously known to be starless, and show characteristic features in their molecular lines such as a broad line width and/or asymmetric line shapes indicative of internal motions.
With complementary infrared data from the Space Telescope and N2H+ and HCN 1-0 lines from the KVN radio telescopes, two of eight cores seem to harbor faint protostars. At least 10 new protostars having a bolometric luminosity of 0.3?4.4 L¢Á are identified in regions of L1582A and L1041-2, and seem to force the environment of the cores more turbulent than other starless cores. On the other hand, others are found to be starless and may be at the moment of changing their dynamically stable to unstable status.
They also may be externally affected by nearby stars and begin to expand or oscillate which may lead to trigger the inward motions in the cores for resulting in eventual star formation.
Among eight dense cores, six dense cores with a coreshine effect may be long-lived objects in the life timescale of a few free-fall time because they have micrometer-sized dust grains made by the continuous growth processes.