A type star
From Aetilc
An A-type main-sequence star (A V) or A dwarf star is a main-sequence (hydrogen-burning) star of spectral type A and luminosity class V. These stars have spectra which are defined by strong hydrogen Balmer absorption lines. They have masses from 1.4 to 2.1 times the mass of the Sun and surface temperatures between 7,600 and 11,500 K. A-type stars are fully radiative and thus are not expected to harbor a magnetic dynamo. As a consequence, because they do not have strong stellar winds they lack a means to generate X-ray emission.
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[edit] Planets
A-type stars are young (typically few hundred million years) and many emit infrared radiation beyond what would be expected from the star alone. This IR excess is attributable to dust emission from a debris disk where planets form. Surveys indicate massive planets commonly form around A-type stars although these planets are difficult to detect using the Doppler spectroscopy method. This is because A-type stars typically rotate very quickly, which makes it very difficult to measure the small Doppler shifts induced by orbiting planets since the spectral lines are very broad. However, this type of massive star eventually evolves into a cooler red giant which rotates more slowly and thus can be measured using the radial velocity method.
