The word "chromospheric" refers to something related to the chromosphere, which is the outer layer of the sun's atmosphere. It describes phenomena or features happening or occurring in the chromosphere. Full definition
Once thought to be old Population II, galactic - halo - type subdwarf stars, Zeta1 and its companion are more likely to be old disk stars (Da Silva and Foy, 1987), that may be as much as eight billion years old, but more recent analysis of chromospheric activity and rotation with spectral analysis and calibration with other Sol - type stars suggest that the two stars could be as young as 1.5 to three billion years old (Mamajek and Hillenbrand, 2008, Table 13). (members.nova.org)
Similar flare rates were calculated by Maehara et al. 15 and Shibayama et al. 16 using rotation instead of chromospheric emission as the criterion for selecting Sun - like stars with magnetic activity levels similar to the Sun. (nature.com)
To carry out novel investigations based on spectro - polarimetric observations with ground - based and space solar telescopes, with emphasis on the study of the magnetic field in chromospheric and coronal structures and its coupling with the underlying photosphere. (uksolphys.org)