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The low frequency quasi periodic oscillations (QPOs) are commonly observedduring hard states of black hole binaries. Several studies have establishedvarious observational/empirical correlations between spectral parameters andQPO properties, indicating a close link between the two. However, the exactmechanism of generation of QPO is not yet well understood. In this paper, wepresent our attempts to comprehend the connection between the spectralcomponents and the low frequency QPO observed in GRS 1915+105 using the datafrom NuSTAR. Detailed spectral modeling as well as the presence of the lowfrequency QPO and its energy dependence during this observation have beenreported by Miller et al. (2013) and Zhang et al. (2015) respectively. Weinvestigate the compatibility of the spectral model and energy dependence ofthe QPO by simulating light curves in various energy bands for small variationof the spectral parameters. The basic concept here is to establish connection,if any, between the QPO and the variation of either a spectral component or aspecific parameter, which in turn can shed some light on the origin of the QPO.We begin with the best fit spectral model of Miller et al. (2013) and simulatethe light curve by varying the spectral parameter at frequencies close to theobserved QPO frequency in order to generate the simulated QPO. Further wesimulate similar light curves in various energy bands in order to reproduce theobserved energy dependence of RMS amplitude of the QPO. We find that theobserved trend of increasing RMS amplitude with energy can be reproducedqualitatively if the spectral index is assumed to be varying with the phases ofthe QPO. Variation of any other spectral parameter does not reproduce theobserved energy dependence.

Investigating the connection between Quasi Periodic Oscillations and spectral components with NuSTAR data of GRS 1915+105