  Small-scale impulsive events, known as nanoflares, are thought to be one of
the prime candidates that can keep the solar corona hot at its multi-million
Kelvin temperature. Individual nanoflares are difficult to detect with the
current generation instruments; however, their presence can be inferred through
indirect techniques such as a Differential Emission Measure (DEM) analysis.
Here we employ this technique to investigate the possibility of nanoflare
heating of the quiet corona during the minimum of solar cycle 24. During this
minimum, active regions (ARs) were absent on the solar-disk for extended
periods. In the absence of ARs, X-ray bright points (XBP) are the dominant
contributor to disk-integrated X-rays. We estimate the DEM of the XBPs using
observations from the Solar X-ray Monitor (XSM) onboard the Chandrayaan-2
orbiter and the Atmospheric Imaging Assembly (AIA) onboard the Solar Dynamic
Observatory. XBPs consist of small-scale loops associated with bipolar magnetic
fields. We simulate such XBP loops using the EBTEL hydrodynamic code. The
lengths and magnetic field strengths of these loops are obtained through a
potential field extrapolation of the photospheric magnetogram. Each loop is
assumed to be heated by random nanoflares having an energy that depends on the
loop properties. The composite nanoflare energy distribution for all the loops
has a power-law slope close to -2.5. The simulation output is then used to
obtain the integrated DEM. It agrees remarkably well with the observed DEM at
temperatures above 1 MK, suggesting that the nanoflare distribution, as
predicted by our model, can explain the XBP heating.
