  The shape of the ion energy spectra plays a critical role toward determining
the ion energetics, the acceleration mechanisms and the possible sources of
different plasma and suprathermal ion populations. The determination of the
exact shape of the total particle spectrum, provide the necessary means to
address the inner heliosheath (IHS) dynamics. Apart from various modeling
efforts, a direct fit to the measured ion spectra for an extended energy range
of $\sim$0.11 to 344 MeV has not been performed to date.
  We use an extended set of combined 0.11-55 keV ENA measurements from the
Interstellar Boundary Explorer (IBEX-Lo and IBEX-Hi) and Cassini/Ion and
Neutral Camera (INCA), converted to protons, together with $\sim$28 keV to 344
MeV ion measurements from the Low Energy Charged Particle (LECP) and Cosmic Ray
Subsystem (CRS) experiments on Voyager 2, over the declining phase of Solar
Cyle 23 (SC23) and ascending phase Solar Cylce 24 (SC24) (2009-2016) to study
the characteristics of the particle energy spectrum.
  We fit the 0.11 keV to 344 MeV composite spectra with a set of regularized
isotropic $\kappa$-distribution functions (RKD) allowing the determination of
the macroscopic physical properties.
  We demonstrate that the 2009-2012 spectrum that corresponds to the declining
phase of SC23 is well fitted by three different RKDs, while the 2013-2016
spectrum, associated with the rise of SC24, can only be approximated with six
different RKDs.
  Our results are generally consistent with shock accelerated particles that
undergo additional acceleration inside the IHS. We identify a low energy
transmitted population of particles, a suprathermal reflected population and a
very high energy component that is modulated by GCRs. The 2013-2016 time period
is most likely associated with a mixture of particles from SC23 and SC24, which
is reflected by the need to employ six RDKs.
