  The Isobaric Multiplet Mass Equation (IMME) has been successful at predicting
the masses of isobaric analogue states in the same multiplet, while its
coefficients are known to follow trends as functions of mass number. The Atomic
Mass Evaluation 2016 [Chin. Phys. C 41, 030003 (2017)] $^{44}$V mass value
results in an negative $c$ coefficient for the IMME quadratic term. The $b$ and
$c$ coefficients can provide constraints for construction of the
isospin-nonconserving (INC) Hamiltonians for the $pf$ shell. The excitation
energy of the $0^+, T=2$ level in $^{44}$V is currently unknown and can be used
to constrain the $^{44}$Cr mass. The aim of the experiment was to perform
high-precision mass measurements to resolve the difference between $^{44}$V
isomeric and ground states, to test the IMME, and to provide ingredients for
identifying the $0^+$, $T=2$ state in $^{44}$V. High-precision Penning trap
mass spectrometry was performed at LEBIT, to measure the cyclotron frequency
ratios of [$^{44g,m}$VO]$^+$ versus [$^{32}$SCO]$^+$, a reference mass, to
extract both the isomeric and ground state masses of $^{44}$V. The mass excess
of the ground and isomeric states in $^{44}$V were measured to be $-23\
804.9(80)$ keV/$\text{c}^2$ and $-23\ 537.0(55)$ keV/$\text{c}^2$. This yielded
a new proton separation energy of $S_p$ = 1\ 773(10) keV. The new mass values
of $^{44}$V have been used to deduce the IMME $b$ and $c$ coefficients of the
lowest $2^+$ and $6^+$ triplets in $A=44$. The $2^+$ $c$ coefficient is
verified with the IMME trend and agrees with the shell-model predictions using
charge-dependent Hamiltonians. The mirror energy differences were determined
between $^{44}$V and $^{44}$Sc, in line with isospin-symmetry. The new value of
the proton separation energy determined will be important for the determination
of the $0^+$, $T=2$ state in $^{44}$V and for prediction of the mass of
$^{44}$Cr.
