  We have explored the thermodynamics of compressed magnetized plasmas in
laboratory experiments and we call these studies "magnetothermodynamics". The
experiments are carried out in the Swarthmore Spheromak eXperiment device. In
this device, a magnetized plasma source is located at one end and at the other
end, a closed conducting can is installed. We generate parcels of magnetized
plasma and observe their compression against the end wall of the conducting
cylinder. The plasma parameters such as plasma density, temperature, and
magnetic field are measured during compression using HeNe laser interferometry,
ion Doppler spectroscopy and a linear $\dot{B}$ probe array, respectively. To
identify the instances of ion heating during compression, a PV diagram is
constructed using measured density, temperature, and a proxy for the volume of
the magnetized plasma. Different equations of state are analyzed to evaluate
the adiabatic nature of the compressed plasma. A 3D resistive
magnetohydrodynamic code (NIMROD) is employed to simulate the twisted Taylor
states and show stagnation against the end wall of the closed conducting can.
The simulation results are consistent to what we observe in our experiments.
