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We simulate transverse oscillations in radiatively cooling coronal loops andforward-model their spectroscopic and imaging signatures, paying attention tothe influence of background emission. The transverse oscillations are driven atone footpoint by a periodic velocity driver. A standing kink wave issubsequently formed and the loop cross-section is deformed due to theKelvin-Helmholtz instability, resulting in energy dissipation and heating atsmall scales. Besides the transverse motions, a long-period longitudinal flowis also generated due to the ponderomotive force induced slow wave. We thentransform the simulated straight loop to a semi-torus loop and forward-modeltheir spectrometer and imaging emissions, mimicking observations of Hinode/EISand SDO/AIA. We find that the oscillation amplitudes of the intensity aredifferent at different slit positions, but are roughly the same in differentspectral lines or channels. X-t diagrams of both the Doppler velocity and theDoppler width show periodic signals. We also find that the background emissiondramatically decreases the Doppler velocity, making the estimated kineticenergy two orders of magnitude smaller than the real value. Our results showthat background subtraction can help recover the real oscillation velocity.These results are helpful for further understanding transverse oscillations incoronal loops and their observational signatures. However, they cast doubt onthe spectroscopically estimated energy content of transverse waves using theDoppler velocity.

Forward Modeling of Simulated Transverse Oscillations in Coronal Loops and the Influence of Background Emission