Joint Likelihood study of Crab pulsar wind nebula with VERITAS and HAWC

The Crab Pulsar Wind Nebula (PWN) has been generally considered a steady source in the fields of high-energy and very-high-energy astronomy. The Fermi-LAT and AGILE satellites detected Crab PWN flux variations, questioning the steadiness of the Crab PWN emission. Significant flux variability has been observed in the MeV energy regime, whereas only marginal flux variability has been observed in the GeV energy regime. However, no variability has been detected in the TeV energy regime. Several viable models have been proposed to explain this behavior. To constrain these models, more sensitive observations of the Crab PWN are needed.The HAWC and VERITAS gamma-ray observatories have observed the Crab PWN at energies greater than very-high-energies (E > 100 GeV), and have already published independent spectral measurements from each instrument. However, jointly these two instruments are able to cover the extended energy range from 100 GeV to 100 TeV. In addition, a joint Crab PWN observation ismore sensitive than the observation of either independent instrument. This presentation reports on the progress of the ongoing VERITAS-HAWC joint likelihood study of the Crab PWN energy spectrum. This presentation will also report on the use of simultaneous observations of the Crab PWN to cross-calibrate the energy scale and detection aperture of the two observatories.