Divertor heat flux profiles in negative triangularity DIII-D discharges*

L-mode discharges with negative upper triangularity ($\delta_u$) shape in DIII-D exhibited wider scrape-off layer (SOL) power fall off lengths ($\lambda_q$) compared to H-mode discharges with similar shaping. Lower single null diverted discharges with negative upper triangularity and near zero lower triangularity were developed in DIII-D at plasma current $I_p$=900kA with neutral beam ($P_{NBI}$=4-13MW) and electron cyclotron heating ($P_{ECH}$=1.5 MW). SOL power fall-off lengths were derived from upstream Thomson scattering profiles and divertor infrared thermography. The inter-ELM $\lambda_q$ measured in a negative upper triangularity ($\delta_u\sim$-0.2) H-mode discharge was comparable with those measured in H-mode discharges with positive $\delta_u$. The SOL power fall off length in L-mode discharges with $\delta_u \sim$-0.4 was up to 50$\%$ larger than in the similarly-shaped H-mode plasma. $\lambda_q$ in negative triangularity L-mode discharges was reduced when compared to L-mode plasmas in positive triangularity at lower injected power and to multi-machine L-mode scaling. 2D transport modeling with the SOLPS-ITER code is underway to estimate the change in edge transport coefficients between negative triangularity L and H-mode discharges and their effect on divertor plasma.