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In this work, we study the shadow and photon sphere of the black bole inclouds of strings and quintessence with static and infalling sphericalaccretions. We obtain the geodesics of the photons near a black hole withdifferent impact parameters $b$. The string clouds model and quintessenceinfluence the specific intensity by affecting the geodesic and the averageradial position of photons. And the range of string clouds parameter $a$ isconstrained to ensure that the shadow can be observed. Moreover, we use a modelof the photon emissivity $j(\nu_e)$ to get the specific intensities. The lightsources in the accretion follow a normal distribution with an attenuationfactor $\gamma$. The shadow with static spherical accretion is plotted. Theapparent shape of the shadow is a perfect circle, and the value of $\gamma$affects the brightness of the photon sphere. We investigate the profile andspecific intensity of the shadows with static and infalling sphericalaccretions respectively. The interior of the shadows with an infallingspherical accretion will be darker than that with the static sphericalaccretion, and the specific intensity with both static and infalling sphericalaccretion gradually converges.

Shadow and Photon Sphere of Black Hole in Clouds of Strings and Quintessence