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We present mid-infrared Spitzer IRAC and MIPS images of the UX Orionis starVV Ser and the surrounding cloud. The 5.6--70 micron images show bright,localized and nebulous emission extended over 4 arcmin centered on VV Ser. Weinterpret the nebulosity as being due to transiently heated grains excited byUV photons emitted by VV Ser. A companion paper describes how the physicalstructure of the VV Ser disk has been constrained using a wide range ofobservational data modeled by an axisymmetric Monte Carlo radiative transfercode. In this paper we employ the model to study the nebulosity surrounding VVSer using quantum-heated PAH molecules and Very Small Grains (VSGs) consistingof amorphous carbon in the thermal cooling approximation. Imprinted on thenebulosity is a wedge-shaped dark band, centered on the star. We interpret thisdark wedge as the shadow cast by the inner regions of a near-edge-on disk in UVlight, allowing the PAHs to be excited only outside of this shadow. Thepresence of a disk shadow strongly constrains the inclination as well as theposition angle of the disk. Although depending on the adopted PAH opacity, theabundance of PAHs in the surrounding cloud is constrained to 5+/-2% of thetotal dust mass, given the opacity. The extent of the nebulosity constrains thedensity of the gas surrounding the VV Ser disk to 500+/-200 cm-3 for agas-to-dust ratio of 100. This low density suggests that the quantum heatedmaterial is not part of the original envelope of VV Ser and that it is rather aquiescent part of the Serpens molecular cloud that the star has passed intoafter being formed. [Abstract abridged]Comment: 11 pages, accepted for publication in Ap

ModelingSpitzerObservations of VV Ser. II. An Extended Quantum‐heated Nebula and a Disk Shadow