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We analyze very deep IRAC and MIPS photometry of $\sim$ 12,500 members of the14 Myr old Double Cluster, h and $\chi$ Persei, building upon on our earlier,shallower Spitzer studies (Currie et al. 2007a, 2008a). Numerous likely membersshow infrared (IR) excesses at 8 {\mu}m and 24 $\mu$m indicative ofcircumstellar dust. The frequency of stars with 8 $\mu$m excess is at least 2%for our entire sample, slightly lower (higher) for B/A stars (later type,lower-mass stars). Optical spectroscopy also identifies gas in about 2% ofsystems but with no clear trend between the presence of dust and gas. Spectralenergy distribution (SED) modeling of 18 sources with detections at opticalwavelengths through MIPS 24 $\mu m$ reveals a diverse set of disk evolutionarystates, including a high fraction of transitional disks, although similar datafor all disk-bearing members would provide better constraints. We combine ourresults with those for other young clusters to study the global evolution ofdust/gas disks. For nominal cluster ages, the e-folding times ($\tau_{o}$) forthe frequency of warm dust and gas are 2.75 Myr and 1.75 Myr respectively.Assuming a revised set of ages for some clusters (e.g. Bell et al. 2013), thesetimescales increase to 5.75 and 3.75 Myr, respectively, implying asignificantly longer typical protoplanetary disk lifetime. The transitionaldisk duration, averaged over multiple evolutionary pathways, is $\sim$ 1 Myr.Finally, 24 $\mu$m excess frequencies for 4-6 M$_{\odot}$ stars appear lowerthan for 1-2.5 M$_{\odot}$ stars in other 10-30 Myr old clusters.

A Deep Spitzer Survey of Circumstellar Disks in the Young Double Cluster, h and chi Persei