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We have identified 17 A-type stars in the Galactic Plane that have mid-IRexcesses at 8 micron. From the observed colors in the (r'-H_alpha)-(r'-i')plane, we first identified 23050 early A-type main sequence (MS) starcandidates in the Isaac Newton Photometric H-Alpha Survey (IPHAS) point sourcedatabase that are located in Spitzer GLIMPSE Galactic Plane fields. Imposingthe requirement that they be detected in all seven 2MASS and IRAC bands led toa sample of 2692 candidate A-type stars with fully sampled 0.6 to 8 micronSEDs. Optical classification spectra of 18 of the IPHAS candidate A-type MSstars showed that all but one could be well fitted using main sequence A-typetemplates, with the other being an A-type supergiant. Out of the 2692 A-typecandidates 17 (0.6%) were found to have 8-micron excesses above the expectedphotospheric values. Taking into account non-A-Type contamination estimates,the 8-micron excess fraction is adjusted to ~0.7%. The distances to thesesources range from 0.7-2.5 kpc. Only 10 out of the 17 excess stars had beencovered by Spitzer MIPSGAL survey fields, of which 5 had detectable excesses at24 micron. For sources with excesses detected in at least two mid-IR wavelengthbands, blackbody fits to the excess SEDs yielded temperatures ranging from 270to 650 K, and bolometric luminosity ratios L_IR/L* from2.2x10^{-3}-1.9x10^{-2}, with a mean value of 7.9x10^{-3} (these bolometricluminosities are lower limits as cold dust is not detectable by this survey).Both the presence of mid-IR excesses and the derived bolometric luminosityratios are consistent with many of these systems being in the planet-buildingtransition phase between the early protoplanetary disk phase and the laterdebris disk phase.

IPHAS A-type Stars with Mid-IR Excesses in Spitzer Surveys