The Chandra Multiwavelength Project:Galactic Plane Survey Chandra X-ray Observatory National Optical Astronomy Observatory

The ChaMPlane survey is being conducted at the Harvard-Smithsonian Center for Astrophysics.

NOAO Long Term Survey

ChaMPlane is approved as an NOAO Long Term Survey (5 year) project to conduct the optical identification survey for ChaMPlane sources with a deep imaging survey using the NOAO 4-m telescopes at CTIO (5 nights/year) and KPNO (1 night/year). The target fields are selected using the Selection Criteria and are observed with the MOSAIC imager (36' x36'), so that the entire Chandra ACIS-I (or ACIS-S) field is covered. The NOAO optical survey for ChaMPlane will be the deepest H-alpha survey of portions of the galactic plane, and will cover ~ 4 x the area of the enclosed Chandra ChaMPlane survey for which it will provide the primary identifications.

The ChaMPlane NOAO imaging survey serves two purposes:

1) provide images for identifying the optical counterparts of Chandara sources and measure their V, R, I, H-alpha magnitudes to enable approximate spectral classification and constraints on reddening

2) identify H-alpha emission objects (by comparison of their magnitudes in H-alpha vs. R filters) as well as to measure their V, R, and I magnitudes. Deep (R ~ 24) 4-m Mosaic images are obtained to identify CVs and qLMXBs by their ubiquitous H-alpha excess as ``blue'' objects in the R vs. (H-alpha - R) diagram. We have successfully conducted the ChaMPlane survey for the first year and obtained deep images in the V, R, I and H-alpha bands for 21 Chandra fields (17 from CTIO and 4 from KPNO).

The NOAO Survey will eventually include ~100 fields (MOSAIC) near the galactic plane, or about 36 square degrees. Some 21 fields have been observed thus far (in first 1.5 year of ChaMPlane) as listed in the Early Results table.