Chandra Multiwavelength Plane (ChaMPlane) Survey: Results from the First Year

Ping Zhao, Jonathan E. Grindlay, Peter Edmonds, Michael R. Garcia, Jeffrey E. McClintock (CfA), Haldan Cohn, Phyllis Lugger, Shawn Slavin (Indiana U.), Don W. Hoard & Stefanie Wachter (CTIO)


The Chandra Multiwavelength Plane (ChaMPlane) Survey is a project to identify a large sample of serendipitous X-ray sources in the galactic plane ( $\bf \vert b\vert \lesssim 10^{\circ}$), including cataclysmic variables (CVs), quiescent low mass X-ray binaries (qLMXBs: which includes both black hole and neutron star systems), Be X-ray binaries and stellar coronal sources (see Grindlay et al 2000, BAAS, 196, 37.07 for general description). The major goal is to measure, or constrain, the luminosity functions of compact X-ray binaries and CVs. The ChaMPlane project is currently supported by NASA (Chandra Archive), NOAO, and NSF. ChaMPlane has been chosen by NOAO as a Long Term Survey Program. Deep ( $\bf R \sim 24$) 4m Mosaic images are obtained to identify CVs and qLMXBs by their ubiquitous $\bf H\alpha$ excess as ``blue'' objects in the R vs. $\bf (H\alpha - R)$ diagram. We have successfully conducted the ChaMPlane survey for the first year and obtained: deep images in the V, R, I and $\bf H\alpha$ bands for 21 Chandra fields (17 from CTIO and 4 from KPNO); corresponding serendipitous X-ray source fluxes from archived Chandra (AO1) fields; optical WIYN/Hydra multi-fiber spectra and Magellan/LDSS2 multi-slit spectra for the X-ray sources and detected $\bf H\alpha$-excess sources in three Chandra fields (J0422+32, A0620-00 and SgrA*). We present our data analysis methods and photometry, spectroscopy and X-ray results from the first year of the ChaMPlane Survey.



Himel Ghosh