Chandra ACIS Survey of M33 (ChASeM33): A First Look

Abstract

We present an overview of the Chandra ACIS Survey of M33 (ChASeM33): A Deep Survey of the Nearest Face-on Spiral Galaxy. The 1.4 Ms survey covers the galaxy out to $R \approx 18\arcmin (\approx 4$ kpc). These data provide the most intensive, high spatial resolution assessment of the X-ray source populations available for the confused inner regions of M33. Mosaic images of the ChASeM33 observations show several hundred individual X-ray sources as well as soft diffuse emission from the hot interstellar medium. Bright, extended emission surrounds the nucleus and is also seen from the giant \hii regions NGC 604 and IC 131. Fainter extended emission and numerous individual sources appear to trace the inner spiral structure. The initial source catalog, arising from $\sim$~2/3 of the expected survey data, includes 394 sources significant at the $3\sigma$ confidence level or greater, down to a limiting luminosity (absorbed) of $\sim$1.6\ergs{35} (0.35 -- 8.0 keV). The hardness ratios of the sources separate those with soft, thermal spectra such as supernova remnants from those with hard, non-thermal spectra such as X-ray binaries and background active galactic nuclei. Emission extended beyond the Chandra point spread function is evident in 23 of the 394 sources. Cross-correlation of the ChASeM33 sources against previous catalogs of X-ray sources in M33 results in matches for the vast majority of the brighter sources and shows 28 ChASeM33 sources within 10\arcsec of supernova remnants identified by prior optical and radio searches. This brings the total number of such associations to 31 out of 100 known supernova remnants in M33.

accepted for publication ApJS, full resolution images and complete tables available at http://hea-www.harvard.edu/vlp_m33_public/

References in corpus (4)

• A Survey of Local Group Galaxies Currently Forming Stars. I. UBVRI Photometry of Stars in M31 and M33
• M 33 X-7: ChASeM33 reveals the first eclipsing black hole X-ray binary
• A Catalog of Star Cluster Candidates in M33
• Spectroscopy of the brightest optical counterparts of X-ray sources in the direction of M~31 and M~33

Cited by in corpus (14)

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• A Deep XMM-Newton Survey of M33: Point Source Catalog, Source Detection and Characterization of Overlapping Fields
• The Chandra ACIS Survey of M33 (ChASeM33): Investigating the Hot Ionized Medium in NGC604
• The Chandra ACIS Survey of M33 (ChASeM33): Transient X-ray Sources Discovered in M33
• Long-term X-ray Variability of the Symbiotic System RT Cru based on Chandra Spectroscopy
• Multiwavelength Characterization of the High Mass X-ray Binary Population of M33
• A High-Resolution, Dust-Selected Molecular Cloud Catalogue of M33, the Triangulum Galaxy
• Spectroscopic Study of M33 with LAMOST survey. I. Chemical gradients from nebulae
• The Spatial Correlation of High Mass X-ray Binaries and Young Star Clusters in Nearby Star-Forming Galaxies
• X-ray Variability in the Symbiotic Binary RT Cru: Principal Component Analysis
• Monitoring the X-ray Variability of Bright X-ray Sources in M33