X-ray bright sources in the Chandra Small Magellanic Cloud Wing Survey - detection of two new pulsars

Abstract

We investigate the X-ray and optical properties of a sample of X-ray bright sources from the Small Magellanic Cloud (SMC) Wing Survey. We have detected two new pulsars with pulse periods of 65.8 s (CXOU J010712.6-723533) and 700 s (CXOU J010206.6-714115), and present observations of two previously known pulsars RX J0057.3-7325 (SXP101) and SAX J0103.2-7209 (SXP348). Our analysis has led to three new optical identifications for the detected pulsars. We find long-term optical periods for two of the pulsars, CXOU J010206.6-714115 and SXP101, of 267 and 21.9 d, respectively. Spectral analysis of a sub-set of the sample shows that the pulsars have harder spectra than the other sources detected. By employing a quantile-based colour-colour analysis we are able to separate the detected pulsars from the rest of the sample. Using archival catalogues we have been able to identify counterparts for the majority of the sources in our sample. Combining this with our results from the temporal analysis of the Chandra data and archival optical data, the X-ray spectral analysis, and by determining the X-ray to optical flux ratios we present preliminary classifications for the sources. In addition to the four detected pulsars, our sample includes two candidate foreground stars, 12 probable active galactic nuclei, and five unclassified sources.

13 pages, 7 figues, 4 tables, accepted for publication in MNRAS

References in corpus (22)

• High Mass X-ray Binaries as a Star Formation Rate Indicator in Distant Galaxies
• A UBVR CCD Survey of the Magellanic Clouds
• N-body Simulations of the Small Magellanic Cloud and the Magellanic Stream
• The Chandra Deep Survey of the Hubble Deep Field North Area. II. Results from the Caltech Faint Field Galaxy Redshift Survey Area
• Calibration of the MACHO Photometry Database
• Optical properties of SMC X-ray binaries
• X-ray Processing of ChaMPlane Fields: Methods and Initial Results for Selected Anti-Galactic Center Fields
• New spectral classification technique for X-ray sources: quantile analysis
• On Be Star Candidates and Possible Blue Pre-Main Sequence Objects in the Small Magellanic Cloud
• X-ray observations of Be/X-ray binaries in the SMC
• High mass X-ray binaries in the SMC: the luminosity function
• Long Period Variables detected by ISO in the SMC
• Long Term Behavior of X-ray Pulsars in the Small Magellanic Cloud
• A ROSAT PSPC X-Ray Survey of the Small Magellanic Cloud
• ROSAT HRI catalogue of X-ray sources in the SMC region
• Variability-selected quasars behind the Small Magellanic Cloud
• Three new X-ray pulsars detected in the Small Magellanic Cloud and the positions of two other known pulsars determined
• BeppoSAX and Chandra Observations of SAXJ0103.2-7209=2E0101.5-7225: a new Persistent 345s X-ray Pulsar in the SMC
• Optical counterparts to four X-ray sources in the Small Magellanic Cloud
• An X-ray investigation of the NGC 346 field in the SMC (2) : the field population
• OGLE observations of four X-ray binary pulsars in the SMC
• The binary period and outburst behaviour of the SMC X-ray binary pulsar system SXP504

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• XMM-Newton observations of the Small Magellanic Cloud: Be/X-ray binary pulsars active between October 2006 and June 2007
• Exploring the Small Magellanic Cloud to the Faintest X-ray Fluxes: Source Catalog, Timing and Spectral Analysis
• On the periodicities present in the optical light curves of SMC Be/X-ray binaries
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• Orbital Period Determinations for Four SMC Be/X-ray Binaries
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• Discovery of a 26.2 day period in the long-term X-ray light curve of SXP 1323: a very short orbital period for a long spin period pulsar
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• The Magellanic Bridge: evidence for a population of X-ray binaries
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• Properties of X-ray Binaries in the Magellanic Clouds from RXTE and Chandra Observations
• Synchrotron emission from the depths of pulsar magnetospheres