IP Catalog Update No. 1

The IP Catalog Version 2008a, released on 2008 July 8, contains the folloing changes compared with Version 2007a.

SAX J1748.2-2808 is shown to have a 594 s period, and a three-component Fe Kalpha complex. Thus, I consider this to be a "probable" IP.
Not much is yet known about V2491 Cyg (Nova Cygni 2008 No. 2) in quiescence, beyond the fact that it was detected in X-rays, including above 10 keV. This fact alone merits the status as a "possible" IP. However, a massive, non-magnetic white dwarf is another possible interpretation. T CrB, a recurrent nova in a symbiotic binary, is a known Swift BAT source; the optical spectra of V2491 Cyg have similarities to recurrent novae of non-symbiotic type. Regardless of the nature of the mass donor, recurrent novae are believed to harbor a near Chandrasekhar-mass white dwarf.
Three objects detected above 10 keV and optically identified with CVs, Swift J052522.48+241331.8, Swift J061223.0+701243.9, and 1ES 1210-646. Based on these facts alone, they are candidate IPs at some level. The two Swift objects are described as "transients" which needs an explanation - I've classified them as "possible." 1ES 1210-646 is also cataloged as a SAX WFC source at a flux level that is extremely high for an IP. Therefore, I have classified it as "doubtful" for the time being.

Butters et al. (2008) report the RXTE observations of three candidates. Of these, the X-ray detection of the 465.68 s period (previously seen in the optical) raises the status of XSS J00564+4548 from "probable" to "confirmed." The observations were not conclusive for the two other targets, I've raised The two other targets, XSS J12270-4859 and IGR J17195-4100, but I've raised their status from "possible" to "probable" weighing all the evidence together.
Anzolin et al. have submitted a paper to A&A describing XMM-Newton and optical observations of 1RXS J070407.9+262501 and 1RXS J180340.0+401214. They are both confirmed as IPs (from "probable"). In addition, the orbital period of latter has been corrected to 4.402 hrs.
I've also raised the status of V2487 Oph from "doubtful" to "possible," having seen a poster paper by Ferri et al. describing additional XMM-Newton data. However, see also my comment above on V2491 Cyg.

Please send your comments, suggestions etc. to Koji.Mukai@nasa.gov and/or Koji.Mukai@umbc.edu

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