RX J1914+24: The first double degenerate polar to be discovered?

RX J1914+24 was discovered during the ROSAT all sky survey and was found to show an X-ray period of 9.5 mins (569 sec). At MSSL we obtained followup ROSAT observations and found that for half of this 9.5 min period the X-ray flux was consistent with zero. We concluded that this period was the spin period of an accreting object (a white dwarf) and also the orbital period of the binary. With an orbital period this short the donor star could not be a late type main sequence star, (as in the case of a CV), but it could be a white dwarf star. In other words we suggested the object was a double degenerate binary, where both the primary and secondary stars are white dwarfs.

In the various papers mentioned on the previous page we detail our observations and reasons why we think that RX J1914+24 is a double degenerate polar. Recently we have obtained a series of J band images taken by Kaz Sekiguchi using the 8m SUBARU telescope in Hawaii which we show below. This is the image made from all the 5 sec exposures and totals around 1hr of data. Cool or what! Stars A (V=15.5) and B (V=17.6) are separated by 7 arc sec. The optical counterpart of RX J1914+24 (V=19.9, J=17.3) has a position of 19^h 14^m 26.11^s +24^o 56^' 43.6^" (2000.0) with an error of 0.4^". It is consistent with the X-ray position (Ramsay et al, in prep). This image is probably one of the deepest ever images obtained in the J band. Even in the reproduction below many faint sources are visible - probably very faint stars or distant galaxies.

This page was compiled by Gavin Ramsay (gtbr@mssl.ucl.ac.uk) and last up dated on 1 Nov 1999.