Alert Notice 705: Rare outburst of the WZ Sge star PQ And (Nova And 1988)

May 29, 2020

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Event: Rare outburst of the WZ Sge star PQ And (Nova And 1988)

Discovered by: Kenji Hirosawa (Aichi, Japan)

Discovery magnitude: 10.48 cG (using 20cmL (FL 1000mm) + CANON X9)
Discovery date: 2020 May 28.77633 UT

Coordinates (2000.0): R.A. 02 29 29.55   Decl. +40 02 40.0  (from VSX page)

Discussion: PQ And was discovered as Nova And 1988 on March 21 by D. McAdam (Telford, UK; IAUC 4570). It was presumed to be a nova (IAUC 4620) but as the spectrum was lost after initial review it was not available for additional study.

PQ And is now known to be a WZ Sge-type system (UGWZ+ZZ/GWLIB) and may be a period bouncer (Patterson et al. 2005, Publ. Astron. Soc. Pac., 117, 922). Previous outbursts were found by G. A. Richter on archival photographic plates taken in 1938 and 1967 (1990, IBVS No. 3546).

Observing recommendations: Time series are requested; the orbital period is 0.0560 d (80.6 min) so the cadence should be determined accordingly. Filtered photometry is preferred. PQ And is presently a morning target and difficult to observe, but observations made now are very important to capture superhump development.

Spectroscopy is also requested.

Observations reported to the AAVSO:
2020 Mar. 16.84030, <14.0 (E. Muyllaert, Oostende, Belgium);
19.81460, <14.5 (C. Allen, Farjestaden, Sweden);
22.85830, <14.5 (Allen);
Apr. 25.83472, <11.9 (P. Schmeer, Saarbruecken-Bischmisheim, Germany);
May. 28.77633, 10.48 cG (K. Hirosawa, Aichi, Japan; discovery (via [vsnet-alert 24302], see Note a);
29.07990, 10.3 (Muyllaert; confirmation);
29.088, 10.5 (G. Poyner, Birmingham, UK);
29.09375, 10.7 (Schmeer);

Charts: Charts with comparison stars for PQ And may be created using the AAVSO Variable Star  Plotter (VSP). Please be sure to check VSP to make certain you have the latest version.

Submit optical observations: Please submit photometry and visual observations to the AAVSO International Database using the name PQ AND.

Submit spectroscopic observations: Please submit spectroscopy reports to the AAVSO Spectroscopy Database (AVSpec).

a. Hirosawa's original discovery announcement stated the date incorrectly as 20200528.27633 in [vsnet-alert 24301].

Congratulations to Kenji Hirosawa on his discovery of this rare outburst!

This Alert Notice was compiled by Elizabeth O. Waagen.

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