Unfortunately weather forecast is bad for the coming week for Belgium. Last night's observations of AR UMa after showers have been uploaded to the AAVSO International Database. Regards Josch ----- Oorspronkelijk bericht ----- Van: Axel Schwope aschwope@aip.de Aan: Taichi Kato tkato@kusastro.kyoto-u.ac.jp Cc: vsnet-alert@ooruri.kusastro.kyoto-u.ac.jp, vsnet-campaign-polar@ooruri.kusastro.kyoto-u.ac.jp Verzonden: Sat, 06 May 2023 11:16:39 +0200 (CEST) Onderwerp: [vsnet-alert 27722] Re: AR UMa short-term variations

Triggered high state XMM-Newton observations of AR UMa are scheduled for the date below. Contemporaneous high-cadence photometry in either BVR or I filters is highly appreciated.

Proposal Obs. Target Name Status Rev. Start Time -------- ----- -------------------- ----------- ----- ------------------- 088487 01 01 AR UMa Scheduled 4288 2023-05-09T20:31:40

Am 06.05.2023 um 02:14 schrieb Taichi Kato tkato@kusastro.kyoto-u.ac.jp:

AR UMa short-term variations

Josch Hambsch reported time-resolved observations. In addition to the expected orbital modulation (0.7 mag), QPO-like variations were also recorded, which are often observed in polars.

— —————————————————————— Axel Schwope Galaxies and Quasars / Head X-ray astronomy

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