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Observation by Paul Leyland: Preliminary light curve of AT 2019xim ( ...

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Paul Leyland


Paul Leyland


2019 Dec 23 - 11:17


2019 Dec 25 - 11:36

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Field centre

RA: 18h59m
Dec: -62°06'
Position angle: +162°48'

Field size

4°55' × 4°00'

  • 0.4m Dilworth-Relay
  • SX Trius Pro 814
  • Johnson-V filter

308 exposures of 30 seconds each


Tacande Observatory, MPC J22

Target name

AT 2019xim


Preliminary light curve of AT 2019xim ( aka ASASSN-19ado).

About this image

A bright transient was discovered on 2019-12-22. It reached my attention via Patrick Schmeer´s baavss-alert email and, shortly afterwards, TA E3475 sent out by Guy Hurst. A request for time-resolved photometry was made. The image shows the preliminary results.

The time axis runs from HJD=2458841.3951 to HJD=2458841.5306 (i.e. 2019-12-23T21:23:47 to 2019-12-24T00:38:53).

The y-axis is the normalized flux for AT 2019xim and that for a check star which has had a value of 0.1 subtracted for clarity. The comparison used was 3784059 in the APASS catalogue (V=12.975 ±0.095) and the check star was 3784062 (V=13.781 ± 0.053).

There appears to be variability on the 20mmag scale with a hint of sinusoidal variation with a period of around 110-120 minutes.  More data and better analysis will be needed to test this hypothesis.

ATEL 13371 reports that the object is a UGWZ dwarf nova.

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