Monitoring of AM Her urgently requested
AAVSO Alert Notice 517April 2, 2015Monitoring of AM Her urgently requested in support ofXMM-Newton and NuSTAR observations
Dr. Axel Schwope (Leibniz Institute for AstrophysicsPotsdam, Germany) has requested AAVSO observers' assistance inmonitoringthe magnetic variable AM Her in support of upcomingXMM-Newton plusNuSTAR (Nuclear Spectroscopic Telescope Array)observations.
The XMM-Newton observations are scheduled for 2015 April06 02:37:02-15:07:02 UT. The NuSTAR observations have notbeen made final yet but are expected to run longer. A SpecialNotice will be issued when the NuSTAR schedule is known.
Observers are requested to observe AM Her using standardBVRI filters (V filter preferred). The preferred manner ofobserving is to use only one filter and observe with the highestpossible time resolution (aiming for a S/N=10). Dr. Schwope writes thattiming accuracy is an issue for these observations and all CCDclocks need to be synchronized via NTP.
Observations are requested nightly from now until April4, then time series observations through April 8, and thennightly observations through April 16.
The prototype of the class of magnetic cataclysmicvariables known as polars, AM Her has "high" and"low" states, ranging approximatelyV=12.7-13.8 in its high state and V=15.3-15.7 in its lowstate. Currently it is in its high state at visual magnitude13.2 on 2015 March 30.107 UT (JD 2457111.607, G. Poyner, Birmingham,England). Its orbital period is 3.1 hours.
To learn more about polars and AM Her, see the AAVSOVariable Star of the Season web presentation "AM Herculis" (http://www.aavso.org/vsots_amher).
Coordinates:R.A.18 16 13.34 Dec. +49 52 04.1(2000.0)
Charts with a comparison star sequence for AM Her may becreatedusing the AAVSO Variable Star Plotter (VSP, http://www.aavso.org/vsp).
Please submit observations to the AAVSO InternationalDatabase using the name AM HER.
This campaign is being followed on the AAVSO ObservingCampaigns page (http://www.aavso.org/observing-campaigns).
Your filtered photometry is extremely important for theseobservations, and your contributions are greatlyappreciated.
This AAVSO Alert Notice was compiled by Elizabeth O.Waagen.
----------------------------------SUBMIT OBSERVATIONS TO THE AAVSO
Information on submitting observations to the AAVSO maybe found at:http://www.aavso.org/webobs
ALERT NOTICE ARCHIVE AND SUBSCRIPTION INFORMATION
An Alert Notice archive is available at the followingURL:http://www.aavso.org/alert-notice-archive
Subscribing and Unsubscribing may be done at thefollowing URL:http://www.aavso.org/observation-notification#alertnotices
-------------------------------------------------
頁:
[1]