Alert Notice 804: RW Cep dimming underway - observations requested
Active Dates: Dec. 16, 2022 – Dec. 31, 2024
Abstract:
The bright semiregular variable RW Cep is undergoing an episode of apparent dimming, and observations of all types are requested. Multicolor photometry (all filters), visual observations, and spectroscopy will be valuable in documenting and interpreting this event.
Justification:
Visual and multicolor photometry observations in the AAVSO International Database since 1935 show previous occasions when RW Cep reached magnitudes similar to its current value. The current event appears to be a combination of past shifts and minima. Documenting it will help to understand these patterns.
Requested Data Types:
Spectroscopy, Photometry
Targets
| Name | Magnitude | Variability Type | Photometry Notes | Spectroscopy Notes |
|---|---|---|---|---|
| RW Cep | 6.00 | SRD |
Cadence: Nightly Precision: 100 |
Cadence: Nightly Resolution: 250 Desired SNR: 100 |
Spectroscopy Lines:
No spectroscopy lines provided
Photometry Filters:
B (Johnson), V (Johnson), R (Cousins), I (Cousins), Other (Please Specify)
Comparison Stars:
Finder charts with comparison stars may be created using the AAVSO Variable Star Plotter (VSP, https://apps.aavso.org/vsp/).
Co-Authorship
Observers are not eligible for co-authorship.
Additional Observer Input:
Observations should begin now and continue until further notice. Time series observations are not requested; other photometry and visual observations are requested at a rate of once per week at this time. If a change in cadence is warranted, it will be announced in the forum threads above. Visual observers need to be aware of the redness of RW Cep and make observations using the quick-glance method, rather than looking at the variable for prolonged periods.
Additional Submission Location:
none
Forum URL
Notes:
Principal Investigator: Elizabeth O. Waagen; Imported Campaign (Alert Notice #804). Other photometric filter = visual observations. Forum url given below is in the Campaigns and Observation Reports forum. There is also a forum thread here: Long Period Variables: https://www.aavso.org/rw-cep-dimming-01