Photometry requested for HD 98800 (TV Crt)
Abstract:
Michael Poxon (AAVSO YSO SIG leader) writes: Photometry over at least the following 12 months of the TV Crateris system (approx magnitude 9 visual) as one close pair of young stars is eclipsed by the distorted circumstellar disc of the other pair in the system. NOTE: This campaign has been revised as follows: Periastron will occur in 2025, NOT 2026 as originally stated. The cadence of observations is changed to 3 observations per night beginning immediately and continuing through periastron. After periastron one observation per night will be sufficient.
Justification:
Photometry of the light variations of the system could enable details of the circumstellar disc's structure in which planets are probably forming to be refined. Since the system is quite bright it may even be a target for amateur spectroscopists, although spectroscopy is not specifically requested for this campaign.
Requested Data Types:
Photometry
Targets
| Name | Magnitude | Variability Type | Photometry Notes | Spectroscopy Notes |
|---|---|---|---|---|
| TV Crt | 8.82 | TTS/ROT+E-DO |
Cadence: Custom Precision: 100 |
Not Requested |
Spectroscopy Lines:
No spectroscopy lines provided
Photometry Filters:
B (Johnson), V (Johnson), R (Cousins), I (Cousins), g (Sloan), r (Sloan), i (Sloan), Other (Please Specify)
Comparison Stars:
Finder charts with comparison stars are available via the AAVSO Variable Star Plotter (VSP, https://apps.aavso.org/vsp/).
Co-Authorship
Observers are not eligible for co-authorship.
Additional Observer Input:
Text revised: TV Crt is probably not suitable for visual observation due to quite low amplitude. Periastron will occur in 2025, NOT 2026 as originally stated. Beginning immediately, 3 photometric observations per night are requested (see filter list above, CR also useful) - this is when the multicolor photometry is most important. After periastron, one data point per night per filter is requested. B and R are first priority, then I, then V; variations in V are not expected to be substantial, so V is of lowest priority and CV is not particularly recommended. For more information as periastron approaches, please keep watching the forum created for this campaign.
Additional Submission Location:
Not provided
Forum URL
https://forums.aavso.org/t/observing-campaign-893-photometry-requested-for-hd-98800-tv-crt/2422
Notes:
For more information about the TV Crt system and this campaign, please see the April 2025 issue of the YSO Bulletin (https://www.starman.co.uk/ysosection/newsletters/apr2025.html).