Short Period Pulsators (SPP)

For those of you who are familiar with AstroImageJ (AIJ), a capability has been added to the latest daily build that allows the user to create a variable star report that conforms with the AAVSO International Database (AID) format for both single comparison stars, as well as for an ensemble of comparison stars. I want to thank Ken Menzies and others who have helped with the testing.

AAVSO Alert Notice 786 announces an observing campaign on the RR Lyr star V338 Boo. Please see the notice for details and observing instructions.

There are threads for this campaign under the following forums:

- Campaigns and Observing Reports: https://www.aavso.org/v-338-boo-campaign-2022
- Short Period Pulsators (SPP): https://www.aavso.org/v-338-boo-campaign-2022-01

I'm not sure whether this is the correct forum for this question, but Eps Cep is a SPP (a Delta Scuti), so here goes... please note that I am new to photometry and am just trying to practice on some well-known variables, the eventual goal being to study exoplanet transits.

I see in the June newsletter about the SPP section: "Gathering observations in M13, as well as the “Legacy Stars,” so lots of data is expected to be collected over the next few months."  I've not heard anything about this but might be interested in contributing.  Are there more details to be had?

Richard

AAVSO Alert Notice 777 announces an observing campaign beginning immediately on the delta Sct variable EH Lib. Observations are critical now through at least the night of June 09/10. Please see the notice for details and instructions.

There are threads for this campaign under the following forums:

Following Dr Riess's suggestion in Saturday's webinar that a valuable contribution amateurs can make to the improvement of the Hubble 'constant' and the expansion rate/change of the universe would be to observe long period Cepheids I did a search in the fabulous VSX for DCEP with periods > 5d (and located north of -20d as I live in southern Canada, and south of +55 for the trees along my northern 'horizon') and I find that most of the stars are quite bright.

Hi,

What is the correct mathematical or physically method of determining the maximum of Delta-Scuti-Stars or HADS?

If I take the wohle lightcurve I get other results as I only take half of the lightcurve. Some collegues told me, only to take half of the LC, but is that only an opinion, or is there a physically proof somewhere?

• Does one take the whole LC, from the plateou (blue lines)?
• Does one take the whole LC, but only from ascent to descent?
• Does one take oly half of the LC (green line)

Bernhard

Hi,

DY PEG was one of my first observations. I have made a mistake with my first upload, I have submitted 2458721  with the false time. (1 hour corrected too much)

Now I have now uploaded the (+1h) corrected dataset. Some people have downloaded my false data from 2458721. 

(I became aware of this with actual DY PEG data, where the O-C was much different as from JD 2458721...  )

NOW:

Epoche    C                    O (WBEA)            O-C

I measured this high amplitude del Scu star during February and March with my 500mm refractor and Canon 450D. 
I calculated the two periods (first and second overtone of the radial pulsation) using VSTAR in good agreement with published literature data.

P1 = 0.17835 (0.17836, Cox. et al)
P2 = 0.14279 (0.14280)

Analysis of the amplitudes shows a strong variation with a mean of 0.501 and a standard deviation of 0.128

Data uploaded to the AAVSO database.

Hello! Just looking over my curves for DY HER and SZ HYA. B-V seems to narrow at minimum compared to maximum for these two stars.

    Is this a common feature of SPVs? Thank you and best regards.

Mike