Short Period Pulsators (SPP)

Forum Topics Posts Last post
No new posts

Information on the Observation and analysis of short period pulsators such as Cepheids and RR Lyrae.

26 123 By gilchrist.alle… 8 hours 35 minutes ago

AstroImageJ now supports generation of variable star reports

Affiliation
American Association of Variable Star Observers (AAVSO)
dennis-conti Mon, 10/03/2022 - 17:06

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.

V338 Boo campaign - Alert Notice 786

Affiliation
American Association of Variable Star Observers (AAVSO)
weo Tue, 07/12/2022 - 14:59

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

Question about Epsilon Cephei

Affiliation
American Association of Variable Star Observers (AAVSO)
Elisabeth Atems Thu, 07/07/2022 - 18:50

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.

Gathering observations in M13?

Richard Wagner Sun, 06/12/2022 - 20:41

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

EH Lib observations needed now - Alert Notice 777

Affiliation
American Association of Variable Star Observers (AAVSO)
weo Mon, 06/06/2022 - 21:32

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:

Galactic Cepheids for Cosmology - re Dr Riess's Recommendation

Richard Wagner Sun, 05/29/2022 - 21:21

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.

Correct Maximum determination of DSCT's or HADS?

Affiliation
Bundesdeutsche Arbeitsgemeinschaft fur Veranderliche Sterne e.V.(Germany) (BAV)
Bernhard Fri, 04/01/2022 - 11:58

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

DY PEG from JD 2458721 corrected

Affiliation
Bundesdeutsche Arbeitsgemeinschaft fur Veranderliche Sterne e.V.(Germany) (BAV)
Bernhard Thu, 07/29/2021 - 12:22

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

VZ Cnc observations Feb_Mar 2021

Affiliation
Bundesdeutsche Arbeitsgemeinschaft fur Veranderliche Sterne e.V.(Germany) (BAV)
MatthiasK Wed, 04/07/2021 - 17:35

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.