Table · dataset · 2023
Rotation and spots in normal A and Am/Fm stars
Listed in IVOA Registry (Virtual Observatory)
Frequency analysis of long-term ultraprecise photometry can lead to precise values of rotation frequencies of rotating stars with 'hump and spike' features in their periodograms.
Description
Using these features, we computed the rotation frequencies and amplitudes. The corresponding equatorial rotational velocity (V_rot_) and spot size were estimated.
On fitting the autocorrelation functions of the light curves with the appropriate model, we determined the star-spot decay time-scale. The V_rot_ agrees well with the projected rotational velocity (vsini) in the literature. Considering a single circular and black spot, we estimate its radius from the amplitude of the 'spike'.
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No evidence for a significant difference in the average 'spike' amplitude and spot radius was found for Am/Fm and normal A stars. Indeed, we derived an average value of ~21+/-2 and ~19+/-2ppm for the photometric amplitude and of 1.01+/-0.13 and 1.16+/-0.12R_E_ for the spot radius (where R_E_ is the Earth radius), respectively. We do find a significant difference for the average spot decay time-scale, which amounts to 3.6+/-0.2 and 1.5+/-0.2d for Am/Fm and normal A stars, respectively.
In general, spots on normal A stars are similar in size to those on Am/Fm stars, and both are weaker than previously estimated. The existence of the 'spikes' in the frequency spectra may not be strongly dependent on the appearance of star-spots on the stellar surface. In comparison with G, K, and M stars, spots in normal A and Am/Fm stars are weak, which may indicate the presence of a weak magnetic field.
Links
Where it is published
- Reference page cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/492/3143 ↗
landing page · from IVOA Registry
Documentation and papers
- ADS 2020MNRAS.492.3143T ui.adsabs.harvard.edu/abs/2020MNRAS.492.3143T ↗
publication · from IVOA Registry
Catalogue records · 2
- VOResource record dc.g-vo.org/oai.xml?verb=GetRecord&metadataPrefix=ivo_vor&identifier=ivo%3… ↗
metadata API · from IVOA Registry
- Registry record (GAVO) dc.g-vo.org/I/cds.vizier/j/mnras/492/3143 ↗
catalogue entry · from IVOA Registry
Topics
- Stated by source
- Optical
- From keywords
- Astronomy & Astrophysics
Provenance · 1 source records, 8 field assertions
| Source | Key | Last seen | Raw |
|---|---|---|---|
| IVOA Registry (Virtual Observatory) | ivo://cds.vizier/j/mnras/492/3143 | 12 d ago | JSON v1 |
| Field | Assertion | Extractor | Evidence |
|---|---|---|---|
| access_level | source · IVOA Registry | connector:ivoa_registry@1.0.0 | |
| concepts[field].local:field:astronomy | mapping · IVOA Registry | connector:ivoa_registry@1.0.0 | |
| concepts[modality].ivoa_waveband:optical | source · IVOA Registry | connector:ivoa_registry@1.0.0 | |
| description | source · IVOA Registry | connector:ivoa_registry@1.0.0 | rr.resource.res_description |
| license_text | source · IVOA Registry | connector:ivoa_registry@1.0.0 | |
| publication_date | source · IVOA Registry | connector:ivoa_registry@1.0.0 | |
| title | source · IVOA Registry | connector:ivoa_registry@1.0.0 | rr.resource.res_title |
| updated_date | source · IVOA Registry | connector:ivoa_registry@1.0.0 |