published, but the study is early or one-sided: only part of the Kepler data, or no spectroscopy of its own
Worth checking for better spectra. The published values are KepI's, from a low-resolution classification spectrum, and their errors say as much: +- 800 K and +- 0.13 dex. Held here is a mean of 25 WHT ISIS spectra from 2010, which is much better -- and is why the Bamberg log g here, 5.475 +- 0.011, sits 0.34 dex above the published 5.14, the largest such gap in the sample. Pablo et al. (2012) was published early and may not have waited for the updated spectroscopy -- CHECK with J. H. Telting and M. D. Reed whether this star was included in the spectroscopic survey.
| reference | Pablo et al. 2012, MNRAS 422, 1343; Baran 2012, AcA 62 |
| title | Seismic evidence for non-synchronization in two close sdB+dM binaries from Kepler photometry |
| Kepler data used | nine months, quarters Q5 to Q8 |
| pulsations | High-overtone g modes with a clear sequence of equal period spacings, plus several periodicities that depart from that trend -- a cleaner pattern than its companion star in the same paper. Rotational splitting again shows the sdB rotating far too slowly for synchronisation |
| orbit | Inclination less than about 8.5 deg; companion mass below 0.26 Msun from the tidal argument |
| atmospheric parameters | Teff 26000 +- 800 K, log g 5.14 +- 0.13, quoted from Ostensen et al. (2010) -- the paper carries no spectroscopy of its own |
| the spectrum behind it | The published values are KepI's, from a low-resolution classification spectrum, and their errors say as much: +- 800 K and +- 0.13 dex. Held here is a mean of 25 WHT ISIS spectra from 2010, which is much better -- and is why the Bamberg log g here, 5.475 +- 0.011, sits 0.34 dex above the published 5.14, the largest such gap in the sample. Pablo et al. (2012) was published early and may not have waited for the updated spectroscopy -- CHECK with J. H. Telting and M. D. Reed whether this star was included in the spectroscopic survey. |
| note | A photometric study, sharing its paper with Merry. Its non-synchronisation result bears directly on the Toby project. |
Paper: Pablo12.pdf, in /home/roy/sync/old/sddoc.
| observation | telescope | date | n | S/N | FWHM [Å] | Teff [K] | log g | log n(He)/n(H) | residual | χ² |
|---|---|---|---|---|---|---|---|---|---|---|
| WHT ★ | WHT / ISIS blue arm | 2010-07-02 | 25 | 228.1 | 1.75 | 26856 ± 59 | 5.475 ± 0.011 | -2.63 ± 0.03 | 0.91% | 1.83 |
★ marks the observation adopted for the sample table — the one with the smallest residual, which is what says how well the model reproduces the spectrum. Signal-to-noise does not.
The line fit gives a temperature and a gravity but says nothing about size. Held at those parameters, the broadband spectral energy distribution has one free scale — the angular diameter — and the Gaia parallax turns that into a radius. Then M = gR²/G, which is linear in g: a tenth of a dex in gravity is 26 per cent in mass, so this is where the gravity scale bites hardest.
Treat this fit with care. parallax +-42%. The numbers below are what the photometry gives; these are the reasons it may not be giving much.
| distance [pc] | 5838 |
| parallax error [%] | 41.7 (per cent; the mass error is twice this) |
| E(44−55) [mag] | 0.086 (0.058–0.112) |
| … the dust map | 0.0486 (SFD×disk(f=1.00)) |
| log Θ [rad] | -11.633 +0.016 −0.017 |
| R [R☉] | 0.300 +0.207 −0.088 |
| M [M☉] | 0.984 +1.829 −0.499 |
| L [L☉] | 42.3 +78.3 −21.3 |
Bamberg v25 ATLAS12 through the real filter curves, reddened by Fitzpatrick (1999) — its A(5500)/E(B−V) is 3.03, so this E(B−V) and the E(44−55) of Heber's group are the same number to under one per cent. Prescribed at 26856 K and log g 5.475 from WHT, with 15 of the fitted bands and reduced χ² 0.38. The gravity error carried into the mass is 0.050 dex — the scatter between telescopes, not the formal error, because the formal one would claim a two per cent mass.
Bands left out: Johnson:B, GALEX:NUV, GALEX:FUV, GAIA/GAIA3:G, GAIA/GAIA3:Gbp, GAIA/GAIA3:Grp, SDSS:u, SDSS:g, SDSS:r, SDSS:i, SDSS:z, SDSS:u/SDSS:u', SDSS:g/SDSS:g', SDSS:r/SDSS:r', SDSS:i/SDSS:i', SDSS:z/SDSS:z', Johnson:U, Johnson:V, Cousins:U.
wht/ is the original 2021 fitprof22 working directory, kept as it was run; its chidel.dat is the line list of that era, recovered from /home/roy/sync/targets/Merry/WHT/chidel.dat, which reproduces all sixteen of its fitted lines exactly. It holds no sp.spek, so fitk1 does not read it. The live directory is WHT/, extracted from the same meanall.fits and linked to the master.