published, but the study is early or one-sided: only part of the Kepler data, or no spectroscopy of its own
| reference | Reed et al. 2012, MNRAS 427, 1245 |
| title | The discovery of two pulsating subdwarf B stars in NGC 6791 using Kepler |
| Kepler data used | one month of short cadence, one star per month |
| atmospheric parameters | B3 = KIC 2569576, Kp 17.801, Teff 24250 +- 459 K, log g 5.17 +- 0.05, log N(He)/N(H) -2.81 +- 0.12 |
| the spectrum behind it | Reed et al. obtained ALFOSC spectra at the NOT in 2012 May; the B3 extractions from both nights are here, and their mean. |
| as a reference object | no At Kp ~18 in a crowded cluster field these are the faintest stars in the project; the spectra reach S/N 27-55 and are not good reference objects for spectroscopy. They are here for completeness. |
| note | A discovery paper on one month of data. The same paper also gives B6 = KIC 2569583 (Kp 17.660, 37008 +- 539 K, log g 5.72 +- 0.06, -2.69 +- 0.24), which is not in this target list; its spectra are in data/spek/NGC6791. |
Paper: Reed12b.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 |
|---|---|---|---|---|---|---|---|---|---|---|
| NOT ★ | NOT / ALFOSC_FASU | 2012-05-14 | 2 | 54.9 | 4.50 | 24845 ± 336 | 5.356 ± 0.050 | -2.64 ± 0.11 | 2.86% | 1.68 |
| NOT-1 | NOT / ALFOSC_FASU | 2012-05-14 | 1 | 26.8 | 4.50 | 23613 ± 752 | 5.256 ± 0.099 | -2.78 ± 0.26 | 4.74% | 1.16 |
| NOT-2 | NOT / ALFOSC_FASU | 2012-05-30 | 1 | 38.2 | 4.50 | 25306 ± 463 | 5.400 ± 0.071 | -2.51 ± 0.16 | 3.76% | 1.28 |
★ 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 lower-case directories (b3/, b3-1/, b3-2/, b4/, b5/) are copies of the 2012 fitprof22 working directories from data/spek/NGC6791, kept as they were run, each with the line list of its own era. None holds an sp.spek, so fitk1 does not read them. The live directories are NOT/ (and NOT-1/, NOT-2/ for Fredegar), extracted from the same FITS and linked to the master. All five spectra are NOT/ALFOSC Grism #16 through a 1.0in slit, so they share one resolution: 4.50 A, the value the 2012 fits used. Ca II K cannot supply it here -- at S/N 25-55 the line is only 6-16% deep and its measured width scatters from 1.9 to 4.1 A between spectra of the same field. Two stars share each slit: b3b6 (Fredegar and B6) and b4b5 (Adamanta and Adelard). The header RA/DEC is the slit centre, not the star, and B6 is not one of the nineteen -- its spectra stay in data/spek/NGC6791.