J21589+2124sdB

SDSSJ215854.10+212432.5  ·  21:58:54.12 21:24:32.58  ·  Culpan knownhsd

χ²/N = 1.00

Spectrum

shaded: the intervals the fit used ·  │ a cancelled pixeldrag on either panel to zoom · dbl-click or Esc to reset · arrows to pan

The whole reduced spectrum above, the region marked on it below. Shaded bands are the intervals the fit used; a tick under the axis marks a pixel the rejection mask cancelled.

Line-profile fit — Bamberg

profile fit on the Bamberg grid
Observed spectrum in black, model in red, offset by line. Balmer series left, helium right.

Line-profile fit — uli

profile fit on the uli grid
Observed spectrum in black, model in red, offset by line. Balmer series left, helium right.

Results and provenance

Fit — Bamberg

Teff [K]29088 ± 158
log g5.770 ± 0.026
log n(He)/n(H)-2.926 ± 0.125
reduced χ²0.995 over 638 points
radial velocity-40.0 km s−1
resolution (FWHM)2.00 Å
lines fitted12
gridsHE-0.041.fits
HE-0.125.fits
HE-0.300.fits
HE-0.550.fits
+9 more
fitted04/09/2026 19:10:47

Fit — uli

Teff [K]29715 ± 159
log g5.683 ± 0.028
log n(He)/n(H)-2.941 ± 0.095
reduced χ²0.996 over 638 points
radial velocity-40.0 km s−1
resolution (FWHM)2.00 Å
lines fitted12
gridsh667.grid
h909.grid
h97.grid
h99.grid
+1 more
fitted04/09/2026 18:37:26

Observation

telescopeSDSS 2.5-M
survey / programmeboss
date2012-06-29
exposure5405 s in 12
pipelinev5_13_2
S/N (classifier)62.6
source filespec-5948-56107-0368.fits

Gaia astrometry

Gaia DR3 source1781080159778185472
parallax [mas]0.4523 ± 0.0526
G16.233
Gabs4.548
μα [mas/yr]-5.664
μδ [mas/yr]-0.828
l, b77.848, -25.990

Published (Culpan et al. 2022)

class (Culpan)sdB
class (SIMBAD)sdB
Teff [K]30477 ± 275
log g5.64 ± 0.07
log y-4.30 ± 1.69
reference2021ApJS..256...28L

Classifier

AGREES

fitted Teff 30477 logg 5.64 logY -4.3 2021ApJS..256...28L

auto: contrast 0.08, within the 0.30 a subdwarf reaches at 27 kK, Ca II 8662/8542 = 10.0 -- the star's own Paschen lines, not a companion

Fitted lines

lineλ [Å]shift [Å]continuum at±avgfitted over
Hβ4861.32-0.65-40.0, 40.05.0-45.0, 45.0
Hγ4340.46-0.58-40.0, 36.84.5-43.0, 43.0
Hδ4101.73-0.55-40.0, 31.64.2-43.0, 43.0
Hε3970.07-0.53-28.0, 30.04.1-30.0, 35.0
Hζ3889.05-0.52-20.0, 26.24.0-31.8, 32.0
Hη3835.38-0.51-20.0, 14.64.0-20.7, 21.8
Hθ3797.90-0.51-16.0, 16.03.9-15.6, 16.7
Hι3770.63-0.50-13.0, 13.03.9-11.7, 11.6
He II 46864685.70-0.63-11.9, 11.94.9-15.0, 13.8
He I 44724471.60-0.60-15.0, 15.04.6-15.0, 15.0
He I 40264026.29-0.54-24.2, 15.04.2-15.0, 15.0
He I 49224921.93-0.66-15.0, 15.05.1-15.0, 15.0

Spectral energy distribution

Teff 29088 K · log g 5.770 · E(44−55) 0.130 · χ²r 0.19 over 37 bands

distance 2211 pc · parallax 0.4500 ± 0.0500 mas (11%) · R 0.1936 +0.0257 −0.0203 R☉ · M 0.807 +0.258 −0.180 M☉ — above the 0.47 canonical mass · L 24.2 +6.9 −4.9 L☉

Photometry against the model, with the residual beneath it in units of the error. The horizontal bar on each point is the passband, not an error; a hollow point was not fitted and the tooltip says why. Drag a box to zoom, double-click or Esc to come back out.