J18104+4154sdB

SDSSJ181027.90+415413.9  ·  18:10:27.91 41:54:13.68  ·  Culpan knownhsd

χ²/N = 0.98

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.

Results and provenance

Fit — Bamberg

Teff [K]26302 ± 314
log g5.442 ± 0.052
log n(He)/n(H)-2.973 ± 0.099
reduced χ²0.982 over 637 points
radial velocity-11.0 km s−1
resolution (FWHM)2.50 Å
lines fitted12
gridsHE-0.041.fits
HE-0.125.fits
HE-0.300.fits
HE-0.550.fits
+9 more
fitted04/09/2026 18:32:50

Fit — Lei (TLUSTY)

Teff [K]27760 ± 190
log g5.370 ± 0.030
log n(He)/n(H)-2.860 ± 0.060
gridsLei et al. 2019, ApJ 881, 135
SYNSPEC 49 spectra from NLTE TLUSTY 204 model atmospheres, through XTgrid

Observation

S/N (classifier)25.3
source filespec-56785-HD180759N395524B01_sp11-121.fits.gz

Gaia astrometry

Gaia DR3 source2113506200378734848
parallax [mas]0.4920 ± 0.0359
G16.127
Gabs4.578
μα [mas/yr]-1.935
μδ [mas/yr]-6.049
l, b69.031, 24.982

Published (Culpan et al. 2022)

class (Culpan)sdB
class (SIMBAD)sd
Teff [K]27231 ± 371
log g5.32 ± 0.05
log y-3.03 ± 0.07
reference2021ApJS..256...28L

Classifier

AGREES

fitted Teff 27231 logg 5.32 logY -3.03 2021ApJS..256...28L

auto: contrast 0.16, within the 0.31 a subdwarf reaches at 27 kK, Mg I b suggests a companion but Ca II does not (0.1 sigma)

Fitted lines

lineλ [Å]shift [Å]continuum at±avgfitted over
Hβ4861.32-0.18-40.0, 40.05.0-45.0, 45.0
Hγ4340.46-0.16-40.0, 36.84.5-43.0, 43.0
Hδ4101.73-0.15-40.0, 31.64.2-43.0, 43.0
Hε3970.07-0.15-28.0, 30.04.1-30.0, 35.0
Hζ3889.05-0.14-20.0, 26.24.0-31.8, 32.0
Hη3835.38-0.14-20.0, 14.64.0-20.7, 21.8
Hθ3797.90-0.14-16.0, 16.03.9-15.6, 16.7
Hι3770.63-0.14-13.0, 13.03.9-11.7, 11.6
He II 46864685.70-0.17-11.9, 11.94.9-15.0, 13.8
He I 44724471.60-0.16-15.0, 15.04.6-15.0, 15.0
He I 40264026.29-0.15-24.2, 15.04.2-15.0, 15.0
He I 49224921.93-0.18-15.0, 15.05.1-15.0, 15.0