J/A+A/710/A285 NGC 2509 spellar param. and abundances (Boeche+, 2026)
The open cluster NGC 2509: Stellar rotation and main sequence turnoff extension
from FLAMES spectroscopy.
Boeche C., Alonso-Santiago J., Bragaglia A., Frasca A., Vallenari A.,
Kallimanis I.N., Carrera R., Bossini D., Lucatello S., D'Orazi V., Costa G.
<Astron. Astrophys. 710, A285 (2026)>
=2026A&A...710A.285B 2026A&A...710A.285B (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, open ; Abundances ; Radial velocities ;
Effective temperatures ; Optical
Keywords: stars: abundances - stars: evolution - stars: fundamental parameters -
Galaxy: disk - open clusters and associations: general -
open clusters and associations: individual: NGC 2509
Abstract:
NGC 2509 is a distant (∼2.5kpc) and little-studied open cluster
located in the third Galactic quadrant. It is a moderately old
cluster, whose age has not yet been precisely determined. The
main-sequence stars in NGC 2509 follow a narrow distribution in the
color-magnitude diagram, unlike other clusters of similar age. In
addition, its chemical composition has never been investigated. To
address these issues and characterize the cluster we performed
moderate- and high-resolution spectroscopy with FLAMES@VLT of 132
stars, both dwarfs and giants, which represents a significant fraction
(∼73%) of likely members. We provide atmospheric stellar parameters
and, for the first time, chemical abundances for 21 species with
atomic numbers up to 60. In our analysis we followed two different
methodologies, both of which will be used for the incoming WEAVE
stellar surveys. We find an average radial velocity for NGC 2509 of
58.6±1.3km/s and a mild supersolar metallicity ([Fe/H]∼0.1dex). This
value is slightly higher than expected according to its galactocentric
distance, but still compatible with the Galactic gradient. From the
lithium content of the dwarfs and the isochrone-fitting method we
obtain an age for NGC 2509 of 1.26±0.3Gyr. The reddening across the
cluster field is negligible (AV=0.25±0.02mag). The cluster
peculiar main sequence turnoff is due to a narrow distribution of the
rotational velocities peaking at vsini∼80km/s, with little dispersion.
The chemical pattern of NGC 2509 follows the Galactic trends shown by
other open clusters in the Galactic thin disk.
Description:
Stellar parameters, radial velocities, Vsini, chemical abundances from
UVES and GIRAFFE spectra.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablec1.dat 131 132 Targets, observing modes, radial velocity,
vsini, and AP (measured by ROTFIT)
tablec2.dat 542 61 Stellar parameters and chemical abundances
derived with SP_Ace
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See also:
I/355 : Gaia DR3 Part 1. Main source (Gaia Collaboration, 2022)
Byte-by-byte Description of file: tablec1.dat
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Bytes Format Units Label Explanations
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1- 19 I19 --- GaiaDR3 Gaia DR3 source ID
21- 25 A5 --- 1of3 Observed/wavelength window in the
1st observing run
27- 30 A4 --- 2of3 Observed/wavelength window in the
2nd observing run
32- 35 A4 --- 3of3 Observed/wavelength window in the
3rd observing run
37- 45 F9.6 mag Gmag Gaia DR3 G mean magnitude
47- 54 F8.6 mag BP-RP Gaia DR3 GBP-GRP color
56- 59 I4 K Teff ? Effective temperature
61- 63 I3 K e_Teff ? Teff error
65- 69 F5.2 [cm/s2] logg ? log surface gravity
71- 75 F5.2 [cm/s2] e_logg ? logg error
77- 81 F5.2 [Sun] [Fe/H] ? Iron abundance relative to the Sun
83- 87 F5.2 [Sun] e_[Fe/H] ? [Fe/H] error
89- 94 F6.1 km/s vsini ? Projected rotational velocity
96- 99 F4.1 km/s e_vsini ? vsini error
101-106 F6.2 km/s RV ? Average heliocentric radial velocity
108-112 F5.2 km/s e_RV ? RV error
114-120 A7 --- SpType Spectral Type
122-126 A5 --- HRused GIRAFFE HR interval observed
128-131 A4 --- Remarks Binarity
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Byte-by-byte Description of file: tablec2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 19 I19 --- GaiaDR3 Gaia DR3 source ID
21 I1 --- conv [0] SP_Ace convergence (1)
23- 26 F4.2 km/s RVb [0.3/3.9] Radial velocity correction in
the blue window
28- 33 F6.2 km/s RVr [-21.7/2.4] Radial velocity correction in
the red window
35- 38 F4.2 0.1nm FWHMb [0.16/0.57] Full Width Half Maximum adopted in
the blue window
40- 43 F4.2 0.1nm FWHMr [0.18/3.07] Full Width Half Maximum adopted in
the red window
45- 49 F5.2 --- SNR [19.1/88.6] Signal-to-Noise Ratio
51- 54 F4.2 --- chisq [0.35/1.69] Chi squared from model fitting
56- 59 I4 K Teff [4514/6458] effective temperature
61- 64 I4 K b_Teff [4481/6423] Teff lower limit
66- 69 I4 K B_Teff [4523/6476]? Teff upper limit
71- 74 F4.2 [cm/s2] logg [2.56/4.87] log surface gravity
76- 79 F4.2 [cm/s2] b_logg [2.48/4.82] logg lower limit
81- 85 F5.2 [cm/s2] B_logg [2.62/5.12]? logg upper limit
87- 90 F4.2 [-] [M/H] [0.01/0.38] Metallicity
92- 96 F5.2 [-] b_[M/H] [-0.04/0.36] [M/H] lower limit
98-102 F5.2 [-] B_[M/H] [0.03/0.37]? [M/H] upper limit
104-107 F4.2 [-] [Fe/H] [0.03/0.44] Iron abundance [Fe/H]
109-113 F5.2 [-] b_[Fe/H] [-0.05/0.42] [Fe/H] lower limit
115-118 F4.2 [-] B_[Fe/H] [0.04/0.47] [Fe/H] upper limit
120-123 I4 --- o_[Fe/H] [233/1355] Number of Fe lines measured
125-129 F5.2 [-] [Na/H] [-0.06/0.96]? Natrium abundance [Na/H]
131-135 F5.2 [-] b_[Na/H] [-0.08/0.79]? [Na/H] lower limit
137-141 F5.2 [-] B_[Na/H] [0.13/1.16]? [Na/H] upper limit
143 I1 --- o_[Na/H] [0/8] Number of Na lines measured
145-149 F5.2 [-] [Mg/H] [-0.27/0.58]? Magnesium abundance [Mg/H]
151-155 F5.2 [-] b_[Mg/H] [-0.27/0.49]? [Mg/H] lower limit
157-161 F5.2 [-] B_[Mg/H] [-0.12/0.66]? [Mg/H] upper limit
163 I1 --- o_[Mg/H] [2/8] Number of Mg lines measured
165-169 F5.2 [-] [Al/H] [-0.00/0.47]? Aluminum abundance [Al/H]
171-175 F5.2 [-] b_[Al/H] [-0.13/0.41]? [Al/H] lower limit
177-181 F5.2 [-] B_[Al/H] [0.1/0.54]? [Al/H] upper limit
183-184 I2 --- o_[Al/H] [3/10] Number of Al lines measured
186-189 F4.2 [-] [Si/H] [0.03/0.37] Silicon abundance [Si/H]
191-194 F4.2 [-] b_[Si/H] [0.01/0.33] [Si/H] lower limit
196-199 F4.2 [-] B_[Si/H] [0.05/0.4] [Si/H] upper limit
201-203 I3 --- o_[Si/H] [40/126] Number of Si lines measured
205-209 F5.2 [-] [Ca/H] [-0.15/0.52] Calcium abundance [Ca/H]
211-215 F5.2 [-] b_[Ca/H] [-0.29/0.47]? [Ca/H] lower limit
217-221 F5.2 [-] B_[Ca/H] [-0.1/0.58] [Ca/H] upper limit
223-224 I2 --- o_[Ca/H] [15/54] Number of Ca lines measured
226-230 F5.2 [-] [Sc/H] [-0.31/0.32]? Scandium abundance [Sc/H]
232-236 F5.2 [-] b_[Sc/H] [-0.29/0.23]? [Sc/H] lower limit
238-242 F5.2 [-] B_[Sc/H] [-0.18/0.45]? [Sc/H] upper limit
244-245 I2 --- o_[Sc/H] [1/77] Number of Sc lines measured
247-250 F4.2 [-] [Ti/H] [0.08/0.57] Titanium abundance [Ti/H]
252-256 F5.2 [-] b_[Ti/H] [-0.11/0.49] [Ti/H] lower limit
258-261 F4.2 [-] B_[Ti/H] [0.11/0.66] [Ti/H] upper limit
263-265 I3 --- o_[Ti/H] [22/405] Number of Ti lines measured
267-271 F5.2 [-] [V/H] [-0.08/0.46] Vanadium abundance [V/H]
273-277 F5.2 [-] b_[V/H] [-0.25/0.39]? [V/H] lower limit
279-282 F4.2 [-] B_[V/H] [0.02/0.54] [V/H] upper limit
284-286 I3 --- o_[V/H] [9/187] Number of V lines measured
288-291 F4.2 [-] [Cr/H] [0.02/0.54] Chromium abundance [Cr/H]
293-297 F5.2 [-] b_[Cr/H] [-0.03/0.45] [Cr/H] lower limit
299-302 F4.2 [-] B_[Cr/H] [0.04/0.66] [Cr/H] upper limit
304-306 I3 --- o_[Cr/H] [11/272] Number of Cr lines measured
308-312 F5.2 [-] [Mn/H] [-0.35/0.38]? Manganese abundance [Mn/H]
314-318 F5.2 [-] b_[Mn/H] [-0.34/0.22]? [Mn/H] lower limit
320-324 F5.2 [-] B_[Mn/H] [-0.23/0.6]? [Mn/H] upper limit
326-328 I3 --- o_[Mn/H] [6/113] Number of Mn lines measured
330-333 F4.2 [-] [Co/H] [0.03/0.44] Cobalt abundance [Co/H]
335-339 F5.2 [-] b_[Co/H] [-0.06/0.36] [Co/H] lower limit
341-344 F4.2 [-] B_[Co/H] [0.1/0.51] [Co/H] upper limit
346-348 I3 --- o_[Co/H] [14/217] Number of Co lines measured
350-354 F5.2 [-] [Ni/H] [-0.05/0.47] Nickel abundance [Ni/H]
356-360 F5.2 [-] b_[Ni/H] [-0.21/0.42] [Ni/H] lower limit
362-365 F4.2 [-] B_[Ni/H] [0.04/0.52] [Ni/H] upper limit
367-369 I3 --- o_[Ni/H] [40/233] Number of Ni lines measured
371-375 F5.2 [-] [Cu/H] [-0.24/0.57]? Copper abundance [Cu/H]
377-381 F5.2 [-] b_[Cu/H] [-0.27/0.31]? [Cu/H] lower limit
383-387 F5.2 [-] B_[Cu/H] [-0.01/0.86]? [Cu/H] upper limit
389 I1 --- o_[Cu/H] Number of Cu lines measured
391-395 F5.2 [-] [Zn/H] [-0.12/0.24]? Zinc abundance [Zn/H]
397-401 F5.2 [-] b_[Zn/H] [-0.28/0.00]? [Zn/H] lower limit
403-407 F5.2 [-] B_[Zn/H] [0.13/0.4]? [Zn/H] upper limit
409 I1 --- o_[Zn/H] Number of Zn lines measured
411-415 F5.2 [-] [Y/H] [-0.21/0.53]? Yttrium abundance [Y/H]
417-421 F5.2 [-] b_[Y/H] [-0.15/0.35]? [Y/H] lower limit
423-427 F5.2 [-] B_[Y/H] [-0.02/0.96]? [Y/H] upper limit
429-430 I2 --- o_[Y/H] [1/32] Number of Y_ lines measured
432-436 F5.2 [-] [Zr/H] [0.13/0.71]? Zirconium abundance [Zr/H]
438-442 F5.2 [-] b_[Zr/H] [-0.01/0.3]? [Zr/H] lower limit
444-448 F5.2 [-] B_[Zr/H] [0.22/0.57]? [Zr/H] upper limit
450-451 I2 --- o_[Zr/H] Number of Zr lines measured
453-457 F5.2 [-] [Ba/H] [-0.36/0.71]? Barium abundance [Ba/H]
459-463 F5.2 [-] b_[Ba/H] [-0.32/0.32]? [Ba/H] lower limit
465-469 F5.2 [-] B_[Ba/H] [-0.05/0.91]? [Ba/H] upper limit
471 I1 --- o_[Ba/H] [2/6] Number of Ba lines measured
473-477 F5.2 [-] [La/H] [-0.15/0.63]? Lanthanum abundance [La/H]
479-483 F5.2 [-] b_[La/H] [0.01/0.48]? [La/H] lower limit
485-489 F5.2 [-] B_[La/H] [0.33/0.91]? [La/H] upper limit
491-492 I2 --- o_[La/H] Number of La lines measured
494-498 F5.2 [-] [Ce/H] [-0.18/0.48]? Cerium abundance [Ce/H]
500-504 F5.2 [-] b_[Ce/H] [-0.23/0.04]? [Ce/H] lower limit
506-510 F5.2 [-] B_[Ce/H] [-0.03/0.71]? [Ce/H] upper limit
512-513 I2 --- o_[Ce/H] Number of Ce lines measured
515-519 F5.2 [-] [Nd/H] [-0.23/0.8]? Neodymium abundance [Nd/H]
521-525 F5.2 [-] b_[Nd/H] [-0.12/0.38]? [Nd/H] lower limit
527-531 F5.2 [-] B_[Nd/H] [0.15/0.91]? [Nd/H] upper limit
533-534 I2 --- o_[Nd/H] Number of Nd lines measured
536-542 A7 --- Mode [giraffe uves] Spectrograph used
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Note (1): if conv=0: SP_Ace converged; if conv!=0: SP_Ace did not converge.
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Acknowledgements:
Corrado Boeche, corrado.boeche(at)inaf.it
License: CC-BY-4.0
(End) Patricia Vannier [CDS] 04-Jun-2026