J/A+A/699/A142 Blue stragglers in Galactic clusters (Carrasco-Varela+, 2025)
Beyond the main sequence: Binary evolution pathways to blue stragglers in the
Gaia era I. Galactic open and globular clusters.
Carrasco-Varela F.F., Nayak P.K., Puzia T.H.
<Astron. Astrophys. 699, A142 (2025)>
=2025A&A...699A.142C 2025A&A...699A.142C (SIMBAD/NED BibCode)
ADC_Keywords: Milky Way ; Associations, stellar ; Stars, double and multiple ;
Effective temperatures ; Stars, masses ; Stars, ages
Keywords: blue stragglers - stars: fundamental parameters -
globular clusters: general - open clusters and associations: general
Abstract:
The study of blue straggler stars (BSS) provides insights into the
mechanisms of stellar mass exchange during binary stellar evolution
and the complex gravitational interactions within dense stellar
systems. In combination, they enhance our understanding of possible
lifecycles of stars and the evolutionary pathways of star clusters.
We study the populations of BSSs in 41 globular clusters (GCs) and 42
open clusters (OCs) adopting photometry, proper motion and parallax
from the Gaia Data Release 3 (DR3), confirming their cluster
membership. We find a total of 4399 BSSs: all GCs show the presence of
BSSs (3965 or ∼90% of the sample), whereas only 42 out of 129 studied
OCs show the presence of BSSs (434 or ∼10% of the sample). Clusters
younger than ∼500Myr do not host any BSSs.
We derive their astrophysical parameters such as effective
temperature, surface gravity and mass based on color-temperature
relations, isochrone models and Gaia DR3 spectroscopy (if available).
We find values for Teff=6800±585K and 7570±1400K; and an average
mass of <MBSS≥1.02±0.1M☉ and <MBSS≥1.75±0.45M☉
for GCs and OCs, respectively. We finally compute the difference of
the BSS mass and the main sequence turn-off (MSTO) mass of its
respective cluster, normalized by the MSTO mass, for every identified
BSS.
Based on this parameter and BSSs ages derived from isochrone models we
find: i) GC BSSs that are most likely to be formed through collisions
show a "boost" for ages ∼1-2Gyr, in agreement with ages for
core-collapse events in GCs reported in previous studies; ii) a double
sequence for GC BSSs that could indicate the hint of a pre/post-merger
or close-binary scenario.
Description:
We tabulated the coordinates and parameters of BSS, RSS and YSS
detected in Galactic open and globular clusters using Gaia DR3 data.
We also tabulated the list of clusters with the stellar parameters.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tabled1.dat 113 83 Parameters of star cluster
tabled2.dat 207 4399 Parameters of blue straggler stars (BSSs)
detected in this study
rss.dat 182 1476 Parameters of red straggler stars (RSSs)
detected in this study
yss.dat 182 1401 Parameters of yellow straggler stars (YSSs)
detected in this study
plots_OCs/* . 42 Open clusters upper-lower sequence plots in png
plots_GCs/* . 41 Galactic clusters upper-lower sequence plots
in png
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See also:
I/355 : Gaia DR3 Part 1. Main source (Gaia Collaboration, 2022)
Byte-by-byte Description of file: tabled1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 12 A12 --- Cluster Cluster name
14- 29 A16 --- Type Cluster type (open or globular)
31- 37 F7.3 deg RAdeg Gaia DR3 Right Ascension (ICRS) at Ep=2016.0
39- 45 F7.3 deg DEdeg Gaia DR3 Declination (ICRS) at Ep=2016.0
47- 52 F6.3 [yr] logAge Decimal logarithm of the age
54- 58 F5.3 [yr] e_logAge Error in decimal logarithm of the age
60- 64 F5.3 mag Av Extinction
66- 70 I5 pc Dist Distance to the cluster
72- 77 F6.3 [-] [Fe/H] Metallicity of the cluster
79- 82 I4 [K] Teff-IRFM MSTO Teff from IRFM models
84- 86 I3 [K] e_Teff-IRFM Error in MSTO Teff from IRFM models
88- 91 I4 [K] Teff-iso MSTO Teff from isochrone models
93- 95 I3 --- NBSS Number of identified BSSs
97-101 I5 --- NMS ?=- Number of identified MS stars 1mag fainter
than MSTO
103-107 F5.3 --- fBSS/MS ?=- Fraction between number of BSS and number
of MS stars
109-113 F5.3 --- e_fBSS/MS ?=- Error in fraction between BSS and MS stars
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Byte-by-byte Description of file: tabled2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 12 A12 --- Cluster Cluster name to which star belongs
14- 29 A16 --- Type Type of cluster (open or globular)
31- 49 I19 --- GaiaDR3 Gaia DR3 Source ID
51- 59 F9.5 deg RAdeg Gaia DR3 Right Ascension (ICRS)
at Ep=2016.0
61- 69 F9.5 deg DEdeg Gaia DR3 Declination (ICRS) at Ep=2016.0
71- 77 F7.3 mas/yr pmRA Gaia DR3 Proper Motion along RA, pmRA*cosDE
79- 85 F7.3 mas/yr pmDE Gaia DR3 Proper motion along DE
87- 92 F6.3 mas plx Gaia DR3 Parallax
94- 98 I5 K Teff-IRFM Effective temperature from IRFM models
100-103 I4 K e_Teff-IRFM Error in effective temperature
from IRFM models
105-109 I5 K Teff-iso Effective temperature from isochrone
fittings
111-113 I3 K e_Teff-iso Error in effective temperature
from isochrone fittings
115-120 F6.3 [yr] logAge-iso Decimal logarithm of the age
from isochrone fittings
122-126 F5.3 [yr] e_logAge-iso Error in decimal logarithm of the age
from isochrone fittings
128-131 F4.2 Msun Mass-iso Stellar mass from isochrone fittings
133-136 F4.2 Msun e_Mass-iso Error in stellar mass from isochrone
fittings
138-141 F4.2 Lsun logL-iso Decimal logarithm of the luminosity
from isochrone fittings
143-147 F5.3 Lsun e_logL-iso Error in decimal logarithm of the
luminosity from isochrone fittings
149-153 F5.3 [cm/s2] logg-iso Decimal logarithm of the surface gravity
from isochrone fittings
155-159 F5.3 [cm/s2] e_logg-iso Error in decimal logarithm of the surface
gravity from isochrone fittings
161-165 I5 K Teff-xpp ?=- Effective temperature from XPP models
167-170 I4 K e_Teff-xpp ?=- Error in effective temperature
from XPP models
172-176 F5.3 [cm/s2] logg-xpp ?=- Decimal logarithm of the surface
gravity from XPP models
178-182 F5.3 [cm/s2] e_logg-xpp ?=- Error in decimal logarithm of the
surface gravity from XPP models
184-187 F4.2 --- Me Fractional mass excess
189-193 A5 --- MeSeq BSS sequence classification
195-200 F6.3 mag BPMAG Absolute GBP magnitude
202-207 F6.3 mag (BP-RP)0 De-reddened (BP-RP) color
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Byte-by-byte Description of file: rss.dat yss.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 12 A12 --- Cluster Cluster name to which star belongs
14- 29 A16 --- Type Type of cluster to which star belongs
31- 49 I19 --- GaiaDR3 Gaia DR3 Source ID
51- 59 F9.5 deg RAdeg Gaia DR3 Right Ascension (ICRS)
at Ep=2016.0
61- 69 F9.5 deg DEdeg Gaia DR3 Declination (ICRS) at Ep=2016.0
71- 77 F7.3 mas/yr pmRA Gaia DR3 Proper Motion along RA, pmRA*cosDE
79- 85 F7.3 mas/yr pmDE Gaia DR3 Proper motion along DE
87- 92 F6.3 mas plx Gaia DR3 Parallax
94- 97 I4 K Teff-IRFM Effective temperature from IRFM models
99-101 I3 K e_Teff-IRFM Error in effective temperature
from IRFM models
103-106 I4 K Teff-iso Effective temperature from isochrone
fittings
108-110 I3 K e_Teff-iso Error in effective temperature
from isochrone fittings
112-117 F6.3 [yr] logAge-iso Decimal logarithm of the age
from isochrone fittings
119-123 F5.3 [yr] e_logAge-iso Error in decimal logarithm of the age
from isochrone fittings
125-128 F4.2 Msun Mass-iso Stellar mass from isochrone fittings
130-133 F4.2 Msun e_Mass-iso Error in stellar mass from isochrone
fittings
135-138 F4.2 Lsun logL-iso Decimal logarithm of the luminosity
from isochrone fittings
140-144 F5.3 Lsun e_logL-iso Error in decimal logarithm of the
luminosity from isochrone fittings
146-150 F5.3 [cm/s2] logg-iso Decimal logarithm of the surface
gravity from isochrone fittings
152-156 F5.3 [cm/s2] e_logg-iso Error in decimal logarithm of the surface
gravity from isochrone fittings
158-161 I4 K Teff-xpp ?=- Effective temperature from XPP models
163-165 I3 K e_Teff-xpp ?=- Error in effective temperature
from XPP models
167-171 F5.3 [cm/s2] logg-xpp ?=- Decimal logarithm of the surface
gravity from XPP models
173-177 F5.3 [cm/s2] e_logg-xpp ?=- Error in decimal logarithm of the
surface gravity from XPP models
179-182 F4.2 --- Me Fractional mass excess
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Acknowledgements:
Prasanta Kumar Nayak, nayakphy(at)gmail.com
(End) Patricia Vannier [CDS] 14-May-2025