J/A+A/694/A175 Companions in nearby open clusters (Gratton+ 2025)
A study of the frequency and characteristics of stellar companions
and Jupiter-like planets in nearby open clusters.
Gratton R., Bonavita M., Mesa D., Desidera S., Zurlo A., Marino S.,
D'Orazi V., Rigliaco E., Nascimbeni V., Barbato D., Columba G.,
Squicciarini V.
<Astron. Astrophys. 694, A175 (2025)>
=2025A&A...694A.175G 2025A&A...694A.175G (SIMBAD/NED BibCode)
ADC_Keywords: Milky Way ; Clusters, open ; Photometry ; Optical ; Infrared ;
Radial velocities
Keywords: planets and satellites: formation -
planets and satellites: fundamental parameters - binaries: general -
open clusters and associations: general
Abstract:
Observations of companions of solar-type stars in nearby young moving
groups (NYMGs) show that they split into two groups: stellar and brown
dwarf companions (mass ratio q>0.05) and Jupiter-like (JL) planets
(q<0.02). The frequency of JL planets in NYMGs appears to be higher
than that obtained from radial velocity (RV) surveys.
We extended the search for companions to three nearby clusters of
intermediate age: Hyades, Coma Berenices, and Ursa Major. They are
older and formed in more massive events than the NYMGs.
The sample of host stars is complete for the core of the clusters,
while we considered only a fraction of the tidal tails. We used the
same methods considered for the members of NYMGs.
We obtained a fairly complete sample of stellar companions and
detected six massive JL planets. We found a lower frequency of
equal-mass companions than in the NYMGs; this might be related to how
binaries form in these environments. We also observed a concentration
of stellar binaries in the cores of Ursa Major and Coma Berenices; we
attribute this to the selective loss of low-mass systems. The observed
scarcity of wide companions in Hyades can be due to the destruction of
binaries in close encounters. The frequency of JL planets is lower
than in the NYMGs but similar to that obtained from RV surveys. This
extends the correlation with age and mass previously found for NYMGs.
Results of this study alone do not indicate whether age or mass are
the factors driving the observed correlation. A comparison of the
frequencies of free-floating planets from microlenses and in young
associations favours mass as the main driving parameter. Once the
initial cluster mass function is considered, the frequency of JL
planets in NYMGs is consistent with the results obtained using RVs.
Description:
We selected for this study the three intermediate-age stellar groups
(Hyades, Coma Berenices, and Ursa Major) that have a large population
of members within 100 pc from the Sun.
Tables giving the relevant data about companions around the program
stars. Table C1 contains the basic data. Table C2 explains if
relevant information about binarity are available and Table C3 gives
the data relevant. Table C4 gives the derived values for the stars
and their companions. Table C5 gives the references of table C4.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablec1.dat 129 374 Photometry of stars
tablec2.dat 65 353 Information about multiplicity
tablec3.dat 114 415 Binary data
tablec4.dat 172 420 Mass and separation of companion
tablec5.dat 104 41 References for tablec4
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Byte-by-byte Description of file: tablec1.dat
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Bytes Format Units Label Explanations
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1- 6 I6 --- HIP ? Hipparcos identification number
8- 13 I6 --- HD ? HD identification number
14 A1 --- m_HD Multiplicity index on HD
16- 32 A17 --- 2MASS 2MASS identifier (JHHMMSSss+DDMMSSs)
34- 49 A16 --- OName Other designations
50- 53 F4.1 --- Pmemb ? Membership probability
55- 63 F9.5 deg RAdeg ? Right Ascension (J2000)
65- 73 F9.5 deg DEdeg ? Declination (J2000)
75- 81 F7.3 mas plx ? Parallax
83- 88 F6.3 mag GmagA ? Primary Gaia G magnitude
90- 95 F6.3 mag GmagB ? Secondary Gaia G magnitude (1)
97-102 F6.3 mag KmagA ? Primary 2MASS K magnitude
104-109 F6.3 mag GMAGA ? Primary Gaia G absolute magnitude
111-116 F6.3 mag GMAGB ? Secondary Gaia G absolute magnitude (1)
118-123 F6.3 mag KMAGA ? Primary 2MASS K absolute magnitude
125-128 A4 --- Cluster Cluster
129 A1 --- Group [CLMT] Core/Tail
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Note (1): Some stars could have several values for GmagB and GMAGB,
so the lines are duplicated with only GmagB and GMAGB parameter values.
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Byte-by-byte Description of file: tablec2.dat
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Bytes Format Units Label Explanations
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1- 6 I6 --- HIP ? Hipparcos identification number
8- 13 I6 --- HD ? HD identification number
14 A1 --- m_HD Multiplicity index on HD
16- 32 A17 --- 2MASS 2MASS identifier (JHHMMSSss+DDMMSSs)
34- 52 A19 --- OName Other designations
53- 55 I3 Myr Age Age
57 I1 --- TESS [0/1] 1: TESS data; 0: No
59 I1 --- RV [0/2] 2: High precision; 1: Low precision;
0: No
61 I1 --- HCI [0/1] 1: HCI data; 0: No
63 I1 --- RUWE [0/1] 1: RUWE data; 0: No
65 I1 --- PMa [0/1] 1: PMa data; 0; No
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Byte-by-byte Description of file: tablec3.dat
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Bytes Format Units Label Explanations
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1- 6 I6 --- HIP ? Hipparcos identification number
8- 13 I6 --- HD ? HD identification number
14 A1 --- m_HD Multiplicity index on HD
16- 32 A17 --- 2MASS 2MASS identifier (JHHMMSSss+DDMMSSs)
34- 53 A20 --- OName Other designations
54- 59 F6.3 --- RUWE ? RUWE
61- 67 F7.2 km/s RV ? Radial velocity
69- 73 F5.2 km/s e_RV ? Radial velocity error
75- 77 I3 --- Nb ? Number of RV observations
79- 84 F6.2 km/s AmpRV ? Radial velocity robust amplitude
86- 91 F6.2 arcsec Sep ? Apparent separation
94- 99 F6.2 deg PA []? Position angle
101-107 F7.2 --- SNR(PMa) ? SNR PMa
109-114 F6.2 Mjup Mmin ? Minimum mass for detection using PMa
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Byte-by-byte Description of file: tablec4.dat
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Bytes Format Units Label Explanations
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1- 6 I6 --- HIP ? Hipparcos identification number
8- 13 I6 --- HD ? HD identification number
14 A1 --- m_HD Multiplicity index on HD
16- 32 A17 --- 2MASS 2MASS identifier (JHHMMSSss+DDMMSSs)
34- 51 A18 --- OName Other designations
52- 56 F5.2 Msun MassA ? Primary mass (MSun)
58- 64 F7.5 Msun MassB ? Secondary mass (MSun)
65- 74 F10.3 au a ? Semi-major axis (au)
76- 80 F5.3 --- q ? Mass ratio
82- 84 A3 --- Method Method (DYN=dynamics; VIS=Visual binary)
86-172 A87 --- Remarks Note
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Byte-by-byte Description of file: tablec5.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- Ref [1/41] Reference code
4- 22 A19 --- BibCode BibCode
24- 61 A38 --- Auth Author's name
63-104 A42 --- Com Comments
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Acknowledgements:
Raffaele Gratton, raffaele.gratton(at)inaf.it,
INAF-Osservatorio Astronomico di Padova
(End) R. Gratton [INAF-Osserv. Astron. di Padova], P. Vannier [CDS] 31-Dec-2024