J/A+A/481/661 Hyades brown dwarfs and very low mass stars (Bouvier+, 2008)
Brown dwarfs and very low mass stars in the Hyades cluster:
a dynamically evolved mass function.
Bouvier J., Kendall T., Meeus G., Testi L., Moraux E., Stauffer J.R.,
James D., Cuillandre J.-C., Irwin J., McCaughrean M.J., Baraffe I.,
Bertin E.
<Astron. Astrophys., 481, 661-672 (2008)>
=2008A&A...481..661B 2008A&A...481..661B
ADC_Keywords: Clusters, open ; Photometry ; Proper motions
Keywords: stars: luminosity function, mass function -
stars: low-mass, brown dwarfs - Galaxy:
open clusters and associations: individual: Hyades (Melotte 25)
Abstract:
We conducted a search for brown dwarfs (BDs) and very low mass (VLM)
stars in the 625Myr-old Hyades cluster in order to derive the
cluster's mass function across the stellar-substellar boundary.
We performed a deep (I=23, z=22.5) photometric survey over 16deg2
around the cluster center and followed up with K-band photometry to
measure the proper motion of candidate members and with optical and
near-IR spectroscopy of probable BD and VLM members.
Description:
Wide-field optical images were obtained in the I and z bands with the
CFHT 12 K camera. The survey was performed during several service
observing runs between September 2002 and January 2003, and consists
of 53 mosaic fields covering a total of 17.3 square degrees over the
cluster area.
Follow up K'-band imaging was obtained for 108 of the 125 optically
selected candidate members. About half of this sample was observed in
Nov/04 and the other half in Nov/05.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 98 22 Probable Hyades members based on photometry
and proper motion
tabled1.dat 94 103 Hyades probable non-members: candidate members selected
from the (I, I-z) CMD but whose infrared colors
and/or proper motion is inconsistent with membership
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See also:
J/AJ/80/379 : Hyades cluster: motion, membership and distance (Hanson+, 1975)
J/ApJ/325/798 : Einstein survey of stars in the Hyades (Micela+, 1988)
J/A+A/243/386 : Hyades members distances (Schwan 1991)
J/A+A/310/879 : Hyades binaries (Barrado+, 1996)
J/A+A/331/81 : Hyades membership (Perryman+ 1998)
J/AZh/77/96 : Abundances in Hyades red giants (Boyarchuk+, 2000)
J/A+A/367/111 : A Hipparcos study of the Hyades cluster (de Bruijne+, 2001)
J/other/NewA/8.645 : Vmag/plx relation for Hyades stars (Sharaf+, 2003)
J/AJ/127/3579 : Radial velocities of Hyades stars (Paulson+, 2004)
J/AJ/132/111 : BV(RI)Cphotometry of 77 Hyades stars (Joner+, 2006)
Byte-by-byte Description of file: table1.dat tabled1.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- --- [CFHT-Hy-]
9- 10 I2 --- CFHT ? CFHT-Hy designation (table1 only)
Cl* Melotte 25 CFHT NN in Simbad
12 A1 --- n_CFHT [1-7] Note on CFHT (1)
14- 26 A13 --- [BKM2008] Internal number
28 A1 --- n_[BKM2008] [1-7 a-c] Note on [BKM2008] (1)
31 I1 h RAh Right ascension (J2000)
33- 34 I2 min RAm Right ascension (J2000)
36- 39 F4.1 s RAs Right ascension (J2000)
41 A1 --- DE- Declination sign (J2000)
42- 43 I2 deg DEd Declination (J2000)
45- 46 I2 arcmin DEm Declination (J2000)
48- 49 I2 arcsec DEs Declination (J2000)
51- 55 F5.2 mag Imag I (822nm) magnitude
57- 60 F4.2 mag I-z I-z colour index
62- 65 F4.2 mag I-K ? I-K colour index
67- 70 I4 mas/yr pmRA ? Proper motion along RA, pmRA*cosDE
72- 75 I4 mas/yr pmDE ? Proper motion along DE
77- 98 A22 --- Oname Other name(s) (2)
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Note (1): Notes as follows:
1 = A faint companion is seen 3.2" away from this Hyades probable
member but its I-K color and proper motion indicates a
background star
2 = Classified as a non member by Reid (1993MNRAS.265..785R 1993MNRAS.265..785R).
Spectroscopically confirmed as a non-member in this study
(see text)
3 = Classified as a non member by Reid (1993MNRAS.265..785R 1993MNRAS.265..785R).
Spectroscopically confirmed as a member in this study (see text)
4 = CFHT-Hy-15 and 17 form a visual pair (RHy 240 AB)
5 = Classified as a non member by Gizis et al. (1999AJ....118..997G 1999AJ....118..997G),
see text
6 = This probable Hyades BD was also observed in the J and H bands,
yielding (J-H, H-K)=(0.51, 0.43)
7 = This probable Hyades BD was also observed in the J and H bands,
yielding (J-H, H-K)=(1.12, 0.77)
a = This candidate has a proper motion consistent with membership but
is too blue in I-K to be a cluster member
b = This candidate has candidate has no follow up K-band photometry
c = This extremely red object was also observed in the J and H bands,
yielding (J-H, H-K)=(2.24, 0.91)
Note (2): Other names are from:
VA = van Altena (1969AJ.....74....2V 1969AJ.....74....2V), Cl* Melotte 25 VA NNN in Simbad
LP = Luyten et al. (1981, Cat. I/98)
HAN = Hanson (1975AJ.....80..379H 1975AJ.....80..379H), Cl* Melotte 25 Han NNN in Simbad
RHy = Reid (1992MNRAS.257..257R 1992MNRAS.257..257R), Cl* Melotte 25 REID NNN in Simbad
LH = Leggett & Hawkins (1988MNRAS.234.1065L 1988MNRAS.234.1065L),
Cl* Melotte 25 LH NNN in Simbad
LHD = Leggett et al. (1994AJ....108..944L 1994AJ....108..944L)
2MASS = Gizis et al. (1999AJ....118..997G 1999AJ....118..997G)
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 30-Jun-2008