J/A+A/395/813 Alpha Per faint stars photometry (Barrado y Navascues+, 2002)
A substellar mass function for Alpha Persei.
Barrado y Navascues D., Bouvier J., Stauffer J.R., Lodieu N.,
McCaughrean M.J.
<Astron. Astrophys. 395, 813 (2002)>
=2002A&A...395..813B 2002A&A...395..813B
ADC_Keywords: Clusters, open ; Stars, faint ; Photometry, infrared ;
Photometry, Cousins
Keywords: open clusters and associations: individual: Alpha Per -
stars: low-mass, brown dwarfs - stars: luminosity, mass functions
Abstract:
We present a deep, wide-field optical survey of the young stellar
cluster Alpha Per, in which we have discovered a large population of
candidate brown dwarfs. Subsequent infrared photometric follow-up
shows that the majority of them are probable or possible members of
the cluster, reaching to a minimum mass of 0.035M☉.
Description:
We obtained deep optical imaging of the Alpha Per open cluster using
the KPNO 4-m CCD mosaic camera, MOSA, on November 19-22 1998. All of
the images were obtained with the facility R and I filters.
In addition to the KPNO/MOSA observations, we undertook several
infrared observing campaigns at the Hispano-German Calar Alto
Observatory in order to obtain additional data for candidate cluster
members. These runs included November 22-23 1999, using Omega-Cass on
the 3.5-m telescope; February 16-21 2001 and November 6-7 2001, using
MAGIC on the 2.2-m telescope; and December 11-14 2000 and December
28-31 2001 using Omega-Prime on the 3.5-m telescope. We observed a
total of 53 Alpha Per candidates in the magnitude range
K'=13.0-19.2mag, equivalent to Ic=15.7-21.7mag. All were observed in
the K' filter, while 24 were also measured at J, and a handful also at
H.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 142 101 Alpha Per data from KPNO/MOSA 1998. Probable
members, possible members,
probable non-members, and no IR data.
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See also:
B/2mass : The 2MASS database (IPAC/UMass, 2000)
V/80 : Low-Mass Stars' Membership in Alpha Per Cluster (Prosser, 1992)
J/AN/319/201 : Alpha Per cluster low-mass members. I. (Prosser+, 1998)
J/AN/319/215 : Alpha Per cluster low-mass members. II. (Prosser+, 1998)
Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 2 A2 --- --- [AP]
3- 5 I3 --- AP AP designation (APNNN),
Cl* Melotte 20 AP NNN in Simbad
7 I1 h RAh Right ascension (J2000.0)
9- 10 I2 min RAm Right ascension (J2000.0)
12- 16 F5.2 s RAs Right ascension (J2000.0)
18 A1 --- DE- Declination sign (J2000.0)
19- 20 I2 deg DEd Declination (J2000.0)
22- 23 I2 arcmin DEm Declination (J2000.0)
25- 28 F4.1 arcsec DEs Declination (J2000.0)
30- 35 F6.3 mag Ic KPNO/MOSA Cousins I magnitude
37- 41 F5.3 mag Rc-Ic KPNO/MOSA Cousins Rc-Ic colour index
43- 47 F5.3 mag e_Ic rms uncertainty on Ic
49- 53 F5.3 mag e_Rc-Ic rms uncertainty on Rc-Ic
55 A1 --- l_Jmag Limit flag on Jmag
56- 61 F6.3 mag Jmag ? 2MASS J magnitude
63- 67 F5.3 mag e_Jmag ? rms uncertainty on Jmag
69 A1 --- l_Hmag Limit flag on Hmag
70- 75 F6.3 mag Hmag ? 2MASS H magnitude
77- 81 F5.3 mag e_Hmag ? rms uncertainty on Hmag
83 A1 --- l_Ksmag Limit flag on Ksmag
84- 89 F6.3 mag Ksmag ? 2MASS Ks magnitude
91- 95 F5.3 mag e_Ksmag ? rms uncertainty on Ksmag
97 A1 --- l_Jmag2 Limit flag on Jmag2
98-103 F6.3 mag Jmag2 ? CAHA J magnitude
105-109 F5.3 mag e_Jmag2 ? rms uncertainty on Jmag2
111 A1 --- l_K'mag Limit flag on K'mag
112-117 F6.3 mag K'mag ? CAHA K' magnitude
119-123 F5.3 mag e_K'mag ? rms uncertainty on K'mag
125-130 F6.3 mag Hmag2 ? CAHA H magnitude
132-136 F5.3 mag e_Hmag2 ? rms uncertainty on Hmag2
138 A1 --- Source Observation date code (1)
140-141 A2 --- Member [Y? N] Membership
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Note (1): Observation dates:
a = 1999 November
b = 2000 February
c = 2000 December
d = 2001 November
e = 2001 December
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History:
From electronic version of the journal
(End) James Marcout, Patricia Bauer [CDS] 20-Jan-2003