J/ApJ/697/1578 A debris disk study of Praesepe (Gaspar+, 2009)
The low level of debris disk activity at the time of the late heavy bombardment:
a Spitzer study of Praesepe.
Gaspar A., Rieke G.H., Su K.Y.L., Balog Z., Trilling D., Muzzerole J.,
Apai D., Kelly B.C.
<Astrophys. J., 697, 1578-1596 (2009)>
=2009ApJ...697.1578G 2009ApJ...697.1578G
ADC_Keywords: Clusters, open ; Photometry, infrared ; Stars, dwarfs
Keywords: circumstellar matter - infrared: stars - open clusters and
associations: individual (Praesepe, M44, NGC 2632, Beehive) -
planetary systems: formation - stars: evolution
Abstract:
We present 24um photometry of the intermediate-age open cluster
Praesepe. We assemble a catalog of 193 probable cluster members that
are detected in optical databases, the Two Micron All Sky Survey
(2MASS), and at 24um, within an area of ∼2.47deg2. Mid-IR excesses
indicating debris disks are found for one early-type and for three
solar-type stars. Corrections for sampling statistics yield a 24um
excess fraction (debris disk fraction) of 6.5%±4.1% for luminous and
1.9%±1.2% for solar-type stars. The incidence of excesses is in
agreement with the decay trend of debris disks as a function of age
observed for other cluster and field stars.
Description:
We used MIPS to observe Praesepe as part of the GTO program PID 30429
(2007 May 30). The center part of the cluster (8h40m21s, 19°38'40")
was imaged using three scan maps.
Out of the 193 cluster members that we detected at all wavelengths in
the combined catalog (SDSS, WEBDA and 2MASS), 29 were early (B5-A9)
and 164 later (F0-M0) spectral types.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 111 193 Photometry of Praesepe members in the 24µm band
--------------------------------------------------------------------------------
See also:
II/294 : The SDSS Photometric Catalog, Release 7 (Adelman-McCarthy+, 2009)
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
I/257 : Proper Motions in Praesepe (Wang+, 1995)
J/A+A/510/A27 : Very low mass stars in Praesepe (Boudreault+, 2010)
J/AJ/134/2340 : Membership of Praesepe and Coma Berenices clusters (Kraus+,
2007)
J/AJ/124/1570 : JHKs photometry in Praesepe (Adams+, 2002)
J/A+A/375/989 : JHK photometry of Praesepe low-mass stars (Bouvier+, 2001)
J/A+AS/109/29 : Very low mass stars in Praesepe (Hambly+, 1995)
http://www.univie.ac.at/webda/navigation.html : WEBDA database access
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- Seq Identification number
5 I1 h RAh Hour of right ascension (J2000)
7- 8 I2 min RAm Minute of right ascension (J2000)
10- 14 F5.2 s RAs Second of right ascension (J2000)
16 A1 --- DE- Sign of declination (J2000)
17- 18 I2 deg DEd Degree of declination (J2000)
20- 21 I2 arcmin DEm Arcminute of declination (J2000)
23- 27 F5.2 arcsec DEs Arcsecond of declination (J2000)
29- 33 F5.2 mag gmag SDSS g-band magnitude
34 A1 --- f_gmag [*] magnitude calculated from B (1)
36- 40 F5.2 mag rmag SDSS r-band magnitude
41 A1 --- f_rmag [*] magnitude calculated from V (1)
43- 47 F5.2 mag Ksmag 2MASS Ks-band magnitude
49- 53 F5.2 mag e_Ksmag Ksmag uncertainty
55- 59 F5.2 mag [24] Spitzer/MIPS 24um band magnitude (2)
61- 64 F4.2 mag e_[24] 24um-band magnitude uncertainty
66- 71 F6.2 mJy F24 Spitzer/MIPS 24um flux (2)
73- 76 F4.2 mJy e_F24 F24 uncertainty
78- 82 F5.1 mas/yr pmRA ? Proper motion in right ascension
83 A1 --- --- [0]
85- 89 F5.1 mas/yr pmDE ? Proper motion in declination
90 A1 --- --- [0]
92- 94 I3 --- WJJP ? Number from Wang et al. 1995, Cat. I/257
(<Cl* NGC 2632 WJJP NNN> in Simbad)
96-111 A16 --- 2MASS 2MASS identification (HHMMSSss+DDMMSSs)
--------------------------------------------------------------------------------
Note (1): The r and/or g magnitudes marked with a star were calculated from
B and V WEBDA magnitudes as described in Section 3, while the rest are
the original SDSS values.
Note (2): The [24] magnitudes are the ones that were calibrated to the
2MASS Ks magnitudes, while the mJy values in the F24 column are the
original flux values.
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Emmanuelle Perret [CDS] 31-May-2011