J/ApJ/672/558 MIPS observations of h and χ Persei (Currie+, 2008)
The rise and fall of debris disks: MIPS observations of h and χ Persei and
the evolution of Mid-IR emission from planet formation.
Currie T., Kenyon S.J., Balog Z., Rieke G., Bragg A., Bromley B.
<Astrophys. J., 672, 558-574 (2008)>
=2008ApJ...672..558C 2008ApJ...672..558C
ADC_Keywords: Clusters, open ; Photometry, millimetric/submm ;
Photometry, infrared
Keywords: circumstellar matter - infrared: stars -
open clusters and associations: individual (NGC 869, NGC 884) -
planetary systems: formation - planetary systems: protoplanetary disks
Abstract:
We describe Spitzer MIPS observations of the double cluster, h and
χ Persei, covering a ∼0.6deg2 area surrounding the cores of
both clusters. The data are combined with IRAC and 2MASS data to
investigate ∼616 sources from 1.25-24um. We use the long-baseline
Ks-[24] color to identify two populations with IR excess indicative of
circumstellar material: Be stars with 24um excess from optically thin
free-free emission, and 17 fainter sources (J∼14-15) with [24] excess
consistent with a circumstellar disk. The frequency of IR excess for
the fainter sources increases from 4.5 to 24um. The IR excess is
likely due to debris from the planet formation process. The
wavelength-dependent behavior is consistent with an inside-out
clearing of circumstellar disks. A comparison of the 24um excess
population in h and χ Per sources with results for other clusters
shows that 24um emission from debris disks "rises" from 5 to 10Myr,
peaks at ∼10-15Myr, and then "falls" from ∼15-20Myr to 1Gyr.
Description:
We acquired MIPS 24um data using 80s exposures in scan mode,
covering two 0.3deg2 regions centered on the two clusters.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 128 616 MIPS sources with 2MASS/IRAC counterparts in
h+χ Persei
table2.dat 67 57 Stars/candidates and selected evolved stars
with 24um excess in h and χ Per
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See also:
J/ApJ/576/880 : CCD UBV photometry of h and χ Per (Slesnick+, 2002)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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2- 8 F7.4 deg RAdeg Right Ascension in decimal degrees (J2000) (1)
10- 16 F7.4 deg DEdeg Declination in decimal degrees (J2000) (1)
18- 23 F6.3 mag Vmag ?=99.000 The V band magnitude (2)
25- 30 F6.3 mag B-V ?=99.000 The (B-V) color index (2)
32- 37 F6.3 mag U-B ?=99.000 The (U-B) color index (2)
39- 44 F6.3 mag Jmag ?=99.000 2MASS J band magnitude (2)
46- 51 F6.3 mag Hmag ?=99.000 2MASS H band magnitude (2)
53- 58 F6.3 mag Ksmag ?=99.000 2MASS Ks band magnitude (2)
60- 65 F6.3 mag 3.6mag ?=99.000 IRAC 3.6 micron band magnitude (2)
67- 72 F6.3 mag 4.5mag ?=99.000 IRAC 4.5 micron band magnitude (2)
74- 79 F6.3 mag 5.8mag ?=99.000 IRAC 5.8 micron band magnitude (2)
81- 86 F6.3 mag 8.0mag ?=99.000 IRAC 8 micron band magnitude (2)
88- 93 F6.3 mag 24mag ?=99.000 MIPS 24 micron band magnitude (2)
95-100 F6.3 mag e_3.6mag ?=99.000 The 1σ error in 3.6mag (2)
102-107 F6.3 mag e_4.5mag ?=99.000 The 1σ error in 4.5mag (2)
109-114 F6.3 mag e_5.8mag ?=99.000 The 1σ error in 5.8mag (2)
116-121 F6.3 mag e_8.0mag ?=99.000 The 1σ error in 8.0mag (2)
123-128 F6.3 mag e_24mag ?=99.000 The 1σ error in 24mag (2)
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Note (1): Sources identified as [CKB2008] DD.dddd+DD.dddd in Simbad.
Note (2): Optical UBV photometry from Slesnick et al. (2002, Cat.
J/ApJ/576/880); errors in the 2MASS JHKs filters are ~<0.05 for
sources except the ∼21 fainter (J∼14-15) sources.
Values of 99.000 denote sources that were not observed in the given
filter at the 5σ level.
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- [CKB2008] Sequential number (1)
4- 7 I4 --- Num ?=99 Oosterhoff (1937AnLei..17a...1O 1937AnLei..17a...1O) number
9- 15 A7 --- SpType MK spectral type (2)
17- 23 F7.4 deg RAdeg Right Ascension in decimal degrees (J2000)
25- 31 F7.4 deg DEdeg Declination in decimal degrees (J2000)
33- 37 F5.2 mag Vmag ?=99.00 The V band magnitude
39- 43 F5.2 mag Jmag ?=99.00 2MASS J band magnitude
45- 49 F5.2 mag Hmag ?=99.00 2MASS H band magnitude
51- 55 F5.2 mag Ksmag ?=99.00 2MASS Ks band magnitude
57- 61 F5.2 mag 8.0mag ?=99.00 IRAC 8 micron band magnitude
63- 67 F5.2 mag 24mag ?=99.00 MIPS 24 micron band magnitude
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Note (1): The first twenty entries are confirmed Be stars from Bragg and
Kenyon (2002AJ....124.3289B 2002AJ....124.3289B) and have Oosterhoff (1937AnLei..17a...1O 1937AnLei..17a...1O)
numbers. Slesnick et al. (2002, Cat. J/ApJ/576/880) identify an
additional Be star in lower density regions surrounding the center of
h and χ Per (source number 23). All the other stars (referred to
as "candidate Be stars" in the text) are either supergiants,
foreground stars, or B-type cluster members from either Slesnick et
al. (source 21) or archived spectroscopic data from FAST (the five
other sources).
Note (2): All sources with the "e" designation in spectral type are Be stars.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Vannier [CDS] 06-Apr-2010