J/ApJ/705/1646 Debris disks in Upper Sco (Carpenter+, 2009)
Debris disks in the upper Scorpius OB association.
Carpenter J.M., Mamajek E.E., Hillenbrand L.A., Meyer M.R.
<Astrophys. J., 705, 1646-1671 (2009)>
=2009ApJ...705.1646C 2009ApJ...705.1646C
ADC_Keywords: Associations, stellar ; Photometry, infrared ;
Stars, pre-main sequence
Keywords: circumstellar matter - open clusters and associations: individual
(Upper Scorpius) - planetary systems: formation -
planetary systems: protoplanetary disks - stars: pre-main sequence
Abstract:
We present MIPS 24um and 70um photometry for 205 members of the Upper
Scorpius OB Association. These data are combined with published MIPS
photometry for 15 additional association members to assess the
frequency of circumstellar disks around 5Myr old stars with spectral
types between B0 and M5. Twelve stars have a detectable 70um excess,
each of which also has a detectable 24um excess. A total of 54 stars
are identified with a 24um excess more than 32% above the stellar
photosphere. The MIPS observations reveal 19 excess sources - 8 A/F/G
stars and 11 K/M stars - that were not previously identified with an
8um or 16um excess. The lack of short-wavelength emission and the weak
24um excess suggests that these sources are debris systems or the
remnants of optically thick primordial disks with inner holes. Despite
the wide range of luminosities of the stars hosting apparent debris
systems, the excess characteristics are consistent with all stars
having dust at similar orbital radii after factoring in variations in
the radiation blowout particle size with spectral type. The results
for Upper Sco are compared to similar photometric surveys from the
literature to re-evaluate the evolution of debris emission.
Description:
The selection criteria for the Upper Sco sample are described in Paper
I (Carpenter et al., 2006, Cat J/ApJ/651/L49). In Paper I, IRAC (4.5um
and 8um) and IRS peak-up (16um) photometry was presented for 218 of
the 220 stars. We present here Spiter/MIPS 24um and 70um photometry
for 205 stars observed in Upper Sco. MIPS photometry for the remaining
15 stars are listed in Carpenter et al. (2008ApJS..179..423C 2008ApJS..179..423C).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 71 205 MIPS 24 and 70 micron photometry
table2.dat 81 220 Normalized Flux Ratios
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See also:
J/MNRAS/374/372 : ZYJHK photometry in Upper Sco (Lodieu+, 2007)
J/MNRAS/373/95 : ZYJHK survey of Upper Sco association (Lodieu+, 2006)
J/ApJ/651/L49 : Upper Sco OB association IRAC observations (Carpenter+, 2006)
J/AJ/124/404 : Upper Scorpius OB association Lithium survey. II. (Preibisch,
2002)
J/AJ/121/1040 : PMS members of upper Sco OB association (Preibisch+, 2001)
J/A+A/333/619 : Upper Sco OB association Lithium survey (Preibisch+ 1998)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 31 A31 --- Name Source name (1)
33- 39 F7.2 mJy S24 Spitzer/MIPS 24 micron band flux density (2)
41- 45 F5.2 mJy e_S24 The 1σ uncertainty in S24
47- 52 F6.1 mJy S70 Spitzer/MIPS 70 micron band flux density (3)
54- 58 F5.1 mJy e_S70 The 1σ uncertainty in S70
60- 67 I8 --- AORKey Spitzer Astronomical Observation Request (AOR)
identification number
69- 71 A3 --- Flags [1-6, ] Flags concerning the photometry (4)
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Note (1): Source names with the prefix [PZ99] and [PBB2002] are from
Preibisch & Zinnecker (1999AJ....117.2381P 1999AJ....117.2381P) and Preibisch et al.
(2002, Cat. J/AJ/124/404) respectively.
Note (2): Measured using a flux calibration factor of 0.0447MJy/sr.
Note (3): Measured using a flux calibration factor of 702MJy/sr.
Note (4): Flag as follows:
1 = 24 micron photometry is unreliable due to bright, extended nebulosity.
2 = 24 micron photometry is unreliable due to nearby star.
3 = Source is extended at 24 micron
4 = 70 micron photometry is unreliable due to contaminating source
or nebulosity.
5 = Contaminating source(s) subtracted before 70 micron photometry
was measured.
6 = 70 micron photometry measured on AOR 13903104.
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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- 31 A31 --- Name Source name
33- 40 A8 --- SpType MK spectral type
42 I1 --- r_SpType Reference for SpType (1)
44- 46 F3.1 --- AV The V band extinction
48- 53 F6.2 --- R24 Ratio of 24 micron observed to photospheric
flux density
55- 60 F6.1 --- R70 Ratio of 70 micron observed to photospheric
flux density
62- 66 F5.1 --- e_R70 The 1σ uncertainty in R70
68 A1 --- E24 [Y]? Excess at 24 micron?
70 A1 --- E70 [Y]? Excess at 70 micron?
72- 81 A10 --- Type Disk type (debris, primordial or Be)
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Note (1): Reference as follows:
1 = Houk (Cat. III/80)
2 = Houk & Smith-Moore (Cat. III/133)
3 = Kunkel (1999, PhD thesis, Julius-Maximilians-Universitat Wurzburg);
4 = E. Mamajek, private communication;
5 = Preibisch et al. (1998, Cat. J/A+A/333/619);
6 = Preibisch et al. (2001, Cat. J/AJ/121/1040);
7 = Preibisch et al. (2002, Cat. J/AJ/124/404);
8 = Walter et al. (1994AJ....107..692W 1994AJ....107..692W).
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History:
From electronic version of the journal
References:
Carpenter et al. Paper I. Cat. J/ApJ/651/L49 . 2006ApJ...651L..49C 2006ApJ...651L..49C
Carpenter et al. Spitzer legacy science database. 2008ApJS..179..423C 2008ApJS..179..423C
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 08-Dec-2011