J/MNRAS/428/2118 Binarity in planetary nebula central stars (De Marco+ 2013)
The binary fraction of planetary nebula central stars.
I. A high-precision, I-band excess search.
De Marco O., Passy J.-C., Frew D.J., Moe M., Jacoby G.H.
<Mon. Not. R. Astron. Soc., 428, 2118-2140 (2013)>
=2013MNRAS.428.2118D 2013MNRAS.428.2118D
ADC_Keywords: Planetary nebulae ; Stars, double and multiple ; Photometry, UBVRI
Keywords: techniques: photometric - binaries: general - stars: evolution -
white dwarfs - planetary nebulae: general
Abstract:
We still do not know what causes aspherical planetary nebula (PN)
morphologies. A plausible hypothesis is that they are due to the
presence of a close stellar or substellar companion. So far, only ∼40
binary central stars of PN have been detected, almost all of them with
such short periods that their binarity is revealed by photometric
variability. Here we have endeavoured to discover binary central stars
at any separation, thus determining the unbiased binary fraction of
central stars of PN. This number, when compared to the binary fraction
of the presumed parent population, can give a first handle on the
origin of PN. By detecting the central stars in the I band we
have searched for cool companions.
Description:
The sample presented here consists of 30 central stars of PN which
were selected solely based on their low PN surface brightness (radius
of the PN is larger than ∼25arcsec in most cases) as well as on the
faint V magnitudes of their central stars.
The observations were acquired during eight nights between 2007
October 30 and November 6 at the 2.1-m telescope at the Kitt Peak
National Observatory. However, the data from nights 2 and 8 were not
photometric.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table6.dat 72 31 The photometric magnitudes of our targets rounded
to three decimal places
table3.dat 98 78 Log of observations taken in photometric conditions
tablea1.dat 66 76 The individual photometric magnitudes for our sample
of PN central stars (including three PN mimics)
tableb1.dat 65 78 *Predicted colours of single post-AGB stars using
TMAP models as well as for blackbody curves (BB)
tablec1.dat 58 41 Spectral types, empirical V-band absolute
magnitudes, intrinsic colour indices and masses of
main-sequence stars
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Note on tableb1.dat: TMAP models: TMAW with solar metallicity - see the text,
or TheoSSA, where the model atom and abundances are indicated as mass
fractions adjacent to the relevant atom. These values have been adjusted for
the small corrections of 0.010mag for the B-V and R-I colours and -0.002mag
for the V-I colours.
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See also:
J/A+A/496/813 : Binary PNe towards the Galactic bulge (Miszalski+, 2009)
Byte-by-byte Description of file: table6.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- Name Planetary nebula name
9 A1 --- n_Name [a] a : measurements obtained by excluding
observations taken on night 3
11- 16 F6.3 mag Bmag Average Johnson B magnitude
18- 22 F5.3 mag e_Bmag rms uncertainty on Bmag (1)
24 I1 --- o_Bmag Number of observations in Bmag
27- 32 F6.3 mag Vmag Average Johnson V magnitude
34- 38 F5.3 mag e_Vmag rms uncertainty on Vmag (1)
40 I1 --- o_Vmag Number of independent exposures in V used to
calculate the final photometric magnitude
43- 48 F6.3 mag Rcmag Average Cousins R magnitude
50- 54 F5.3 mag e_Rcmag rms uncertainty on Rcmag (1)
56 I1 --- o_Rcmag Number of independent exposures in Rc used to
calculate the final photometric magnitude
59- 64 F6.3 mag Icmag Average Cousins I magnitude
66- 70 F5.3 mag e_Icmag rms uncertainty on Icmag (1)
72 I1 --- o_Icmag Number of independent exposures in Ic used to
calculate the final photometric magnitude
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Note (1): Formal errors lower than 1% were set at 1%.
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- Name Planetary nebula name
11- 12 I2 h RAh Right ascension (J2000)
14- 15 I2 min RAm Right ascension (J2000)
17- 21 F5.2 s RAs Right ascension (J2000)
23 A1 --- DE- Declination sign (J2000)
24- 25 I2 deg DEd Declination (J2000)
27- 28 I2 arcmin DEm Declination (J2000)
30- 33 F4.1 arcsec DEs Declination (J2000)
35- 37 I3 s t(B) Exposure time in B band
39- 41 I3 s t(V) Exposure time in V band
43- 45 I3 s t(Rc) Exposure time in Rc band
47- 49 I3 s t(Ic) ? Exposure time in Ic band
51- 53 I3 s t(Ic2) ? Second exposure time in Ic band
55- 59 A5 "h:m" ObsTime UT time of the observation
61- 70 A10 "date" ObsDate UT date of the observation
72 I1 --- Night Night number
74- 98 A25 --- Com Comments
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Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- Name Planetary nebula name (1)
10 I1 --- Night Night number (2)
12- 17 F6.3 mag Bmag Johnson B magnitude
19- 24 F6.3 mag Vmag Johnson V magnitude
26- 31 F6.3 mag Rcmag Cousins R magnitude
33- 38 F6.3 mag Icmag ?=- Cousins I magnitude
40- 44 F5.3 mag e_Bmag rms uncertainty on Bmag
46- 50 F5.3 mag e_Vmag rms uncertainty on Vmag
52- 56 F5.3 mag e_Rcmag rms uncertainty on Rcmag
58- 62 F5.3 mag e_Icmag ?=- rms uncertainty on Icmag
64- 66 F3.1 --- AirM Airmass
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Note (1): DeHt 5 and HDW 4, having only one epoch of data, are reported only
in Table 6.
Note (2): The date and time corresponding to each night can be found in Table 3.
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Byte-by-byte Description of file: tableb1.dat
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Bytes Format Units Label Explanations
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1- 3 I3 kK Teff [20/170] Effective temperature
5- 7 F3.1 mag logg [4/8] Surface gravity
9- 14 F6.3 mag B-V B-V colour index
16- 21 F6.3 mag V-I V-I colour index
22 A1 --- n_V-I [a] Interpolated color (1)
24- 29 F6.3 mag V-J V-J colour index
31- 36 F6.3 mag R-I R-I colour index
38- 43 F6.3 mag J-H J-H colour index
45- 65 A21 --- Abund Abundance(s) (2)
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Note (1): a = This colour was interpolated between the values for the
110 and 130kK atmospheres.
Note (2): Abundances are specified by their mass franction. The TMAW
stellar atmosphere models are calculated for a solar composition
with mass fractions H0.71 He0.28 C0.001 N0.002 O0.006
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Byte-by-byte Description of file: tablec1.dat
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Bytes Format Units Label Explanations
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1- 3 A3 --- SpT MK spectral type (all dwarfs)
5- 10 F6.2 mag VMag Absolute V magnitude
12- 16 F5.2 mag (U-B)0 ?=- Intrincic U-B colour index
17 A1 --- u_(U-B)0 Uncertainty flag on (U-B)0
19- 23 F5.2 mag (B-V)0 ?=- Intrincic B-V colour index
25- 29 F5.2 mag (V-Rc)0 Intrincic V-Rc colour index
31- 35 F5.2 mag (V-Ic)0 Intrincic V-Ic colour index
37- 41 F5.2 mag (V-J)0 Intrincic V-J colour index
43- 47 F5.2 mag (V-H)0 Intrincic V-H colour index
49- 53 F5.2 mag (V-Ks)0 Intrincic V-Ks colour index
55- 58 F4.2 Msun Mass Mass on main-sequence
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 31-Jan-2014