J/MNRAS/365/401 New planetary nebulae in LMC (Reid+, 2006)
A new population of planetary nebulae discovered in the Large Magellanic Cloud -
I. Preliminary sample.
Reid W.A., Parker Q.A.
<Mon. Not. R. Astron. Soc., 365, 401-413 (2006)>
=2006MNRAS.365..401R 2006MNRAS.365..401R
ADC_Keywords: Magellanic Clouds - Planetary nebulae ; Photometry, H-alpha
Keywords: planetary nebulae: general - Magellanic Clouds
Abstract:
We report our initial discovery of 73 new planetary nebulae (PNe)
in the Large Magellanic Cloud (LMC) following confirmatory 2dF
spectroscopy on the Anglo-Australian Telescope. Preliminary candidate
sources come from a 10 per cent sub-area of our new deep,
high-resolution Hα map of the central 25deg2 of the LMC
obtained with the UK Schmidt Telescope. The depth of the
high-resolution map was extended to Requiv∼22 for Hα
(4.5x10-17erg/cm2/s/Å) by a process of multi-exposure median
co-addition of a dozen 2-h Hα exposures. The resulting map is at
least 1-mag deeper than the best wide-field narrow-band LMC images
currently available. This depth, combined with our selection
technique, has also led to the discovery of extended asymptotic giant
branch (AGB) haloes around many new and previously known LMC PNe for
the first time. Once complete, our new survey is expected to triple
the LMC PN population and have significant implications for the LMC PN
luminosity function, kinematics, abundance gradients, chemical
evolution and, via study of the AGB haloes, the initial to final mass
relation for low- to intermediate-mass stars.
Description:
Over the last few years, we have specially constructed additional
deep, homogeneous, narrow-band H and matching broad-band 'SR' (Short
Red) maps of the entire central 25deg2 of the LMC. These unique maps
were obtained from co-adding 12 well-matched UKST 2-h Hα
exposures and six 15-min equivalent SR-band exposures on the same
field using high-resolution Tech-Pan film. The 'SuperCOSMOS'
plate-measuring machine at the Royal Observatory Edinburgh (Hambly et
al., 2001MNRAS.326.1279) has scanned, co-added and pixel-matched these
exposures, creating 10-m (0.67-arcsec) pixel data which goes 1.35 and
1mag deeper than individual exposures, achieving the full canonical
Poissonian depth gain, e.g. Bland-Hawthorn, Shopbell & Malin
(1993AJ....106.2154B 1993AJ....106.2154B). This gives a depth ∼21.5 for the SR images and
Requiv∼22 for Hα (4.5x10-17erg/cm2/s/Å) which is at
least 1-mag deeper than the best wide-field narrow-band LMC images
currently available.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 94 31 Previously known PN within the spectroscopically
confirmed fields
table4.dat 94 73 Newly discovered PN within the spectroscopically
confirmed fields
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See also:
J/MNRAS/362/689 : AAO/UKST SuperCOSMOS Hα survey (Parker+, 2005)
http://www-wfau.roe.ac.uk/sss/halpha : SuperCOSMOS Hα survey Home Page
Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 6 A6 --- Name Object name (1)
8- 26 A19 --- OName Other catalogue names (1)
28- 29 I2 h RAh Right ascension (J2000)
31- 32 I2 min RAm Right ascension (J2000)
34- 38 F5.2 s RAs Right ascension (J2000)
40 A1 --- DE- Declination sign (J2000)
41- 42 I2 deg DEd Declination (J2000)
44- 45 I2 arcmin DEm Declination (J2000)
47- 51 F5.2 arcsec DEs Declination (J2000)
53- 63 A11 --- CPNO Central PN observed
65- 68 F4.1 arcsec SR ? Short-red dimension
69 A1 --- --- [x]
70- 72 F3.1 arcsec SR2 ? Second SR dimension when not circular
74- 77 F4.1 arcsec Ha ? Hα dimension
78 A1 --- --- [x]
79- 82 F4.1 arcsec Ha2 ? Second Hα dimension when not circular
84- 87 F4.2 --- I([NII]/Ha) ? [N II]/Hα intensity
90- 93 F4.1 mag SRmag ? Short-red magnitude
94 A1 --- n_SRmag [a] Note on SRmag (G1)
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Note (1): Catalogue abbreviations used are:
LI : Lindsay (1963IrAJ....6..127L 1963IrAJ....6..127L) [L63] NNN in Simbad
LM1, ML2 : Lindsay & Mullan (1963IrAJ....6...51L 1963IrAJ....6...51L) LM 1-NN, LM 2-NN
MG : Morgan & Good (1992A&AS...92..571M 1992A&AS...92..571M) , MGPN LMC NN
Mo : Morgan (1994A&AS..103..235M 1994A&AS..103..235M), [M94b] NN
N : Henize (1956ApJS....2..315H 1956ApJS....2..315H), LHA 120-S NNN
SMP : Sanduleak et al. (1978PASP...90..621S 1978PASP...90..621S), SMP LMC NNN
Sa : Sanduleak (1984IAUS..108..231S 1984IAUS..108..231S), SMP LMC NNNA
WS : Westerlund & Smith (1964MNRAS.127..449W 1964MNRAS.127..449W), WSPN NN
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 2 A2 --- --- [RP]
3- 6 I4 --- [RP2006] Sequential number
8- 24 A17 --- RPJ RP JHHMMSS+DDMMSS designation (1)
28- 29 I2 h RAh Right ascension (J2000)
31- 32 I2 min RAm Right ascension (J2000)
34- 38 F5.2 s RAs Right ascension (J2000)
40 A1 --- DE- Declination sign (J2000)
41- 42 I2 deg DEd Declination (J2000)
44- 45 I2 arcmin DEm Declination (J2000)
47- 51 F5.2 arcsec DEs Declination (J2000)
53- 63 A11 --- CPNO Central PN observed
65- 68 F4.1 arcsec SR ? Short-red dimension
69 A1 --- --- [x]
70- 72 F3.1 arcsec SR2 ? Second SR dimension when not circular
74- 77 F4.1 arcsec Ha ? Hα dimension
78 A1 --- --- [x]
79- 82 F4.1 arcsec Ha2 ? Second Hα dimension when not circular
84- 88 F5.3 --- I([NII]/Ha) ? [N II]/Hα intensity
90- 93 F4.1 mag SRmag ? Short-red magnitude
94 A1 --- n_SRmag [a] Note on SRmag (G1)
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Note (1): [RP2006] JHHMMSS+DDMMSS in Simbad
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Global notes:
Note (G1): a: PNe magnitudes for which manual de-blended image photometry was
performed
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 09-May-2006