J/ApJ/769/10 Spectroscopy of M31 globular clusters (Jacoby+, 2013)
A survey for planetary nebulae in M31 globular clusters.
Jacoby G.H., Ciardullo R., De Marco O., Lee M.G., Herrmann K.A.,
Hwang H.S., Kaplan E., Davies J.E.
<Astrophys. J., 769, 10 (2013)>
=2013ApJ...769...10J 2013ApJ...769...10J
ADC_Keywords: Clusters, globular ; Photometry, CMT1T2V ; Radial velocities ;
Equivalent widths ; Planetary nebulae
Keywords: galaxies: individual: M31; globular clusters: general;
planetary nebulae: general; stars: evolution
Abstract:
We report the results of an [OIII]λ5007 spectroscopic survey
for planetary nebulae (PNe) located within the star clusters of M31.
By examining R∼5000 spectra taken with the WIYN+Hydra spectrograph, we
identify 3 PN candidates in a sample of 274 likely globular clusters,
2 candidates in objects which may be globular clusters, and 5
candidates in a set of 85 younger systems. The possible PNe are all
faint, between ∼2.5 and ∼6.8mag down the PN luminosity function, and,
partly as a consequence of our selection criteria, have high
excitation, with [OIII]λ5007 to Hβ ratios ranging from 2
to ≳12. We discuss the individual candidates, their likelihood of
cluster membership, and the possibility that they were formed via
binary interactions within the clusters. Our data are consistent with
the suggestion that PN formation within globular clusters correlates
with binary encounter frequency, though, due to the small numbers and
large uncertainties in the candidate list, this study does not provide
sufficient evidence to confirm the hypothesis.
Description:
On 2008 October 25-28 (UT), we targeted 467 candidate star clusters in
M31 with the 3.5m WIYN telescope on Kitt Peak and the Hydra
multi-fiber spectrograph. The spectra covered the wavelength range
between 4400Å and 5450Å at 1Å resolution and 0.5Å/pixel.
Table 3 lists all the cluster candidates surveyed in this program,
along with their Washington system photometry obtained with the KPNO
0.9m telescope (Kim et al. 2007, Cat. J/AJ/134/706).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 140 461 Globular cluster observations
table4.dat 77 14 Clusters with candidate planetary nebulae
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See also:
V/143 : Revised Bologna Catalog of M31 clusters, V.5 (Galleti+ 2012)
J/AJ/148/4 : JHK photometry of 913 globular clusters in M31 (Wang+, 2014)
J/AJ/147/16 : Spectroscocpy of planetary nebulae in M31 (Kniazev+, 2014)
J/AJ/146/20 : Structural param. for globular clusters in M31 (Wang+, 2013)
J/A+A/549/A60 : Ages and [Fe/H] of M31 globular clusters (Cezario+, 2013)
J/A+A/544/A155 : HST photometry of M31 globular clusters (Federici+, 2012)
J/AJ/143/87 : IRAC phot. of massive M31 globular clusters (Barmby+, 2012)
J/AJ/143/14 : Lick indices of M31 globular clusters (Schiavon+, 2012)
J/ApJS/199/37 : GALEX catalog of star clusters in M31 (Kang+, 2012)
J/A+A/534/A55 : Deep XMM-Newton Survey of M31 (Stiele+, 2011)
J/AJ/141/61 : Star clusters in M31. II. (Caldwell+, 2011)
J/AJ/140/1043 : Globular clusters in M31 & the Galaxy (van den Bergh+, 2010)
J/MNRAS/402/803 : M31 globular cluster system (Peacock+, 2010)
J/ApJ/704/385 : M31 integrated light abundances (Colucci+, 2009)
J/ApJ/703/1872 : Compact star clusters in the M31 disk (Vansevicius+, 2009)
J/A+A/508/1285 : Metallicity estimates of M31 GCs (Galleti+, 2009)
J/AJ/138/1667 : HST survey of young clusters in M31. III. (Barmby+, 2009)
J/AJ/137/94 : Star clusters in M31 (Caldwell+, 2009)
J/ApJS/177/174 : Star clusters in M31 (Narbutis+, 2008)
J/AJ/134/706 : New globular clusters in M 31 (Kim+, 2007)
J/AJ/133/2764 : M31 globular clusters structural parameters (Barmby+, 2007)
J/A+A/471/127 : New globular clusters in M31 (Galleti+, 2007)
J/ApJS/173/643 : GALEX UV photometry of M31 Globular Clusters (Rey+, 2007)
J/A+A/456/985 : Radial velocities of M31 candidate clusters (Galleti+, 2006)
J/A+A/449/143 : Photometry of M31 globular cluster candidates (Ma+, 2006)
J/MNRAS/369/120 : Kinematic survey of planetary nebulae in M31 (Merrett+, 2006)
J/A+A/416/917 : Revised Bologna Catalog of M31 GCs (Galleti+, 2004)
J/ApJ/616/804 : Planetary Nebula Kinematics in M31 (Hurley-Keller+, 2004)
J/AJ/123/2490 : RV and [Fe/H] of M31 globular cluster system (Perrett+, 2002)
J/AJ/119/727 : M31 globular clusters photometry (Barmby+, 2000)
J/AcA/48/455 : Globular Clusters in M31 and M33 (Mochejska+, 1998)
J/AJ/114/1488 : Globulars in M31 (Holland+ 1997)
J/A+AS/116/447 : M31 globulars clusters ellipticities (Staneva+, 1996)
http://www.cfa.harvard.edu/oir/eg/m31clusters/M31_Hectospec.html : N. Caldwell
M31 cluster web site
Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Name Globular cluster name
13- 20 A8 --- OName Globular cluster other name
22- 27 F6.3 mag T1mag [13.5/20]? Washington system T1 band magnitude
28 A1 --- f_T1mag T1mag derived from literature values (1)
30- 34 F5.3 mag e_T1mag ? Uncertainty in T1mag
37- 42 F6.3 mag Cmag [15/23.2]? Washington system C band magnitude
43 A1 --- f_Cmag Cmag derived from literature values (1)
45- 49 F5.3 mag e_Cmag ? Uncertainty in Cmag
52- 57 F6.3 mag Mmag [14.4/21]? Washington system M band magnitude
58 A1 --- f_Mmag Mmag derived from literature values (1)
60- 64 F5.3 mag e_Mmag [0.001/0.8]? Uncertainty in Mmag
66- 71 F6.1 km/s RVel [-713/46]? Radial velocity
73- 78 F6.1 km/s e_RVel [1.7/133]? Uncertainty in RVel
80- 91 A12 --- Type Source classification: Galaxy, HII, Star, or
age population (Young, Intermediate, Old)
93 A1 --- r_Type Reference for Type (2)
95 A1 --- l_O/Hb Limit flag on O/Hb
96-100 F5.1 --- O/Hb [0/12]? Derived [OIII]/Hβ ratio (3)
101 A1 --- u_O/Hb Uncertainty flag on [OIII]/Hβ ratio
103 A1 --- l_EW Limit flag on EW
104-110 F7.3 0.1nm EW [0/370]? Equivalent width of [OIII] (Å)
112-138 A27 --- Notes Additional notes on spectrum
140 A1 --- n_Type Remarks about the classification (4)
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Note (1): Indicates values have been transformed into the Washington system
using literature BVI measurements and the relations of Bessell
(2001PASP..113...66B 2001PASP..113...66B).
Note (2): Reference as follows:
1 = Strader et al. (2011AJ....142....8S 2011AJ....142....8S);
2 = Caldwell et al. (2011, J/AJ/141/61);
3 = Caldwell et al. (2009, J/AJ/137/94);
4 = Peacock et al. (2010, J/MNRAS/402/803).
Note (3): Using the procedures described in Section 2.
Note (4): Flag as follows:
d = Classified on the basis of an emission line a 5046Å.
e = Classified on the basis of a 50Å FWHM logarithmic-profile
emission line at 4836Å.
f = Classified on the basis of weak emission at 4548Å.
g = Both [OIII]λ5007 and Hβ are well resolved and have the
same double-peaked emission profile.
h = Classified using the redshifted emission lines of Hβ and the
[OIII] doublet.
i = Classified as a galaxy in the literature, but our spectrum is
consistent with the object being a star cluster.
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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 --- Type Cluster type (1)
4- 11 A8 --- Name Globular cluster name
13- 20 A8 --- OName Globular cluster other name
22- 27 A6 --- PN PN name
29 A1 --- r_Age [c] Age from Beasley et al. (2)
31- 34 F4.1 Gyr Age [0.3/14]? Age (3)
36 A1 --- f_Age Flag on Age (4)
38- 42 F5.2 mag VMag [-9.63/-4.4] Absolute V-band magnitude
44- 47 F4.1 --- S/N [3/72]? Signal-to-noise ratio ([OIII]5007Å)
49- 52 F4.1 --- S/N(Hb) [1/16]? Signal-to-noise ratio (Hβ)
54 A1 --- l_O/Hb Limit flag on O/Hb
56- 59 F4.1 --- O/Hb [2/50] Ratio of [OIII] to Hβ
61- 63 F3.1 0.1nm EW [0.5/2.5]? [OIII] equivalent width (Å)
65- 68 F4.1 --- M5007 [-3.3/5.1] Absolute 5007Å magnitude (5)
70- 72 I3 km/s Dv [-34/59] Difference, Δv, between the PN
emission-line radial velocity and the
absorption-line radial velocity of the
cluster's stars
74- 77 F4.2 --- Dv/sig [0.1/3] Significance of Dv (6)
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Note (1): Type as follow:
GC = Globular cluster
yC = Young cluster
pC = Possible cluster
MW = Milky Way cluster
Note (2):
c = Age from Beasley et al. (2005AJ....129.1412B 2005AJ....129.1412B); emission may be warm ISM.
Note (3): Age estimate of Caldwell+ (2009, J/AJ/137/94; 2011, J/AJ/141/61).
Objects flagged "s" were classified by Peacock et al. (2010,
J/MNRAS/402/803).
Note (4): Code as follows:
s = "star"
o = old
y = young
Note (5): To estimate the [OIII]5007 magnitudes of the PNe, we used our
knowledge of the 5000Å continuum brightness of each cluster, as
determined by its Washington system M magnitude (central wavelength
5075Å). By measuring the strength of [OIII]5007 relative to this
continuum, i.e., the line's equivalent width, we could approximate the
PN candidate's 5007Å monochromatic flux. This flux was then
converted to a magnitude via Eq.(3): m5007=-13.74-2.5logF5007 and
placed on an absolute scale by assuming a distance of 750kpc (Freedman
et al. 2001ApJ...553...47F 2001ApJ...553...47F) and a differential extinction E(B-V)=0.062
(Schlegel et al. 1998ApJ...500..525S 1998ApJ...500..525S).
Note (6): significance Δv/σeff , where σeff is the
quadrature sum of the system's internal velocity dispersion and the
uncertainty in the radial velocity measurements. See section 3.3 for
further explanations.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 01-Dec-2014