J/AJ/137/4282 Red giant stars in clusters. II. M13 and M92 (Meszaros+, 2009)
Mass outflow and chromospheric activity of red giant stars in globular clusters.
II. M13 and M92.
Meszaros SZ., Dupree A.K., Szalai T.
<Astron. J., 137, 4282-4295 (2009)>
=2009AJ....137.4282M 2009AJ....137.4282M
ADC_Keywords: Stars, giant ; Photometry, infrared ; Photometry, UBV ;
Radial velocities ; Spectroscopy ; Clusters, globular
Keywords: globular clusters: general - stars: AGB and post-AGB -
globular clusters: individual (M13, M15, M92, NGC 2808) -
stars: chromospheres - stars: mass loss
Abstract:
High-resolution spectra of 123 red giant stars in the globular cluster
M13 and 64 red giant stars in M92 were obtained with Hectochelle at
the MMT telescope. Emission and line asymmetries in Hα and CaIIK
are identified, characterizing motions in the extended atmospheres and
seeking differences attributable to metallicity in these clusters and
M15. On the red giant branch, emission in Hα generally appears
in stars with Teff≲4500K and logL/L☉≳2.75. Fainter stars
showing emission are asymptotic giant branch (AGB) stars or perhaps
binary stars. The line-bisector for Hα reveals the onset of
chromospheric expansion in stars more luminous than
log(L/L☉)∼2.5 in all clusters, and this outflow velocity
increases with stellar luminosity. However, the coolest giants in the
metal-rich M13 show greatly reduced outflow in Hα most probably
due to decreased Teff and changing atmospheric structure. The
CaIIK3 outflow velocities are larger than shown by Hα at the
same luminosity and signal accelerating outflows in the chromospheres.
Stars clearly on the AGB show faster chromospheric outflows in Hα
than RGB objects. While the Hα velocities on the RGB are similar
for all metallicities, the AGB stars in the metal-poor M15 and M92
have higher outflow velocities than in the metal-rich M13. Comparison
of these chromospheric line profiles in the paired metal-poor
clusters, M15 and M92, shows remarkable similarities in the presence
of emission and dynamical signatures, and does not reveal a source of
the "second-parameter" effect.
Description:
A total of 123 different red giant stars in M13 and 64 red giants in
M92 were observed in 2006 March and 2006 May, with Hectochelle on the
MMT.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 89 123 Photometric data of observed cluster members in M13
table2.dat 87 64 Photometric data of observed cluster members in M92
table5.dat 44 123 Physical parameters of cluster members in M13
table6.dat 44 64 Physical parameters of cluster members in M92
table7.dat 30 270 Radial and Hα bisector velocity of
observed stars in M13
table8.dat 30 121 Radial and Hα bisector velocity of
observed stars in M92
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See also:
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
II/248 : UBV photometry and proper motions in M13 (Kadla, 1966)
IV/26 : Hercules Messier 13 (M13) photometry (Ludendorff, 1905)
J/AJ/133/1041 : Velocities and CMT photometry in globular M92 (Drukier+, 2007)
J/AJ/135/1117 : Red giant stars in globular clusters. I. M15 (Meszaros+, 2008)
Byte-by-byte Description of file: table[12].dat
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Bytes Format Units Label Explanations
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1- 7 A7 --- ID Identification number (1)
9- 10 I2 h RAh 2MASS Hour of Right Ascension (J2000)
12- 13 I2 min RAm 2MASS Minute of Right Ascension (J2000)
15- 20 F6.3 s RAs 2MASS Second of Right Ascension (J2000)
22 A1 --- DE- 2MASS Sign of the Declination (J2000)
23- 24 I2 deg DEd 2MASS Degree of Declination (J2000)
26- 27 I2 arcmin DEm 2MASS Arcminute of Declination (J2000)
29- 33 F5.2 arcsec DEs 2MASS Arcsecond of Declination (J2000)
35- 39 F5.2 mag Bmag The B band magnitude (G2)
41- 45 F5.2 mag Vmag The V band magnitude (G2)
47- 52 F6.3 mag Jmag 2MASS J band magnitude
54- 59 F6.3 mag Hmag 2MASS H band magnitude
61- 66 F6.3 mag Ksmag 2MASS KS band magnitude
68- 71 F4.2 mag B-V The (B-V) color index
73- 77 F5.3 mag V-Ks The (V-KS) color index
79- 89 A11 --- Obs Observation date code (G1)
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Note (1): Identifications are:
* For table 1 (M13):
LNNNN = Ludendorff (1905, Cat. IV/26, in Simbad).
KNNN = Kadla (1966, Cat. II/248, <Cl* NGC 6205 KAD NNN> in Simbad).
III-65 = Cl* NGC 6205 ARP III-65 from Arp, 1955AJ.....60..317A 1955AJ.....60..317A.
* For table2 (M92):
from Sandage & Walker, 1966ApJ...143..313S 1966ApJ...143..313S, in Simbad
where NNNNN = R*1000 + Seq if 'R' is the region (I to XII)
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Byte-by-byte Description of file: table[56].dat
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Bytes Format Units Label Explanations
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1- 7 A7 --- ID Identification number
9- 13 F5.2 mag VMAG Absolute V band magnitude
15- 18 F4.2 mag (B-V)0 Intrinsic (B-V) color index
20- 24 F5.3 mag (V-K)0 Intrinsic (V-K) color index
26- 27 I2 % Mm Membership probability (G2)
29- 32 I4 K Teff Effective temperature
34- 38 F5.3 [solLum] logL Log luminosity
40- 44 F5.1 solRad Rad Radius
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Byte-by-byte Description of file: table[78].dat
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Bytes Format Units Label Explanations
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1- 7 A7 --- ID Identification number
9- 14 F6.1 km/s RV ? Measured radial velocity
16- 18 F3.1 km/s e_RV ? Uncertainty in VRad
20- 24 F5.1 km/s Va ? Hα bisector asymetry velocity
26- 28 F3.1 km/s e_Va ? Uncertainty in Va
30 A1 --- Obs Observation code (G1)
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Global Notes:
Note (G1): Observation code as follows (1-6 for M13, A-E for M92):
1 = 2006 March 14 (OB25: Hα, region used for analysis 6475-6630);
2 = 2006 May 10 (OB25);
3 = 2006 March 16 (RV31: region used for analysis 5150-5300);
4 = 2006 May 10 (RV31);
5 = 2006 March 16 (Ca41: CaII H&K, region used for analysis 3910-3990);
6 = 2006 May 10 (Ca41).
A = 2006 May 7 (OB25);
B = 2006 May 9 (OB25);
C = 2006 May 7 (RV31);
D = 2006 May 8 (Ca41);
E = 2006 May 9 (Ca41).
Note (G2): Photometry and membership probability from
* Cudworth & Monet, 1979AJ.....84..774C 1979AJ.....84..774C for M13
* Cudworth, 1976AJ.....81..975C 1976AJ.....81..975C for M92.
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History:
From electronic version of the journal
29-Jul-2010: insert into VizieR
18-Nov-2010: K246 is a misprint for K465; corrected in table 1, 5 and 7.
References:
Meszaros et al., Paper I, 2008AJ....135.1117M 2008AJ....135.1117M. Cat. J/AJ/135/1117
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 28-Jun-2010