VII/13 Globular-Cluster Catalog (Arp 1965)
Globular-Cluster Catalog
Arp H.C.
<Stars and Stellar Systems, Vol. 5, gen. ed. G.P. Kuiper,
eds. A. Blaauw and M. Schmidt, Chapter 19, p. 410. (1965)>
ADC_Keywords: Clusters, globular - 220
Description:
This catalog is the Globular Cluster Catalog published by
Halton C. Arp in 1965 as part of a review paper on globular
Clusters. The review focused on the slightly more than a
hundred roughly spherical star clusters that have integrated
color indices between B-V = 0.6 an 0.8 mag and intrinsic
magnitudes between Mbol = -4 and -10 mag. They are distributed
about the center of the galaxy. Such clusters contain stars that
are very old and metal poor. The catalog improves upon the earlier
publication by Mrs. Hogg (1959). An estimate of the completeness
of the catalog is 98 percent complete for galactic latitudes
above b(II)=8 degrees and 94 percent complete for low latitudes
for concentration classes less than XI. This catalog lists
for all 119 clusters: the NGC number, or other ID, the name, the
position in equatorial and galactic coordinates, the concentration
class, galactic absorption, diameter at 0.9, magnitude of 25-st
brightest star, distance modulus, galactic radius, x, y, and z
positions, total brightness, apparent and intrinsic colors,
spectral type and radial velocity.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
catalog.dat 135 119 *Catalog Data
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Note on catalog.dat:
NGC 2158 was dropped from Mrs. Hogg's list, because although Arp and
McCuffey (1962) have shown this to be a transitional cluster in many
respects, it is nevertheless similar in stellar content to NCG 7789
and NGC 752, which have been traditionally classified as galactic
clusters. Also dropped was the so-called ''Russian cluster'' because
under high resolution it proves to be a cluster of galaxies.
Added was a faint, sparse globular cluster at 19h30m and -30d, a plate
of which was found in Baade's files, and a globular cluster at low
latitudes, NGC 6749, pictured in Setteducati and Weaver (1962), as well
as a faint, distant cluster discovered by Arp and van den Bergh (1960).
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See also:
VII/151 : Parameters of Galactic Globular Clusters (Webbink 1985)
Byte-by-byte Description of file: catalog.dat
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Bytes Format Units Label Explanations
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1- 6 A6 --- ID *NGC number or other
7 A1 --- n_ID *[ 5] note
9- 18 A10 --- name cluster name
20- 21 I2 --- Con_Cl *?Concentration Class
22 A1 --- uConCl uncertainty indicator Concentration Class
25- 26 I2 h RAh Right Ascension hours (1950.0)
28- 31 F4.1 min RAm Right Ascension minutes (1950.0)
32 A1 --- DE- Declination sign (1950)
33- 34 I2 deg DEd Declination degrees (1950)
36- 37 I2 arcmin DEm Declination arc minutes (1950)
39- 41 I3 deg GLON Galactic Longitude l II
42 A1 --- n_GLON note to GLON
45- 47 I3 deg GLAT Galactic Lattitude b II
48- 52 F5.2 --- ABS_LAW Galactic Absorption from formula 0.24 csc b
54- 57 F4.2 mag A(B) ? Kron-Mayal case II absorption law
58- 61 F4.1 arcsec D(0.9) ?Diameter (containing 0.9 of the light)
62 A1 --- u_D(0.9) uncertainty indicator Diameter
64- 68 F5.2 mag Bmean *?Mean B mag of 25 brightest stars
70- 74 F5.2 --- Dmod ?distance modulus (m-M)app from Bmean
76 A1 --- n_Dmod *note to Dmod
78- 82 F5.1 kpc r ?galactic radius from Dmod and ABS_LAW, Fig.7
85- 89 F5.1 kpc x *?Sun centered galactic X-coordinate
92- 96 F5.1 kpc y *?galactic y-coordinate in direction rotation
99-103 F5.1 kpc z *?height above galactic plane
106-110 F5.2 mag Btot *?apparent integrated B brightness
112-115 F4.2 mag B-V ?apparent color from Kron and Mayal (1960)
117-120 F4.1 mag M(B) *?absolute magnitudes from Btot
122-125 F4.2 mag (B-V)o ?intrinsic color using E(B-V) = 0.06 csc b
127-128 A2 --- Sp spectral type from Kron and Mayal (1960)
130 A1 --- n_Sp *[ :346]note on Spectral type
132-135 I4 km/s RV ?cluster radial velocity
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Note on ID:
102 globular clusters have NGC designations
2 are listed in the Index catalogues
Note on Con_Cl:
The roman numerals have been replaced by arabic numerals.
Note on Bmean:
The apparent B magnitudes of the mean of the 25 brightest stars.
Older photographic magnitudes have all been corrected using the
photometric recalibration of the Selected Areas and the color
index correction to the B system by Arp.
Bmean can be used to estimate the distance of the cluster based
on a mean intrinsic magnitude M(B) = -0.8 mag. This is used to
derive the Dmod value.
Note on n_ID, nSp,nDmod:
Unmarked entries of Spectral Type are from Kron and Mayal (1960)
: uncertain value
1 from V(hor br), table 6 in reference
2 adjusted to RR Lyrae distance scale via figure 7 in reference
3 Spectral type from Kinman (1959b).
4 Kinman (1959b) gives F2
5 Arp-Van den Bergh
6 Kinman (1959b) gives F3
Note on Btot, M(B):
Apparent magnitudes measured by Kron and Mayal (1960) were transformed
into the Johnson V system, transformed color indices were applied to
derive Btot. Absolute magnitudes M(B) were found for the clusters that
have distances using the CSC reddening law.
Earlier measures of integrated globular cluster magnitudes by Christie
(Hogg 1959) can be compared to the Kron-Mayal measures. Transforming
both measures to the B system, it can be shown that they correlate well.
The data for 12 additional clusters based on the Christie measures
were included.
Note on x,y,z:
The coordinate system x,y, and z is centered on the Sun, with x
directed toward the galaxy center, y in the direction of the rotation,
and z perpendicular to the plane. In order to get a coordinate system
with its center at the center of the galaxy it is only necessary to
substract Ro, the distance between the Sun and the center of the
galaxy, from x.
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Other parameters:
Cluster mass. Only for 2 clusters the mass was determined based on
the internal kinematics. These are M92 (110,000 Msun) and 47 Tuc
(2.5 to 6 million Msun).
Remarks and Modifications:
Arp's Globular Cluster Catalogue has been made machine-readable by Dr.
N.P.M. Kuin at the ADC since catalog was requested frequently and the
original version submitted by Dr. G. Share only contained ID and
positions.
References:
H.C. Arp, in Galactic Structure, ed. A. Blaauw and M. Schmidt,
1965, University of Chicago Press, p. 401.
Arp, H.C. and Van den Bergh S. 1960 PASP 72, 48
Arp, H.C. and McCuffey, J. 1962 ApJ 136, 51 (1962ApJ...136...51A 1962ApJ...136...51A)
Hogg, Helen Sawyer 1959 Hdb. d. Phys., ed. S. Fluegge (Berlin:
Springer Verlag) 53, 129
Kinman T.D. 1959b MNRAS 119, 538 (1959MNRAS.119..538K 1959MNRAS.119..538K)
Kron G.E. and Mayal N.U. 1960 AJ 65, 581 (1960AJ.....65..581K 1960AJ.....65..581K)
Setteducati, A.F. and Weaver, H.F. 1962 Newly Found Star Clusters,
Vol. 1 (Berkeley, University of California, Radio Astronomy Laboratory)
(End) N.P.M. Kuin 24-Apr-1996