J/A+A/402/801 Runaway carbon stars of Blanco & McCarthy field 37 (Loup+, 2003)
On the usefulness of finding charts.
Or the runaway carbon stars of the Blanco & McCarthy field 37.
Loup C., Delmotte N., Egret D., Cioni M.-R., Genova F.
<Astron. Astrophys., 402, 801-804 (2003)>
=2003A&A...402..801L 2003A&A...402..801L
ADC_Keywords: Surveys ; Stars, carbon ; Magellanic Clouds ;
Cross identifications
Keywords: errata - catalogs - surveys - stars: carbon - Magellanic Clouds
Abstract:
We have been recently faced with the problem of cross-identifying
stars recorded in historical catalogues with those extracted from
recent fully digitized surveys (such as DENIS and 2MASS). Positions
mentioned in the old catalogues are frequently of poor precision, but
are generally accompanied by finding charts where the interesting
objects are flagged. Those finding charts are sometimes our only link
with the accumulated knowledge of past literature. While checking the
identification of some of these objects in several catalogues, we had
the surprise to discover a number of discrepancies in recent works.The
main reason for these discrepancies was generally the blind
application of the smallest difference in position as the criterion to
identify sources from one historical catalogue to those in more recent
surveys. In this paper we give examples of such mis-identifications,
and show how we were able to find and correct them.We present modern
procedures to discover and solve cross-identification problems, such
as loading digitized images of the sky through the Aladin service at
CDS, and overlaying entries from historical catalogues and modern
surveys. We conclude that the use of good finding charts still remains
the ultimate (though time-consuming) tool to ascertain
cross-identifications in difficult cases.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 34 48 Cross-identification counts
table2.dat 87 849 List of cross-identifications between the
Blanco & McCarthy (1990AJ....100..674B 1990AJ....100..674B),
Kontizas et al. (2001, J/A+A/369/932), and
DCMC (Cioni et al., 2000, II/228), catalogues
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See also:
II/228 : DENIS Catalogue toward Magellanic Clouds (DCMC) (Cioni+ 2000)
J/A+A/369/932 : RI photometry of LMC carbon stars (Kontizas+, 2001)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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3- 4 I2 --- Field LMC-BM field number (1990AJ....100..674B 1990AJ....100..674B)
9- 10 I2 --- NC* Number of BM C stars (All = 849)
15- 16 I2 --- NKDM Number cross-identified with KDM , Kontizas
et al., 2001, Cat. J/A+A/369/932)
using finding charts (All = 586)
21- 22 I2 --- NKDM3 Number cross-identified in KDM Table 3
(All = 527)
27- 28 I2 --- Nwci Number of wrong cross-identifications in KDM
(All = 23)
33- 34 I2 --- Nmci Number of missed cross-identifications in KDM
(All = 67)
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 5 A5 --- LMC-BM LMC-BM number (fieldnumber-sourcenumber)
7- 10 I4 --- KDMK Actual [KDM2001] number: cross-identifications
based on finding charts
12- 16 F5.1 arcsec Dist Distance between LMC-BM and [KDM2001] positions
18- 21 I4 --- KDMK2 ?=0 [KDM2001] number based on an automatic
match with a radius of 30"
23- 27 F5.1 arcsec Dist2 Distance between LMC-BM and [KDM2001]2 positions
29- 32 I4 --- KDMK3 ?=0 [KDM2001] number based on an automatic
match with a radius of 1'
34- 38 F5.1 arcsec Dist3 Distance between LMC-BM and [KDM2001]3 positions
40- 43 I4 --- KDMK4 ?=0 [KDM2001] number according to
Kontizas et al. (J/A+A/369/932) Table 3
45- 49 F5.1 arcsec Dist4 Distance between LMC-BM and [KDM2001]4 positions
51- 68 A18 --- DCMC DCMC J identification (HHMMSS.ss+DDMMSS.s):
cross-identifications based on finding charts
70- 87 A18 --- DCMC2 Double entries in the DCMC catalogue
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Acknowledgements:
Cecile Loup, loup(at)astro.u-strasbg.fr
(End) Patricia Vannier [CDS] 29-Jul-2008