J/AJ/120/2496 Spaghetti Survey (Dohm-Palmer+ 2000)
Washington Stellar Photometry for the Spaghetti Survey
Dohm-Palmer R., Mateo M., Olszewski E., Morrison H., Harding P.,
Freeman K., Norris N.
<Astron. J., 120, 2496 (2000)>
=2000AJ....120.2496D 2000AJ....120.2496D
ADC_Keywords: Milky Way; Photometry; Stars, halo
Keywords: Galaxy: evolution - Galaxy: formation - Galaxy: halo -
Galaxy: stellar content
Description:
The Spaghetti project is a pencil-beam photometric and spectroscopic
survey designed to identify structure in the Galactic halo. Four-color
stellar photometry in the modified Washington filter set is used to
identify halo stars for spectroscopic observations. The filters include
C, M, T2 and DDO51. The fields in the survey are chosen from high
Galactic-latitude positions with low reddening and no stars as bright as
SAO stars. Thus far we have imaged 134 fields covering a total area of
52deg2. These fields are listed in table1.dat. Due to weather, the
only fully calibrated photometry was measured from images taken with the
BTC ccd mosaic camera on the CTIO 4m telescope in April 1999. Table4.dat
lists these stars from the 53 BTC fields, which covers a total area of
13 square degrees. These data include only those stars whose measurement
errors are less than 0.04 in all four filters (32655 total stars).
Photometric measurements of stars in the other fields will be published
as soon as they can be fully calibrated.
See GCPD/48 for a short description of the Washington Photometric
system.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 84 134 Observed Fields
table4.dat 101 32655 Astrometry and Photometry
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See also:
2000AJ....119.2254M 2000AJ....119.2254M : Mapping the Galactic Halo. I. The ``Spaghetti'' Survey
http://www.astro.lsa.umich.edu/users/rdpalmer/spag : Home page for
spaghetti project
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- Name Field name
12- 16 F5.1 deg GLON Galactic longitude
18- 22 F5.1 deg GLAT Galactic latitude
24- 25 I2 h RAh Right Ascension (J2000)
27- 28 I2 min RAm Right Ascension (J2000)
30- 34 F5.2 s RAs Right Ascension (J2000)
36 A1 --- DE- Declination (J2000)
37- 38 I2 deg DEd Declination (J2000)
40- 41 I2 arcmin DEm Declination (J2000)
43- 46 F4.1 arcsec DEs Declination (J2000)
48- 52 F5.3 mag E(B-V) Reddening
54- 55 I2 "month" Date.M *? Month observation was taken (UT)
57- 58 I2 --- f_Date.M *? Indicates a range in months
60- 61 I2 d Date.D ? Day observation was taken (UT)
63- 66 I4 yr Date.Y Year observation was taken (UT)
68- 77 A10 --- Inst *Instrument used in observation
79- 84 A6 --- Cond *Observation conditions
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Note on Date.M and f_Date.M: Form the range over which observations were taken.
Note on Inst: The data for each field observed with the Schmidt were obtained
over several nights in October or November of 1998.
BTC = BTC camera mounted on the CTIO 4m.
Mosaic-N = the Northern Mosaic camera mounted on the KPNO 4m.
Mosaic-S = the Southern Mosaic camera mounted on the CTIO 4m.
B. Schmidt = the Burrell Schmidt at KPNO, owned and operated by Case
Western Reserve University.
Note on Cond: Unless otherwise noted, conditions were photometric.
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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- 8 F8.4 deg GLON Galactic longitude
10- 17 F8.4 deg GLAT Galactic latitude
19- 20 I2 h RAh Right Ascension (J2000)
22- 23 I2 min RAm Right Ascension (J2000)
25- 29 F5.2 s RAs Right Ascension (J2000)
31 A1 --- DE- Declination sign
32- 33 I2 deg DEd Declination (J2000)
35- 36 I2 arcmin DEm Declination (J2000)
38- 41 F4.1 arcsec DEs Declination (J2000)
43- 43 I1 --- Chip *BTC chip number
45- 50 F6.3 mag Mmag M band magnitude (around 500nm,
Canterna 1976AJ.....81..228C 1976AJ.....81..228C)
52- 56 F5.3 mag e_Mmag Uncertainty in M
58- 63 F6.3 mag (M-T2) M-T2 color (Canterna 1976AJ.....81..228C 1976AJ.....81..228C)
65- 69 F5.3 mag e_(M-T2) Uncertainty in (M-T2)
71- 76 F6.3 mag (M-51) ? M-DDO51 color (Canterna
1976AJ.....81..228C 1976AJ.....81..228C;
Geisler 1984PASP...96..723G 1984PASP...96..723G)
78- 82 F5.3 mag e_(M-51) ? Uncertainty in (M-51)
84- 89 F6.3 mag (C-M) ? C-M color (Canterna 1976AJ.....81..228C 1976AJ.....81..228C)
91- 95 F5.3 mag e_(C-M) ? Uncertainty in (C-M)
97-101 F5.3 mag E(B-V) *Reddenning parameter
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Note on Chip:
It was discovered that chips 1 and 2 had been switched in the
electronics during these observations. For internal consistency we report
the chip number as recorded in our data. Thus, chip 1 here actually
refers to the BTC chip traditionally labeled 2, while chip 2 in these data
actually refers to the BTC chip traditionally labeled 1.
Note on E(B-V):
The reddening parameter for each star was determined from
the reddening maps of Schlegel, Finkbeiner, & Davis (SFD)
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References:
Schlegel D.J., Finkbeiner D.P., & Davis M. 1998, ApJ, 500, 525
=1998ApJ...500..525S 1998ApJ...500..525S
Geisler D. 1984, PASP, 96, 723 =1984PASP...96..723G 1984PASP...96..723G
Canterna, R. 1976, AJ, 81, 228 =1976AJ.....81..228C 1976AJ.....81..228C
(End) Robbie Dohm-Palmer [University of Michigan] 28-Jul-2000