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II/59B Catalogue of stellar UV fluxes (TD1) (Thompson+ 1978)
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Catalogue of stellar ultraviolet fluxes (TD1):
A compilation of absolute stellar fluxes measured by the Sky Survey
Telescope (S2/68) aboard the ESRO satellite TD-1
Thompson G.I., Nandy K., Jamar C., Monfils A., Houziaux L.,
Carnochan D.J., Wilson R.
<The Science Research Council, U.K. (1978)>
=1978QB6.C389.......
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ADC_Keywords: Photometry, ultraviolet
Mission_Name: TD1
Description (adapted from ADC documentation EAC-T-5294-0028):
The Belgian/UK Ultraviolet Sky Survey Telescope (S2/68) in the ESRO
TD1 satellite carried out a controlled scan of the whole sky. It
measured the absolute ultraviolet flux distribution between 2740A
(274nm) and 1350A (135nm) of point sources down to tenth visual
magnitude for unreddened early B stars. The S2/68 experiment has been
described by Boksenberg et al. (=1973MNRAS.163..291B) and the absolute
calibration by Humphries et al. (=1976A&A....49..389H).
The catalog contains results from the sky-scan experiment in the TD1
satellite of the European Space Research Organization. The catalog
lists the absolute ultraviolet fluxes in four passbands:
---------------------------------------------------------
Passband Center: 274.0nm 236.5nm 196.5nm 156.5nm
Effective Width: 31.0 33.0 33.0 33.0
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for 31215 stars. The stars have been selected subject to the
constraint that the signal-to-noise ratio should be at least 10.0 in
any one of the four passbands.
Many of the fainter stars of spectral types later than A5 do not have
significant signals in all of the spectrophotometric channels
(particularly the 1565A channel). Consequently, after the removal of
the background, they can randomly give rise to small negative values
of flux. We have decided not to suppress these negative values but to
give them together with their error as they can be significant when
considered as part of a statistical sample.
Although the sky coverage is essentially complete, the catalogue does
not contain the fluxes for all stars that fall within the limit of the
sensitivity of the instrument. If any star expected to be present is
missing, then its signal is probably blended with that of a nearby
star in which case the data have been discarded.
The fluxes F(lambda), and errors, sigma(lambda),
can be transformed to the visual magnitude scale using the absolute
calibration of Haynes & Latham (=1975ApJ...197..593H):
m(lambda) = -2.5 log10 F(lambda) - 21.175
sigma_m(lambda) = 1.086 sigma(lambda)/F(lambda)
Also:
F(nu) = 3.336x10^-19^ lambda^2 F(lambda)
m(nu) = -2.5 log10 F(lambda) - 5 log10 lambda - 18.724
sigma_m(nu) = 1.086 sigma(lambda)/F(lambda)
where F(lambda) is in units of erg.cm^-2^.s^-1^.A^-1^ (mW/m2/(0.1nm))
lambda is in Angstroms and
F(nu) is in units of erg.cm^-2^.s^-1^.Hz^-1^
(mW/m2/Hz = 10^23^Jy)
See also:
III/39 : Ultraviolet Bright Stars Spectrophotometric CATalogue
from TD1 (Jamar+ 1976)
II/86 : Supplement to the UVBS Photometric Catalogue
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
catalog 106 31215 The Catalog of Stellar UV Fluxes
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Byte-by-byte Description of file: catalog
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Bytes Format Units Label Explanations
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1- 5 I5 --- TD1 [1/31215]+ Catalog running number
7- 12 I6 --- HD [1/359083]?=0 Henry Draper Catalog number
14 I1 --- UVBSflag [0/1] '1' if in UVBS Catalog
(Jamar et al. 1976) (=III/39A)
15- 24 A10 --- DM Durchmusterung (BD/CD/CPD) designation, as
CCsZZNNNNN (catalog, sign, zone number)
25- 30 I6 --- S2/68 [1/58012] S2/68 Catalog Number
32- 35 F4.1 mag Vmag Visual magnitude
37- 39 A3 --- SpType Spectral type
41- 48 F8.6 rad RArad Right ascension, 1950.0, in radians
50- 58 F9.6 rad DErad Declination, 1950.0, in radians
59- 64 F6.2 10mW/m2/nm F2740 []?=-10.00 Flux in 2740A band (see Exp)
65- 69 F5.2 10mW/m2/nm e_F2740 []?=-1.00 Standard error for F2740 (see Exp)
70- 75 F6.2 10mW/m2/nm F2365 []?=-10.00 Flux in 2365A band (see Exp)
76- 80 F5.2 10mW/m2/nm e_F2365 []?=-1.00 Standard error for F2365
(see Exp) (1)
81- 86 F6.2 10mW/m2/nm F1965 []?=-10.00 Flux in 1965A band (see Exp)
87- 91 F5.2 10mW/m2/nm e_F1965 []?=-1.00 Standard error for F1965
(see Exp) (1)
92- 97 F6.2 10mW/m2/nm F1565 []?=-10.00 Flux in 1565A band (see Exp)
98-102 F5.2 10mW/m2/nm e_F1565 []?=-1.00 Standard error for F1565 (see Exp)
103-106 I4 --- Exp [-12/-9] 10-base exponent for all Fluxes,
e.g. Flux(2740) = 10^Exp^ x F2740
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Note (1): a few records with standard errors in F2365 and F1965 larger
than 100.00 were assigned a value of '99.99'. This occured in
records (TD1 numbers):
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TD1 HD Band Error
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639 6676 1965 133.70
14977 91979 1965 110.22
17270 123445 1965 114.56
18199 137058 2365 119.69
18199 137058 1965 213.83
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In reference to these specific figures, G. I. Thompson remarks in a
private communication: "...the formal computed error has turned out to
be so large that the result is probably worthless anyway."
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See also:
III/39 : UV Bright Star Spectrophotometric Catalog (Jamar et al., 1976)
II/86 : Supplement to the UVBS Photometric Catalogue
References:
Boksenberg A., Evans R.G., Fowler R.G., Gardner I.S.K., Houziaux L.,
Humphries C.M., Jamar C., Macau D., Malaise D., Monfils A., Nandy K.,
Thompson G.I., Wilson R., Wroe H., =1973MNRAS.163..291B
Haynes D.S., Latham D.W., =1975ApJ...197..593H
Humphries C.M., Jamar C., Malaise D., Wroe H., =1976A&A....49..389H
Jamar C., Macau-Hercot D., Monfils A., Thompson G.I., Houziaux L.,
Wilson R., 1976, "Ultraviolet Bright Star Spectrophotometric
Catalogue", ESA Special Report 27 (Cat. <III/39>)
Thompson G.I., Nandy K., Jamar C., Monfils A., Houziaux L., Carnochan A.,
Wilson R., =1979BICDS..17...78T
Historical Notes:
* from ADC Documentation (EAC-T-5294-0028) by Robert S. Hill and
Theresa A. Nagy (1981), revised April 1991 by Susan E. Gessner
and Lee E. Brotzman, NASA/GSFC:
The "Catalogue of Stellar Ultraviolet Fluxes", which represents
results from the sky-scan experiment in the TD1 satellite of the
European Space Research Organization (ESRO), was received from Dr. G.
I. Thompson of the Royal Observatory, Edinburgh, Scotland. The present
documentation is mostly a rearrangement of material provided by Dr.
Thompson.
The tape as received was edited at GSFC as follows: five
standard-error values represented by asterisk-filled fields were
changed to 99.99. The actual values as given in the hard copy version
of the catalogue are given in the "Byte-by-Byte description" above.
Some of the pertinent statistics for the data on this tape have been
determined. The number of entries which have no valid data for the
star as a function of wavelength are:
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Lamda (A) Entries
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2740 5
2365 752
1965 747
1565 735
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and, the number of entries that have small negative flux values as a
function of wavelength are:
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Lamda (A) Entries
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2740 8
2365 97
1965 154
1565 3392
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The catalog was again revised in April 1991. Two byte catalog
designations were added to the Durchmusterung numbers. During this
process, Dr. Nancy Roman discovered that several of the values given
in the original catalogue for the right ascension field (bytes 40-48)
were in error. These values were corrected by subtracting 0.0043633
from the original value. The records in which this change occured are:
8703 9546 21996
9322 9671 31105
9509 10112 31139
9414 21723
* October 1991: "Selected Astronomical Catalogs" Vol. 1 CD-ROM, directory
/photom/td1
* 24-Oct-1995: Documentation file added at CDS (F. Ochsenbein, J. Florsch)
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(End) Francois Ochsenbein [CDS] 24-Oct-1995