I/270 Catalog of Positions of IR Stellar Sources (CPIRSS) (Hindsley+ 1994)
The U.S. Naval Observatory Catalog of Positions of Infrared Stellar Sources
(Upgraded in 1996 and 2001)
Hindsley R., Harrington R., Urban S.
<Astron. J. 107, 280 (1994)>
=1994AJ....107..280H 1994AJ....107..280H
ADC_Keywords: Infrared sources ; Positional data ; Proper motions ;
Surveys ; Photometry
Description:
The U.S. Naval Observatory Catalog of Positions of Infrared Stellar
Sources (CPIRSS) was originally compiled in 1994 to provide astrometry
at the sub-arcsecond level for many of the point sources in the 1987
version of the IRAS Point Source Catalog (NASA RP-1190). This was
accomplished by the identification of IRAS sources with bright optical
stars, checked by requiring the color V-[12] (with [12] being a
magnitude derived from the IRAS flux) to be consistent with the
optical colors or spectral type. Additionally, the K magnitude (2.2
microns) has been estimated. This version, completed in 2001, contains
37,700 stars and includes the Hipparcos and Tycho-2 astrometry and
photometry which was unavailable at the time of the original
compilation.
Introduction:
The Infrared Astronomical Satellite (IRAS) carried out an all-sky
survey at 12, 25, 60 and 100 microns. Approximately 250 000 point
sources were identified. However, by the standards of optical
astrometry, the positions of these sources are poorly determined, with
errors of tens of arc-seconds. Optical astrometric catalogs such as
Hipparcos (ESA 1997) and Tycho-2 (Hoeg et al. 2000) have errors in
position under 0.1 arc-seconds, some two to three orders of magnitude
less than the IRAS positions.
Many of the sources in the IRAS Point Source Catalog (1987, hereafter
referred to as PSC) have been identified as stars. Thus it is possible
to construct a higher quality astrometric catalog of infrared sources
by combining these positions with the IRAS identifications. However,
because the IRAS positions have such large errors, the identifications
provided in the PSC are suspect. The V-[12] color, with [12] being a
magnitude determined from the 12 micron flux, is very sensitive to
temperature. If the optical identification of an IRAS source is
correct, the V-[12] color should be consistent with optical colors or
spectral type. Once a cross-correlation is established, an estimation
of the Johnson system K magnitudes is made. Hindsley and Harrington
(1994) describe the details on the confirmation identification based
on color and the K magnitude determination.
The CPIRSS has had two upgrades following the 1994 release; one in
1996 and one in 2001. In 1996, 4022 new sources were added, bringing
the total to 37,700. As with the 33,678 stars in the original CPIRSS,
the positional matches were checked by using the optical colors and
visual magnitudes to estimate the 12 micron magnitudes, which were
compared to the actual IRAS 12 micron measurement. Stars with an
estimate that do not match the observations are included in the
catalog but flagged so that the user is aware of the questionable
identification. Also in 1996, the record number in the IRAS Point
Source Catalog was added to each record. The 1996 version also had
various errata corrected.
In 2001, better astrometry was substituted. Of the 37,700 stars, all
but 105 were found in either the Hipparcos or Tycho-2 catalogs (Cat.
I/246, I/259). Since these surpass the accuracies found in the
astrometric catalogs used in earlier versions, their values were
added. Given the availability of both for a star, the Hipparcos data
take precedence. Both Hipparcos and Tycho-2 numbers are provided,
along with several flags that can give users warning of possible
multiplicity or non-linear proper motions. At the same time, the V
magnitudes from Hipparcos or Tycho-2 were substituted for the poorer
values found in the previously used astrometric catalogs. Since much
of the original work was performed using those older values,
differences between them and the current values are provided for the
user.
Earlier versions of this work were not put into the Astronomical Data
Centers, but were made available through the U.S. Naval Observatory.
File Summary:
------------------------------------------------------------------------------
FileName Lrecl Records Explanations
------------------------------------------------------------------------------
ReadMe 80 . This file
cpirss01.dat 256 37700 The CPIRSS (2001) catalog
------------------------------------------------------------------------------
See also:
II/125 : IRAS catalogue of Point Sources, Version 2.0 (IPAC 1986)
V/98 : MSX Infrared Astrometric Catalog (Egan+ 1996)
Byte-by-byte Description of file: cpirss01.dat
------------------------------------------------------------------------------
Bytes Format Units Label Explanations
------------------------------------------------------------------------------
001-010 A10 --- DM_ID Primary Durchmusterung identifier
012-022 A11 --- IRAS IRAS PSC (Cat. II/125) identifier
024-029 I6 --- PSCrec IRAS PSC (Cat. II/125) record number
031-032 I2 h RAh R.A. (hours), epoch=2000.0, ICRS
033-034 I2 min RAm R.A. (minutes), epoch=2000.0, ICRS
035-040 F6.3 s RAs R.A. (seconds), epoch=2000.0, ICRS
042-048 F7.3 10ms/yr pmRA Proper motion in RA, seconds/century
050-050 A1 --- DE- Decl. (sign), epoch=2000.0, ICRS
051-052 I2 deg DEd Decl. (degrees), epoch=2000.0, ICRS
053-054 I2 arcmin DEm Decl. (minutes), epoch=2000.0, ICRS
055-059 F5.2 arcsec DEs Decl. (seconds), epoch=2000.0, ICRS
061-067 F7.2 10mas/yr pmDE Proper motion in Decl., arcsec/century
069-070 I2 --- r_RAh *Source of position
072-080 E9.4 Jy Fnu_12 IRAS flux density, 12 micron
081-089 E9.4 Jy Fnu_25 IRAS flux density, 25 micron
090-098 E9.4 Jy Fnu_60 IRAS flux density, 60 micron
099-107 E9.4 Jy Fnu_100 IRAS flux density, 100 micron
109-114 F6.3 mag Vmag *?Observed V magnitude
116-121 F6.3 mag Vdiff *Vmag(previous) - Vmag(cpirss2001)
123-123 I1 --- r_Vmag *Source of V magnitude
125-139 A15 --- SpType *Spectral type
140-141 I2 --- r_SpType *?Source of Spectral Type
143-148 F6.3 mag Color *?Color
150-150 A1 --- f_Color *Flag for color
152-157 F6.3 mag Excess *?B-V color excess
159-159 I1 --- Method *Method used in color confirmation
161-166 F6.2 mag Deviat *Color deviation
168-168 I1 --- Confrm *Result of color confirmation
170-175 F6.3 mag Kmag ?Estimated K magnitude
177-177 I1 --- Qual_12 *IRAS Flux quality indicator; 12 microns
178-178 I1 --- Qual_25 *IRAS Flux quality indicator; 25 microns
179-179 I1 --- Qual_60 *IRAS Flux quality indicator; 60 microns
180-180 I1 --- Qual_100 *IRAS Flux quality indicator; 100 microns
182-182 A1 --- Corr_12 *IRAS correlation coeff.; 12 microns
183-183 A1 --- Corr_25 *IRAS correlation coeff.; 25 microns
184-184 A1 --- Corr_60 *IRAS correlation coeff.; 60 microns
185-185 A1 --- Corr_100 *IRAS correlation coeff.; 100 microns
187-188 I2 % Vari *Probability (0%-99%) of variability
190-196 A7 --- WDS *WDS id code (discoverer & number)
197-201 A5 --- m_WDS *WDS components
203-206 I4 yr WDS_yr ?Year of last observation in WDS
208-210 I3 deg WDS_theta ?Position angle at last obs. in WDS
212-216 F5.1 arcsec WDS_rho ?Separation at last obs. in WDS
218-222 F5.2 mag WDS_mag1 ?V magnitude of primary in WDS
224-228 F5.2 mag WDS_mag2 ?V magnitude of secondary in WDS
230-230 A1 --- WDS_orb *[O] Orbit flag
231-236 I6 --- HIP ?Hipparcos number
237-237 A1 --- H10 *HIP field 10; double and mult. system
238-238 A1 --- H59 *HIP field 59; annex flag
239-250 A12 --- TYC2 *?Tycho-2 number
251-251 A1 --- T10 *Tycho-1 field 10; Ref. for astrometry
252-252 I1 --- T40 *?Tycho-1 field 40; Astrometric Quality
253-253 A1 --- T49 *?Tycho-1 field 49; Duplicity from Tycho-1
254-254 A1 --- Tpflag *?Tycho-2 position flag
255-255 A1 --- Tposflg *?Tycho-2 posflg, astrometric treatment
256-256 I1 --- dupflg *?CPIRSS duplicity flag
--------------------------------------------------------------------------------
Note on r_RAh:
This field is the source of astrometry.
4 = Astrographic Catalogue Reference Stars (ACRS, Cat. I/171)
6 = Positions and Proper Motions Catalog (PPM, Cat. I/146 I/193)
7 = Smithsonian Astrophysical Observatory Star Catalog (SAO, Cat. I/131)
10 = Hipparcos, Cat. I/239
11 = Tycho-2, Cat. I/259
Note on Vmag and Vdiff:
These fields give the current, best values for Vmag, as well as
information regarding these parameters in previous releases of the
CPIRSS. It was decided to provide the best V magnitude available, so
many values have been replaced from earlier releases. When the Vmag
data are from Hipparcos, the values from Hipparcos H5 field were used.
Where the Vmag data are from Tycho-2, the values from VT were used
with no conversion to the Johnson system attempted. Since the color
confirmation and K magnitude estimates were made using older data, it
was decided to provide users a way to compute these older values. The
field Vdiff is the value of the older Vmag - current Vmag. Large
values of Vdiff often indicate no Vmag was given in the earlier
versions of the catalog.
Note on r_Vmag:
This field it the source of the observed V magnitude
1 = Mermilliod 1991, Cat. II/168
2 = Lanz 1986A&AS...65..195L 1986A&AS...65..195L, Cat. II/116
8 = From Astrographic Catalogue Reference Stars, Cat. I/171
9 = From the same catalog as the positional information
Data NOT from Mermilliod 1991, Lanz 1986, Hipparcos or Tycho-2 is
deemed somewhat unreliable.
Note on SpType and r_SpType:
These fields are for the spectral type and its source
For r_SpType,
1 = MK Extension catalog (Morris-Kennedy 1983, Cat. III/78)
2 = Michigan HD catalog (Houk & Cowley 1975-88,
Cat. III/31, III/51, III/80, III/133)
3 = Henry Draper catalog (Cannon & Pickering 1918-24, Cat. III/135)
4 = Average of MK Ext. data(1) and Michigan HD data(2)
Positive values of the source mean the raw entries have been
"interpreted" (eg, a spectral subtype of 3+ in the MK Extension
catalog has been converted into 3.5). A negative source value means
that the data are directly from the catalog. Note that the result of
averaging two catalogs' data (source = 4) is occasionally a subclass
not represented in either catalog. For example, K5 & M0 are averaged
to produce K7.5, although neither the MK Extension catalog nor the
Michigan HD catalog have any spectral subtypes between K5 and M0. The
spectral types are used for determining intrinsic colors, and the
fictitious subtype K7.5 is useful for interpolating. Also note that
the result of averaging luminosity classes can be intermediate between
two classes. This is indicated by a value in bytes 135:137 (eg, .5,
.75). Such a value as 'IV .25' should be interpreted as being 0.25 of
the way from luminosity class IV toward V. Again the point is to allow
interpolation, in this case for calculating absolute magnitudes.
Note on Color, f_Color:
The field f_Color is the flag for the color field.
'1'= Intrinsic (not reddened) B-V
'2'= Observed (reddened) B-V
'3'= Observed (reddened) R-I
Note on Excess:
This field is the B-V color excess. Its interpretation depends on
field 'Method' (byte 159). If byte 159 is 1, this was calculated as
the difference (observed color - intrinsic color). Otherwise this was
calculated from the coordinates and the relationships of Arenou,
Grenon, and Gomez (1992A&A...258..104A 1992A&A...258..104A). Blank means assumed zero if
byte 159 is 1, 2, 3, 4, or 5; otherwise, blank means it cannot be
estimated.
Note on Method:
This field indicates the method used in color confirmation
0 = insufficient data available, no color confirmation attempted
1 = both B-V and spectral type available
2 = only spectral type (with luminosity class) available
3 = only spectral type (without luminosity class) available
4 = B-V only available (no spectral type)
5 = R-I used; either no B-V data at all, or not both B-V and spectral type
data (case 1 above). R-I used in this case if available because
it is less sensitive to reddening.
Note on Deviat:
If this value is lower than 20.0, then this is the deviation
([calculated from color confirmation] - [observed from IRAS])
in magnitudes. For values greater than 20.0, the color confirmation
could not be attempted and the value indicates what data are lacking,
with the following meaning.
21.0 = IRAS 12 micron flux is a lower limit
22.0 = IRAS variability probability > 50%
23.0 = Color data indicates multiplicity
24.0 = Color data indicates variability
25.0 = Spectral type data indicates multiplicity
26.0 = Spectral type data indicates variability
27.0 = Spectral type data indicates peculiarity
(eg, Carbon star, Am star, emission or peculiar)
28.0 = No observed V magnitude
29.0 = No observed color or spectral type data
30.0 = Color too red: (B-V) > 1.60, cannot analyze
31.0 = Reddening < -0.15; indicates spectral type data
or photometry is in error (probably one data set does not apply
to this star or is contaminated by a double).
Note on Confrm:
This field shows the results of the color confirmation.
0 = No color confirmation attempted
1 = Optical and IRAS match confirmed
2 = Optical and IRAS match questionable
Note on Qual_12, Qual_25, Qual_60, Qual_100:
These fields are the IRAS Flux quality indicators.
1 = Upper limit
2 = Moderate quality
3 = High quality
Note on Corr_12, Corr_25, Corr_60, Corr_100:
These fields are the IRAS point source correlation coefficients.
A =100%, B =99%, etc. See IRAS Point Source Catalog, col. 14.
Note on Vari:
This field indicates the percent probability of variability.
A value of -1 means the source was not examined for variability.
Note on WDS:
This field gives discoverer designation and number from the
Washington Double Star catalog (WDS; Worley and Douglass 1984, Cat. I/107).
Note on m_WDS:
This field gives data on the components. AB means data for components
A and B. A-BC means secondary component consists of a double. Etc.
Note on WDS_orb:
This field indicates an orbit is available in the WDS catalog.
'O' = Orbit available
' ' = No orbit available
Note on H10:
This field is the Hipparcos field 10, reference flag for astrometry
A,B,... = The specified component of multiple system.
@ = Photocenter of multiple system. See HIP-C annex.
+ = Center of mass. See HIP-O annex.
Note on H59:
This field is the Hipparcos field 59, double/multiple system flag.
C = Component solutions available from Hipparcos
G = acceleration terms available from Hipparcos
O = Orbital solutions available from Hipparcos
V = variability induced mover from Hipparcos
Note on TYC2:
This field gives the Tycho-2 identification number (3 numbers separated
by a dash). Note that if the star was in Tycho-1 but not Tycho-2, the
Tycho-1 ID is given.
Note on T10:
This field is the Tycho-1 field 10, reference flag for Tycho-1 astrometry
'X' = Indication of a dubious astrometric reference star.
Note on T40:
This field is the Tycho-1 field 40, astrometric quality flag
' ' = HIP star not observed by Tycho.
1 to 4 = very high to high quality.
5 = medium quality.
6 = perhaps non-single.
7 = low quality.
8 = perhaps non-stellar.
9 = low quality; position derived from TICR.
Note on T49:
This field is the Tycho-1 filed 49, duplicity flag.
' ' = HIP star not observed by Tycho.
'D' = Duplicity clearly indicated.
'R' = duplicity weakly indicated.
'S' = duplicity suspected.
'Y' = investigation made; no indication of duplicity found.
'Z' = investigation for duplicity not made.
Note on Tpflag:
This field is the Tycho-2 pflag, it has the following meaning.
' ' = normal mean position and proper motion
'P' = astrometry from photocenter of two Tycho-2 stars
'X' = no mean position, proper motion in Tycho-2
Note on Tposflg:
This field is the Tycho-2 posflg, and describes what treatment method the
Tycho-2 data utilized to get position.
' ' = normal treatment in Tycho-2
'D' = double star treatment
'P' = photocenter treatment
Note on dupflg:
This field is an attempt to summarize many of the WDS, Hipparcos,
Tycho-1 and Tycho-2 flags found above into one flag.
' ' = astrometry does not indicate duplicity
'1' = astrometry does indicate duplicity
--------------------------------------------------------------------------------
References:
A tridimensional model of the galactic interstellar extinction, 1992,
Arenou, F., Grenon, M., and Gomez, A., Astron & Astrophys., 258, 104.
=1992A&A...258..104A 1992A&A...258..104A
The Henry Draper Catalog, 1918-1924, Cannon, A.J., & Pickering, E.C.,
Ann. Astron. Obs. Harvard College, 91-99 (from CDROM)
University of Michigan Catalogue of Two-Dimensional Spectral Types for the
HD Stars, vol. 1, 1975, Houk, N. and Cowley, A.P., (this and vol. 2, 3,
and 4 from CDROM).
IRAS Catalogues and Atlases: The Explanatory Supplement, 1987, eds. C.A.
Beichman, G. Neugebauer, H.J. Habing, P.E. Clegg, T.J. Chester,
NASA RP-1190, vol. 1.
IRAS Catalogues and Atlases: The Point Source Catalog, 1987, eds. C.A.
Beichman, G. Neugebauer, H.J. Habing, P.E. Clegg, T.J. Chester,
NASA RP-1190, vol. 2-6 (from CDROM).
Photoelectric Photometric Catalogue in the Johnson UBVRI System, 1986,
Lanz, T., A&A Suppl., 6, 195 (from CDROM),
=1986A&AS...65..195L 1986A&AS...65..195L
Homogeneous Means in the UBV System, 1991, Mermilliod, J.-C.,
unpublished (from CDROM)
MK Classification System, 1983, Morris-Kennedy, P.,
unpublished (from CDROM)
Selected Astronomical Catalogs, 1991, vol. 1, No. 1,(USANASAADCCAT0011),
Astronomical Data Center, Goddard Space Flight Center, NASA (CDROM).
Superseded Washington Double Star Catalog, 1984, Worley, C.E., and Douglass,
G.G., unpublished (from CDROM).
The U.S. Naval Observatory Catalog of Positions of Infrared Stellar
Sources, 1994, Hindsley R. and Harrington R., Astron. Journal,107, 280,
=1994AJ....107..280H 1994AJ....107..280H
The Hipparcos and Tycho Catalogues, 1997, ESA SP-1200,
=1997HIP...C......0E 1997HIP...C......0E
The Tycho-2 Catalogue of the 2.5 Million Brightest Stars, Hog E.,
Fabricius C., Makarov V.V., Urban S., Corbin T., Wycoff G., Bastian U.,
Schwekendiek P., Wicenec A., Astron. Astrophys. 355, 27 (2000),
=2000A&A...355L..27H 2000A&A...355L..27H
(End) S. Urban [U.S. Naval Observatory], T. Sodroski [SSDOO/ADC] 27-Mar-2001