MISAO Project

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Here describes how to identify each star detected by the PIXY system with known variable stars. You have to examine the image by the PIXY system and create a PXF file in advance. And you also have to construct the identification database in advance, following the steps described in the Identification Database Construction.

o Execution

Identification with known variable stars is run by -identify option of the PIXY system, with a name of PXF file created by the PIXY system. You must set the property misao.home as the MISAO home directory's path, using -D option of java command.

For example, let's identify the result of the sample image in the Tutorial. The PXF file is sample.pxf. Here let's see the MISAO home directory as C:\misao. Now type as follows and run the identification.

java   -Dmisao.home=C:\misao   misao.pixy.Pixy   -identify   sample.pxf

The result of identification is written over the same PXF file. On the display, the list of identified stars with positional difference and the list of double-identified stars are output for verification of the result. When setting the name of check file after name of PXF file, the verification result is also saved in the check file. The extension of check file is .icl.

java   -Dmisao.home=C:\misao   misao.pixy.Pixy   -identify   sample.pxf   sample.icl

o Result

Here is the identification result of the sample image.


In the data of stars identified with known variable stars, the name of variable stars and the data in the database are recorded.

Before identification
D| 11 48 14.71 +48 31 25.3  mag= 7.53  x= 288.60  y= 280.24
C| GSC3452.1191  11 48 14.69  +48 31 25.7   8.03
M| O-C(Mag)=-0.50 mag
After identification
S=IRAS 11455+4848
D| 11 48 14.71 +48 31 25.3  mag= 7.53  x= 288.60  y= 280.24
C| GSC3452.1191  11 48 14.69  +48 31 25.7   8.03
R| HT UMA  R.A.=11 48 14.70  Decl.=+48 31 25.6  8.275 - 8.39
1 mag (Hp)  Sp:M2III
R| IRAS 11455+4848  R.A.=11 48 13.26  Decl.=+48 31 32.4  (33
x 3", p.a.=122)  flux(12)=1.65  flux(25)=0.43  flux(60)=<0.4
0  flux(100)=<1.00  5% variable
M| O-C(Mag)=-0.50 mag

* Some lines are forced to be folded here.

This star is classified as RM, a candidate of variable stars, by the PIXY system. After identification, the system makes it clear as a known variable star:

HT UMa = IRAS 11455+4848

The name of identified variable star is expressed in the syntax "type=name". Please read the Object types in identification database for more details about the type.

At the end of the PXF file, the data of variable stars which are in the image area but were not detected are recorded as NR. The position (x,y) is also recorded.

S=IRAS 11469+4842
D| x= 267.59  y= 187.12
R| IRAS 11469+4842  R.A.=11 49 37.48  Decl.=+48 25 44.0  (55
x 15", p.a.=124)  flux(12)=<0.25  flux(25)=<0.25  flux(60)=0
.45  flux(100)=1.47

* Some lines are forced to be folded here.

You can stop recording data of such non-detected stars by setting -noNR option after -identify option.

o Verification of result

On the display, and into the check file, the list of identified stars with positional difference and the list of double-identified stars are output for verification of the result.

[Identification Check List]
HT UMA                  RM-00004        0.3"            0.1"  

The name of a variable star, the star's ID named by the PIXY system, the difference from the detected position, the difference from the position in the star catalog, are recorded in this order. When the positional difference is too large, the identification may be a mistake.

When the system could not separate close double stars, one detected star can have several counterparts in star catalog. Sometimes, several data are recorded in star catalog for one star.

N=NGC 3896
D| 11 48 56.60 +48 40 44.9  mag=13.15  x= 355.32  y= 246.40
C| GSC3452.1458  11 48 56.11  +48 40 53.3  13.52
C| GSC3452.1498  11 48 56.43  +48 40 28.3  13.17
R| NGC 3896  (galaxy)  R.A.=11h48.9m  Decl.=+48o41'  size=1.
7'  mag=14p
R| MCG+08-22-008  NGC 3896  R.A.=11 48.88  Decl.=+48 40  13.
9 mag
M| O-C(R.A., Decl.)=+4.8", -8.4"  (+0.5, -0.9 pixels)

* Some lines are forced to be folded here.

In these cases, several positional differences are recorded, for each data in star catalog.

MCG+08-22-008           RP-00002        45.0"           46.8"  36.5"  

In this example, the difference from the data at R.A. 11h48m56s.11, Decl. +48o40'53".3 is 46.8 arcsec, and the difference from the data at R.A. 11h48m56s.43, Decl. +48o40'28".3 is 36.5 arcsec.

The difference from the position in star catalog is not output for a star not recorded in star catalog (ND). The difference from the detected position is not output for a star not detected but recorded in star catalog (NC).

MCG+08-22-007           ND-00001        56.4"           
STM0895                 NC-00003                        0.1"  

The system identifies based on the positional error recorded in the identification database. Sometimes a variable star can be identified with several detected stars. The double-identified stars are recorded at the end. The name of such stars and the number of identified detected stars are output.

[Double Identifications]
NGC 3928        2
NGC 3893        2
MCG+08-22-019   2
MCG+08-22-007   2

The data of such double-identified stars appear several times in [Identification Check List]. For example, the data of NGC 3928 appears twice as follows.

NGC 3928                PS-00047        73.9"           75.2"  
NGC 3928                RM-00002        4.4"            3.8"  

The positional difference implies that RM-00002 should be the right identification and PS-00047 should be a mistake.

o Batch mode

Several PXF files can be identified at one time using a batch file containing names of all PXF files. After -identify option, set the -batch option and the name of batch file. For example, to identify with a batch file sample.bat, run the system as follows.

java   -Dmisao.home=C:\misao   misao.pixy.Pixy   -identify   -batch   sample.bat

In the batch file, write one name of PXF file in one line.


If you would like to save the verification result into a check file, write the name of check file in the same line.

sample01.pxf sample01.icl
sample02.pxf sample02.icl
sample03.pxf sample03.icl

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