Download MACHO Project

Database of Variable Stars
Bingqiu Chen
Dept of Astronomy
Beijing Normal University
Outline
Pulsating Variable Stars
Data
MACHO
OGLE
MySQL
Database design
Future work
Pulsating Variable Stars
The pulsating stars swell and
shrink regularly by stellar radius,
magnitude and spectrum.
The two most important types:
Cepheids and cepheid-like stars.
Long Period Variables.
Variable star observations
Long period
Long-term observation projects
Microgravitational Lensing projects!
MACHO & OGLE
MACHO Project
MAssive Compact Halo Object
Method: photometry monitor of
several millions stars for a period
of years
Observation
50 inch telescope
B & R filters
2*4* 2048*2048 CCDs
high data rate (several GBytes per
night)
Data from MACHO
~27,000 images since June 1992.
Two colors for 8 million stars in
the LMC & SMC and 10 million in
the bulge of the Milky Way
Retrieval 21747 variable stars
data
Data of MACHO
Data of MACHO
Data of MACHO
OGLE Project
The Optical Gravitational Lensing
Experiment
Phases
OGLE-I: 1992 -1995, filter I, 1-m Swope
telescope,2048×2048 CCD
OGLE-II: 1997-2001, BVI photometry, 1.3-m
Warsaw telescope,2048×2048 CCD
OGLE-III: 2001- , eight chip 8192 8192 pixel
mosaic. Each chip of the mosaicis a SITe ST002a CCD detector with 2048 4096 pixels of
15 μm size
Data from OGLE (Variable Stars )
Galactic Bulge:Variable Stars(200 000
objects)
Magellanic Clouds:Variable Stars(68 000
objects)
LMC
Eclipsing binary stars(2580 objects)
RR Lyr stars(7612 objects)
Cepheids(1414 objects)
Ellipsoidal Variability of Red Giants(1670 objects)
SMC
Eclipsing binary stars in the SMC (2809 objects)
RR Lyr stars from the SMC (571 objects)
Cepheids from the SMC (2159 objects)
Other:Cepheids in the Galaxy IC1613 (138
objects)
Data of OGLE
Bulge
var_stars(I,B,V)
ic1613:cep
LMC:cep;ecl;ell;lpv;rrlyr
SMC:cep;ecl;rrlyr
Dia(I)
ac:LMC;SMC (.flux,.mag)
MySQL
The software to build the database
The MySQL® software delivers a
very fast, multi-threaded, multiuser, and robust SQL (Structured
Query Language) database server
Model Build
Entity
Relationship between entities
Attribute
ID
Standardization
OGLE data model :Entity & Attribute
Star:starID,Ra,Dec.
Position:positionID,position(LMC,S
MC,buldge,ic1613)
Imag:ImagID,JD,Imag,Imagerr
Iflux:IfluxID,JD,Iflux,Ifluxerr
Type:typeID,type(ac,cep,ecl,ell,lpv,
rrlyr)
Idia:IDiaID,JD,Idia,Idiaerr
B;V;I ( same as Idia )
OGLE data model: Relationship
MACHO data model: Entity &
Attribute
Star:StarID, Ra,Dec
(same as OGLE:connection)
Minfor:MinforID, MACHOID,
observations, inceptionJD,
Rmag,Bmag, chip coordinates, westchunk, Pixel coordinate system
Infor:InforID,JD,Obsid,Pier,Exposure,Ch
ecklist,Airmass,rMag, rErr,rDS,rTF,rCP
rX2,rMP,rCR,rA,rXpix,rYpix,rSky,rFWHM
,Tobs,r,bMag,bErr,bDS,bTF,bCP,bX2
bMP,bCR,bA,bXpix,bYpix,bSky,bFWHM
bTobs,b
MACHO data model: Relationship
As one single database
Notice the entity star.
Both MACHO’s and OGLE’s have
the same attributes
Add a entity:
income:incomeID,income(OGLE,
MACHO)
Physcal database design
Entity
table
Attribute
array
ID
not null array
(primary key)
Relationship
forign key
Table
Array
Data type
Note
star
starID
int
primary key
RA(1)
ascII(2)
RA(2)
ascII(2)
RA(3)
ascII(2)
DEC(1)
ascII(2)
DEC(2)
ascII(2)
DEC(3)
ascII(2)
positionID
int
forign key
typeID
int
forign key
incomeID
int
forign key
positionID
int
primary key
position
vachar(8)
incomeID
int
income
vachar(8)
typeID
int
type
vachar(6)
ImagID
int
Imag
ascii(16)
Imagerr
ascii(16)
starID
int
forign key
IfluxID
int
primary key
Iflux
ascii(16)
Ifluxerr
ascii(16)
starID
int
position
income
type
Imag
Iflux
primary key
primary key
primary key
forign key
RA 05 09 28.213 DEC -68 47 51.45
6
4
R(MACHO)
B+2(MACHO)
I-11(OGLE)
2
0
-2
-4
-6
-8
-10
-12
-14
4.85
4.9
4.95
5
5.05
TIME (JD)
5.1
5.15
5.2
4
RA 05 28 51.783 DEC -70 00 44.75
6
4
R(MACHO)
B+2(MACHO)
I-20(OGLE)
2
0
-2
-4
-6
-8
-10
-12
4.85
4.9
4.95
5
5.05
Time(JD 2000)
5.1
5.15
5.2
4
x 10
Future work
Data read
Database
Science analysis…
Types
The two most important types are:
Cepheids and cepheid-like stars.
They have short periods (days to
months) and their luminosity cycle
is very regular;
Long Period Variables. Their
period is longer, on the order of a
year, and much less regular.
MACHO Project
MAssive Compact Halo Objects
Mount Stromlo Observatory, Canberra, Australia.
Telescope & CCDs
50 inch telescope.
2*4* 2048*2048 CCDs
high data rate (several GBytes per
night)
OGLE
The Optical Gravitational Lensing
Experiment
1.3 m Warsaw University Telescope Las Campanas
Observatory, Chile
Telescope technical data
1.3m (51'') primary mirror diameter
1:9.2 (1:2.8 primary) Ritchey-Chretién system; 17.4
arcsec/mm focal scale
3-element field corrector - 1.5° diffraction limited field (80%
of light within 0.5 arcsec diameter)
Ultra Low Expansion (ULE) glass mirrors
Fully automated, computer controlled operation
Fork, paralactic mount, friction drives (no backlash) allowing
any tracking rate in RA and DEC
Light, steel enclosure with Ash-dome dome, easy ventilation
(louvers on telescope and ground level). Minimalization of
heat sources in the telescope building
Remote control of the telescope and instruments from
"control building" located 15 m away from the telescope
building. Possibility of remote control over the Internet
First "optical" light Feb 9, 1996, first "electronic" light Jul 18,
1996
CCD Camera
Single chip camera (OGLE-II, 1997-2001)
SITe 2048×2049 thin chip
90% QE over wide range from B to I, also some
sensitivity in U
0.4 arcsec/pixel scale
5 e- readout noise at 3.8 e-/ADU (16-bit ADC: 65535
levels)
modular control system developed at Warsaw University
Observatory - easily expandable to multi-chip mosaic,
next generation cameras
"Second generation" mosaic camera (OGLE-III, 2001...)
eight thin SITe 2048×4096 CCD chips (total of
8192×8192 pixels)
0.26 arcsec/pixel scale, 35'×35' total field of view
6-9 e- readout noise (depending on chip) at 1.3 e-/ADU
gain
98 seconds readout time
Auto-Guiding System and Filter
Wheel
512×512 pixels EEV CCD37 detector
driven by the same electronics as
scientific CCD (2.2 by 2.2 arcmin field)
Automatic positioning of the guider
probe with accuracy of 2 pixels over the
entire field of view
Automatically positioned filter wheel with
7 slots for up to 16 cm diameter filters.
Standard UBVRI filters installed
Data from OGLE (analogous to
MACHO)
ftp://bulge.princeton.edu/ogle/ogle
2/dia/
Catalogs of concrete type of
variables (Cepheids, RR Lyraes,
eclipsing variables):
ftp://bulge.princeton.edu/ogle/ogle
2/var_stars/