36th International School for Young Astronomers24 November – 12 December 2014 @ Chiang Mai, Thailand

Photometric Observation

36th International School for Young Astronomers24 November – 12 December 2014 @ Chiang Mai, Thailand

EXO-PLANET TRANSIT: PHOTOMETRIC OBSERVATION

Qian Shengbang, Yunnan Observatories

He Jiajia , Yunnan Observatories & National Astronomical Research Institute of Thailand

Maulidiani Az Zahra, Institut Teknologi Bandung

Eranga Thiina Jayashantha University of Kelaniya Sri Lanka

Grittiya Pongsupa Chiang Mai University

Nurul Fatini Jaafar, University of Science Malaysia

(Tutors)Prof Qian Shenbang

Dr He Jiajia

(Students)Eranga Thilina Jayashantha

Maulidiani Az ZahraGrittiya PongsupaNurul Fatini Jaafar

36th International School for Young Astronomers24 November – 12 December 2014 @ Chiang Mai, Thailand

36th International School for Young Astronomers24 November – 12 December 2014 @ Chiang Mai, Thailand

1.Introduction2.Objective

3.Observation4.Result and Analysis

5.Conclusions

36th International School for Young Astronomers24 November – 12 December 2014 @ Chiang Mai, Thailand

36th International School for Young Astronomers24 November – 12 December 2014 @ Chiang Mai, Thailand

If planet passes in front of parent star, the flux/luminosityof the star will temporarily drop drawing out a light curve

36th International School for Young Astronomers24 November – 12 December 2014 @ Chiang Mai, Thailand

From period of the planet’s

orbit and period of the

transit occurred, diameter

of the planet’s orbit can be

measured.

The amount of starlight

blocked by the planet is

proportional to the cross-

sectional area of that

planet. Transit depth is

proportional to surface ratios

of planet and star. Planet

size relative to the star can

be measured.

2 types of planetary orbits in binary star system

36th International School for Young Astronomers24 November – 12 December 2014 @ Chiang Mai, Thailand

SPX

X

• Learning on how to do photometricobservation

• Learning data reduction using IRAF software

• Learning on how to do data analysis to getminimum time, error and O-C diagram

36th International School for Young Astronomers24 November – 12 December 2014 @ Chiang Mai, Thailand

• Telescope model: PlaneWave CDK24

• Aperture: 50 cm

• Focal length: 3962 mm

• Focal ratio: f/6.5

36th International School for Young Astronomers24 November – 12 December 2014 @ Chiang Mai, Thailand

• ANDOR DW936N-#BV CCD

• Active pixels 2048 x 2048

• Sensor size 2.76 x 2.76 cm

• Pixel size (W x H) 13.5 μm x 13.5 μm

• Active area pixel well depth 100,000 e-

• Readout rate used 1 MHz

• Read noise 2.9 e-

• Temperature that we used -80°C (cooling by air)

• EQ 95% (BV)

36th International School for Young Astronomers24 November – 12 December 2014 @ Chiang Mai, Thailand

No.Name of

TargetCoordinate

Observing Time(Local Time)

1TX CnC

RA:08h40m01.7sDEC:+18°59’59.5’’

01:43 – 02:50 a.m.

2 EH CNCRA:08h26m18.4sDEC:+20°52’50.0’’

02:58 – 04:15 a.m.

3 FG HyaRA:08h27m03.9sDEC:+03°30’52.3’’

04:38 – 06:00 a.m.

4 EQ TauRA:03h48m13.4sDEC:+22°18’51.0’’

09:40 – 10:40 p.m.

5 EE CetRA:02h49m52.3sDEC:+08°56’18.0’’

11:05p.m – 12:00 a.m.

• Observation date: 7 December 2014

• After midnight 7 December

• Before midnight 8 December

36th International School for Young Astronomers24 November – 12 December 2014 @ Chiang Mai, Thailand

IRAF

1. Image reduction

2. Differential Photometry

3. Aperture Photometry

ORIGIN 70

1. Light Curve Fitting

2. Time of Minimum

3. O-C Diagram

No.Name of

TargetCoordinate

Observing Time(Local Time)

Minimum TimeHJD2456900+

1TX CnC

RA:08h40m01.7sDEC:+18°59’59.5’’

01:43 – 02:50 a.m.b-band :99,29855v-band: 99,29851

2 EH CNCRA:08h26m18.4sDEC:+20°52’50.0’’

02:58 – 04:15 a.m.b-band :99,35639

v-band: 99,356393

3 FG HyaRA:08h27m03.9sDEC:+03°30’52.3’’

04:38 – 06:00 a.m.-

4 EQ TauRA:03h48m13.4sDEC:+22°18’51.0’’

09:40 – 10:40 p.m.b-band :99,29855v-band: 99,29851

5 EE CetRA:02h49m52.3sDEC:+08°56’18.0’’

11:05p.m – 12:00 a.m.b-band :99,29855v-band: 99,29851