oct 16, 2009 kaifeng

Oct 16, 2009 Kaifeng

NAOC and Steward Observatory

The South Galactic Cap U-band Sky Survey with the Bok

2.3m TelescopeFan Zhou

NAOC

1. To supply the input source catalogue for LAMOST; 2. To classify of the stars, galaxies, AGN and quasars in the south

Galactic cap region with the color-color diagram;3. To detect the red shift z<3 quasar candidates combining the

photometry in other bands;4. To estimate the red shift of the galaxies with PhotoZ combining the

photometry in other bands;5. To find out some starburst galaxies candidates;6. It can help us estimate the metallicity of the stellar populations in the

galaxies;7. To identify the type of the stars in the color-color diagram combining

the photometry in other bands, which can help us the control the completeness of the star type for the LAMOST observations;

8. It can be helpful for the flux calibration of the LAMOST spectra.

图 1 ： SDSS测光中的恒星（×），星系（△）和类星体（其中红移 z< 3.5的源用□表示，红移 z≥ 3.5的源用■表示）的双色图。

图 2 ： 1 个太阳质量，年龄是 1 Gyr的谱能量分布随金属丰度的变化。

PI: Prof. Xu Zhou

PI: Prof. Michael Lesser

The Bok

• Organization: Steward Observatory.

• Location: Kitt Peak, Arizona, USA

• Wavelength: optical, infrared

• Diameter: 2.3m (90 inches)

Location―Kitt Peak

• Altitude: 6,900 ft (2071 m)

• Latitude: +31° 57' 46.5“

• Longitude: 111°36' 01.6"W

• Time Zone: +7 hours

The Bok 90 inch (2.3 meter) Reflector Telescope

The Telescope

CCDs• Focal Plane Array• CCDs: Four Lockheed Martin CCD4185 (unpackaged =

CCD485 packaged) • Single CCD Format: 4096 x 4097 pixels • Single CCD Active Area: 61.20 mm x 61.21 mm • Inter-CCD Gap: 15.76 mm (~1050 pixels) • Total Focal Plan Array Area: 138.16 mm x 138.18 mm • Total Active Area: 122.40 mm x 122.42 mm • Total Pixel Count: 4 x 4096 x 4097 = 67125248 • Pixel Size: 15 µm • Plate Scale: 30.20"/mm • Pixel Scale: 0.453"/pixel • Edge-to-Edge Field-of-View: 1.159° x 1.159° • Active Field-of-View: 1.027° x 1.027°

CCD configuration

The CCD Overlapping

CCD QE

SDSS DR7

The U-band Sky MAP

The U-band Sky Survey

• If we got 55 nights: 55 nights ×10 hours / nights =550 hours

• Calibration: 387×3min=21 hours • Each field: (550-21)hours×3/4 clear

night/3700=6.43 min

• If we got 80 nights: 80 nights ×10 hours / nights =800 hours

• Each field: (800-21)hours×3/4 clear night/3700=9.47 min

Total Observation Time

Thank you!