Lawrence Berkeley National LaboratoryHigh Resistivity CCDs

in Ground Based Astronomy

Richard Stover, Mingzhi Wei, William BrownUniversity of California Observatories/Lick Observatory

The University of CaliforniaSanta Cruz, California

September, 2006

Wide band filter @ 700nm Narrow band filter @1000nm

First astronomical images with QE>60% at 1000nm.Using UCO/Lick 1-m Nickel Telescope and LBNL200x200 backside-illuminated high-resistivity CCD.4 December, 1996

Orion Nebula

A. 200x200 B. 2Kx2K C. 1294x4196 (12μm) D. 2Kx4K E. 400x690 (24 μm) F. 470x1264

A B C D

E F

LBNL CCDs Packaged at UCO/Lick

UCO/Lick Cold Wafer Probe Station

UCO/Lick Cold Wafer Probe Station

UCO/Lick Class 100 Cleanroom

Packaged 2Kx4KPackaged 2Kx4K

Advantages of High Resistivity CCDs

The LBNL high resistivity CCDs offer three advantages for ground-based astronomical imaging compared to previous CCDs.

1. Very high quantum efficiency at wavelengths greater than about 700nm.

2. No internal interference fringes.

3. Reduced charge diffusion.

QE comparisons of various CCDs used at Keck

A Keck LRIS spectrograph flat-field spectrum obtained by I. M. Hookprocessed to illustrate the interference patterns produced in the CCD

~5%

Image courtesy Don Groom, LBNL

Disadvantagesof

High Resistivity CCDs

Worms and cosmic rays

LBNL 2Kx4K CCD

1000 s Dark

Ground-based Astronomy Applicationsof

High-Resistivity CCDs

UCO/Lick Hamilton echelle spectrograph (one 2Kx2K CCD)UCO/Lick Kast Cassegrain spectrograph (planned)UCO/Lick Nickel Telescope direct camera (planned)UCO/Lick guide cameras (4 cameras) (one 400x690 or 470x1264 CCD)NOAO MARS spectrograph (one 1980x800 CCD)NOAO RC spectrograph (one 1980x800 CCD)Keck LRIS spectrograph (red-side) (planned, 2 2Kx4K CCDs)Fermilab DES camera for Cerro Tololo 4-m Blanco telescope (planned, 62 2Kx4K CCDs)

Non-LBNL high resistivity CCD projects:HyperSuprime Camera for Subaru telescope (planned, 176 2Kx4K Hamamatsu CCDs)

Results from the NOAOMulti Aperture RedSpectrometer (MARS)on the Kitt Peak 4-mTelescope

Data courtesy of Xiaohui Fan froma study of SDSS-identified high-redshift quasars. Originally pub-lished in NOAO newsletter

MARS observation of the 6th most distant quasar knownand the most distant radio-loud source known

Data courtesy of Daniel Stern (NASA/JPL)

A T4.5 brown dwarf, one of the 50 coldest stars known

Data courtesy of Daniel Stern (NASA/JPL)

Dark Energy Survey

● Four Probes of Dark Energy– Galaxy Cluster counting

● 20,000 clusters to z=1 with M > 2x1014 M

– Weak lensing● 300 million galaxies with shape

measurements over 5000 sq deg.

– Spatial clustering of galaxies● 300 million galaxies to z = 1

and beyond

– Standard Candles● 2000 SN Ia, z = 0.3-0.8

• 3 sq-degree camera with ≥ 2.2 deg FOV• 62 CCDs, 2kx4k – 0.5G pixel focal plane • SDSS g,r,i,z filters covering 400 to 1100nm• 10 Limiting mag: 24.6, 24.1, 24.3, 23.9• Pixel size 15 microns, 0.27” /pixel• Readout time ~17 sec.

Science Program Instrument Description

Survey Area5000 sq. deg.in SouthernGalactic Capwith connection toSDSS stripe 82 forcalibration

Brenna Flaugher for the DES Collaboration; DPF Meeting August 27, 2004 Riverside,CAFermilab, U Illinois, U Chicago, LBNL, CTIO/NOAO

High Resistivity CCD Sources

LBNL – Natalie Roe, Steven Holland, etc.

Hamamatsu Photonics K.K. Subaru Telescope, N.O.A. Japan will use up to 176 2Kx4K 15-μm pixel CCDs in HyperSuprime.

E2V Technologies Prototyping up to 2Kx4K 13.5-μm pixel CCDs.