NICMOS Status 2014 Rodger Thompson - Steward Observatory, University of Arizona Calibration Workshop August 11, 2014 STScI

Basic Status Both the Near Infrared Camera and Multi- Object Spectrometer, NICMOS, and the NICMOS Cooling System, NCS, are in hold mode. NICMOS is warm and must be cooled to be operational. The NCS must be purged to remove any water and refilled with neon gas from the on-board auxiliary tank. All procedures are in place for NCS restart and NICMOS recovery.

The NICMOS Cooling System

NCS Images

Calibration Strategy NICMOS would only be recovered to utilize capabilities not duplicated or exceeded by other instruments. Calibration would most likely only be carried out for those capabilities when they are required. There are no current plans to recover NICMOS

Unique Imaging Capabilities High resolution imaging with Camera 1, arc sec. pixels Camera 2, arc sec. pixels Imaging longer than 1.7 microns Imaging in unique broad and medium band filters

NICMOS View of the Pillars of “Creation”

Unique Line Imaging filters Atomic Hydrogen Pa  –  m Br  –  m Molecular Hydrogen S1 –  m Helium  m Metals [S III] –  m [Si VI] –  m

The Egg Nebula F110W BLUE F160W GREEN H 2 RED G. Schneider

Planetary and Stellar Atmosphere Molecular Band Filters F180M HCO 2 and C 2 F204M Methane F237M CO

Imaging in Polarized Light Camera 1 POL0S POL120S POL240S Camera 2 POL0L POL120L POL240L

Polarization Image IRAS Prop Dean Hines F160W NIC2 POL

Infrared Coronagraphic Imaging Coronographic hole in camera 2 NGC 2264 G. Schneider

WHAT NEXT There are no current plans to restore NICMOS to operational status. All systems appear to be nominal. At the time of last operation there appeared to be no sign of detector degradation. The NCS can be restarted and NICMOS returned to operation via commands from the ground.

Using the Archive “The NICMOS instrument, which began taking data in 1997, was so cutting-edge that ground- based technology is only now beginning to match its power. Because Hubble has been in operation for 24 years, it provides a long baseline of high-quality archival observations. Now, with such new technologies in image processing, we can go back to the archive and conduct research more precisely than previously possible with NICMOS data," STScI Press Release April 24, 2014

New Stellar Disks from Old NICMOS Data

Known Calibration Issues Two Epochs of Calibration Solid Nitrogen Cooled NCS Cooled 2002 – Now Persistence Faint residual images after reset Quad-bias DC offsets between detector quadrants

Known Calibration Issues cont. History dependent “dark current” Subsequent reads have different “dark current” subtractions Experience with reference pixels in more recent detectors show that this is not true dark current. Non-Linearity Mitigated by up the ramp sampling.

Bottom Line Know what has been done to your NICMOS data. For Deep Field images you may wish to start with the raw data and process it yourself. Know what is in the headers. Most of it is there for a reason.

Fair Warning Beware of Fred! There is no ring around Mars!