A Calibration of NICMOS Camera 2 for Low Count-Rates
arXiv:1502.01026 · doi:10.1088/0004-6256/149/5/159
Abstract
NICMOS 2 observations are crucial for constraining distances to most of the existing sample of z > 1 SNe Ia. Unlike the conventional calibration programs, these observations involve long exposure times and low count rates. Reciprocity failure is known to exist in HgCdTe devices and a correction for this effect has already been implemented for high and medium count-rates. However observations at faint count-rates rely on extrapolations. Here instead, we provide a new zeropoint calibration directly applicable to faint sources. This is obtained via inter-calibration of NIC2 F110W/F160W with WFC3 in the low count-rate regime using z ~ 1 elliptical galaxies as tertiary calibrators. These objects have relatively simple near-IR SEDs, uniform colors, and their extended nature gives superior signal-to-noise at the same count rate than would stars. The use of extended objects also allows greater tolerances on PSF profiles. We find ST magnitude zeropoints (after the installation of the NICMOS cooling system, NCS) of 25.296 +- 0.022 for F110W and 25.803 +- 0.023 for F160W, both in agreement with the calibration extrapolated from count-rates 1,000 times larger (25.262 and 25.799). Before the installation of the NCS, we find 24.843 +- 0.025 for F110W and 25.498 +- 0.021 for F160W, also in agreement with the high-count-rate calibration (24.815 and 25.470). We also check the standard bandpasses of WFC3 and NICMOS 2 using a range of stars and galaxies at different colors and find mild tension for WFC3, limiting the accuracy of the zeropoints. To avoid human bias, our cross-calibration was "blinded" in that the fitted zeropoint differences were hidden until the analysis was finalized.
arXiv commentAccepted for Publication in the Astronomical Journal. New version contains added reference
References in corpus (35)
- Stellar population synthesis at the resolution of 2003
- The Seventh Data Release of the Sloan Digital Sky Survey
- Type Ia Supernova Discoveries at z>1 From the Hubble Space Telescope: Evidence for Past Deceleration and Constraints on Dark Energy Evolution
- Accelerating Universes with Scaling Dark Matter
- CANDELS: The Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey
- CANDELS: The Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey - The Hubble Space Telescope Observations, Imaging Data Products and Mosaics
- New Hubble Space Telescope Discoveries of Type Ia Supernovae at z > 1: Narrowing Constraints on the Early Behavior of Dark Energy
- Cosmological Results from High-z Supernovae
- The Hubble Space Telescope Cluster Supernova Survey: V. Improving the Dark Energy Constraints Above z>1 and Building an Early-Type-Hosted Supernova Sample
- Cosmic-Ray Rejection by Laplacian Edge Detection
- Spectra and Light Curves of Six Type Ia Supernovae at 0.511 < z < 1.12 and the Union2 Compilation
- The Photometric Performance and Calibration of the HST Advanced Camera For Surveys
- Cluster Lensing And Supernova survey with Hubble (CLASH): An Overview
- The Chandra Deep Field South: Optical Spectroscopy I
- Caltech Faint Galaxy Redshift Survey X: A Redshift Survey in the Region of the Hubble Deep Field North
- The Great Observatories Origins Deep Survey. VLT/FORS2 Spectroscopy in the GOODS-South Field: Part III
- The VIMOS VLT Deep Survey: Public release of 1599 redshifts to IAB<=24 across the Chandra Deep Field South
- The Team Keck Treasury Redshift Survey of the GOODS-North Field
- The Great Observatories Origins Deep Survey - VLT/VIMOS Spectroscopy in the GOODS-South Field: Part II
- An Atlas of Galaxy Spectral Energy Distributions from the Ultraviolet to the Mid-Infrared
- Discovery of an X-ray-Luminous Galaxy Cluster at z=1.4
- A Highly Complete Spectroscopic Survey of the GOODS-N Field
- Type Ia Supernova Rate Measurements to Redshift 2.5 from CANDELS : Searching for Prompt Explosions in the Early Universe
- Type-Ia Supernova Rates to Redshift 2.4 from CLASH: the Cluster Lensing And Supernova survey with Hubble
- Photometric Redshifts in the IRAC Shallow Survey
- Chandra and XMM-Newton Observations of RDCS1252.9-2927, A Massive Cluster at z=1.24
- A Spectroscopic Survey of the Galaxy Cluster CL 1358+62 at z=0.328
- An Intensive HST Survey for z>1 Supernovae by Targeting Galaxy Clusters
- RX J0911+05: A Massive Cluster Lens at z=0.769
- Lensed Type Ia Supernovae as Probes of Cluster Mass Models
- Precision Measurement of The Most Distant Spectroscopically Confirmed Supernova Ia with the Hubble Space Telescope
- The Hubble Space Telescope Cluster Supernova Survey: III. Correlated Properties of Type Ia Supernovae and Their Hosts at 0.9 < z < 1.46
- HST-NICMOS Color Transformations and Photometric Calibrations
- Multi-wavelength observations of a rich galaxy cluster at z ~ 1: the HST/ACS colour-magnitude diagram
- Constraining dust and color variations of high-z SNe using NICMOS on Hubble Space Telescope