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arXiv · 1703.02402

The First Data Release from SweetSpot: 74 Supernovae in 36 Nights on WIYN+WHIRC

Anja Weyant·W. M. Wood-Vasey·Richard Joyce·Lori Allen·Peter Garnavich·Saurabh W. Jha·Jessica R. Kroboth·Thomas Matheson·Kara A. Ponder
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Abstract

SweetSpot is a three-year National Optical Astronomy Observatory (NOAO) Survey program to observe Type Ia supernovae (SNe Ia) in the smooth Hubble flow with the WIYN High-resolution Infrared Camera (WHIRC) on the WIYN 3.5-m telescope. We here present data from the first half of this survey, covering the 2011B-2013B NOAO semesters, and consisting of 493 calibrated images of 74 SNe Ia observed in the rest-frame near-infrared (NIR) from $0.02 < z < 0.09$. Because many observed supernovae require host galaxy subtraction from templates taken in later semesters, this release contains only the 186 NIR ($JHK_s$) data points for the 33 SNe Ia that do not require host-galaxy subtraction. The sample includes 4 objects with coverage beginning before the epoch of B-band maximum and 27 beginning within 20 days of B-band maximum. We also provide photometric calibration between the WIYN+WHIRC and Two-Micron All Sky Survey (2MASS) systems along with light curves for 786 2MASS stars observed alongside the SNe Ia. This work is the first in a planned series of three SweetSpot Data Releases. Future releases will include the full set of images from all 3 years of the survey, including host-galaxy reference images and updated data processing and host-galaxy reference subtraction. SweetSpot will provide a well-calibrated sample that will help improve our ability to standardize distance measurements to SNe Ia, examine the intrinsic optical-NIR colors of SNe Ia at different epochs, explore nature of dust in other galaxies, and act as a stepping stone for more distant, potentially space-based surveys.

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BibTeXRIS

Anja Weyant, W. M. Wood-Vasey, Richard Joyce, Lori Allen, Peter Garnavich, Saurabh W. Jha, Jessica R. Kroboth, Thomas Matheson, Kara A. Ponder. 2017-03-03. The First Data Release from SweetSpot: 74 Supernovae in 36 Nights on WIYN+WHIRC. https://doi.org/10.3847/1538-3881%2Faab901

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