The HST See Change Program: I. Survey Design, Pipeline, and Supernova Discoveries
Brian Hayden
,
David Rubin
,
Kyle Boone
,
Greg Aldering
,
Jakob Nordin
,
Mark Brodwin
,
Susana Deustua
,
Sam Dixon
,
Parker Fagrelius
,
Andy Fruchter
,
Peter Eisenhardt
,
Anthony Gonzalez
,
Ravi Gupta
,
Isobel Hook
,
Chris Lidman
,
Kyle Luther
,
Adam Muzzin
,
Zachary Raha
,
Pilar Ruiz-Lapuente
,
Clare Saunders
,
Caroline Sofiatti
,
Adam Stanford
,
Nao Suzuki
,
Tracy Webb
,
Steven C. Williams
,
Gillian Wilson
,
Mike Yen
,
Rahman Amanullah
,
Kyle Barbary
,
Hans Bohringer
,
Greta Chappell
,
Carlos Cunha
,
Miles Currie
,
Rene Fassbender
,
Michael Gladders
,
Ariel Goobar
,
Hendrik Hildebrandt
,
Henk Hoekstra
,
Xiaosheng Huang
,
Dragan Huterer
,
M. James Jee
,
Alex Kim
,
Marek Kowalski
,
Eric Linder
,
Joshua E. Meyers
,
Reynald Pain
(1)
,
Saul Perlmutter
,
Johan Richard
(2)
,
Piero Rosati
,
Eduardo Rozo
,
Eli Rykoff
,
Joana Santos
,
Anthony Spadafora
,
Daniel Stern
,
Risa Wechsler
Brian Hayden
- Function : Author
David Rubin
- Function : Author
- PersonId : 793031
- ORCID : 0000-0001-5647-1723
Kyle Boone
- Function : Author
Greg Aldering
- Function : Author
Jakob Nordin
- Function : Author
Mark Brodwin
- Function : Author
Susana Deustua
- Function : Author
Sam Dixon
- Function : Author
Parker Fagrelius
- Function : Author
Andy Fruchter
- Function : Author
Peter Eisenhardt
- Function : Author
Anthony Gonzalez
- Function : Author
- PersonId : 794096
- ORCID : 0000-0002-0933-8601
Ravi Gupta
- Function : Author
Isobel Hook
- Function : Author
Chris Lidman
- Function : Author
- PersonId : 759871
- ORCID : 0000-0003-1731-0497
Kyle Luther
- Function : Author
Adam Muzzin
- Function : Author
Zachary Raha
- Function : Author
Pilar Ruiz-Lapuente
- Function : Author
Clare Saunders
- Function : Author
Caroline Sofiatti
- Function : Author
Adam Stanford
- Function : Author
Nao Suzuki
- Function : Author
Tracy Webb
- Function : Author
Steven C. Williams
- Function : Author
Gillian Wilson
- Function : Author
Mike Yen
- Function : Author
Rahman Amanullah
- Function : Author
Kyle Barbary
- Function : Author
Hans Bohringer
- Function : Author
Greta Chappell
- Function : Author
Carlos Cunha
- Function : Author
Miles Currie
- Function : Author
Rene Fassbender
- Function : Author
Michael Gladders
- Function : Author
Ariel Goobar
- Function : Author
Hendrik Hildebrandt
- Function : Author
Henk Hoekstra
- Function : Author
Xiaosheng Huang
- Function : Author
Dragan Huterer
- Function : Author
M. James Jee
- Function : Author
Alex Kim
- Function : Author
Marek Kowalski
- Function : Author
Eric Linder
- Function : Author
Joshua E. Meyers
- Function : Author
Saul Perlmutter
- Function : Author
Piero Rosati
- Function : Author
Eduardo Rozo
- Function : Author
Eli Rykoff
- Function : Author
Joana Santos
- Function : Author
Anthony Spadafora
- Function : Author
Daniel Stern
- Function : Author
Risa Wechsler
- Function : Author
Abstract
The See Change survey was designed to make z > 1 cosmological measurements by efficiently discovering high-redshift Type Ia supernovae (SNe Ia) and improving cluster mass measurements through weak lensing. This survey observed twelve galaxy clusters with the Hubble Space Telescope (HST) spanning the redshift range z = 1.13–1.75, discovering 57 likely transients and 27 likely SNe Ia at z ∼ 0.8–2.3. As in similar previous surveys, this proved to be a highly efficient use of HST for supernova observations; the See Change survey additionally tested the feasibility of maintaining, or further increasing, the efficiency at yet higher redshifts, where we have less detailed information on the expected cluster masses and star formation rates. We find that the resulting number of SNe Ia per orbit is a factor of ∼8 higher than for a field search, and 45% of our orbits contained an active SN Ia within 22 rest-frame days of peak, with one of the clusters by itself yielding 6 of the SNe Ia. We present the survey design, pipeline, and supernova discoveries. Novel features include fully blinded supernova searches, the first random forest candidate classifier for undersampled IR data (with a 50% detection threshold within 0.05 mag of human searchers), real-time forward-modeling photometry of candidates, and semi-automated photometric classifications and follow-up forecasts. We also describe the spectroscopic follow-up, instrumental in measuring host galaxy redshifts. The cosmology analysis of our sample will be presented in a companion paper.