The Magnificent Five Images of Supernova Refsdal: Time Delay and Magnification Measurements

Journal Article · Thu May 11 00:00:00 UTC 2023 · The Astrophysical Journal

DOI: https://doi.org/10.3847/1538-4357/ac4ccb · OSTI ID:2483963

Kelly, Patrick L.  ^[1]; Rodney, Steven ^[2]; Treu, Tommaso  ^[3]; Birrer, Simon  ^[4]; Bonvin, Vivien  ^[5]; Dessart, Luc  ^[6]; Foley, Ryan J.  ^[7]; Filippenko, Alexei V.  ^[8]; Gilman, Daniel  ^[9]; Jha, Saurabh  ^[10]; Hjorth, Jens  ^[11]; Mandel, Kaisey  ^[12]; Millon, Martin  ^[5]; Pierel, Justin  ^[2]; Thorp, Stephen ^[13]; Zitrin, Adi  ^[14]; Broadhurst, Tom ^[15]; Chen, Wenlei  ^[1]; Diego, Jose M.  ^[16]; Dressler, Alan  ^[17] ; Graur, Or  ^[18]; Jauzac, Mathilde  ^[19]; Malkan, Matthew A.  ^[3]; McCully, Curtis  ^[20]; Oguri, Masamune  ^[21]; Postman, Marc  ^[22]; Schmidt, Kasper Borello  ^[23]; Sharon, Keren  ^[24]; Tucker, Brad E.  ^[25]; von der Linden, Anja  ^[26]; Wambsganss, Joachim  ^[27]

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1. University of Minnesota, Minneapolis, MN (United States)
2. University of South Carolina, Columbia, SC (United States)
3. University of California, Los Angeles, CA (United States)
4. Stanford University, CA (United States)
5. Ecole Polytechnique Federale de Lausanne (EPFL), Versoix (Switzerland)
6. CNRS-Sorbonne Université, Paris (France)
7. University of California, Santa Cruz, CA (United States)
8. University of California, Berkeley, CA (United States)
9. University of California, Los Angeles, CA (United States); University of Toronto, ON (Canada)
10. Rutgers University, Piscataway, NJ (United States)
11. University of Copenhagen (Denmark)
12. Institute of Astronomy and Kavli Institute for Cosmology, Cambridge (United Kingdom); University of Cambridge (United Kingdom)
13. Institute of Astronomy and Kavli Institute for Cosmology, Cambridge (United Kingdom)
14. Ben-Gurion University of the Negev, Beer-Sheva (Israel)
15. University of the Basque Country (Spain)
16. IFCA, Instituto de Física de Cantabria (UC-CSIC), Santander (Spain)
17. The Observatories of the Carnegie Institution for Science, Pasadena, CA (United States)
18. University of Portsmouth (United Kingdom); American Museum of Natural History, New York, NY (United States)
19. Durham University (United Kingdom); University of KwaZulu-Natal, Durban (South Africa)
20. Las Cumbres Observatory, Goleta, CA (United States); University of California, Santa Barbara, CA (United States)
21. University of Tokyo (Japan); Chiba University (Japan); University of Tokyo, Chiba (Japan)
22. Space Telescope Science Institute, Baltimore, MD (United States)
23. Leibniz-Institut fur Astrophysik Potsdam (AIP) (Germany)
24. University of Michigan, Ann Arbor, MI (United States)
25. Australian National University, Canberra, ACT (Australia); The ARC Centre of Excellence for All-Sky Astrophysics in 3 Dimension (ASTRO 3D) (Australia)
26. Stony Brook University, NY (United States)
27. Zentrum für Astronomie der Universität Heidelberg (ZAH) (Germany); International Space Science Institute (ISSI), Bern (Switzerland)

In late 2014, four images of supernova (SN) "Refsdal," the first known example of a strongly lensed SN with multiple resolved images, were detected in the MACS J1149 galaxy-cluster field. Following the images' discovery, the SN was predicted to reappear within hundreds of days at a new position ~8'' away in the field. The observed reappearance in late 2015 makes it possible to carry out Refsdal's original proposal to use a multiply imaged SN to measure the Hubble constant H0, since the time delay between appearances should vary inversely with H0. Moreover, the position, brightness, and timing of the reappearance enable a novel test of the blind predictions of galaxy-cluster models, which are typically constrained only by the positions of multiply imaged galaxies. We have developed a new photometry pipeline that uses DOLPHOT to measure the fluxes of the five images of SN Refsdal from difference images. We apply four separate techniques to perform a blind measurement of the relative time delays and magnification ratios between the last image SX and the earlier images S1–S4. We measure the relative time delay of SX–S1 to be 376.0$$^{+5.6}_{–5.5}$$ days and the relative magnification to be 0.30$$^{+0.5}_{–0.3}$$. This corresponds to a 1.5% precision on the time delay and 17% precision for the magnification ratios and includes uncertainties due to millilensing and microlensing. In an accompanying paper, we place initial and blind constraints on the value of the Hubble constant.

• Research Organization: Stony Brook University, NY (United States)
• Sponsoring Organization: JSPS KAKENHI; National Aeronautic and Space Administration (NASA); National Science Foundation (NSF); USDOE Office of Science (SC), High Energy Physics (HEP)
• Grant/Contract Number: SC0023387
• OSTI ID: 2483963
• Journal Information: The Astrophysical Journal, Journal Name: The Astrophysical Journal Journal Issue: 2 Vol. 948; ISSN 0004-637X
• Publisher: IOP PublishingCopyright Statement
• Country of Publication: United States
• Language: English