Search for the progenitor of SN 2023ixf in archival AstroSat UVIT images
ATel #16064; Judhajeet Basu, Sudhanshu Barway, G. C. Anupama, RIshabh SIngh Teja, Anirban Dutta From Indian Institute of Astrophysics (IIA)
on 30 May 2023; 08:55 UT
Distributed as an Instant Email Notice Supernovae
Credential Certification: Sudhanshu Barway (sudhanshu.barway@iiap.res.in)
The progenitor of the type II supernova SN 2023ixf discovered by Koichi Itagaki (https://www.wis-tns.org/object/2023ixf) in M101 on 19/05/2023 has been searched for in multi-wavelengths using archival data. There have been detections of a progenitor in the optical: HST data (Atel #16040) and the mid-IR: Spitzer data (Atel #16042), while there has been no detection in the X-ray bands: Chandra (Atel #16051) and XMM-Newton (Atel #16060). The optical and mid-IR data indicate the progenitor to be a red supergiant
We searched the AstroSat-UVIT L1 archives to look for the UV counterpart of the progenitor star in the data obtained in 2016 between July 30 and August 2. M101 was observed with the UVIT in 8 different filters: 4 in FUV and 4 in NUV, all with the observation ID G05_233T10_9000000570. UVIT L1 data was reduced using CCDLAB (Postma and Leahy, 2017), and photometry was performed using standard procedures. We do not find the progenitor star in all 8 images. We performed aperture photometry at the location of the supernova (RA 14:03:38.562, Dec. +54:18:41.94) with an aperture size of 2 arcsecs to determine the upper limits in the UV bands. The upper limits are
Date of Obs. | Filter | Exposure (secs) | Upper Limit (AB mag)
2016-07-31.23 | FUV_CaF2 (F148W) | 3280 | 21.68
2016-07-31.64 | FUV_BaF2 (F154W) | 3731 | 21.50
2016-08-01.38 | FUV_Sapphire (F169M) | 6011 | 21.40
2016-08-02.34 | FUV_Silica (F172M) | 4708 | 21.26
2016-07-31.23. | NUV_NUVB15 (N219M) | 8097 | 21.38
2016-08-01.45 | NUV_NUVB13 (N245M) | 3091 | 21.29
2016-08-01.79 | NUV_NUVB4 (N263M) | 3528 | 21.19
2016-08-02.54 | NUV_NUVN2 (N279N) | 3319 | 21.18
The AstroSat UVIT images can be viewed at ---
https://drive.google.com/file/d/1GtoBkMMrOitxlYDwprdgtfLfTAhPBdQf/view?usp=sharing
We thank the AstroSat team, members of ISSDC at ISRO, and UVIT-POC at IIA for making the archival data available for public download.
