DRAFT
2023-05-25 21:53:36
Type: Object/s-Data/Analysis
Bibcode: 2023TNSAN.144....1K
Pre-Discovery Magnitude Analysis vs. Time of SN 2023ixf from Serendipitous Image Frames
Authors: Ben Koltenbah
Keywords: Supernova, Transient, Time-domain, Techniques, Methods, Photometry
Abstract:
23 serendipitous image frames of M101 were acquired showing SN 2023ixf during pre-discovery times 2023-05-19 05:11 UTC through 2023-05-19 10:48 UTC. Magnitude calculations were made for each frame using 36 star flux ratios and recorded vs. acquisition time. Calculated magnitude is 16.16 +/- 0.3 at start time and 15.43 +/- 0.3 at end time. These appear to be commensurate with other reported values during this time frame. Table of magnitude results provided in this report. Raw and calibrated images are available upon request. Hardware: TSRC10 + TSFLAT3 + QHY600M-PH + Astrodon L.

23 serendipitous image frames were taken of M101 from 2023-05-19 05:11 UTC through 2023-05-19 10:48 UTC showing SN 2023ixf during this pre-discovery time range.  Using each frame, the SN flux and those of 36 neighboring stars with known magnitudes were recorded.  Star magnitudes are from GSC2.3 and located on the image using PixInsight's AnnotateImage script.  The SN magnitude was then calculated using the following formula (Reference):

m2 = m1 - 2.5 log10(f2 / f1),

where f1 is the star flux, m1 the star magnitude, f2 the SN flux, m2 the SN magnitude.  Fluxes were measured using the PixInsight process tool DynamicPSF and saved to spreadsheet.  Internal flux units are unknown, likely normalized, however this information is not required since the formula utilizes a ratio.  For each frame, the 36 calculated magnitudes were averaged and standard deviation of about 0.31 for each result was established.

Magnitudes were 16.16 +/- 0.3 at start time and 15.43 +/- 0.3 at end time during this range.  These values appear to be commensurate with others reported during this time.

DATE UTC TIME UTC SN MAG SDEV
2023-05-19 05:06:20 16.16 0.33
2023-05-19 05:16:55 16.11 0.31
2023-05-19 05:27:31 16.08 0.31
2023-05-19 05:38:06 16.03 0.31
2023-05-19 05:52:19 16.01 0.31
2023-05-19 06:02:58 15.96 0.33
2023-05-19 06:17:21 15.96 0.30
2023-05-19 06:34:08 15.89 0.31
2023-05-19 06:44:48 15.86 0.34
2023-05-19 06:55:24 15.85 0.30
2023-05-19 07:09:50 15.86 0.32
2023-05-19 07:20:26 15.78 0.31
2023-05-19 07:34:46 15.77 0.31
2023-05-19 07:45:22 15.75 0.33
2023-05-19 07:55:58 15.75 0.33
2023-05-19 08:06:34 15.77 0.31
2023-05-19 08:21:03 15.68 0.31
2023-05-19 08:31:40 15.72 0.32
2023-05-19 08:42:16 15.63 0.32
2023-05-19 09:28:26 15.55 0.31
2023-05-19 10:17:36 15.52 0.33
2023-05-19 10:28:13 15.46 0.32
2023-05-19 10:42:57 15.43 0.31

Images were taken with a TSRC10 scope with TSFLAT3 field flattener, QHY600M-PH camera and Astrodon L filter.  Raw and calibrated images are available upon request.

 

Show current TNS values
Catalog Name Reported RA Reported DEC Reported Obj-Type Reported Redshift Host Name Host Redshift DATE UTC TIME UTC (day frac) SN MAG SN MAG SDEV Remarks TNS RA TNS DEC TNS Obj-Type TNS Redshift
TNS 2023ixf 14:03:38.562 +54:18:41.94 SN IIn 0.0008 M101 14:03:38.562 +54:18:41.94 SN II 0.0008
AstroNote Publication Timestamp Title Authors
2023-120 2023-05-20 01:17:30 ZTF Pre-Discovery Forced Photometry of SN 2023ixf Daniel A. Perley (LJMU), Ido Irani (Weizmann)
File Comments
SN2023ixf Before After Image - B Koltenbah - 2023-05-19.png Before and after integrated images of M101 showing SN 2023ixf.
SN2023ixf Magnitude vs Time - B Koltenbah - 2023-05-19.png This is an image of the calculated magnitudes vs. time during the time range of the acquisition frames.

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