SN 2023ixf was a bright supernova in the Pinwheel galaxy M 101 in constellation UMa. With maximum brightness of V~11.0 mag (end of May 2023) it was easily reachable whithin the Alpy600 spectrograph.
It needed good weather conditions for sprctra recording. At start time of the spectroscopy session the object had an altitude of 77°, at the end it was at 54° a really comfortable position.
| Position: | RA 14h 03m 38s.562, DEC +54° 18' 41".94 |
| Host galaxy: | M 101, z=0.000804 |
| Discovery: | 2023-05-19.727 by Koichi Itagaki |
| max. Brightness: | V~11.05 mag (around 2023-05-26 00:00 UT) |
| Type of SN: | IIP |

2023-05-21 22:09 - 22:26 UT, Roof Observatory Kaufering, 14" ACF teleskop on Taurus GM-60 mount, CCD camera: Moravian G2-8300FW, 3x3 Binning, L-filter, 42x60s; magnitude measured with Astrometrica: V=11.5 mag;
See SN 2023ixf at Latest Supernovae page for more information and images.
Spectra of this supernova:

2023-05-26 22:21 - 00:25 UT, Roof Observatory Kaufering,
Meade 14" ACF telescope on Taurus GM-60 mount, Astro Physics reducer CCDT67,
Alpy600 with guiding unit, CCD camera: Atik 428EX, guiding camera: ASI 120 MM; recording software: AstroArt, guiding software: PHD2
Wavelength calibration: Hg lines from energy saving lamp and Ne lines from flicker flame light bulbs,
instrumental response calibration: with reference star HIP 668196 (HD 122007), A3V, data reduction: with
Integrated Spectrographic Innovative Software from Christian Buil;
The spectrum has been cut at the near UV end (3710 Å) due to strong noise.

2023-06-03 22:30 - 00:47 UT, Roof Observatory Kaufering,
Meade 14" ACF telescope on Taurus GM-60 mount, Astro Physics reducer CCDT67,
Alpy600 with guiding unit, CCD camera: Atik 428EX, guiding camera: ASI 120 MM; recording software: AstroArt, guiding software: PHD2
Wavelength calibration: Hg lines from energy saving lamp and Ne lines from flicker flame light bulbs,
instrumental response calibration: with reference star HIP 67848 (HD 121489), A0V, data reduction: with
Integrated Spectrographic Innovative Software from Christian Buil;
The spectrum has been cut at the near UV end (3750 Å) due to strong noise.

2023-06-09 22:47 - 01:09 UT, Roof Observatory Kaufering,
Meade 14" ACF telescope on Taurus GM-60 mount, Astro Physics reducer CCDT67,
Alpy600 with guiding unit, CCD camera: Atik 428EX, guiding camera: ASI 120 MM; recording software: AstroArt, guiding software: PHD2
Wavelength calibration: Hg lines from energy saving lamp and Ne lines from flicker flame light bulbs,
instrumental response calibration: with reference star HIP 67848 (HD 121489), A0V, data reduction: with
Integrated Spectrographic Innovative Software from Christian Buil;
The spectrum has been cut at the near UV end (3710 Å) due to strong noise.

2023-06-16 21:22 - 01:50 UT, Roof Observatory Kaufering,
Meade 14" ACF telescope on Taurus GM-60 mount, Astro Physics reducer CCDT67,
Alpy600 with guiding unit, CCD camera: Atik 428EX, guiding camera: ASI 120 MM; recording software: AstroArt, guiding software: PHD2
Wavelength calibration: Hg lines from energy saving lamp and Ne lines from flicker flame light bulbs,
instrumental response calibration: with reference star HIP 67848 (HD 121489), A0V, data reduction: with
Integrated Spectrographic Innovative Software from Christian Buil;
The spectrum has been cut at the near UV end (3730 Å) due to strong noise.

2023-06-24 21:03 - 01:46 UT, Roof Observatory Kaufering,
Meade 14" ACF telescope on Taurus GM-60 mount, Astro Physics reducer CCDT67,
Alpy600 with guiding unit, CCD camera: Atik 428EX, guiding camera: ASI 120 MM; recording software: AstroArt, guiding software: PHD2
Wavelength calibration: Hg lines from energy saving lamp and Ne lines from flicker flame light bulbs,
instrumental response calibration: with reference star HIP 67848 (HD 121489), A0V, data reduction: with
Integrated Spectrographic Innovative Software from Christian Buil;
The spectrum has been cut at the near UV end (3730 Å) due to strong noise.

2023-07-07 21:34 - 22:55 UT, Roof Observatory Kaufering,
Meade 14" ACF telescope on Taurus GM-60 mount, Astro Physics reducer CCDT67,
Alpy600 with guiding unit, CCD camera: Atik 428EX, guiding camera: ASI 120 MM; recording software: AstroArt, guiding software: PHD2
Wavelength calibration: Hg lines from energy saving lamp and Ne lines from flicker flame light bulbs,
instrumental response calibration: with reference star HIP 67848 (HD 121489), A0V, data reduction: with
Integrated Spectrographic Innovative Software from Christian Buil;
The spectrum has been cut at the near UV end (3765 Å) due to strong noise.

2023-07-08 22:17 - 01:06 UT, Roof Observatory Kaufering,
Meade 14" ACF telescope on Taurus GM-60 mount, Astro Physics reducer CCDT67,
Alpy600 with guiding unit, CCD camera: Atik 428EX, guiding camera: ASI 120 MM; recording software: AstroArt, guiding software: PHD2
Wavelength calibration: Hg lines from energy saving lamp and Ne lines from flicker flame light bulbs,
instrumental response calibration: with reference star HIP 67848 (HD 121489), A0V, data reduction: with
Integrated Spectrographic Innovative Software from Christian Buil;
The spectrum has been cut at the near UV end (3760 Å) due to strong noise.
The classification with independent methods shows a type:IIP.
1) Classification with GELATO
(Padova-Asiago Supernova Group), see [1].


Spectrum from 2023-05-26 second best matches to SN 2008es (IIL pec) with an age of 12.5 d (Quality factor: 0.88); the age is too old.


Spectrum from 2023-06-03 second best matches to SN 2008es (IIL pec) with an age of 50.0 d (Quality factor: 1.13); the age is definitly wrong!


Spectrum from 2023-06-09 best matches to SN 2007od (IIP) with an age of 6.4 d (Quality factor: 1.65); the age is too young.


Spectrum from 2023-06-16 second best matches to SN 2007od (IIP) with an age of 13.5 d (Quality factor: 2.67); the age is too young.


Spectrum from 2023-06-24 best matches to SN 1995ad (IIP) with an age of 23.9 d (Quality factor: 3.18); the age is too young.


Spectrum from 2023-07-07 third best matches to SN 2007od (IIP) with an age of 46.4 d (Quality factor: 3.05); the age is good (50 days since explosion).


Spectrum from 2023-07-08 third best matches to SN 2007od (IIP) with an age of 46.4 d (Quality factor: 2.91); the age is al little bit too young (52 days since explosion).
2) Classification with SNID
(SuperNova IDentification), see [2].

Spectrum from 2023-05-26 best matches to SN 2004et (IIP) with an age of -2 d
The age of -2 dis quite good estimated (around maximum brightness).

Spectrum from 2023-06-03 11th match to SN 1979C (IIL) with an age of 13 d - visually the best match.
The given age of 13 d is probably 5 days too late.

Spectrum from 2023-06-09 11th match to SN 2006Y (IIP) with an age of 27 d - visually the best match.
The given age of 27 d is probably 14 days too late.

Spectrum from 2023-06-16 best match to SN 2004ET (IIP) with an age of 10 d - visually the best match.
The given age of 10 d is probably 10 days too young.

Spectrum from 2023-06-24 best match to SN 2004ET (IIP) with an age of 10 d - visually the best match.
The given age of 10 d is probably 18 days too young.

Spectrum from 2023-07-07 sixth best match to SN 2006bp (IIP) with an age of 20 d - visually the best match.
The given age of 20 d is probably 21 days too young.

Spectrum from 2023-07-08 10th best match to SN 1992H (IIP) with an age of 44 d - visually the best match.
The given age of 44 d is quite good.
In both tools the red shift (z=0.000804) of host galaxy has been entered.
Note: The age in GELATO is given in days since explosion, wheras the age in SNID is given in days since maximum brightness.
Light curves are available at:
WISeREP: light curves of SN 2023ixf and
AAVSO: light curve of SN 2023ixf
Has not been done yet.
In days since maximum brightness

The H-Alpha emission becomes stronger, the blue shift of absorption feature becomes less in wavelength and stronger in intensity, hence the ejected material is slower. There is a lack of light in the blue part in later spectrum.
References:
[1] Harutyunyan et al., 2008, A&A, 488, 383
[2] Blondin & Tonry 2007, ApJ, 666, 1024
[3] Shappee et al. (2014) and
Kochanek et al. (2017)
[4] R.O. Gray, C.J. Corbally, Stellar Spectral Classification, Princeton University Press, 2009
[5] A.V. Filippenko, Optical Spectra of Supernovae, Annu. Rev. Astron. Astrophys. 1997. 35,309,55
My other spectroscopic observations: Spektroskopie (mostly in German)
[ updated: 2026-06-12 |
Gregor Krannich
| Gregors astronomy page ]