J/A+A/701/A32 Optical photometry of SN 2023ldh (Pastorello+, 2025)
A long-lasting eruption heralds SN 2023ldh, a clone of SN 2009ip.
Pastorello A., Reguitti A., Tartaglia L., Valerin G., Cai Y.-Z.,
Charalampopoulos P., De Luise F., Dong Y., Elias-Rosa N., Farah J.,
Farina A., Fiscale S., Fraser M., Galbany L., Gomez S.,
Gonzalez-Banuelos M., Hiramatsu D., Howell D.A., Kangas T., Killestein T.L.,
Marziani P., Mazzali P.A., Mazzotta Epifani E., McCully C., Ochner P.,
Padilla Gonzalez E., Ravi A.P., Salmaso I., Schuldt S., Schweinfurth A.G.,
Smartt S.J., Smith K.W., Srivastav S., Stritzinger M.D., Taubenberger S.,
Terreran G., Valenti S., Wang Z.-Y., Guidolin F., Gutierrez C.P.,
Itagaki K., Kiyota S., Lundqvist P., Chambers K.C., de Boer T.J.L.,
Lin C.-C., Lowe T.B., Magnier E.A., Wainscoat R.J.
<Astron. Astrophys. 701, A32 (2025)>
=2025A&A...701A..32P 2025A&A...701A..32P (SIMBAD/NED BibCode)
ADC_Keywords: Supernovae ; Photometry ; Spectroscopy ; Optical
Keywords: stars: winds, outflows - supernovae: individual: SN 2023ldh -
supernovae: individual: SN 2009ip
Abstract:
We discuss the results of the spectroscopic and photometric monitoring
of the type IIn supernova (SN) 2023ldh. Survey archive data show that
the SN progenitor experienced erratic variability in the years before
exploding. From May 2023, the source shows a general slow luminosity
rise lasting over four months with some superposed luminosity
fluctuations. In analogy to SN 2009ip, we label this brightening as
Event A. During Event A, SN 2023ldh reaches a maximum absolute
magnitude of Mr≃15.52±0.24mag. Then the light curves show a
luminosity decline of about 1mag in all filters lasting about two
weeks, followed by a steep brightening (Event B) to an absolute peak
magnitude of Mr≃18.53±0.23mag, replicating the evolution of SN
2009ip and similar SNe IIn. Three spectra of SN 2023ldh are obtained
during Event A, showing multi-component P Cygni profiles of HI and
FeII lines. During the rise to the Event B peak, the spectrum shows a
blue continuum dominated by Balmer lines in emission with Lorentzian
profiles, with a full width at half-maximum (FWHM) velocity of about
650 km/s. Later, in the post-peak phase, the spectrum reddens, and
broader wings appear in the Hα line profile. Metal lines are
well visible with P Cygni profiles and velocities of about 2000km/s.
Beginning around three months past maximum and until very late phases,
the Ca II lines become among the most prominent features, while
Hα is dominated by an intermediate-width component with a boxy
profile. Although SN 2023ldh mimics the evolution of other SN
2009ip-like transients, it is slightly more luminous and has a slower
photometric evolution. The surprisingly homogeneous observational
properties of SN 2009ip-like events may indicate similar explosion
scenarios and similar progenitor parameters.
Description:
Photometry of SN 2023ldh in the optical bands, including
Johnson-Bessell B and V (in the Vega system); Sloan u,g,r,i, and z (in
the AB system); and ATLAS-cyan and orange (in the AB system).
Objects:
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RA (2000) DE Designation(s)
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15 09 09.597 +52 31 59.80 SN 2023ld
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 103 1790 Photometric data for SN 2023ldh
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Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
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1- 10 A10 "date" Date Date, expressed as YYYY/MM/DD
13- 21 F9.3 d MJD Modified Julian Date
24- 29 A6 --- Filter Broadband filter used (1)
32- 35 A4 --- n_mag ABmag or VEGAmag system
38 A1 --- l_mag Detection limit symbol
39- 44 F6.3 mag mag Apparent magnitude
47- 51 F5.3 mag e_mag ?=- Apparent magnitude error
55- 68 A14 --- Inst Instrumental configuration (2)
71-103 A33 --- Notes Additional information
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Note (1): filters are B, V, cyan, orange and ugriz.
Note (2): Additional information on the instrumental configurations is available
in the manuscript, in Sect. 2 and in Table 2 (for spectro-photometric data).
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Acknowledgements:
Andrea Pastorello, andrea.pastorello(at)inaf.it
(End) Patricia Vannier [CDS] 18-Jul-2025