A Comprehensive Light-curve Model of the Very Fast Nova V1674 Herculis

V1674 Her is one of the fastest novae, of which the very early phase is well observed, including optical rise to the peak over 10 mag. We present a full theoretical light-curve model of V1674 Her. Our 1.35 M _⊙ white dwarf (WD) model with the mass accretion rate of 1 × 10 ^−11 M _⊙ yr ^−1 explains o...

Full description

Saved in:
Bibliographic Details
Main Authors: Mariko Kato, Izumi Hachisu, Hideyuki Saio
Format: Article
Language:English
Published: IOP Publishing 2025-01-01
Series:The Astrophysical Journal
Subjects:
Online Access:https://doi.org/10.3847/1538-4357/ade231
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849318205006282752
author Mariko Kato
Izumi Hachisu
Hideyuki Saio
author_facet Mariko Kato
Izumi Hachisu
Hideyuki Saio
author_sort Mariko Kato
collection DOAJ
description V1674 Her is one of the fastest novae, of which the very early phase is well observed, including optical rise to the peak over 10 mag. We present a full theoretical light-curve model of V1674 Her. Our 1.35 M _⊙ white dwarf (WD) model with the mass accretion rate of 1 × 10 ^−11 M _⊙ yr ^−1 explains overall properties including a very fast rise and decay of the optical V light curve. The WD photosphere expands up to 21 R _⊙ , thus a 0.26 M _⊙ companion star orbiting the WD every 3.67 hr is engulfed 2.7 hr after the onset of thermonuclear runaway and appears 5.3 days after that. The duration of X-ray flash is only 0.96 hr. The evolution of the expanding envelope and temporal change of the photospheric radius are very consistent with observed optical and X-ray modulations with the orbital and spin (501 s) periods. We confirm that the decay phase of the nova light curve is well approximated by a sequence of steady-state envelope solutions. Using the time-stretching method of nova light curves, we obtain the V -band distance modulus of ( m  −  M ) _V  = 16.3 ± 0.2 and determine the distance to be d  = 8.9 ± 1 kpc for the interstellar extinction of E ( B – V ) = 0.5 ± 0.05.
format Article
id doaj-art-d651fe04e6c64ab3ba4ead75b4b4cb98
institution Kabale University
issn 1538-4357
language English
publishDate 2025-01-01
publisher IOP Publishing
record_format Article
series The Astrophysical Journal
spelling doaj-art-d651fe04e6c64ab3ba4ead75b4b4cb982025-08-20T03:50:58ZengIOP PublishingThe Astrophysical Journal1538-43572025-01-01988111210.3847/1538-4357/ade231A Comprehensive Light-curve Model of the Very Fast Nova V1674 HerculisMariko Kato0https://orcid.org/0000-0002-8522-8033Izumi Hachisu1https://orcid.org/0000-0002-0884-7404Hideyuki Saio2Department of Astronomy, Keio University , Hiyoshi, Kouhoku-ku, Yokohama 223-8521, Japan ; mariko.kato@hc.st.keio.ac.jpDepartment of Earth Science and Astronomy, College of Arts and Sciences, The University of Tokyo , 3-8-1 Komaba, Meguro-ku, Tokyo 153-8902, JapanAstronomical Institute, Graduate School of Science, Tohoku University , Sendai 980-8578, JapanV1674 Her is one of the fastest novae, of which the very early phase is well observed, including optical rise to the peak over 10 mag. We present a full theoretical light-curve model of V1674 Her. Our 1.35 M _⊙ white dwarf (WD) model with the mass accretion rate of 1 × 10 ^−11 M _⊙ yr ^−1 explains overall properties including a very fast rise and decay of the optical V light curve. The WD photosphere expands up to 21 R _⊙ , thus a 0.26 M _⊙ companion star orbiting the WD every 3.67 hr is engulfed 2.7 hr after the onset of thermonuclear runaway and appears 5.3 days after that. The duration of X-ray flash is only 0.96 hr. The evolution of the expanding envelope and temporal change of the photospheric radius are very consistent with observed optical and X-ray modulations with the orbital and spin (501 s) periods. We confirm that the decay phase of the nova light curve is well approximated by a sequence of steady-state envelope solutions. Using the time-stretching method of nova light curves, we obtain the V -band distance modulus of ( m  −  M ) _V  = 16.3 ± 0.2 and determine the distance to be d  = 8.9 ± 1 kpc for the interstellar extinction of E ( B – V ) = 0.5 ± 0.05.https://doi.org/10.3847/1538-4357/ade231Classical novaeStellar windsX-ray binary stars
spellingShingle Mariko Kato
Izumi Hachisu
Hideyuki Saio
A Comprehensive Light-curve Model of the Very Fast Nova V1674 Herculis
The Astrophysical Journal
Classical novae
Stellar winds
X-ray binary stars
title A Comprehensive Light-curve Model of the Very Fast Nova V1674 Herculis
title_full A Comprehensive Light-curve Model of the Very Fast Nova V1674 Herculis
title_fullStr A Comprehensive Light-curve Model of the Very Fast Nova V1674 Herculis
title_full_unstemmed A Comprehensive Light-curve Model of the Very Fast Nova V1674 Herculis
title_short A Comprehensive Light-curve Model of the Very Fast Nova V1674 Herculis
title_sort comprehensive light curve model of the very fast nova v1674 herculis
topic Classical novae
Stellar winds
X-ray binary stars
url https://doi.org/10.3847/1538-4357/ade231
work_keys_str_mv AT marikokato acomprehensivelightcurvemodeloftheveryfastnovav1674herculis
AT izumihachisu acomprehensivelightcurvemodeloftheveryfastnovav1674herculis
AT hideyukisaio acomprehensivelightcurvemodeloftheveryfastnovav1674herculis
AT marikokato comprehensivelightcurvemodeloftheveryfastnovav1674herculis
AT izumihachisu comprehensivelightcurvemodeloftheveryfastnovav1674herculis
AT hideyukisaio comprehensivelightcurvemodeloftheveryfastnovav1674herculis