A study in scarlet -- I. Photometric properties of a sample of Intermediate Luminosity Red Transients

Abstract

We investigate the photometric characteristics of a sample of Intermediate Luminosity Red Transients (ILRTs), a class of elusive objects with peak luminosity between that of classical novae and standard supernovae. We present the multi-wavelength photometric follow-up of four ILRTs, namely NGC 300 2008OT-1, AT 2019abn, AT 2019ahd and AT 2019udc. Through the analysis and modelling of their spectral energy distribution and bolometric light curves we infer the physical parameters associated with these transients. All four objects display a single peaked light curve which ends in a linear decline in magnitudes at late phases. A flux excess with respect to a single black body emission is detected in the infrared domain for three objects in our sample, a few months after maximum. This feature, commonly found in ILRTs, is interpreted as a sign of dust formation. Mid infrared monitoring of NGC 300 2008OT-1 761 days after maximum allows us to infer the presence of $\sim$10${}^{-3}$-10${}^{-5}$ M${}_{\odot }$ of dust, depending on the chemical composition and the grain size adopted. The late time decline of the bolometric light curves of the considered ILRTs is shallower than expected for ${}^{56}$Ni decay, hence requiring an additional powering mechanism. James Webb Space Telescope observations of AT 2019abn prove that the object has faded below its progenitor luminosity in the mid-infrared domain, five years after its peak. Together with the disappearance of NGC 300 2008OT-1 in Spitzer images seven years after its discovery, this supports the terminal explosion scenario for ILRTs. With a simple semi-analytical model we try to reproduce the observed bolometric light curves in the context of few M${}_{\odot }$ of material ejected at few 10${}^3$ km s${}^{-1}$ and enshrouded in an optically thick circumstellar medium.

21 pages, 15 figures plus 20 additional pages of data in appendix. Submitted to A&A

References in corpus (36)

• Wilkinson Microwave Anisotropy Probe (WMAP) Three Year Results: Implications for Cosmology
• The James Webb Space Telescope
• The Zwicky Transient Facility: Science Objectives
• GROND - a 7-channel imager
• Characterizing the V-band light-curves of hydrogen-rich type II supernovae
• PESSTO : survey description and products from the first data release by the Public ESO Spectroscopic Survey of Transient Objects
• The Supernova Channel of Super-AGB Stars
• Super and massive AGB stars - IV. Final fates - Initial to final mass relation
• SN 2005cs in M51 II. Complete Evolution in the Optical and the Near-Infrared
• A New Class of Luminous Transients and A First Census of Their Massive Stellar Progenitors
• The Automatic Learning for the Rapid Classification of Events (ALeRCE) Alert Broker
• The 2008 Luminous Optical Transient in the Nearby Galaxy NGC 300
• An Intermediate Luminosity Transient in NGC300: The Eruption of a Dust-Enshrouded Massive Star
• The timing and location of dust formation in the remnant of SN 1987A
• SN 2008S: A Cool Super-Eddington Wind in a Supernova Impostor
• Dynamics of shock propagation and nucleosynthesis conditions in O-Ne-Mg core supernovae
• The ACS Nearby Galaxy Survey Treasury V. Radial Star Formation History of NGC 300
• The electron-capture origin of supernova 2018zd
• Electron-capture supernovae exploding within their progenitor wind
• A Spitzer/IRS Spectrum of the 2008 Luminous Transient in NGC 300: Connection to Proto-Planetary Nebulae
• A Luminous Red Nova in M31 and its Progenitor System
• Radiation-hydrodynamical modelling of underluminous type II plateau Supernovae
• Luminous Red Nova AT 2019zhd, a new merger in M 31
• Graphite Revisited
• Disentangling Dust Components in SN 2010jl: The First 1400 Days
• The Evolution of Luminous Red Nova AT 2017jfs in NGC 4470
• Low luminosity Type II supernovae -- IV. SN 2020cxd and SN 2021aai, at the edges of the sub-luminous supernovae class
• Volumetric rates of Luminous Red Novae and Intermediate Luminosity Red Transients with the Zwicky Transient Facility
• Synthetic observables for electron-capture supernovae and low-mass core collapse supernovae
• Low luminosity Type II supernovae III. SN 2018hwm, a faint event with an unusually long plateau
• The Carnegie Supernova Project II. Observations of the intermediate luminosity red transient SNhunt120
• Observations of the Optical Transient in NGC 300 with AKARI/IRC: Possibilities of Asymmetric Dust Formation
• Transient Classifiers for Fink: Benchmarks for LSST
• JWST Imaging of the Cartwheel Galaxy Reveals Dust Associated with SN 2021afdx
• Time varying Na I D absorption in ILRTs as a probe of circumstellar material
• A study in scarlet -- II. Spectroscopic properties of a sample of Intermediate Luminosity Red Transients

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