The Absolute Magnitudes of 1991T-like Supernovae

Abstract

1991T-like supernovae are the luminous, slow-declining extreme of the Branch shallow-silicon (SS) subclass of Type Ia supernovae. They are distinguished by extremely weak Ca II H & K and Si II $\lambda 6355$ and strong Fe III absorption features in their optical spectra at pre-maximum phases, and have long been suspected to be over-luminous compared to normal Type Ia supernovae. In this paper, the pseudo equivalent width of the Si II $\lambda$6355 absorption obtained at light curve phases from $\le +10$ days is combined with the morphology of the $i$-band light curve to identify a sample of 1991T-like supernovae in the Carnegie Supernova Project-II. Hubble diagram residuals show that, at optical as well as near-infrared wavelengths, these events are over-luminous by $\sim$0.1-0.5 mag with respect to the less extreme Branch SS (1999aa-like) and Branch core-normal supernovae with similar $B$-band light curve decline rates.

arXiv commentSubmitted to ApJ (Aug 30, 2022)

References in corpus (57)

• Observational Evidence from Supernovae for an Accelerating Universe and a Cosmological Constant
• Measurements of Omega and Lambda from 42 High-Redshift Supernovae
• Maps of Dust IR Emission for Use in Estimation of Reddening and CMBR Foregrounds
• Measuring Reddening with SDSS Stellar Spectra and Recalibrating SFD
• A 2.4% Determination of the Local Value of the Hubble Constant
• The Man Behind the Curtain: X-rays Drive the UV through NIR Variability in the 2013 AGN Outburst in NGC 2617
• The All-Sky Automated Survey for Supernovae (ASAS-SN) Light Curve Server v1.0
• The Carnegie-Chicago Hubble Program. VIII. An Independent Determination of the Hubble Constant Based on the Tip of the Red Giant Branch
• Nearby Supernova Rates from the Lick Observatory Supernova Search. II. The Observed Luminosity Functions and Fractions of Supernovae in a Complete Sample
• The Reddening-Free Decline Rate Versus Luminosity Relationship for Type Ia Supernovae
• A Precise Distance Indicator: Type Ia Supernova Multicolor Light Curve Shapes
• Cosmic Distances Calibrated to 1% Precision with Gaia EDR3 Parallaxes and Hubble Space Telescope Photometry of 75 Milky Way Cepheids Confirm Tension with LambdaCDM
• The Absolute Luminosities of the Calan/Tololo Type Ia Supernovae
• The type Ia supernova SNLS-03D3bb from a super-Chandrasekhar-mass white dwarf star
• Determining the Type, Redshift, and Age of a Supernova Spectrum
• Type Iax Supernovae: A New Class of Stellar Explosion
• Evidence for a Spectroscopic Sequence Among SNe Ia
• UBVRI Light Curves of 44 Type Ia Supernovae
• Nearby Supernova Factory Observations of SN 2007if: First Total Mass Measurement of a Super-Chandrasekhar-Mass Progenitor
• SN 2002cx: The Most Peculiar Known Type Ia Supernova
• PESSTO : survey description and products from the first data release by the Public ESO Spectroscopic Survey of Transient Objects
• Berkeley Supernova Ia Program I: Observations, Data Reduction, and Spectroscopic Sample of 582 Low-Redshift Type Ia Supernovae
• Optical Photometry of the Type Ia SN 1999ee and the Type Ib/c SN 1999ex in IC 5179
• The Carnegie Supernova Project: Light Curve Fitting with SNooPy
• Comparative Direct Analysis of Type Ia Supernova Spectra. II. Maximum Light
• The Spectroscopic Diversity of Type Ia Supernovae
• A Search for Environmental Effects on Type Ia Supernovae
• The Carnegie Supernova Project: Intrinsic Colors of Type Ia Supernovae
• Spectrophotometric time series of SN 2011fe from the Nearby Supernova Factory
• The Peculiar SN 2005hk: Do Some Type Ia Supernovae Explode as Deflagrations?
• A High Intrinsic Peculiarity Rate Among Type Ia Supernovae
• The Carnegie Supernova Project: Absolute Calibration and the Hubble Constant
• Optical and Infrared Spectroscopy of SN 1999ee and SN 1999ex
• Nearby Supernova Rates from the Lick Observatory Supernova Search. I. The Methods and Database
• Measuring the Hubble constant with Type Ia supernovae as near-infrared standard candles
• Optical Light Curves of the Type Ia Supernovae 1990N and 1991T
• Spectroscopy of Type Ia Supernovae by the Carnegie Supernova Project
• Optical and Infrared Photometry of the Type Ia Supernovae 1991T, 1991bg, 1999ek, 2001bt, 2001cn, 2001cz, and 2002bo
• Spectroscopic Observations and Analysis of the Peculiar SN 1999aa
• Comparative Direct Analysis of Type Ia Supernova Spectra. V. Insights from A Larger Sample and Quantitative Subclassification
• Berkeley Supernova Ia Program II: Initial Analysis of Spectra Obtained Near Maximum Brightness
• Carnegie Supernova Project-II: Extending the Near-Infrared Hubble Diagram for Type Ia Supernovae to $z\sim 0.1$
• On the Spectrum and Nature of the Peculiar Type Ia Supernova 1991T
• High velocity features in the spectra of the Type Ia SN 1999ee: a property of the explosion or evidence of circumstellar interaction?
• Near-Infrared Properties of Type Ia Supernovae
• The Exceptionally Luminous Type Ia Supernova 2007if
• The MASTER-II Network of Robotic Optical Telescopes. First Results
• Surface Radioactivity or Interactions? Multiple Origins of Early-excess Type Ia Supernovae and Associated Subclasses
• Cepheid Calibration of the Peak Brightness of SNe Ia. X. SN 1991T in NGC 4527
• Abundance stratification in Type Ia Supernovae - IV: the luminous, peculiar SN 1991T
• Carnegie Supernova Project: The First Homogeneous Sample of "Super-Chandrasekhar Mass"/2003fg-like Type Ia Supernova
• Type Ia Supernovae are Excellent Standard Candles in the Near-Infrared
• Berkeley Supernova Ia Program: Data Release of 637 Spectra from 247 Type Ia Supernovae
• Carnegie Supernova Project-II: A new method to photometrically identify sub-types of extreme Type Ia Supernovae
• Carnegie Supernova Project: Classification of Type Ia Supernovae
• Spectroscopically Peculiar Type Ia Supernovae and Implications for Progenitors
• Early ultraviolet emission in the Type Ia supernova LSQ12gdj: No evidence for ongoing shock interaction

Cited by in corpus (10)

• Type Ia Supernova Explosions in Binary Systems: A Review
• Carnegie Supernova Project-II: Near-infrared spectral diversity and template of Type Ia Supernovae
• ZTF SN Ia DR2: The spectral diversity of Type Ia supernovae in a volume-limited sample
• Type Ia Supernova Progenitor Properties and Their Host Galaxies
• SN 2021fxy: Mid-Ultraviolet Flux Suppression is a Common Feature of Type Ia Supernovae
• Type Ia supernova constraints on compact object dark matter
• Hawai'i Supernova Flows: A Peculiar Velocity Survey Using Over a Thousand Supernovae in the Near-Infrared
• Characterising the Standardisation Properties of Type Ia Supernovae in the z band with Hierarchical Bayesian Modelling
• Deciphering the explosion mechanism of Type Ia SNe using their remnants II: a deep dive into double detonations with SNR 0509-67.5
• Normal or transitional? The evolution and properties of two type Ia supernovae in the Virgo cluster