Reddening, Absorption, and Decline Rate Corrections for a Complete Sample of Type Ia Supernovae Leading to a Fully Corrected Hubble Diagram tov< 30,000 km s−1

SummaryObservations of Type Ia supernovae (SNe Ia) reveal correlations between their luminosities and light-curve shapes, and between their spectral sequence and photometric sequence. Assuming SNe Ia do not evolve at different redshifts, the Hubble diagram of SNe Ia may indicate an accelerating Universe, the signature of a cosmological constant or other forms of dark energy. Several studies raise concerns about the evolution of SNe Ia (e.g., the peculiarity rate, the rise time, and the color of SNe Ia at different redshifts), but all these studies suffer from the difficulties of obtaining high-quality spectroscopy and photometry for SNe Ia at high redshifts. There are also some troubling cases of SNe Ia that provide counter examples to the observed correlations, suggesting that a secondary parameter is necessary to describe the whole SN Ia family. Understanding SNe Ia both observationally and theoretically will be the key to boosting confidence in the SN Ia cosmological results.

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Theoretical Light Curves for Type Ia Supernovae and Determination of the Hubble Constant

Symposium - International Astronomical Union ◽

10.1017/s0074180900132139 ◽

1999 ◽

Vol 183 ◽

pp. 68-68

Author(s):

Koichi Iwamoto ◽

Ken'Ichi Nomoto

Keyword(s):

Hubble Constant ◽

Light Curves ◽

Type Ia Supernovae ◽

Maximum Brightness ◽

Decline Rate ◽

Type Ia ◽

Error Bars ◽

Ia Supernovae ◽

Distance Indicators

The large luminosity (MV ≈ −19 ∼ −20) and the homogeneity in light curves and spectra of Type Ia supernovae(SNe Ia) have led to their use as distance indicators ultimately to determine the Hubble constant (H0). However, an increasing number of the observed samples from intermediate- and high-z (z ∼ 0.1 − 1) SN Ia survey projects(Hamuy et al. 1996, Perlmutter et al. 1997) have shown that there is a significant dispersion in the maximum brightness (∼ 0.4 mag) and the brighter-slower correlation between the brightness and the postmaximum decline rate, which was first pointed out by Phillips(1993). By taking the correlation into account, Hamuy et al.(1996) gave an estimate of H0 within the error bars half as much as previous ones.

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Correcting for peculiar velocities of Type Ia supernovae in clusters of galaxies

Astronomy and Astrophysics ◽

10.1051/0004-6361/201832932 ◽

2018 ◽

Vol 615 ◽

pp. A162 ◽

Cited By ~ 3

Author(s):

P.-F. Léget ◽

M. V. Pruzhinskaya ◽

A. Ciulli ◽

E. Gangler ◽

G. Aldering ◽

...

Keyword(s):

Galaxy Clusters ◽

Virgo Cluster ◽

Type Ia Supernovae ◽

Hubble Diagram ◽

Cosmological Redshift ◽

Peculiar Velocity ◽

Peculiar Velocities ◽

Velocity Correction ◽

Type Ia ◽

Ia Supernovae

Context. Type Ia supernovae (SNe Ia) are widely used to measure the expansion of the Universe. To perform such measurements the luminosity and cosmological redshift (z) of the SNe Ia have to be determined. The uncertainty on z includes an unknown peculiar velocity, which can be very large for SNe Ia in the virialized cores of massive clusters. Aims. We determine which SNe Ia exploded in galaxy clusters using 145 SNe Ia from the Nearby Supernova Factory. We then study how the correction for peculiar velocities of host galaxies inside the clusters improves the Hubble residuals. Methods. We found 11 candidates for membership in clusters. We applied the biweight technique to estimate the redshift of a cluster. Then, we used the galaxy cluster redshift instead of the host galaxy redshift to construct the Hubble diagram. Results. For SNe Ia inside galaxy clusters, the dispersion around the Hubble diagram when peculiar velocities are taken into account is smaller compared with a case without peculiar velocity correction, which has a wRMS = 0.130 ± 0.038 mag instead of wRMS = 0.137 ± 0.036 mag. The significance of this improvement is 3.58σ. If we remove the very nearby Virgo cluster member SN2006X (z < 0.01) from the analysis, the significance decreases to 1.34σ. The peculiar velocity correction is found to be highest for the SNe Ia hosted by blue spiral galaxies. Those SNe Ia have high local specific star formation rates and smaller stellar masses, which is seemingly counter to what might be expected given the heavy concentration of old, massive elliptical galaxies in clusters. Conclusions. As expected, the Hubble residuals of SNe Ia associated with massive galaxy clusters improve when the cluster redshift is taken as the cosmological redshift of the supernova. This fact has to be taken into account in future cosmological analyses in order to achieve higher accuracy for cosmological redshift measurements. We provide an approach to do so.

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Can Differences in the Nickel Abundance in Chandrasekhar‐Mass Models Explain the Relation between the Brightness and Decline Rate of Normal Type Ia Supernovae?

The Astrophysical Journal ◽

10.1086/318428 ◽

2001 ◽

Vol 547 (2) ◽

pp. 988-994 ◽

Cited By ~ 85

Author(s):

Paolo A. Mazzali ◽

Ken’ichi Nomoto ◽

Enrico Cappellaro ◽

Takayoshi Nakamura ◽

Hideyuki Umeda ◽

...

Keyword(s):

Type Ia Supernovae ◽

Normal Type ◽

Decline Rate ◽

Type Ia ◽

Ia Supernovae

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The dependence of Type Ia Supernovae salt2 light-curve parameters on host galaxy morphology

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa3173 ◽

2020 ◽

Vol 499 (4) ◽

pp. 5121-5135

Author(s):

M V Pruzhinskaya ◽

A K Novinskaya ◽

N Pauna ◽

P Rosnet

Keyword(s):

Light Curve ◽

Host Galaxy ◽

Type Ia Supernovae ◽

Distance Modulus ◽

Early Type ◽

Late Type ◽

Hubble Diagram ◽

Type Ia ◽

Ia Supernovae ◽

Galaxy Morphology

ABSTRACT Type Ia Supernovae (SNe Ia) are widely used to measure distances in the Universe. Despite the recent progress achieved in SN Ia standardization, the Hubble diagram still shows some remaining intrinsic dispersion. The remaining scatter in supernova luminosity could be due to the environmental effects that are accounted for as mass step correction in the current cosmological analyses. In this work, we compare the local and global colour (U − V), the local star formation rate, and the host stellar mass to the host galaxy morphology. The observed trends suggest that the host galaxy morphology is a relevant parameter to characterize the SN Ia environment. Therefore, we study the influence of host galaxy morphology on light-curve parameters of SNe Ia from the pantheon cosmological supernova sample. We determine the Hubble morphological type of host galaxies for a subsample of 330 SNe Ia. We confirm that the salt2 stretch parameter x1 depends on the host morphology with the p-value ∼10−14. The supernovae with lower stretch value are hosted mainly by elliptical and lenticular galaxies. No correlation for the salt2 colour parameter c is found. We also examine Hubble diagram residuals for supernovae hosted by ‘early-type’ and ‘late-type’ morphological groups of galaxies. The analysis reveals that the mean distance modulus residual in early-type galaxies is smaller than the one in late-type galaxies, which means that early-type galaxies contain brighter supernovae after stretch and colour corrections. However, we do not observe any difference in the residual dispersion for these two morphological groups. The obtained results are in the line with other analyses showing environmental dependence of SN Ia light-curve parameters and luminosity. We confirm the importance of including a host galaxy parameter into the standardization procedure of SNe Ia for further cosmological studies.

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A Hubble diagram of distant type IA supernovae

The Astronomical Journal ◽

10.1086/117251 ◽

1995 ◽

Vol 109 ◽

pp. 1 ◽

Cited By ~ 245

Author(s):

Mario Hamuy ◽

M. M. Phillips ◽

Jose Maza ◽

Nicholas B. Suntzeff ◽

R. A. Schommer ◽

...

Keyword(s):

Type Ia Supernovae ◽

Hubble Diagram ◽

Type Ia ◽

Ia Supernovae

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The Standardizability of Type Ia Supernovae in the Near-Infrared: Evidence for a Peak-Luminosity Versus Decline-Rate Relation in the Near-Infrared

Publications of the Astronomical Society of the Pacific ◽

10.1086/664734 ◽

2012 ◽

Vol 124 (912) ◽

pp. 114-127 ◽

Cited By ~ 49

Author(s):

ShiAnne Kattner ◽

Douglas C. Leonard ◽

Christopher R. Burns ◽

M. M. Phillips ◽

Gastón Folatelli ◽

...

Keyword(s):

Near Infrared ◽

Type Ia Supernovae ◽

Decline Rate ◽

Type Ia ◽

Ia Supernovae ◽

Rate Relation ◽

Peak Luminosity

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Carnegie Supernova Project-II: Extending the Near-infrared Hubble Diagram for Type Ia Supernovae to z ∼ 0.1

Publications of the Astronomical Society of the Pacific ◽

10.1088/1538-3873/aae8bd ◽

2018 ◽

Vol 131 (995) ◽

pp. 014001 ◽

Cited By ~ 19

Author(s):

M. M. Phillips ◽

Carlos Contreras ◽

E. Y. Hsiao ◽

Nidia Morrell ◽

Christopher R. Burns ◽

...

Keyword(s):

Near Infrared ◽

Type Ia Supernovae ◽

Hubble Diagram ◽

Type Ia ◽

Ia Supernovae

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Optical and UV studies of type Ia supernovae SN 2009ig and SN 2012cg

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz1358 ◽

2019 ◽

Vol 487 (2) ◽

pp. 1886-1904 ◽

Cited By ~ 2

Author(s):

N K Chakradhari ◽

D K Sahu ◽

G C Anupama

Keyword(s):

Maximum Velocity ◽

Absolute Magnitude ◽

Type Ia Supernovae ◽

Strength Ratio ◽

Rate Parameter ◽

Spectral Evolution ◽

Maximum Phase ◽

Decline Rate ◽

Type Ia ◽

Ia Supernovae

Abstract We present an extensive optical–ultraviolet photometry and analysis of a series of optical spectra of type Ia supernovae SN 2009ig and SN 2012cg. The observations range from −15 to +185 d for SN 2009ig and from −14 to 316 d for SN 2012cg, with respect to maximum light in B band. Both SN 2009ig and SN 2012cg exhibit similar properties. They have similar decline rate parameter (Δm15(B)true = 0.92 ± 0.04 for SN 2009ig and 0.93 ± 0.06 for SN 2012cg) and B band peak absolute magnitude (−19.45 ± 0.40 mag for SN 2009ig and −19.50 ± 0.31 mag for SN 2012cg). Their early spectra show high-velocity features in Si ii and Ca ii lines. The strong Fe iii, Si iii, and weak Si ii λ5972 line during pre-maximum phase are indicative of hot photosphere. The post-maximum velocity evolution shows a plateau like phase with velocities ∼13 000 km s−1 for SN 2009ig and ∼10 000 km s−1 for SN 2012cg. Both events show spectral evolution similar to normal SNe Ia and fall in LVG and Core Normal subgroup. Both have smaller strength ratio [$\cal R$(Si ii) = 0.17 for SN 2009ig and 0.20 for SN 2012cg] consistent with smaller Δm15(B). Peak bolometric luminosities ($\log L_\text{bol}^\text{max}$) of these events are estimated as 43.17 ± 0.16 and 43.24 ± 0.11 erg s−1 suggesting that 0.60 ± 0.20 M⊙ of 56Ni was synthesized in the explosion of SN 2009ig and 0.72 ± 0.31 M⊙ in SN 2012cg.

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