Optimizing Type Ia supernova follow-up in future dark energy surveys

AbstractWe compare two Type Ia supernova samples that are drawn from a spectroscopically confirmed Type Ia supernova sample: a host-selected sample in which SNe Ia are restricted to those that have a spectroscopic redshift from the host; and a broader, more traditional sample in which the redshift could come from either the SN or the host. The host-selected sample is representative of SN samples that will use the redshift of the host to infer the SN redshift, long after the SN has faded from view. We find that SNe Ia that are selected on the availability of a redshift from the host differ from SNe Ia that are from the broader sample. The former tend to be redder, have narrower light curves, live in more massive hosts, and tend to be at lower redshifts. We find that constraints on the equation of state of dark energy, w, and the matter density, ΩM, remain consistent between these two types of samples. Our results are important for ongoing and future supernova surveys, which unlike previous supernova surveys, will have limited real-time follow-up to spectroscopically classify the SNe they discover. Most of the redshifts in these surveys will come from the hosts.

Download Full-text

Early Blue Excess from the Type Ia Supernova 2017cbv

Proceedings of the International Astronomical Union ◽

10.1017/s1743921318002193 ◽

2017 ◽

Vol 14 (S339) ◽

pp. 47-49

Author(s):

G. Hosseinzadeh

Keyword(s):

Light Curve ◽

Standard Type ◽

Circumstellar Material ◽

Type Ia Supernova ◽

Unusual Distribution ◽

Photometric Observations ◽

Type Ia ◽

Optical Light Curve ◽

Ia Supernovae

AbstractThis paper presented very early, high-cadence photometric observations of the nearby Type Ia SN 2017cbv. The light-curve is unique in that during the first five days of observations it has a blue bump in the U, B, and g bands which is clearly resolved by virtue of our photometric cadence of 5.7 hr during that time span. We modelled the light-curve as the combination of an early shock of the supernova ejecta against a non-degenerate companion star plus a standard Type Ia supernova component. Our best-fit model suggested the presence of a subgiant star 56 R⊙ from the exploding white dwarf, although that number is highly model-dependent. While the model matches the optical light-curve well, it over-predicts the flux expected in the ultraviolet bands. That may indicate that the shock is not a blackbody, perhaps because of line blanketing in the UV. Alternatively, it could point to another physical explanation for the optical blue bump, such as interaction with circumstellar material or an unusual distribution of the element Ni. Early optical spectra of SN 2017cbv show strong carbon absorption as far as day –13 with respect to maximum light, suggesting that the progenitor system contained a significant amount of unburnt material. These results for SN 2017cbv illustrate the power of early discovery and intense follow-up of nearby supernovæ for resolving standing questions about the progenitor systems and explosion mechanisms of Type Ia supernovæ.

Download Full-text

Measuring Time Dependence of Dark Energy Density from Type Ia Supernova Data

The Astrophysical Journal ◽

10.1086/320552 ◽

2001 ◽

Vol 552 (2) ◽

pp. 445-451 ◽

Cited By ~ 79

Author(s):

Yun Wang ◽

Peter M. Garnavich

Keyword(s):

Dark Energy ◽

Energy Density ◽

Time Dependence ◽

Measuring Time ◽

Dark Energy Density ◽

Type Ia Supernova ◽

Type Ia

Download Full-text

Consequences for some dark energy candidates from the type Ia supernova SN 1997ff

Monthly Notices of the Royal Astronomical Society ◽

10.1046/j.1365-8711.2002.05253.x ◽

2002 ◽

Vol 331 (3) ◽

pp. 776-784 ◽

Cited By ~ 40

Author(s):

R. G. Vishwakarma

Keyword(s):

Dark Energy ◽

Type Ia Supernova ◽

Type Ia

Download Full-text

THE EFFECT OF DIFFERENT OBSERVATIONAL DATA IN CONSTRAINING COSMOLOGICAL PARAMETERS

International Journal of Modern Physics Conference Series ◽

10.1142/s201019451200579x ◽

2012 ◽

Vol 10 ◽

pp. 85-94 ◽

Cited By ~ 5

Author(s):

YUNGUI GONG ◽

QING GAO ◽

ZONG-HONG ZHU

Keyword(s):

Dark Energy ◽

Equation Of State ◽

Observational Data ◽

Cosmological Parameters ◽

State Parameter ◽

Wilkinson Microwave Anisotropy Probe ◽

Model Parameters ◽

Type Ia Supernova ◽

Equation Of State Parameter ◽

Type Ia

We use the SNLS3 compilation of 472 type Ia supernova data, the baryon acoustic oscillation measurement of distance, and the cosmic microwave background radiation data from the seven year Wilkinson Microwave Anisotropy Probe to study the effect of their different combinations on the fittings of cosmological parameters. Neither BAO nor WMAP7 data alone gives good constraint on the equation of state parameter of dark energy, but both WMAP7 data and BAO data help type Ia supernova data break the degeneracies among the model parameters, hence tighten the constraint on the variation of equation of state parameter wa, and WMAP7 data does the job a little better. Although BAO and WMAP7 data provide reasonably good constraints on Ωm and Ωk, it is not able to constrain the dynamics of dark energy, we need SNe Ia data to probe the property of dark energy, especially the variation of the equation of state parameter of dark energy. For the SNLS SNe Ia data, the nuisance parameters α and β are consistent for all different combinations of the above data. Their impacts on the fittings of cosmological parameters are minimal. ΛCDM model is consistent with current observational data.

Download Full-text

Future Type Ia Supernova Data as Tests of Dark Energy from Modified Friedmann Equations

The Astrophysical Journal ◽

10.1086/376899 ◽

2003 ◽

Vol 594 (1) ◽

pp. 25-32 ◽

Cited By ~ 77

Author(s):

Yun Wang ◽

Katherine Freese ◽

Paolo Gondolo ◽

Matthew Lewis

Keyword(s):

Dark Energy ◽

Friedmann Equations ◽

Type Ia Supernova ◽

Type Ia

Download Full-text

Type Ia Supernova Discoveries atz> 1 from theHubble Space Telescope: Evidence for Past Deceleration and Constraints on Dark Energy Evolution

The Astrophysical Journal ◽

10.1086/383612 ◽

2004 ◽

Vol 607 (2) ◽

pp. 665-687 ◽

Cited By ~ 2933

Author(s):

Adam G. Riess ◽

Louis‐Gregory Strolger ◽

John Tonry ◽

Stefano Casertano ◽

Henry C. Ferguson ◽

...

Keyword(s):

Dark Energy ◽

Energy Evolution ◽

Space Telescope ◽

Type Ia Supernova ◽

Type Ia

Download Full-text

CPL effective dark energy from the backreaction effect

Modern Physics Letters A ◽

10.1142/s0217732319501670 ◽

2019 ◽

Vol 34 (21) ◽

pp. 1950167

Author(s):

Yan-Hong Yao ◽

Xin-He Meng

Keyword(s):

Dark Energy ◽

Equation Of State ◽

Perfect Fluid ◽

Coming Out ◽

Hubble Parameter ◽

Small Scale ◽

Type Ia Supernova ◽

Type Ia ◽

The Difference ◽

The Universe

In this paper, we interpret the dark energy as an effect caused by small-scale inhomogeneities of the universe with the use of the spatial averaged approach of Buchert [Gen. Relat. Gravit. 32, 105 (2000); 33, 1381 (2001)]. The model considered here adopts the Chevallier–Polarski–Linder (CPL) parametrizations of the equation of state of the effective perfect fluid from the backreaction effect. Thanks to the effective geometry introduced by Larena et al. [Phys. Rev. D 79, 083011 (2009)] in their previous work, we confront such backreaction model with the latest type Ia supernova and Hubble parameter observations, coming out with the results that reveal the difference between the Friedmann–Lemaître–Robertson–Walker model and backreaction model.

Download Full-text