Query on Cosmic Dark Energy by Error Analyses of Type Ia Supernova. Qiu-he Peng (Depart. of Astronomy, Nanjing University). § I Question of “Cosmic Dark Energy”. Origin of the Question of “Cosmic Dark Energy ”. “ Cosmic Dark Energy ” ← “ Acceleration of the Universe ”
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Qiu-he Peng
(Depart. of Astronomy, Nanjing University)
“Cosmic Dark Energy”←“Acceleration of the Universe”
←Observation of remote SNIa with z > 0.5
+ Taking SNIa as a Standard Candle Power (Assumption)
← Standard Picture of SNIa Explosion : SNIa Explode when
Mass of Accreting White Dwarf (in binary system) reaches at Chandrashkar critical mass
Ye :fraction of electrons
Light Curves and spectrums are similar for almost all SNIa
Mmax(- 18m) – ( -20m); Mmax= -2.5 log10 L
It seems is very close. It may be take as a standard candle at the maximum luminosity of SNIa
M= m + 5 – 5log D(pc) – A + K
A: interstellar extinction ;
K: correct by redshift of galaxies
The distance of SNIa may be determined by measuring its apparent luminance (m) when M is given
m – M +A – K = …… “distance modulus ” ( = 5log D(pc) – 5)
Phillips (1993) suggests a semi-experience relation by observation
Δm15:decrease in apparent luminance during 15 days after the maximum luminance
First, For some given SNIa with low redshift which their distances are given by another way of distance determination(e.g. by observation of cepheid variables ), we may get their Mmax by observations of their apparent luminance (m) at the moment of maximum brightness.
We may get the two parameters (a, b) through statistics by Mmax and observations of Δm15 .
Then, We may caculateMmax by measuring Δm15 for the remote SNIa
From the formula above.
But, This is only an assumption no any reason on theory.
i.e. No physics.
Advanced Phillips Way (1996 – 2007) :
They are based on two assumptions:
a) luminosity is related with the width of the light curve of SNIa;
b) luminosity is related with the color index (B-V) in the course of
explosion SNIa
It is a very complicated statistical relation.
SALT2 (Guy, J. et al., 2007) Software to deal with observational data of SNIa
The spectral energy distribution of light curve for SNIa:
F(SN, p, λ)= x0[M0(p, λ) + x1M1(p, λ) + ...] exp{cCL(λ)}
P: time(day) from the maximum moment in B wave band at the rest
reference system.
M0(p,): a function of spectral evolution with time in average for SNIa
Mk(p,): (k>0) Describing variance of other factors
X1: describing the width of the light curve for SNIa
CL(λ): corresponding to a color correction function in average
c = (B -V )MAX -< B -V > : variance of color index
Mk(p,) andCL(λ)describing the global behavior of SNIa
c , xi : parameters of each SNIa
Distance modulus of the SNIa
2. The total mass of the remnant of SNIa Tych(1572)
mSNR >1.8 mSun
rather than mSNR <1.4 mSun (Chandrashkar critical mass )
→ “Standard Picture of SNIa Explosion” is rejected.
→ The physical basis of both Philips relation and
advanced Philips way are lost.
The Standard candle of SNIa is only an assumption on theory without physical basis .
i.e. No physics.
It is shown that material distribution in some remnant of SNIa are obviously asymmetry in space direction by observation. (Kasen D., 2010, Nature, 466,37-38).It is also confirmed by simulation: (Maeda K. et al., 2010, Nature, 466, 82-85)
It is shown that the visual brightness of SNIa depends on the direction of observer. Then the Phillips’ (and advanced Phillips’) mathord is unphysical.
both Philips relation and advanced Philips way are
Assumptions or they are mathematic models without physical basis only.
The Set of SNIa after deal with by SALT2(software)
is just a set of “modeling SNIa” ,
rather than real set of SNIa.
There are some serious flaws in the error statistics for all previous researches:
However, the based assumption of standard candle power of SNIa has been negated by progress of researches on SNIa recent years.
Besides, Some serious flaws are in the error analysis of those papers:
2 The set of modeling SNIa in their papers (Amanullah, R., et al.(2010) (including685 SNIa) is really noGaussian distribution .
it is incorrect to find the intrinsic error of SNIa by 2 check test method.
Complete date（interval per 0.2mag）