CTIO PIA 2002 Student Project

Project Title:
K-Correction Calculation for Type Ia Supernovae

Advisor:
Nick Suntzeff

Introduction

What is a K-correction ?

Imagine that we will see a star far away from us and sudently they explode and it's become in a supernova and, if we are lucky, this supernova will be a Type Ia (whitout emission H lines). We will see the light of this supernova reddened so the goal of the K-correction try to "see" the supernova like it's own reference frame.

But a good K-corrction must include the atmosfera and the instruments distortion. For that we are working in synthetic photometry made whit standards stars...

The first step is calculate the zero point of the supernovae spectra in diferent bands ( UVBIR UX and BX) , UX and BX are filters whit the atmosferic absorption and this numbes are :

Table 1

\	UX	BX	B	V	R	I
Zp	-14.244	-15.3042	-15.2793	-14.850	-15.0551	-14.5573
RMS	0.0120	0.0095	0.0076	0.0020	0.0081	0.00118

also we calculated the zero point for Z filter: Zp(Z)= -12.732

The next step is to compare this zeropoints whit supernovae spectra template (only B V I )

Table 2

\	BX	B	V	I
RMS	0.0041	0.012	0.0068	0.0074

Then we simulate Kcorrection for three supernovae spectra: SN1990N, SN1991T and SN1992A, but correcting first, this supernovae by the heliocentric velocities of the host galaxies: 963(km/sec) for NGC4639 (SN1990N), 1730(km/sec) for NGC4527 (SN1991T) and 1809(km/sec) for NGC1380 (SN1992A), following the Hamuy et al. recipe.

Pictures galery

Back to the 2002 CTIO REU/PIA Program page...

Other links

Departamento de Astronomía y Astrofísica PUC

Pamela's pictures galery

Simulador, an argentinean friends band