Supernova Type Ia rates
for
SD and DD models
Silvia Toonen - [email protected]
Gijs Nelemans, Madelon Bours, Simon Portegies Zwart
Rasmus Voss, Christian Knigge
Joke Claeys, Nicki Mennekens, Ashley Ruiter
September 26th 2013
:
%:S
/A0"
&/
0)
8#/.#03/0
Previous Lorentz workshop
Are different results caused by accuracy or assumptions?
Solid: DD
,00.-
Dashed: SD
,.-
ref: Nelemans, Toonen, Bours 2013
:
%:S
/A0"
&/
0)
8#/.#03/0
Previous Lorentz workshop
Are different results caused by accuracy or assumptions?
Solid: DD
,00.-
Dashed: SD
using SeBa (Portegies Zwart & Verbunt 1996, Nelemans et al. 2001, Toonen et al. 2012)
,.-
ref: Nelemans, Toonen, Bours 2013
Single degenerate channel
✤
Predicted
rates differ
by a factor ≤
5000
Single degenerate channel
✤
Efficiency of mass accretion onto 1Msun white dwarf
stable burning
wind
novae
✤
Based on Nomoto et al. 2007, Hachisu et al
2008, references therein
✤
.
✤
.
Single degenerate channel
✤
Efficiency of mass accretion onto 1Msun white dwarf
✤
Based on Nomoto et al. 2007, Hachisu et al
2008, references therein
✤
As assumed in Ruiter et al. 2009
✤
.
Single degenerate channel
✤
Efficiency of mass accretion onto 1Msun white dwarf
✤
Based on Nomoto et al. 2007, Hachisu et al
2008, references therein
✤
As assumed in Ruiter et al. 2009
✤
As assumed in Yungelson 2010
Single degenerate channel
✤
Efficiency of mass accretion onto 1 Msun white dwarf
Single degenerate channel
✤
Efficiency of mass accretion onto white dwarf
ref: Bours, Toonen, Nelemans 2013, A&A
:
Previous Lorentz workshop
%:S
/A0"
&/
0)
8#/.#03/0
,00.-
Are different results caused by accuracy or assumptions?
,.-
Popcorn!
population synthesis comparison
ref: Toonen, Claeys, Mennekens, Ruiter 2013, submitted to A&A
Another application:
Mass transfer cycles
✤
Observational indications of mass transfer variability
✤
large range of mass transfer rates in CVs with similar properties
(Townsley & Gaensicke 2009, Patterson 2009)
✤
✤
Mass transfer rate of recurrent novae T Pyx is ‘too high’ for its
period (Patterson et al. 1998, Schaefer et al. 2010)
Important for:
✤
SNIa progenitors
✤
Cataclysmic variables
Mass transfer cycles
✤
If accretion rate is to be affected, the variability timescale should be:
✤
not too long: binary properties affected
✤
not too short: burning process not affected
➡ variability of the mass transfer rate of the donor to the disc
✤
change of radius star or Roche lobe radius
e.g. through irradiation-induced mass-transfer cycles (Podsiadlowski 1991;
Hameury et al. 1993, King et al. 1996, Buning & Ritter 2004)
Mass transfer cycles
✤
If accretion rate is to be affected, the variability timescale should be:
✤
not too long: binary properties affected
✤
not too short: burning process not affected
➡ variability of the mass transfer rate from the donor
✤
change of radius star or Roche lobe radius
e.g. through irradiation-induced mass-transfer cycles (Podsiadlowski 1991;
Hameury et al. 1993, King et al. 1996, Buning & Ritter 2004)
Toy model
✤
✤
On- and off-state with duty cycle α < 1
✤
Mass transfer rates in the on-state:
✤
α =0.1
model no variability, model CONST
Toy model
✤
✤
On- and off-state with duty cycle α < 1
✤
Mass transfer rates in the on-state:
✤
α =0.1
model no variability, model CONST, logNORM, logNORM_MAX
Toy model
✤
✤
On- and off-state with duty cycle α < 1
✤
Mass transfer rates in the on-state:
✤
α =0.1
✤
α =0.01
model no variability, model CONST, logNORM, logNORM_MAX
Mass transfer variability
✤
✤
Retention efficiencies for a 1.3Msun white dwarf
✤
α =0.1
✤
α =0.01
model no variability, model CONST, logNORM, logNORM_MAX
Application to SNIa rates
✤
Delay time distribution
ref: Toonen, Voss, Knigge to be submitted to MNRAS
Double degenerate channel
Common-envelope phase:
α-CE (Webbink 1984)
✤ based on energy balance
∆Ebind = α∆Eorb
γ-CE (Nelemans et al. 2000, van der Sluys et al
2006)
✤
based on angular momentum
balance
∆J
∆Mtot
=γ
J
Mtot
Double degenerate channel
✤
Link with observed double white dwarf population
✤
α-CE
γ-CE
Double degenerate channel
✤
Supernova Type Ia rate
Integrated rate (1e-4/Msun)
γ-CE
2.0
α-CE
3.3
Observations
Maoz et al. 2011
23±6
Double degenerate channel
✤
Supernova Type Ia rate
Integrated rate (1e-4/Msun)
γ-CE
2.0
α-CE
3.3
Observations
Maoz et al. 2011
23±6
Perrett et al. 2012
4.4-5.2 (6-10)
Maoz et al. 2012
13±1.5
Graur et al. 2012
4-12
ref: Toonen, Nelemans, Portegies Zwart 2012, A&A
Questions?