ULTRA-STRIPPED SNE
AND DOUBLE NEUTRON STAR SYSTEMS
Thomas Tauris, Norbert Langer, Philipp Podsiadlowski (2015)
MNRAS, accepted (arXiv: 1505.00270)
BONN VII. NS workshop, May 18, 2015
Ultra-stripped SNe
 Double NS systems
H
env.
NS
Ultra-stripping / recycling
LIGO
Ultra-stripped SNe
 Double NS systems
70 systems BEC
Porb,i = 0.06120 days
MHe,i = 2.510 Msun
stripping
He
O,
O,
Ne, C
Si,
S Mg
Fe
Ultra-stripped SN
Chemical composition
~10 year prior to SN
(Fe CCSN)
Chandrasekhar
mass limit
NS
Tauris et al. (2013)
He  C,O
C  Ne,Mg
M=0.1 Msun
 weak, fast decaying
SN light curve
O  Si
4
Ultra-stripped SNe: light curves
light diffusion time through the SN:
time when the electron scattering
optical depth of SN light curve = 1:
Peak brightness (Arnett’s rule 1979;1982)
MNi /Msun
0.001
0.005
0.01
0.05
M (abs mag)
-11.8
-13.4
-15.0
-16.6
BONN VII NS, May.18, 2015
Thomas Tauris - Bonn Uni. / MPIfR
M=0.01-0.2 Msun
weak, fast decaying
SN light curve
5
Ultra-stripped SNe
 Pre-SN cross-sections
If SN mass cut is here…
Ebind
Lattimer & Yahil (1989)
M NS  1.10  1.80 M
Porb,i = 0.1 days
M He,i = 2.5  6.0 M
7
= ultra-stripped EC / Fe CCSN
candidates
Double Neutron Star Systems
P (ms)
Porb (d)
ecc
Mpsr / Mcomp
Mtotal
0.19
4.07
0.11
1.61 / 1.17
2.78
0.10
0.09
1.34
1.25
2.59
recycled
J0453+1559
recycled
young
J0737-3039 A
B
recycled
J1518+4904
40.9
0.022
8.63
0.25
?/?
2.72
recycled
B1534+12
37.9
2.4
0.42
0.27
1.33 / 1.35
2.68
recycled
J1753-2240
95.1
0.79
13.64
0.30
?
?
9.70
0.09
? / >0.40
?
young
J1755-25? Cherry
45.8
Pdot (10-18)
22.7
2773.5
315.2
1.8
892
2470
recycled
J1756-2251
28.5
1.0
0.32
0.18
1.34 / 1.23
2.57
recycled
J1811-1736
104.2
0.90
18.78
0.83
<1.64 / >0.93
2.60
recycled
J1829+2456
41.0
0.053
1.18
0.14
<1.38 / >1.22
2.59
young
J1906+0746
144.1
0.17
0.09
1.29 / 1.32
2.61
recycled
New PALFA
Lazarus et al.
20300
27.3
0.15
0.20
0.09
?
2.86
recycled
B1913+16
59.0
8.6
0.32
0.62
1.44 / 1.39
2.83
recycled
J1930-1852
185.5
18.0
45.06
0.40
<1.29/ >1.30
2.59
GC
J1807-2500B
4.2
8.2*
9.96
0.75
1.37 / 1.21
2.57
GC
B2127+11C
30.5
5.0
0.34
0.68
1.36 / 1.35
2.71
Bonn VII NS 2015
Thomas Tauris - Bonn Uni./MPIfR
13
Ultra-stripped SNe  NS with small kicks(?)
1) Small mass of ejected envelope  weak gravitational tug on proto-NS (e.g. Janka 2010, and refs.)
2) Small binding energy of the envelope  fast ejection (little time for anisotropies to build up)
But needs to be resolved with stellar evolution calculations until onset of collapse + explosion study.
larger kicks?
small kicks?
BONN VII NS, May.18, 2015
Thomas Tauris - Bonn Uni. / MPIfR
14
DNS
(Porb – Pspin) and (Porb – ecc) correlations
Porb   t X   M NS   Pspin 
Wide orbit:
@RLO little time
prior to explosion
BONN VII NS, May.18, 2015
Thomas Tauris - Bonn Uni. / MPIfR
15
DNS
(Porb – Pspin) and (Porb – ecc) correlations
Porb   t X   M NS   Pspin 
RLO
3.0 Msun
Porb,i = 50 days
carbon
shell burning
BONN VII NS, May.18, 2015
Thomas Tauris - Bonn Uni. / MPIfR
16
DNS
(Porb – Pspin) and (Porb – ecc) correlations
Porb   t X   M NS   Pspin 
BONN VII NS, May.18, 2015
Thomas Tauris - Bonn Uni. / MPIfR
17
DNS
(Porb – Pspin) and (Porb – ecc) correlations
MNS, acc (Tauris, Langer & Podsiadlowski 2015), xEdd = 2

Pspin (Tauris,
Langer & Kramer
2012)
…more
complicated
as such,
(Lazarus et al. 2014)
but in general
is reproduced nicely.
pre-SN:
M and obs.
Porb data
(Tauris, Langer & Podsiadlowski 2015)
mass cut @ CO core, Ebind (Lattimer & Yahil 1989)
symmetric SN
 post-SN Porb
MHe = 3.0 Msun
MNS = 1.35 Msun
Ramifications
– Ultra-stripped SNe and DNS systems
1) Ultra-stripped SNe are important for the formation of double NS systems
(small ejecta masses, possibility of small kicks, NS masses: 1.101.80 Msun).
2) All DNS LIGO sources in Galactic field have experienced ultra-stripped SNe.
3) Case BB RLO can explain (Porb,Pspin) and (Porb,ecc) correlations of DNS.
4) Ultra-stripped SNe can be electron capture or iron core-collapse SNe.
5) Ultra-stripped SNe are possibly already observed (SN 2005ek,
•
Tauris, Langer & Podsiadlowski (2015)
MNRAS, accepted, arXiv: 1505.00270
•
Tauris et al. (2013), ApJ Letters 778, L23
BONN VII NS, May.18, 2015
Thomas Tauris - Bonn Uni. / MPIfR
Drout et al. 2013).
73