Upload
phamque
View
222
Download
3
Embed Size (px)
Citation preview
Strong Declining UV Emission From A Newborn Type Ia Supernova
Yi Cao (Caltech)
2
3
4
5
(Courtesy of M. Sullivan)
6
(Courtesy of M. Sullivan)
7
UV Observations of SNe Ia
Days Since Explosion
Abs
olute
Mag
nitu
de
Abs
olute
Mag
nitu
de
(Milne et al. 2010; Brown et al. 2012a, 2012b)
8
(Courtesy of D. Kasen)
9
(Kasen 2010)
X-ray UV
10
Fast & Furious
[06:04] 1st obs.
[06:55] 2nd cand[06:45] 2nd obs.
[06:12] 1st cand [07:05] cand saved [09:04] Gemini-N obs.
[12:43] Gemini-N spec. reduced
[01:25] Swift obs.
April 2, 2015 April 3, 2015
11
iPTF14atg: Discovery
redshift: 0.021
(Cao et al. 2015 Nature)
12
iPTF14atg: Swift Lightcurve
(Cao et al. 2015 Nature)
11121314151617
uvw2 u
14151617181920
91011121314151617
uvm2 b
14151617181920
0 2 4 6 8 10 12 14 16 18
11121314151617
uvw1
0 2 4 6 8 10 12 14 16 18
v
14151617181920
DDys since explosion
Abs
olut
e 0
Dgni
tude
Abs
olut
e 0
Dgni
tude
UV Luminosity: 3e41 erg/sDays Since Explosion
Abs
olute
Mag
nitu
de
Abs
olute
Mag
nitu
de
13
iPTF14atg: Swift Lightcurve
(Cao et al. 2015 Nature)
11121314151617
uvw2 u
14151617181920
91011121314151617
uvm2 b
14151617181920
0 2 4 6 8 10 12 14 16 18
11121314151617
uvw1
0 2 4 6 8 10 12 14 16 18
v
14151617181920
DDys since explosion
Abs
olut
e 0
Dgni
tude
Abs
olut
e 0
Dgni
tude
Binary separation: 60 or 90 Rsun
14
1000 2000 3000 4000 5000 6000 7000 8000 9000WDvelengWh ()
0.0
0.5
1.0
1.5
2.0
2.5
)lux
Den
siWy
(ergs/s/cm
2/
)
1e16
iPTF14atg: Spectral Energy Distribution
(Cao et al. 2015 Nature)
Swift/UVOT
R-bandOptical Spec.
60 Rsun90 Rsun
Rest-Frame Wavelength
Flux
Den
sity F
_lam
bda
15
(Cao et al. 2015 Nature)
iPTF14atg: Optical Lightcurver-B
and A
bsolu
te M
agni
tude
Days Since Peak
16
iPTF14atg: Optical Spectra
4000 5000 6000 7000 8000 90005esW-)rame WaveOenJWh ()
6Fa
Oed
)Oux
+ 2
IIseW
0ay 6.96
0ay 15.96
0ay 24.46
-une 3.15
6i II C II 2 I6 II7i IICa II Ca II0J II
)e II/III
612002es@max
612002es@+1 weeN
4000 5000 6000 7000 8000 90002bserver-)rame WaveOenJWh ()
Rest-Frame Wavelength
Black: iPTF14atgGreen: SN2002es
During UV flare
About 10 days before maxAround maxAbout a week after max
(Cao et al. 2015 Nature)
17
3000 4000 5000 6000 7000 8000 9000 10000
2bserved WaveOengWh ()
0
1
2
3
4
5
6
7
8
F(ergss1cm
1)
1e11
iPTF14atg: Host GalaxyStellar Mass: a few times 1e10 Msun
No Star Formation
Observed Wavelength
18
(Olling et al. 2015 Nature)
19
Conclusion
An strong UV flare is seen in a Type Ia SN iPTF14atg.
The UV flare is consistent with the SN-companion interaction signature.
The observations of iPTF14atg together with other recent observations strongly suggest that SNe Ia have multiple origins.
Future UV observations will help determine the fraction of SNe Ia originating from the single-degenerate channel.