# Presentation: 309786

## SN cla         ification 

- Massimo Turatto

## What means “classification”

- “basic cognitive process of arranging into categories in order to sort out and understand vast arrays”
- Classification of SNe means sorting out SNe according to physical parameters and involved processes (mass, ..., explosion mechanism, ...)

## How

- Using all available information:
- Spectral features & evolution (late time)
- Luminosity & light curves
- Interaction with CSM
- Location and parent population
- Precursor
- ...
-       γrays-Xray-UV-opt-IR-radio-neutrinos

## Early type assignment

- Spectroscopically: presence/absence of lines of characteristic ions
- Photometrically: luminosity and SED                            (lc & colors)
-      less precise (p<1) but optimal for statistical typing,e.g. high z (Poznanski et al. 2006)  [in absence of WF spectroscopic multiplexers on 8-10m tel]
-                Quick and dirty

**Notes:**
Often with “classification” we mean “early typing”,  i.e prompt assignation of a type for subsequent intensive obs campaign.

## Taxonomy 2003

- MT 2003

## The consolidated scenario

- Ia
- (m15)

- Mi<8M
- binary

- thermonuclear
- runaway

- II
- (Menv)

- 8M<Mi<40M

- core
- collapse

- Ib/c

- Mi>40M

- core
- collapse

-  SN-GRB

- (angular momentum)

## What is

- Turatto 2003

- Technicalities for observers
- Wrong audience
- Good literature: e.g. Filippenko (1997), Wheeler & Benetti (2000), Turatto (2003), ..

- new and challenging from my pov

## “Normal” CCSNe

## SN2006gy Ofek et al. 2007, Smith et al. 2007

- SNIIn (Harutyunyan 2006) (AGN)
- MV~-22, the brightest ever despite uncertain reddening (E(B-V)=0.7-1.2)
- Slow rise (70d) & broooad light curve Erad>1051 ergs, efficient conversion of KE to light or E source

## Light curve

- Smith et al. 2007

## Spectral evolution

- VHb(26/9)=VHa=<600(unres), 2500, 9600(?) km/s
-            VHa(24/11)=130km/s, 2400, 4000 km/s

## Results Smith et al. (2007)

- Interaction powered l.c. Mdot=0.5 M/yr     comparable η Car
-    ?? LX=1.65 x 1039 erg s-1 (Smith 2007, ≠Ofek 2007)
- Radioactively powered l.c. M(Ni)=22 M
-   Mpr > 40 M (not interacting SNIa)

## Explosion of a massive LBV (>100M) with a η-Car eruption 10yr before SN  ??
Pair-production SN (PPSN) ?? 

- Pair-production SN (PPSN) ??

- What it is ? Smith et al. (2007)

## Pair Production SNe (Scannapieco 2006, non rotating, metal poor)

- T(lc)~1yr
- Presence of H
- Vexp~ 5000 km/s
- M(Ni) up to 50 M
- Etot= 1051-1053 ergs
- M(max) bright (not as much)
- No compact remnant

## Explosion of a massive LBV (>100M) with a η-Car eruption 10yr before SN ??
Pair-production SN (PPSN) ??

- Pair-production SN (PPSN) ??

- What is it ? Smith et al. (2007)

- Late time observations will probe CSM vs PPSN
- Further consequences:
- Not all stars M>40M loose envelope
- Pop III stars

## SN2006jc

- Δd=0.1±0.3arcsec

## Blue pseudo-continuum (FeII due CSM interaction)
Broad (4000-9000 km/s) lines of IME
Narrow (2200km/s) HeI  He-rich CSM
Narrow (500 km/s) absorption HeI, OI, Ha emission (undisturbed CSM)

- Broad (4000-9000 km/s) lines of IME
- Narrow (2200km/s) HeI  He-rich CSM
- Narrow (500 km/s) absorption HeI, OI, Ha emission (undisturbed CSM)

- Pastorello et al. 2007

## Foley et al. 2007

- 2 continuum comp. (blue one due FeII lines as in SNIIn - fluorescence)
- He lines <4900A show P-Cyg profile (1000km/s, typical of WR stars)
- Redder He lines show broader component (2-3000km/s)
- Double peak HeI, bluer CaII IR  aspherical
- Similar to 1999cq and 2002ao

## SNIc with narrow HeI (SNIb-n)

- SNIc 1988L
- Matheson et al.2001

- 2006jc +35d

- Pastorello et al. 2007

## 
MR<-18.3 (EB-V=0.05)
Little color evolution
Similar to 1999cq & 2002ao
Drop after 50 days but strong rise in IR

- MR<-18.3 (EB-V=0.05)
- Little color evolution
- Similar to 1999cq & 2002ao
- Drop after 50 days but strong rise in IR

- Pastorello et al. 2007

## conclusions

- Strong intermediate width He emissions He rich CSM (like H in SNIIn)
- SNIc features  CO WR  M>40M progenitor   Blue He lines with P-Cyg typical of WR stars
- Pre-SN LBV-like outburst (M=-14.3) massive 60-100M progenitor 15-25M core BH
- Transition from LBV  WR still having LBV outbursts
- Binary or projection effects ?

## SN 2003fg (SNLS-03D3bb, Howell et al. 2006)

- SNIa at z=0.2440, s=1.13

**Notes:**
Discovered during the SN Legacy Survey

## 0.87 mag brighter than median (x 2.2) 
Low exp. Vel., vmax(SiII)=8000 km/s
Does not obey to the lc-width vs L (too bright)

- Low exp. Vel., vmax(SiII)=8000 km/s
- Does not obey to the lc-width vs L (too bright)

**SuperChandra** (Howell et al., Jeffery et al.2006):
- Arnett law MNi=1.3M  MWD>MCH
-                                               =2.1 M(IPE+IME)
- Increased binding energy  low vexp

**Challenge the use of SNIa for Cosmology **
**(though rare) **

## CSM Interacting SNIa

- Echelle spectroscopy <10-6 M/yr
- Radio (VLA, ATCA) <10-7 – 10-8 M/yr
- Late-time observations (no H, O, CaII)
-    M(H)<< than expected (Marietta et al. 2000)
- No clear X-Ray detection
- ... but for the 3σ detection of 2005ke

## No clear evidence of moderate 

- SN2005ke

- Immler et al. 2006

- 3σ Swift detection of 2005ke
-   Mdot ≤ 0.3x10-6 M/yr

- Chandra

- No clear evidence of moderate
- CSM interaction in SNIa

## SN 2002ic(Hamuy et al. 2003)

-   SiII & SII lines
-   Hα
-  first SNIa for which H has been unequivocally detected

- Need a strong, varying continuum at all epochs to:
- increase the flux
- reduce the contrast
- change the SED
- satisfactory fit
- CSM interacting SNIa

## Light curve

- Bright maximum + rebrightening@1m (cavity, Wood-Vasey et al. 2004)
- Slow late decline
- 2004aw(Ic) ≡ 1999br(Ia)                           [E(B-V)aw=0.85 E(B-V)br=0.35]

**Notes:**
2004aw  

## SNIc

- spread in L(max)
- reddening ??

- Hα ?

## Surprising? 2004aw misclassified as SNIa

- 2004aw:
- SiII(?) ok
- Blue side ok
- SNIa:
- SiII, SII ok
- Red side  ok

- Early spectra

- Benetti et al. (2006)

**Notes:**
Good fit with both SNIa and SNIc is not surprising since 2004aw was misclassified as SNIa

## 1 month later

- 2004aw:
- SED ok
- Flux ok
- Broad Hα base ok
- SNIa:
- Overall ok
- Broad Hα base off by 50A

- Benetti et al. (2006)

## Late timeCSM interaction dominated

- Late timeCSM interaction dominated

## Late timeCSM interaction dominated

- O,Mg typical of CCSNe
- FWHM(OI)=7200 km/s (Deng et al. 2004) comparable to 1998bw and 2004aw
- Models fail to reproduce MgI (e.g. Chugai et al. 2006)

**Notes:**
Hard to disentangle SN from CSM
Chugai et al. 2006 reproduced blue continuum with mixture of Fe-lines + Ca but NOT MgI

## Correspondence is remarkable if explosion date is:

- 20d before max for 2002ic
- coinciding with GRB for 1997cy (and 1999E)

**Notes:**
Date sono calcolate da GRB x 97cy e expected burst x 02ic (max-20d)

## Conclusions(Benetti et al. 2006)

- SN 2002ic  CSM interacting SNIc            natural explanation for the presence of dense, structured CSM
- Type Ia possible but need special WD configurations
- 1997cy and 1999E are hidden type Ic and possible GRB connection is revived

**Notes:**
Woosley Bloom 2006: highly rotation massive stars  massive core
At ignition of O surface explosions which expell solar masses of materail

## Another one

- SN 2005gj        (Aldering et al. 2006)
- Soon on the screens!

- 1991T

- if present, CSM interaction in SNIa
-  is only very strong

**Notes:**
Work in progress Benetti 2007

## Taxonomy 2007

**Notes:**
Consolidated SN types
Now available much info at late times
Small sifferences: SNIbc-pec  broad-lined SNIc
                                SNIIP with broad range of properties (Hamuy & Pastorello)
                                interacting SNIa (??)