1. The most powerful explosions in the Universe
EWASS 2012, Symposium 10:
"30 years of Italian participation to ESO”
The most powerful explosions in the Universe
Genesis and evolution of Supernova and
Gamma-Ray Burst Italian programs at ESO 
Elena Pian - INAF, Trieste Astronomical Observatory

2. Supernovae
The detection of SN1987A boosted the Supernova research at ESO
In the 1990s, the ESO programs led by the Supernova group in Padova pioneered and developed the concept of Target-of-Opportunity on “unpredictable” sources

3. Absolute light curves of 87 SN Ia
Diversity of SNIa
Absolute light curves of 87 SN Ia
m15(B)
RTN per SNIa vicine
No STD candles !!

4. Normal SNe Ia follow Phillips relation!
Pskovskii – Phillips relation
normal
To me normal SNIa are those Sne that follow the Phillips relation (Bob already introduce this important relation when using SNIa as cosmological lighthouses)
Altavilla et al

5. Photospheric velocities of SN Ia
13/09/2018
Si II 6355Å velocity evolution v .
HVG 97 km/s/d
LVG 37 km/s/d
FAINT 87km/s/d
≈MB
≈MB+2
So, by we were able to update David’s plot with well followed nearby Ia. As you can see, the main feature of a big dispersion in the exp. Velocity is still there, but now we may characterize different behaviors. In particular, we may note that the velocity evolution followed by the different Sne post maximum is more or less linear and may be fitted with a straight line. If we define as velocity gradient the slope of this line, we may divide our Ia sample, using this new paramater. HVG are then those Sne with higher velocity gradient, high expansion velocities and bigger velocity spread. While the LVG have lower velocity gradient, slower expansion velocity which has a smaller dispersion. The Faint one have velocity gradients similar to HVG, but have much slower exp velocities and most of all they are much less luminous then HVG+LVG by about 2 mag
there seems to be at least two groups of SNIa: the green one with an low spread in the postmax velocity and post max slower velocity evolution. And the other SNIa with a big spread in velocity and much higher velocity evolution!
Colors are coded originally as the line blueshift of lines of the given SN, but finally as gradient
Green are more homogeneous !! SiII does not go slower than 9000 km/s
Blue the SiII extends well inside
No early data for Red
Benetti et al

6. Velocity gradient vs. Δm15
HVG
Faint
The new three Ia classes can be better seen in this plot. The Ia that are more photometric similar (HVG-LVG, same Dm15) have more kinematic differences in terms of velocity gradient and expansion velocities, while faint have vel grad similar to HVG but much lower expansion velocities and luminosity (higher Dm15)
LVG
Benetti et al

7. orro diagram! Applying density structure of W7
13/09/2018
X M (NSE+IME)
M (NSE)
M (56Ni)
M (54Fe + 58Ni)
Applying density structure of W7
transform vexp(Si) in mass.
By adding it to the NSE mass,
we obtain a constant mass,
1.05±0.09 Msun , with NO
Dependence on m15(B)
SNe that produce less 56Ni
Synthesize more IME
~0.09Msol
Using the maximum expansion velocity of Si at the moment of the explosion and applying the W7 density structure we are able to transform velocity of Si at the moment of the explosion in the mass enclose by the Si layer. This mass is, then, the amount of mass which has been processed by the thermonuclear explosion. Then with the modeling the nebular spectra we have derived the amount of Fe produced in the explosion. The difference gives the amount of IME produced in the explosion!!! Then you see that Sne which produced a lot of Fe have synthesized less IME, and vice-versa.
It deals with SNIa diversity, both from spect. and phot. point of view
Normal here is intended ot only Branch normal but also 91T and 91bg !!! 00cx and 02cx not included!
~0.13Msol
Mazzali et al

8. Gamma-Ray Bursts 28 February 1997:
BeppoSAX starts localizing GRBs with arcminute accuracy: the “GRB afterglow era” has started
~100 keV
About 250 GRBs have been followed up with ESO telescopes

9. GRB970228: first detection of X-ray and optical afterglow
NTT + SUSI, 13 March 1997
T hours T0 + 8 days
Van Paradijs et al. and the BeppoSAX
team 1997
T hours T0 + 3 days
BeppoSAX detection of X-ray afterglow
Costa et al 1997

10. GRB990510 (z = 1.6): optical afterglow
Lin. Pol. 1.7±0.2%
VLT+FORS
ESO NTT and 3.6m
The time decay is not a single power-law
Israel et al. 1999
Covino et al. 1999

11. The optically brightest GRB
(z = 0.937)
(z = 6.29)
(z = 1.6)
Bloom et al. 2009

12. GRB080319B: the robotic approach
REM+TORTORA
Racusin et al. 2008

13. GRB080319B: VLT in Rapid Response Mode with UVES
Fe II λ2374
Fe II λ2396*
z = 0.937
Detection of variable absorption lines and identification of 6 absorbers in a velocity range of 100 km/s
D’Elia et al. 2009

14. Metallicity of GRB host galaxies
VLT+X-shooter
Piranomonte et al. 2011

15. 25 April 1998:
Gamma-Ray Bursts meet Supernovae

16. GRB980425 Supernova 1998bw (Type Ic) z = 0.0085
Kinetic energy ~e52 erg

17. Light Curves of GRB and XRF Supernovae at z < 0.3
Pian et al. 2006
Bufano et al. 2012
Melandri et al. 2012

18. Photospheric velocities of Type Ic SNe
Pian et al. 2006
Bufano et al. 2012

19. Summary
A constant burned mass and a common explosion mechanism for Type Ia Supernovae: This may help in understanding their role as standard candles
GRB optical flashes and afterglows: Study of physics (photometry and multiwavelength comparison) and environments (spectroscopy)
GRB and XRF Supernovae: highly energetic Type Ic SNe.
GRB SNe are more luminous than XRF SNe. Is this telling us something about progenitors and remnants?

20. The Future NTT Supernova Large Program PI: S. Benetti
Public ESO Spectroscopic Survey for Transient Objects (PESSTO)
PI: S. Smartt, important Italian role with S. Benetti and S. Valenti
VLT FORS Type Ib/c and IIb Supernova program (late phase)
PI: P. Mazzali
VLT X-Shooter GTO TOO program (Denmark, France, Italy The Netherlands)
PI: J. Fynbo, Italian Co-PI: S. Covino
VLT X-Shooter GTO program on GRB host galaxies
PI: S. Piranomonte
VLT FORS GRB and X-ray Flash Supernova program
PI: E. Pian and M. Della Valle