1. Preliminary estimates
SNe-Ia with JDEM:
Preliminary estimates
Massimo Della Valle & Pippus Mannucci
INAF-Napoli and ESO & INAF-Arcetri

3. Assumptions 2h of integration time, S/N =5 limiting (Vega) magnitudes:
J= 25.85
H= 24.53
I= 26.52
R= 27.16
No other filters were available.
1.2m  1.5m, 2h  ~ 1h (3000s)

4. Spectral Distribution Energy (Panagia 2003)

5. M_B = -19.46 +-0.56, Richardson et al. 2002).

7. Hold in check what we are doing……
Perlmutter et al. 1998
SN 1992A moved at z=0.8 after normalization to in the B band:
R=24.27
I= 23.26
SN1997ap
z=0.83
R = ± 0.09
I = ± 0.07

8. The apparent magnitudes as a function of the redshift are summarized in Fig. 1. Solid lines are limiting magnitudes for R (blue), I (green), J (magenta) and H (red). Dashed lines represents the DUNE thresholds *made* 1 mag brighter than reported above.
The reason for that is the need to follow-up the SN over days past max
(SN rest-frame), i.e. up to about 1 mag fainter than it. Then, it is obvious that the DUNE thresholds at S/N~5
should refer to the last photometric measurement in the SN lightcurve not to its maximum light (S/N ~ 20)

9. Assumptions 2h of integration time, S/N =5 limiting (Vega) magnitudes:
J= 25.85
H= 24.53
I= 26.52
R= 27.16
No other filters were available.
1.2m  1.5m, 2h  ~ 1h (3000s)

11. Cappellaro et al. 1997

12. SN rates SNe / yr deg^2 dz z
SN rates (Ia and II) from Cappellaro et al. 1999, Mannucci et al. 2005
SNe / yr deg^2 dz z

14. 700 SNe-Ia / yr deg2 SNe / yr deg 2
Giving a redshift threshold of 1.5, I have computed the number of SN explosions up to that redshift (SN rates from Cappellaro et al und
Mannucci et al. 2005). In fig. 2 you find the number of SNe/ deg2 yr. Black and magenta solid lines are CC and Ia respectively.
Dashed lines are the same counts after correction for dusty environments (MDVP 2007). Up to z ~ 1.5, we have about 600 SNe-Ia/deg2 yr.
Over 4yr mission, with a control time of, say, 0.5 yr, we should be able to detect ~ 1200 SNe-Ia, 70% of them between z ~ 1 and z ~ 1.5.

15. MDVP 2007

16. 700 SNe-Ia / yr deg2 dust 550 SNe-Ia / yr deg2 SNe / yr deg 2
Giving a redshift threshold of 1.5, I have computed the number of SN explosions up to that redshift (SN rates from Cappellaro et al und
Mannucci et al. 2005). In fig. 2 you find the number of SNe/ deg2 yr. Black and magenta solid lines are CC and Ia respectively.
Dashed lines are the same counts after correction for dusty environments (MDVP 2007). Up to z ~ 1.5, we have about 600 SNe-Ia/deg2 yr.
Over 4yr mission, with a control time of, say, 0.5 yr, we should be able to detect ~ 1200 SNe-Ia, 70% of them between z ~ 1 and z ~ 1.5.

17. Botticella et al. 2008
SNe-Ia / yr deg2

18. 700 SNe-Ia / yr deg2 dust 550 SNe-Ia / yr deg2
1000 SNe-Ia/yr deg2 up to z ~2
SNe / yr deg 2
Giving a redshift threshold of 1.5, I have computed the number of SN explosions up to that redshift (SN rates from Cappellaro et al und
Mannucci et al. 2005). In fig. 2 you find the number of SNe/ deg2 yr. Black and magenta solid lines are CC and Ia respectively.
Dashed lines are the same counts after correction for dusty environments (MDVP 2007). Up to z ~ 1.5, we have about 600 SNe-Ia/deg2 yr.
Over 4yr mission, with a control time of, say, 0.5 yr, we should be able to detect ~ 1200 SNe-Ia, 70% of them between z ~ 1 and z ~ 1.5.

20. ESO HAWK+VLT J=23.9 H=22.5 K=22.3 3600s and S/N=5
Solid lines represent the S/N=5 photometric thresholds for JDEM (magenta) and E-ELT (black, for 42m, Strehl=0.5, Encircled Energy
within 1.22 lambda/D=0.77). Dashed lines are spectroscopic thresholds for resolution R=100 (which is pretty low, but sufficient to make SN
spectroscopic classification).
The green spectrum is SN 1992A moved at z=2. Consistently with the results reported above, a SN-Ia is still detectable, in imaging, at z=2 (at S/N ~ 5), but
certainly too faint for spectroscopic observations, even at resolution ~ 100. For a threshold of ~ erg cm-2 s-1 A-1,
observations with resolution of ~100 are viable only up to z ~

21. z=1

22. Summary
The SN survey  in J band  range of redshifts of cosmological interest (up to z ~ 1.5). Survey in I (or R) bands are less deep (z~1-1.2).
The estimated number of detectable SNe-Ia, up to z~1.5 (after correction for dust) is ~ 550 SNe-Ia /yr deg2 ( ). After assuming a survey efficiency of ~ 0.5, the number of detected SNe-Ia over 4 deg2 and 2yr of mission turns out to be ~ 2200 SNe.
Spectroscopic observations from JDEM telescope.
The size of the mirror represents the major drawback. Low resolution observations R=100 (still sufficient to make SN classification) are viable for z ~1 (1h).
In principle SNe-Ia are detected up to z ~ 2 (1000/yr/deg2).
Are they useful? (EELT, JWST follow up? Photometric classification)
To do list: i) to carry out similar computations for II, Ib/c and HNe ii) to explore the possibility to observe SNe-Ia at near-IR wavelengths (rest frame)