1. Astronomy session: a summary
R. Coniglione,
INFN - Laboratori Nazionali del Sud

2. Astronomy session
Detector optimization: Kooijman for De Jong, Sapienza
FoM for Galactic sources: Sapienza, Coniglione, Leisos
The reference detector: 2 blocks of 310 strings (20 floors/string 40m distant) with MultiPMT. Distance between strings 100m. Total volume 3.8 km3
MC inputs: same (WPD document)
Codes: Sirene, HOU software, ANTARES code modified for KM3NeT (LNS code)

3. P. Kooijman for M. de Jong
Sirene
Sirene is yet another program that simulates the detector response to muons and showers
It uses a general purpose collections framework for PDF/CDF tables
allows for optimisation of accuracy and speed of interpolations
facilitates I/O
It runs about 10 x faster than km3
NO reconstruction – no search analysis
Analysis at trigger level
number of events with ≥ 5 L1s from RXJ1713 per year (Kelner spectrum)
L1 corresponds to two (or more) hits on same optical module within 10 ns
procedure
scaling factor applied to absorption length (0.9, 1.0, 1.1, 1.2)
vary horizontal spacing 80‒130 m and vertical spacing 30‒50 m
determine optimal spacing for each absorption length
dependence of performance figure on scaling factor

4. Module = Building block = smallest detector with optimal efficiency
P. Kooijman for M. de Jong
Scaling Factor: Absorption length wrt Km3 “standard” absorption length
Number of lines  In a block events scaled to 640 lines (20 floors)
Number of floors  Reduced floors gives more lines, 120 line blocks
scaling factor
scaling factor
events / year =
number of lines in a block
number of floors
Building block = smallest detector with optimal efficiency
80<Lines<120 and 15<floors<19

5. Example There is a clear maximum
P. Kooijman for M. de Jong
Example
events / year
horizontal spacing [m]
scaling factor 1.1
vertical spacing [m]
vertical spacing
horizontal spacing
There is a clear maximum
For this scaling factor: 100m horizontal and m vertical

6. Dependence on absorption length
P. Kooijman for M. de Jong
Dependence on absorption length
optimal detector
events / year
scaling factor
For each absorption length optimize the detector There is a clear linear dependence

7. From detector optimization with SIRENE
P. Kooijman for M. de Jong
Conclusions
From detector optimization with SIRENE
Typical numbers:
Blocks: lines
Floors:
Horizontal distance: m
Vertical distance: m
Numbers vary within these limits for different absorption length
Optimizing at each absorption length yields a linear dependence of number of events on absorption length.

8. P. Sapienza
The SNR RXJ1713
RXJ1713
Event simulation performed with Antares code adapted for km3 detector
Simulation for RXJ1713 with a Kelner spectrum in a flat disk of 0.6°
RECO => Fit with a scanning procedure based on a 3°x3° grid plus rotations + Aart strategy
Binned and unbinned search analysis
values of FoM (years for 5s discovery) and sensitivity

9. RXJ1713-39.46 sensitivity 1 y – DU distance
P. Sapienza
RXJ sensitivity 1 y – DU distance
Two blocks of 310 strings
20 multi-PMT/string
40 m distance between multi-PMT
Better performance for a 100m string distant detector
In one year, if no statistically significant excess will be found, upper limits lower the kelner model can be set
Proposed as public plot

10. P. Sapienza
RXJ s – DU distance
Official result to quote:
RXJ years preliminary and binned
Proposed as public plot
Binned
Significance
Years
Nsource
Nbackground
5sigma
5.8
29.9
26.8
3sigma
2.1
10.1
8.5
Unbinned estimated
100 m is a good distance for galactic sources
Unbinned calculations provide a rather good improvement of the FoM

11. RXJ1713-39.46 labs dependence L*abs = 1.1 Labs L*abs = 1 Labs
P. Sapienza
RXJ labs dependence
L*abs = 1.1 Labs
String Distance (m)
Nsource/year
Nback/year
F.O.M. 90
5.30
37.2 6.
100
5.40
34.2
5.6
130
5.10
24.1 6
10% difference in Labs-> Difference of about 5% between FOM
Same string distance optimization at different Labs
L*abs = 1 Labs
String distance (m)
Nsource/year
Nback/year
F.O.M. 90
5.01
34.4
6.3
100
5.04
30.0
5.8
130
4.66
20.9
6.5
Nsource and Nback = number of events in 1° around the source position (no cut applied)

12. From A. Leisos
HOU codes
Unbinned search method
The unbinned analysis and ANTARES code simulation gives 4.8y (estimated value)
Agreement at about 10%

13. The Pulsar Wind Nebula Vela X
R. Coniglione
The Pulsar Wind Nebula Vela X

14. VelaX Gamma spectrum R. Coniglione d=-45.6° Extension:
New HESS paper appeared on ArXiv in October 2012 and now on Astronomy and Astrophysics 548 (2012) A38 with a higher flux measurement. (53h 2012/ 12h 2006 of observation)
Observation up to 50 TeV
d=-45.6°
Extension:
Inner region 0.8°
Total 1.2°

15. Gamma spectra R. Coniglione N (GeV-1s-1cm-2) G Ecut (TeV)
F>1TeV (s-1cm-2)
RXJ1713
2.04
17.9
VelaX 2006*
1.45
13.8
VelaX 2012 total
1.32
14.0
VelaX 2012 inner
1.36
13.9
* F. Aharonian et al.,
Astronomy & Astrophysics L (2006)

16. R. Coniglione
Neutrino spectra

17. Simulation results Years for discovery 5s 50% 3s 50% 7.5 2.6 5.2 1.8
R. Coniglione
Simulation results
Source at d=-45.6° with a flat disk distribution of 0.8° (inner part of VelaX)
Reconstruction with scanning 3°x3°
no morphology in simulation
no atmospheric muons
Official value for public :
VelaX about 3 years preliminary
Years for discovery
5s 50%
3s 50%
Vela X 2006 Kappes
7.5
2.6
VelaX 2006 Vissani
5.2
1.8
VelaX 2012 inner Vissani
2.8
1.1

18. A. Leisos
HOU codes
Unbinned search method
3.8 years with HOU codes to be compared with 2.8 years with ANTARES code and binned analysis
Difference to be investigated.

19. The SuperNova Remnant Vela junior
R. Coniglione
The SuperNova Remnant Vela junior

20. Vela Junior gamma spectrum
SNR Vela Junior d=-46.37°
F. Aharonian et al., Astrophys. Journal (2007) 236
data from December 2004 to May 2005 (33h of ON-source run)
Observation up to ≈20 TeV
no cut off observed
Radial profile
G=2.24 N=

21. Vela Junior gamma spectrum
SNR Vela Junior d=-46.37°
Manuel Paz Arribas et al., ICRC 2011
Amount of data increased by a factor 2
data from 2004 to 2009 (72h of live time after data quality selection)
Morphology analysis -> NO absolute flux values ->
*N extracted from 2007 values N
(GeV-1s-1cm-2) G
Ecut
(TeV)
F>1TeV (s-1cm-2)
VelaJ 2007 *
2.24 -
VelaJ ICRC 2011 single region *
2.11
VelaJ ICRC 2011 whole *
2.22

22. Vela Junior neutrino spectrum* ** N
(GeV-1s-1cm-2) G
Ecut
(TeV)
F>1TeV (s-1cm-2)
VelaJ Vissani 2007**
2.24 -
VelaJ Vissani ICRC 2011 single region**
2.11
VelaJ Kappes*
1.72
1.19

23. Simulation results Vela Junior
Source at d=-46.37° with a flat disk distribution of 1°
Reconstruction with scanning 3°x3°
no morphology
no atmospheric muons
Years for discovery
5s 50%
Vela Junior Vissani 2007
>10
VelaJ Vissani ICRC 2011
2.9
+ cutoff 13 TeV 6
VelaJ Kappes
>>10
No cutoff unrealistic
With a supposed cutoff (not measured)

24. The Fermi bubbles

25. The Fermi bubble To be confirmed
In the paper simulation for 2 x154 towers with multiPMT 180m spaced (≈6km3)
Paper appeared in Astroparticle Physics Vol. 42 (feb 2013) 7-14.
tower+multipmt
Discovery for E-2 with a TeV spectrum in about 1 ÷1 ½ year
Discovery for E-2 with a TeV spectrum in about 5 ÷6 years
strings+multipmt
(no muatm)
Discovery for E-2 with a TeV spectrum in about 1 ÷1 ½ year
Discovery for E-2 with a TeV spectrum in about 3÷4 years
To be confirmed

26. Summary String distance optimization -> 100m
No different optimal string distance at different Labs
Discovery of RXJ1713 in about 5.8 years (agreement at about 10% with HOU results)
Discovery of VelaX in about 3 years (difference with HOU results to be understood)