Titolo
Fabrizia Canfora
Radio Xmax
reconstruction
AERA Meeting09/02/2017
Fabrizia Canfora AERA meeting 09/02/2017 2
Outlook
Johannes Schulz PhD thesis (2016) Xmax from the 2d radio LDF →
Stefan Jansen PhD thesis (2016)
Xmax from the spectral index of the radio pulse →
Xmax measurements with AERA
Fabrizia Canfora AERA meeting 09/02/2017 3
AERA 2d LDF
Xmax
Dmax
Xmax
Dmax
footprint widthfootprint width
The width of the distribution σ is sensitive to Xmax
IRON-LIKE SHOWER
PROTON-LIKE SHOWER
u( r )=A⋅[exp (−( r+C1⋅e v x B− r core)2
σ2 )−C0⋅exp (−( r +C2⋅e v x B− r core)
2
(C3⋅exp(C4⋅σ))2 )]
Fabrizia Canfora AERA meeting 09/02/2017 4
Simulation studies
AERA full detector simulations including measured noise
RdSimulationObserver from Standard Application
zenith<55°
3196 events
Fabrizia Canfora AERA meeting 09/02/2017 5
[m]LDFσ0 50 100 150 200 250 300 350
[km
]m
axge
oD
0
2
4
6
8
10
12
14
/ ndf2χ 300.3 / 300Prob 0.4843p0 0.3292±3.084−p1 0.002244±0.06553
/ ndf2χ 300.3 / 300Prob 0.4843p0 0.3292±3.084−p1 0.002244±0.06553
Simulation studies (2)
Quality cuts
p0=-3.297 ± 0.002 km
Johannes
p1=0.0646 ± 0.0001
Δσ = √ (δfit
2 + (11.8 m)2)cuts
zenith angle < 55° 3196
geomagnetic angle >10° 3196
60 m < σ < 270 m 2623
P4∙10-4 2117
σ/σ< 40% 1882
number of stations ≥ 5 468
fit robustness 302
Fabrizia Canfora AERA meeting 09/02/2017 6
Simulation studies (3)
Quality cuts
Mean=-0.3 ± 1.7 g/cm2
Sigma=53.5 ± 1.7 g/cm2
Johannes
cutszenith angle < 55° 3196
geomagnetic angle >10° 3196
60 m < σ < 270 m 2623
P4∙10-4 2117
σ/σ< 40% 1882
number of stations ≥ 5 468
fit robustness 302
Atmospheric model US-Standard
Fabrizia Canfora AERA meeting 09/02/2017 7
AERA II German data set
RD-SD-FD multi-hybrid showers from June 2013 to December 2014
(m)LDFσ0 50 100 150 200 250 300 350
(km
)m
axge
oD
0
2
4
6
8
10
12
14
/ ndf2χ 300.3 / 300
Prob 0.4843
p0 0.3292±3.084−
p1 0.002244±0.06553
/ ndf2χ 300.3 / 300
Prob 0.4843
p0 0.3292±3.084−
p1 0.002244±0.06553
/ ndf2χ 16.74 / 13
Prob 0.2113
p0 1.632±3.211−
p1 0.01304±0.06313
/ ndf2χ 16.74 / 13
Prob 0.2113
p0 1.632±3.211−
p1 0.01304±0.06313
Simulations
AERA (german data)
RdObserver from Standard Application
Fabrizia Canfora AERA meeting 09/02/2017 8
FD–RD Xmax comparison
correlation = 0.72
Fabrizia Canfora AERA meeting 09/02/2017 9
Pulse shape analysis
d
Xmax
d1
d2
L
x1
x2
|t 2− t1|=1c|d1 n1−(d2 n2−L)|
Pulse length for an observer at distance d from the shower axis:
Larger path length difference results in a longer pulse recorder.
Single radio station sensitive to the shower development
Fabrizia Canfora AERA meeting 09/02/2017 10
Frequency spectrum 0.47 EeV proton at different distances d from the shower axis (CoREAS)
S(ν) = A ·10bν b = spectral index A = scale parameter
General shape of a frequency spectrum
Image from Stefan JansenPhD Thesis
Fabrizia Canfora AERA meeting 09/02/2017 11
Spectral index parametrization
d=150m
Simulations with a star-shaped antenna alignment in the shower reference frame
eV ≤ E ≤ eV
θ ≤ ○
Image from Stefan JansenPhD Thesis
Fabrizia Canfora AERA meeting 09/02/2017 12
rejected station
working stations within 6 standard deviations around themode of the distribution
Station monitoring Root mean square of time trace
averaged over 100 bins per day averaged over 2 days
Fabrizia Canfora AERA meeting 09/02/2017 13
Relative calibrationFrequency-dependent relative amplitude calibration using the background emission from the galaxy
RdChannelGalacticConstantGenerator
Assuming that all stations are exposed to the same frequency-dependent radio emission from the galaxy at any given instance of time
amplitude of a single station avarage amplitude of all stations
c i , v=1m ∑
k=1
m Ai(ν , t k)
A (ν , t k )
Fabrizia Canfora AERA meeting 09/02/2017 14
Absolute calibration
⟨Umodel⟩=⟨U received ⟩C0 Umeasured2
=U received2
+U noise2
North-South
East-West
North-South
Eeast-West
radio sky model measured
Amplitude spectrum of the radio sky model (LFMap) and the measured spectrum at LST = 17 h
Fabrizia Canfora AERA meeting 09/02/2017 15
Absolute calibration (2)
⟨Umeasured2
⟩=⟨U model
2 ⟩
C0
+⟨U noise2
⟩
North-South
East-West
Combined
⟨U noise , NS ⟩
⟨U noise , EW ⟩
C0=1.625 ± 0.006
= 42.5 ± 0.3 mV
= 41 ±20 mV
Fabrizia Canfora AERA meeting 09/02/2017 16
Absolute calibration (3)
North-south East-west
Average over all frequencies
U received (C0 ,U noise)
Fabrizia Canfora AERA meeting 09/02/2017 17
Stefan's results
Fabrizia Canfora AERA meeting 09/02/2017 18
What next
Standard quality cuts for RD events
Combination of the methods and the global fit
Xmax from the pulse shape
Fabrizia Canfora AERA meeting 09/02/2017 19
BACKUP
Fabrizia Canfora AERA meeting 09/02/2017 20
AERA 2d LDF
u( r )=A⋅[exp (−( r +C1⋅e v x B− r core)2
σ2 )−C0⋅exp (−( r +C2⋅e v x B− r core)
2
(C3⋅exp(C4⋅σ))2 )]
A amplitude
σ width of the distribution
position of the shower core C
0−4
rcore
zenith dependent simulation-based constants
→
Fabrizia Canfora AERA meeting 09/02/2017 21
C0-4 2d LDF
Fabrizia Canfora AERA meeting 09/02/2017 22
Simulations studies
[m]LDFσ0 50 100 150 200 250 300 350
[km
]m
axge
oD
0
2
4
6
8
10
12
14
/ ndf2χ 1568 / 300Prob 0p0 0.1597±3.079−p1 0.001198±0.06603
/ ndf2χ 1568 / 300Prob 0p0 0.1597±3.079−p1 0.001198±0.06603
Fabrizia Canfora AERA meeting 09/02/2017 23
Station monitoring
Axrms=√ 1n∑i=1
n
(x i− x)2n = samples in one trace xi = amplitude in the ADC counts of sample ix = average amplitude of the trace
c i , v=1m ∑
k=1
m Ai(ν , t k)
A (ν , t k )
n = samples in one trace xi = amplitude in the ADC counts of sample ix = average amplitude of the trace
Relative amplitude calibration constants
Fabrizia Canfora AERA meeting 09/02/2017 24
Observer angle
The observer angle is defines as the position of the antenna relative to the vxB axis in the shower plane
A
v x B
v x
v x
B
charge excess
geomagnetic
Fabrizia Canfora AERA meeting 09/02/2017 25
Event selectionsd and fd reconstruction → θ SD < 60°n(SNRquad > 15.5) ≥ 3 Ω SD < 7.0°
SNRpeak > 7.0β=abs(expmes < 25° (difference between the polariazation angle measured and expected ())
A
v x B
v x
v x
B
charge excess
geomagnetic
Polarization angle = angle between the total electric field and vxB axis
Fabrizia Canfora AERA meeting 09/02/2017 26
LFMap
Create maps of the radio sky in antenna temperature T a at any particular frequency interpolating measurements of the full radio sky at several frequencies
Radio sky at 60 MHz
Fabrizia Canfora AERA meeting 09/02/2017 27
Simulation studiesJohannes Schulz PhD Thesis
Mean=-0.3 ± 1.7 g/cm2
Sigma=53.5 ± 1.7 g/cm2
p0=-3.297 ± 0.002 p1=0.0646 ± 0.0001
Δσ = √ (δfit
2 + 11.352)
Top Related