fabrizia canfora - unam€¦ · fabrizia canfora aera meeting 09/02/2017 7 aera ii german data set...

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


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 )]


Simulation studies

AERA full detector simulations including measured noise

RdSimulationObserver from Standard Application

zenith<55°

3196 events


[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


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


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


FD–RD Xmax comparison

correlation = 0.72


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


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


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


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


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 )


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


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


Absolute calibration (3)

North-south East-west

Average over all frequencies

U received (C0 ,U noise)


Stefan's results


What next

Standard quality cuts for RD events

Combination of the methods and the global fit

Xmax from the pulse shape


BACKUP


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

→


C0-4 2d LDF


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


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


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


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


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


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)

fabrizia canfora - unam€¦ · fabrizia canfora aera meeting 09/02/2017 7 aera ii german data set...

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