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Forschungszentrum Karlsruhe in der Helmholtz-Gemeinschaft. Summary and Issues of. Workshop, Bad Liebenzell, Dec. 2003. Bianca Keilhauer. Tokyo, February 26th, 2004. Forschungszentrum Karlsruhe in der Helmholtz-Gemeinschaft. Bianca Keilhauer. Tokyo, February 26th, 2004.

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Forschungszentrum karlsruhe in der helmholtz gemeinschaft

Forschungszentrum Karlsruhein der Helmholtz-Gemeinschaft

Summary and Issues of

Workshop, Bad Liebenzell, Dec. 2003

Bianca Keilhauer

Tokyo, February 26th, 2004


Forschungszentrum karlsruhe in der helmholtz gemeinschaft

Forschungszentrum Karlsruhein der Helmholtz-Gemeinschaft

Bianca Keilhauer

Tokyo, February 26th, 2004

http://www.auger.de/events/air-light-03/

  • 4 interesting days in December 2003

  • 39 participants

  • 25 presentations

  • 10 projects

  • ⇒ improvements in understanding the aspects of molecular physics and in experimental measurements


Forschungszentrum karlsruhe in der helmholtz gemeinschaft

Bianca Keilhauer

Tokyo, February 26th, 2004

Fluorescence Light - starting theory -

Franck-Condon-Principle for absorption and fluorescence

A. N. Bunner: Cosmic Ray Detection by Atmospheric Fluorescence, PhD thesis 1967


Fluorescence from nitrogen

M. Nagano

Fluorescence from Nitrogen

N2

N2+

1st Negative band

2nd Positive band

Data from

Bunner (1964) : weighted averages of

three experiments with an accuracy of

not better than ±30%.

Kakimoto et al (1996) : 1.4MeV-1000MeV

are mainly used in UHECR experiments.


Forschungszentrum karlsruhe in der helmholtz gemeinschaft

M. Risse

Energy Spectrum


Forschungszentrum karlsruhe in der helmholtz gemeinschaft

R. Engel

E. Marques

Idea

The „classic“ method of determination of Ne (X) is subject to a purely geometrical correction due to the lateral spread of shower particles.

  • conventional approach:

Bianca Keilhauer

Tokyo, February 26th, 2004

Discussion on Fluorescence Yield of an EAS


Forschungszentrum karlsruhe in der helmholtz gemeinschaft

R. Engel

E. Marques

  • ionization energy approach:

Bianca Keilhauer

Tokyo, February 26th, 2004

Discussion on Fluorescence Yield of an EAS


Forschungszentrum karlsruhe in der helmholtz gemeinschaft

R. Engel

Ionization energy deposit: problems

  • Assumption

    • No clear experimental evidence

    • Precision of energy reconstruction will depend on fluorescence yield data

  • Angular spread and definition of track length dX

    • Track length along shower axis

    • Actual track length of particles

  • Energy loss in fluorescence yield experiments

    • Low energy ( E≪ Ec): ionization loss

    • High energy: ionization and radiative losses (small cascades)

    • Detailed simulation of ionization energy deposit needed

  • Calorimetric energy Ecal not equal to total shower energy


Dependencies

P. Colin

Dependencies

Excitation

Desexcitation

Measured dependencies today :only E, P and λ

Macfly project :PO2, PH2O, (T, nature)


Excitation processes

M. Fraga

Excitation processes

  • The C3Pu electronic state is a forbidden state; it cannot be directly excited by fast charged particles.

H. Brunet, PhD thesis, UPS,Toulouse,1973

Elim (C3Pu) = 11.03 eV

P.I. = 15.6 eV

W ~ 36 eV

Brunet PhD: http://www.auger.de/events/air-light-03/#phd_brunet


Forschungszentrum karlsruhe in der helmholtz gemeinschaft

B. Keilhauer

with

and

Fluorescence Light

  • EAS excites N2 molecules in air

  • 18 transitions in 2P system between 300 and 400 nm

  • 1 transition in 1N system between 300 and 400 nm

  • Calculation follows the principle way suggested by A. Bunner, 1967

⇒ quantum efficiency of fluorescence =


Forschungszentrum karlsruhe in der helmholtz gemeinschaft

B. Keilhauer

Fluorescence Efficiency

with p/p‘νfor air (79% N2 and 21% O2):


Forschungszentrum karlsruhe in der helmholtz gemeinschaft

B. Keilhauer

sum in the region 300 – 400 nm

337,1 nm ≙ ①

357,7 nm ≙②

391,4 nm ≙③

29,2%

fluorescence efficiency (photons/MeV)

23,3%

@ 0 km: ①+②+③= 65,7%

@ 20 km:

① +② + ③= 63,2%

10,7%

31,8%

25,3%

8,6%

height (km)

Fluorescence Efficiency Profiles


Electron impact cross sections for n 2 and o 2

M. Fraga

Electron impact cross sectionsfor N2 and O2

Qd

el.

exc-S

ion

ion

vib

vib

att

exc-T

rot

Dashed curves - excitations

Magboltz -CERN

Pitchford and Phelps,

MagBoltz


Forschungszentrum karlsruhe in der helmholtz gemeinschaft

Bianca Keilhauer

Tokyo, February 26th, 2004

Arqueros, Madrid, < 30 keV

Nagano, Fukui Univ.

Waldenmaier, AirLight

Gorodetzky, Paris

Colin, MacFly 1. phase

Fraga, LIP-Lisboa

Kemp, Campinas 1. phase

Privitera, AIRFLY, e±-beam at BTF, 50-750 MeV

Colin, MacFly 2. ph., e±/μ-beam at CERN 25-100 GeV

Reil, Flash, e--beam at SLAC 28 GeV

Kemp, 2. ph., e--beam at LNLS1.37 GeV

Ulrich, Munich, 12 keV

2. phase: medical acc. 5-12 MeV


Forschungszentrum karlsruhe in der helmholtz gemeinschaft

F. Arqueros

Nagano et al. Astroparticle Phys. (2003)

Photon yields vs Bethe-Bloch

FY seems to be proportional to dE/dx for E > 0.8 MeV.

dE/dx grows fast at low energies. Does this relationship hold at very low energy?


Forschungszentrum karlsruhe in der helmholtz gemeinschaft

F. Arqueros

Preliminary set-up: the collision chamber

F. Blanco and M. Ortiz

HV (0  – 30 kV )

Nd:YAG

vacuum pump

photodiode/trigger

collision chamber

gas inlet

PMT

Digital

Scope

vacuum pump

UV filter

Faraday cup or

scintillator

Electron beam features

  • Energy up to 30 KeV.

  • Pulse Rate = 1 – 20 Hz

  • Time width = 20 ns (limited by the laser / plasma).

  • Intensity up to 200 mA peak.

  • Beam diameter 2 mm.

    Some stability problems !!

  • Differential pumping (up to 100 mtorr)

  • 1 PMT ORIEL 77348 (single counting) + UV filter

  • Digital scope (1 ns)


Forschungszentrum karlsruhe in der helmholtz gemeinschaft

A. Ulrich

Bianca Keilhauer

Tokyo, February 26th, 2004

High-precision Measurements

of Experts for

„Particle beam induced light emission“

Energy deposition in the gas (1 bar Ar)

Parameters for low energy electron beam excitation:

Particle energy:typically 15 keV Foil:300 nm silicon nitride Gas:typically 0.1 to 2 bar Beam currentcw typ. 10 μA av. (0.15 W) or pulsed

Modelled using the „Casino“ Program

P. Drouin, A.R. Couture, R. Gauvin, P. Hovington, P. Horny, H. Demers, Univ. de Sherbrooke, Quebec, Canada (2002)


Forschungszentrum karlsruhe in der helmholtz gemeinschaft

A. Ulrich

Usage of the membranes: (principle)

Diagnostics and gas system:

Time resolved optical spectroscopy

Grating monochromators (f=30cm, 0.03 nm resolution 1.order)

Wavelength range ~30 nm to 700 nm

Time resolution ~10ns beam pulses, ~1ns electronic res.

Detectors VUV-PMT,VUV MCP and diode array

Sensitivity measurements: two WI-17G Lamps (OSRAM) and D2 arc-lamps (Cathodeon)

Gas pressure 0 to ~ 2 bar (foil: 10 bar)

Gas mixing system with hot-metal gas purifiers (rare gases)

Capacitive manometers (MKS Baratron)


Forschungszentrum karlsruhe in der helmholtz gemeinschaft

A. Ulrich

Assignment:

III. Preliminary results from air

Spectra:

Overview, 1 bar, ~12 keV electron beam excitation

High resolution spectrum:

Preliminary result. Needs to checked!


Forschungszentrum karlsruhe in der helmholtz gemeinschaft

Bianca Keilhauer

Tokyo, February 26th, 2004

Arqueros, Madrid, < 30 keV

Nagano, Fukui Univ.

Waldenmaier, AirLight

Gorodetzky, Paris

Colin, MacFly 1. phase

Fraga, LIP-Lisboa

Kemp, Campinas 1. phase

Privitera, AIRFLY, e±-beam at BTF, 50-750 MeV

Colin, MacFly 2. ph., e±/μ-beam at CERN 25-100 GeV

Reil, Flash, e--beam at SLAC 28 GeV

Kemp, 2. ph., e--beam at LNLS1.37 GeV

Ulrich, Munich, 12 keV

2. phase: medical acc. 5-12 MeV


Electron beam

M. Nagano

90Sr (28.8y)

β

90Y (64.1h)

β

2.28MeV

3.3MBq

90Zr

Electron beam

average 0.85MeV

0.02%

99.98%

1.75MeV


A and b of various bands

M. Nagano

A and B of various bands

⇒ For details: N. Sakaki --- right after this presentation


Forschungszentrum karlsruhe in der helmholtz gemeinschaft

T. Waldenmaier

AirLight Experiment

  • Goals

  • precise measurement of the ...

  • pressure dependence

  • temperature dependence

  • effect of water vapor

  • effect of oxygen and argon

    Filters [nm]: 317, 340, 360, 380, 394, 430, M-UG6


Forschungszentrum karlsruhe in der helmholtz gemeinschaft

S. Klepser

Effective Transmission Curves

→ „Effective Transmission Curve“ for every Filter can be averaged.

Interference Filters Theory

Rel. Error using 0°-Transmission > 20 %

Rel. Error using eff. Transmission < 7 %

→ CWL of filters should be 1-2 nm above the observed wavelength.


Forschungszentrum karlsruhe in der helmholtz gemeinschaft

G. Lefeuvre

Bench Diagram

Source holder

Gaz injection

Source : 90Sr

Fluorescence

zone

Focusing lens

Spectrometer

“integral”

PMT

(PMT #2)

Spectrometer PMT

(PMT #3)

Plastic scintillator

  • PMT #1below measures the 90Sr spectrum generates gates

  • PMT #2integral EUSO configuration [300- 400 nm] wavelength

  • PMT #3in spectrometer 1nm bandwidth

Probes (T, P)

Scintillator PMT

(PMT #1)


Macfly specificities

P. Colin

Macfly specificities

Event by event measurement:

Low electron density like in air shower.

  • Study of new dependencies :

  • Composition and contaminant (Macfly 1)

  • Mainly : O2 Percentage and Humidity

  • Shower Age (Macfly 2)

Key point:

Real electromagnetic shower study

Shower = Σ component electrons ??


Results primary scintillation of n 2

M. Fraga

Results : primary scintillation of N2

2nd pos. system

P = 105 Pa; T = 296 K; Dl = 9 nm

H. Brunet, PhD thesis, UPS, Toulouse, 1973; a (2.8 MeV)


Quenching by water vapor

M. Fraga

Quenching by water vapor:

0-0 band intensity decreases with increasing concentration of water vapor.

Atmospheric pressure was assumed.

Plans for the future

  • Measurement of band intensities of the 2nd positive system as a function of pressure and temperature;

  • Study of the role of water vapor on the light yields and on the emission spectra.

  • Participation in the tests at CERN in the SPS beam facility - proposal submitted by the Annecy group (Ref:MacFly-MEMO-01 of 11/24/2003)


Chamber configurations

E. Kemp

Chamber Configurations

  • Particle Beam

e-

  • Radioactive Source


Relative efficiency gas filling dry air n 2

E. Kemp

  • Yi = NE / NP

  • NE : coincidence excesses

  • NP : particle detector counting

  • i : gas type

Relative EfficiencyGas Filling: Dry Air → N2

YN2

YN2 / Yair= 5.1± 0.3

Kakimoto et al. , NIM 372A, 527 (1996)

~ 5.6

Yair


Forschungszentrum karlsruhe in der helmholtz gemeinschaft

Bianca Keilhauer

Tokyo, February 26th, 2004

Arqueros, Madrid, < 30 keV

Nagano, Fukui Univ.

Waldenmaier, AirLight

Gorodetzky, Paris

Colin, MacFly 1. phase

Fraga, LIP-Lisboa

Kemp, Campinas 1. phase

Privitera, AIRFLY, e±-beam at BTF, 50-750 MeV

Colin, MacFly 2. ph., e±/μ-beam at CERN 25-100 GeV

Reil, Flash, e--beam at SLAC 28 GeV

Kemp, 2. ph., e--beam at LNLS1.37 GeV

Ulrich, Munich, 12 keV

2. phase: medical acc. 5-12 MeV


Forschungszentrum karlsruhe in der helmholtz gemeinschaft

P. Privitera

Beam monitoring with the calorimeter

  • The calorimeter is used for absolute and relative beam intensity measurement (<1000 e-/bunch)

  • Calorimeter counts single electrons

  • pedest.

  • 1 e-

  • Time*24 (s)

  • 2 e-

  • 3 e-

  • 4 e-

  • ADC counts


Forschungszentrum karlsruhe in der helmholtz gemeinschaft

P. Privitera

Energy dependence of fluorescence yield

  • UG6 filter

  • The scan was performed several times with consistent results.

  • Preliminary

  • Np.e.(fluor.)

  • ADCcal x E/442

  • Limited by multiple scattering on 1.5 mm thick exit Al window. The scan went down to 50 MeV.

  • Positrons (493 MeV) gave same yield within 3%


Cern beam simulation

P. Colin

CERN Beam simulation

CERN-SPS-X5 : 50 GeV electron beam

Macfly2

Macfly1

Electrons

Positrons

100 e- of 50 GeV

Only 1 e- of 50 GeV


Forschungszentrum karlsruhe in der helmholtz gemeinschaft

K. Reil

⇒ For details: J.N. Matthews --- right after the coffee break


Forschungszentrum karlsruhe in der helmholtz gemeinschaft

Forschungszentrum Karlsruhein der Helmholtz-Gemeinschaft

Bianca Keilhauer

Tokyo, February 26th, 2004

  • Exchange of already existing theoretical knowledge

  • Exchange of practical solutions for experiment „everyday life“

  • Fruitful discussion, even during night in the cellar

  • Setup of an exchange platform on internet currently under construction

http://www.auger.de/events/air-light-03/


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