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Earth's atmosphere and cosmic rays
(the point of view of an atmospheric physicist).
Vincenzo Rizi([email protected])
Dipartimento di FisicaUniversità Degli Studi - L’Aquila -ItalyRossella Caruso, Aurelio Grillo, Marco Iarlori, Sergio Petrera, Dipartimento di Fisica Università Degli Studi - L’Aquila Italy,Laboratori Nazionali del Gran Sasso, Istituto Nazionale di Fisica Nucleare
First International Workshop on Air FluorescenceSalt Lake City Utah October 5-8, 2002
Summary
• Planetary atmosphere as a calorimeter: atmospheric parameters and nitrogen
fluorescence yield. • In particular, the effect of atmosphere parameterization and/or
local meteorological measurable parameters.
• Atmospheric transmission of fluorescence light and determination of energy release by UHECR.
• Role of the aerosol transmission• Estimation of aerosol transmission (with real data).• Advantages of Raman lidar in measuring the aerosol transmission.
Relevant for inversion of Lidar Raman data, see later!
~2x107 years
~3x103 years
accumulative
~6 years
Residence times Individual speciesTurbulent mixing dominant at low altitudes (<120km)
i.e., mixing ratios ~ constant with altitude
78.084%
20.946%
0.934%
Trace gases0.036%
Atmospheric models and their use in the estimation of air fluorescence yield and light transmission.
National Space Science Data CenterNASA Goddard Space Flight CenterGreenbelt, MD 20771, USA
Models of preference for specialized tropospheric/lower stratosphere work.
Homogeneous mixing Perfect gasHydrostatic equilibrium
Partial list of available models ...
U.S. Standard Atmosphere 1976NOAA/NASA/U.S.Air Force (<32km) ICAO standard atmospheresteady state atmosphere for moderate solar activity based on rocket and satellite data + perfect gas theory
parameters listed: atmospheric temperature, pressure, density, …in 1966 supplement 5 northern latitudes for summer and winter.
Availability: the Fortran code can be obtained from Public Domain Aeronautical software.
References:U.S. Standard Atmosphere, 1976, U.S. Government Printing Office, Washington, D.C., 1976.
Atmospheric Handbook 1984NOAA/National Geophysical Data Center (NGDC)compilation by V.E. Derr
parameters listed: atmospheric parameters for scattering … calculations
Availability: from NGDC via anonymous ftp.
References:V. E. Derr, Atmospheric Handbook: Atmospheric Data Tables Available on Computer Tape, World Data Center A forSolar-Terrestrial Physics, Report UAG-89, Boulder, Colorado, 1984.
COSPAR (Committee on Space Research) International Reference Atmosphere: CIRA 1986compilations (Fleming et al., 1988) of ground-based and satellite measurements (Oort, 1983, Labitzke et al., 1985)
parameters listed: temperature, pressure, densities ...monthly mean values … for the latitude range 80N to 80S
Availability: from NSSDC's anonymous FTP site
References:E. L. Fleming, et al., Monthly Mean Global Climatology of Temperature, Wind, Geopotential Height and Pressure for 0-120 km, NASA, Technical Memorandum 100697, Washington, D.C., 1988.A. H. Oort, Global Atmospheric Circulation Statistics 1958-1983, NASA, Professional Paper 14, 180 pp., Washington, D.C., 1983. K. Labitzke, J. J. Barnett, and B. Edwards (eds.), Middle Atmosphere Program, MAP Handbook, Volume 16, University of Illinois, Urbana,
1985.
How these “atmospheres” compare … parameters relevant for air fluorescence yield and light transmission?
1 0 1 0 0 1 0 0 0p re ssu re (m b )
0
5
1 0
1 5
2 0
2 5
3 0
a ltitu d e (k m )
U S S ta n d a rd A tm o sp h e rela titu d e 4 5 N
w in te r
su m m e r
0 2 0 4 0v a ria b . %
Seasonal variability
For a typical GAP site
2 0 0 2 2 0 2 4 0 2 6 0 2 8 0 3 0 0tem p e ra tu re (K )
0
5
1 0
1 5
2 0
2 5
3 0
a ltitu d e (k m )
U S s tan d a rd a tm o sp h e re
w in te r
su m m er
C IR A 1 9 8 6
m o n th ly m ean p ro file s
0 4 8v a ria b . %
Seasonal variability
1 E + 1 8 1 E + 1 9
a tm o sp h e ric n u m b e r d e n s ity (c m-3
)
0
5
1 0
1 5
2 0
2 5
3 0
a ltitu d e (k m )
U S s ta n d a rd a tm o sp h e re
w in te r
su m m e r
C IR A 1 9 8 6
m o n th ly m e a n p ro file s
4 8 1 2v a ria b . %
Seasonal variability
REAL DATA: Local atmospheric parameters recorded by means of balloon borne meteorological radiosoundings.
Dipartimento di FisicaUniversità Degli Studi - L’AquilaItaly
Vaisala radiosondes measure upperair temperature, humidity and pressure, and upper air windspeed and direction, as they rise to their maximum altitude of ~30 km.
JanF eb
Mar
A prM
ayJun Ju l
A ugSep
O ctN ov
D ec0
1
2
3
4
5
6
7
8
9
1 0n u m b er o f P T U so u n d in g s
m a y 20 0 0 - sep tem b er 2 0 0 2to ta l n u m b er o f so u n d ig s 5 1
L 'A q u ila , Ita ly , 4 2 .3 5 N , 1 3 .2 2 E , s ite e lev a tion 6 8 3 m a .s .l.
L’Aquila, Italy 42.35N, 13.22E, 683m a.s.l.
1 0 1 0 0 1 0 0 0p ressu re (m b a r)
5 0 0 0
1 0 0 0 0
1 5 0 0 0
2 0 0 0 0
2 5 0 0 0
3 0 0 0 0a ltitu d e (m )
sp rin g
su m m er
a u tu m n
w in te r
0 1 0 2 0v a riab . %
Seasonal variability
sensors systematicsSame
atmosphere of a typical
GAP site?!
2 0 0 2 1 0 2 2 0 2 3 0 2 4 0 2 5 0 2 6 0 2 7 0 2 8 0 2 9 0 3 0 0
tem p era tu re (K )
5 0 0 0
1 0 0 0 0
1 5 0 0 0
2 0 0 0 0
2 5 0 0 0
3 0 0 0 0a ltitu d e (m )
sp rin g
su m m er
au tu m n
w in te r
0 4 8v a riab . %
L’Aquila, Italy 42.35N, 13.22E, 683m a.s.l.
Seasonal variability
sensors systematics
Outlines - atmospheric models
below 20km mid-latitude seasonal variability pressure up to 20%temperature 28%density 48%
Outlines - meteorological observations
below 20km 42N (L’Aquila - Italy)seasonal variability+sensors systematics pressure 2 10% temperature 4 8%
Atmospheric local parameters variabilityand air fluorescence yield
Nitrogen fluorescence
A.N. Bunner, 1964.
Keilhauer, B. et al., Auger technical note GAP-20012-022
TNTNN
2
2
1
1
11
O-th approx.!
, Fluorescence Yield (photons per meter per electron)
AIR FL(uorescence) Y(ield) approachPaolo Privitera
N, Atmospheric number densityT, Atmospheric temperature’s, ’s, constants
T
T
N
N
Kakimoto et al., A measurement of the air fluorescence yield, Nucl. Instr. And Meth. A, 372, 527-533, 1996.Nagano, M. and A.A. Watson, Observations and implications of the UHECR, Rev. Of Modern Phys. 72, 2000
Approaches …to minimize the errors fromatmospheric parameters variability
Adiabatic model, combined with local ground temperature and pressure measurements. Martin, G., and J.A.J. Matthews,GAP 1999-037, 1999
Local balloon borne meteorological radiosoundings.Forschungszentrum Karlsruhe - Institut für KernphysikKeilhauer, B., et al., GAP 2002-022, 2002
and/or
Atmospheric transmission of fluorescence light.
3 0 0 4 0 0w av e len g th (n m )
tim e
s
AFD
CR
sIAFD(s)
Io(s)
z
CR cosmic rayAFD Auger Fluorescence DetectorT’s transmission functionss range; z altitude
T’s
AFD light measurements
AFD light measurementsIn a single pixel:
efficiency quantum PMT)(
efficiency ion transmissoptical AFD )(
AFDat intensity cefluorescen Spectral )(
bandwidth spectrum cefluorescenAir
pixel single AFDby measuredintensity )(
sight of line thealong range
)()()()(
QE
sI
sI
s
dQEsIsI
AFD
AFD
AFDby subtended angle solid
)scattering multiple (i.e., scorrectionorder high
ion transmissabsorption gas )(
ion transmissscattering aerosol )(
@ ion transmissscatteringmolecular )(
)sight of line AFD of angle elevation theis ,s(z
z altitude @intensity spectral cefluorescenair )(
41)()()()()(
d
f
sT
sT
sT
sin
sI
dfsTsTsTsIsI
abs
aer
mol
o
absaermolo
+air fluorescence yield Energy of CR
)()()()( sTsTsTsT absaermoltotal
s range along the line of sight
It can be easily estimated with sufficient precision …!?
The absorption can be neglected because of the FD optical transmission …!?
Total atmospheric transmission
...
T
T
E
E
shower
E: shower energyT: atmospheric transmission
High variability …direct measurements with Raman lidar ORstrong assumption ...
section cross gas absorbing th-i )(
h wavelengt @ , refraction ofindex , radius of
particle aerosol an of efficiency extinction Mie),,(
@ section cross total Rayleigh
densitynumber gas absorbing th-i
ondistributi size aerosol
density number molecular catmospheri
)()(σexp)(
),(),,(exp)(
)(exp)(
0
i
0 0
2
0
i
ext
mol
i
aer
mol
i
s iabsabsabs
s
aerextaer
s
molmolmol
abs
abs
mr
mrQ
n
n
n
dssnsT
dsrsnmrQrdrsT
dssnsT
Single scattering approx.!
Laser Telescope DAQ
backscattering (bcks.)
Laser wavelength
Anelastic bcks.Raman (N2, O2 ...)
Elastic bcks. molecular/Rayleigh & aerosol/Mie
LIDARThe lidar should/could measure the needed quantities.
Laser photons Back-scattered photons
Atmosphere
4)()()(
dzTringbackscattezTNzN downupo
oo
collected photons laser photonsAtmospheric attenuation:scattering and absorption
Scattering processes:Rayleigh-Mie scatteringRaman scattering Resonant scattering
solid angle subtendedby the receiver 1/z2
z is the altitude/range
Advantages of Raman lidar vs. Elastic lidar.
Elastic/Rayleigh Lidar signal
telescopeby the subtended angle solid
particle aerosol an of efficiency ringbackscatte Mie),,(
8
310
)(
55045.5)(
:section cross ringbackscatte aldifferenti Rayleigh)(
laser by the emitted photons of #
)()()(
4),(),,()()(
)()()()(
1228
4
0
2mol
o
d
mrQ
srcmnm
L
sTsTsT
drsnmrQrdrsn
sTsTsTLsL
obck
molo
mol
mol
o
absaermol
aerobckmol
absaermolo
oo
o
o
ooo
ooooo
upward travel
backscatteringdownward travel
Key features of Klett method.
ms
otot
tottoto
sCs
dsssT
sTd
ssTLsL
oo
oo
ooooo
)()(
)(exp)(
)(4
)()()(
Recasting thelidar equation
Solving for )(sT otot
ds
dsm
sLsL
ms
m
sLsL
sTs
s
s
n
n
n
tot n oo
o
oo
o
0 '
)()'(exp
2
)(
1
)()(exp
)(ln
Mandatory assumption!
Unknown!
Key features of Fernald method.
)()(
)(exp)(
)()(4
)()()()()(
ssLR
dsssT
sTsTd
sssTsTLsL
oo
oo
oooooooo
aeraer
s
o aeraer
aermolmolaeraermolo
),(),,()(0
2 rsnmrQrdrs aerobckaero
),(),,()(0
2 rsnmrQrdrs aeroextaero
)()()( sns molmolmoloo
Mandatory assumption!
Unknown!
The Lidar Ratio (LR) is the inverse of the back scattering phase function.
Solving for )(sT oaer
ds
dsdssLRsLsLRss
sLs
dssLRsLs
LR
sT
s
s
s
s
s
molnaernmol
nn
s
s
mol
aer
n n
oo
oo
o
n
oo
o
0''
22
2
''')'(3
82exp)''(''2
)()(
)(
')'(3
82exp)(
)(ln
See …: Scannin lidar based atmospheric monitoring for fluorescent detectors of cosmic showers, D. Veberič, A. Filipčič, M. Horvat, D. Zavrtanik, M. Zavrtanik, submitted, 2002.
Anelastic/Raman Lidar signal
)337.1nm @ sr106.4 :O ;sr105.3 :(N
species th-i the
of section cross ringbackscatte aldifferenti Raman)(
)1556 :O ;2331 :(N
species th-i theofshift Raman theis
)()()(
4)()(
)()()()(
1-2302
1-2302
12
12
Ramani
cmcm
cmcm
sTsTsT
dsn
sTsTsTLsL
i
iii
ooooioi
Raman
i
absaermol
i
absaermolo
upward travel
downward travel
backscattering
2
2
log
))(log(
))(log(log
N
o
aer
aer
zT
zT
kiN
o
42
2
2
2
2
1
Raman
)(
4)()(
)(log
1
1
)(log
Noo
No
N
o
sTd
snL
sL
sT
mol
No
kNo
aer
Key features of Raman method.
Assumption!
Unnecessary if Raman signals from O2 and N2
are measured!
Unknown!
Estimation of aerosol transmission with real data.
UV Raman Vertical lidar - Dipartimento di Fisica - Università Degli Studi - L’Aquilao=351nm; Raman=382nm (N2); September 2001 L’Aquila 42oN (rural site) 1/2 hour measurements
0 1 2 3 4 5 6 7 8 9 1 0a ltitu d e (k m )
0 .1
1
1 E + 1
1 E + 2
1 E + 3
1 E + 4
1 E + 5
1 E + 6
Phot
onco
unts
(a.
u.)
E la s tic
R am an
0 4E-6 8E-6
bcks coeff. (m-1sr-1 )
1.0
1.5
2.0
2.5
3.0
alti
tud
e (
km
)
0 4E-4 8E-4
ext. coeff. (m-1)
1.0
1.5
2.0
2.5
3.0
0 25 50 75 100lr (sr)
1.0
1.5
2.0
2.5
3.0
1st step from Raman N2; k=-1
2nd step from Elastic
Taer(z)
(ext. Coeff.)(bcks coeff.)
1 .0 1 .5 2 .0 2 .5 3 .0a ltitu d e (k m )
0 .7 0
0 .7 5
0 .8 0
0 .8 5
0 .9 0
0 .9 5
1 .0 0ae
roso
l tra
nsm
issi
on
Elastic
Raman
The aerosol transmission function retrieved from real lidar signals (at Univ. AQ)The continuous lines refer to the case in which only the elastic signal is used (the lidar ratio is assumed), the dashed lines with symbols show the transmission calculated using the Raman signal.
• best configuration Scanning Raman/Rayleigh-Mie lidar
• elastic lidar More infos on backscattering than extinction. For simple non-scanning lidar systemthe aerosol extinction profiles (i.e., transmission function)derived by inverting the elastic signal, and assuming the lidar ratio, might have large systematic errors.
• anelastic lidar reliable aerosol transmission with no assumptions. A combined Raman/Rayleigh-Mie lidar measures aerosol extinction and backscattering independently.
Outlines
Aerosol variability
data from RAMAN LIDAR L’Aquila - Italy (~42oN)
clear skyabove 1500m (virtual Auger FD site)
Lidar ratio (LR) seasonal & altitude variation.
2 0 4 0 6 0 8 0 1 0 0lid a r ra tio (s r )
1 5 0 0
1 7 5 0
2 0 0 0
2 2 5 0
2 5 0 0
2 7 5 0
3 0 0 0
altit
ude
(m)
L 'A q u ila , I ta ly c lea r sk y c o n d itio n s
au tu m n /w in te r
sp rin g /su m m er
(6 2 + /- 5 )sr(59 + /- 5 )sr
(49 + /- 4 )sr
0 .0 E + 0 1 .0 E -4 2 .0 E -4 3 .0 E -4
a e ro so l ex tin c tio n (m-1
)
1 5 0 0
1 7 5 0
2 0 0 0
2 2 5 0
2 5 0 0
2 7 5 0
3 0 0 0
altit
ude
(m)
L 'A q u ila , I ta ly c lea r sk y co n d itio n s
a u tu m n /w in te r
sp rin g /su m m e r
Aerosol extinction seasonal variation.
0 2 0 4 0 6 0a e ro so l a tte n u a tio n le n g th (k m )
1 5 0 0
1 7 5 0
2 0 0 0
2 2 5 0
2 5 0 0
2 7 5 0
3 0 0 0
altit
ude
(m)
L 'A q u ila , I ta ly c le a r sk y c o n d itio n s
a u tu m n /w in te r
sp rin g /su m m e r
Aerosol attenuation length seasonal variation.
0 .7 5 0 .8 0 0 .8 5 0 .9 0 0 .9 5 1 .0 0
a e ro so l re la tiv e tra n sm iss io n
1 5 0 0
1 7 5 0
2 0 0 0
2 2 5 0
2 5 0 0
2 7 5 0
3 0 0 0
altit
ude
(m)
L 'A q u ila , I ta ly c le a r sk y c o n d itio n s
a u tu m n /w in te r
sp rin g /su m m e r
Aerosol transmission seasonal variation.
Aerosol transmission seasonal variation.
0 .7 5 0 .8 0 0 .8 5 0 .9 0 0 .9 5 1 .0 0ae ro so l re la tiv e tra n sm iss io n
1 5 0 0
1 6 0 0
1 7 0 0
1 8 0 0
1 9 0 0
2 0 0 0
2 1 0 0
2 2 0 0
2 3 0 0
2 4 0 0
2 5 0 0
2 6 0 0
2 7 0 0
2 8 0 0
2 9 0 0
3 0 0 0al
titud
e (m
)w in te r
sp rin g
su m m e r
a u tu m n
L 'A q u ila , Ita ly m o n th ly m ean p ro filesc lea r sk y co n d ition s
0 1 E -4 2 E -4 3 E -4 4 E -4 5 E -4
a e ro so l e x tin c tio n @ 3 5 1 n m (m -1 )
1 .5
2 .0
2 .5
3 .0
altit
ude
(km
)
0 .8 0 .8 4 0 .8 8 0 .9 2 0 .9 6 1 1a e ro so l tra n sm iss io n @ 3 5 1 n m
1 .5
2 .0
2 .5
3 .0
S ta rt T im e
1 8 :2 0
1 8 :5 0
1 9 :2 0
1 9 :5 0
2 0 :2 0
2 0 :5 0
L 'A q u ila , I ta ly , a e ro so l-w a te r R am an lid a r F eb ru a ry 4 , 2 0 0 2 - s ix p ro file s fro m 1 8 :2 0 to 2 1 :2 0 L T
Aerosol extinction and transmission “day” variation.
Outlines - aerosol contribution to light transmission
Most of the aerosol in the planetary boundary layer (<3km a.s.l.) clear skyfrom ~ 1500m a.s.l.relative transmission mean value ~0.85seasonal variability up to 15% (3)“day” variability (over 3hours - night) ~6%
Status of Raman channel integration in Auger lidar.
o p tica l fib er
P M T # 1E la stic
P M T # 2R a m a n O 2
P M T # 3R a m a nN 2
N O s
N D sIF # 1
N D sIF # 2 IF # 3
N D s
B S # 1 B S # 2 B S # 3
L
Technical details of Raman lidar
L: field lensBS: beam splitterNO: notch filterND: neutral density filterIF: interference filterPMT: photomultiplier
ElasticRaman O2
Raman N2
telescope
laser
INFN Torino/Nova Gorica Polytechnic LIDAR
Pino TO
0 .9 0 .9 2 0 .9 4 0 .9 6 0 .9 8 1
a e ro so l re la tiv e tra n sm iss io n
1
2
3
4
5
6
altit
ude
a.s.
l. (k
m)
0 1 E -7 2 E -7 3 E -7 4 E -7 5 E -7 6 E -7
a e ro so l b a c k sca tte rin g @ 3 5 5 n m (m -1 sr-1 )
1
2
3
4
5
6
altit
ude
a.s.
l. (k
m)
MALARGUE height a.s.l.
Lower limit estimation!.
VERY PRELIMINARY!
Lidar Auger Malargue - Argentina
Malargue Lidar - zenit angle= 90°March 7, 2002 - LR=50, raw resolution 30m