Cosmicray induced aerosol nucleation

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Cosmic-ray induced aerosol nucleation

• Introduction to the laboratory experiments

Takashi SAKO, Kimiaki MASUDA, Yoshitaka
ITOW, Yutaka MATSUMI (Solar-Terrestrial
Environment Laboratory, Nagoya-U, Japan) Kanya
KUSANO (JAMSTEC)
International Workshop on Variabilities of
Solar-Cosmic and Terrestrial Environment 4-6
December, 2008, JAMSTEC Yokohama
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CR-Cloud connection
Cosmic-Ray
Low Cloud Cover
Svensmark, AG, 48, 1.18, 2007
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Cloud chamber(simple mind of particle physicists)

• CR-Cloud connection is naturally acceptable.
• Quantitative explanation from ionization to cloud
  formation is indispensable.

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Cluster nucleation through ions-gt Cloud
Condensation Nucleus
CLOUD Collaboration (CERN-SPSC-2004-023)
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Nucleation accelerated by Ions
Yu and Turco (2001)
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Cosmic-ray shower
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CR ionization rate
Usoskin et al., J. Atmospheric and Solar-Terr.
Phys., 66, 1791, 2004
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CR Flux Particle dependence
1GV rigidity cutoff 3km altitude 400MV FFP -
Muons are dominant in number in high energy. -
Neutron and photon are not ionizing particles.
EXPACS V2.13, Sato Nitta, Radiat.Res., 166,
544, 2006
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Laboratory experiments
SKY Experiment (Svensmark et al., Proc. R. Soc.
A, 463, 385, 2007)
253nm UV
Moisture SO2, O3 Controlled air
7m3 reaction chamber
CR muon (137Cs gamma)
Ion density gt3nm particle
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Ion aerosol density relation
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Everything can be known!(simple mind)
Usoskin et al., 2004
Of course, hundred of parameters!
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CLOUD experiment(facility in CERN)
Charged particle from accelerator
SKY-like Reaction chamber (pressurized)
Cloud chamber (supersaturation)
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CLOUDmeasureseverything
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Processes covered bySKY and CLOUD
SKY experiment
CLOUD Collaboration (CERN-SPSC-2004-023)
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Processes covered bySKY and CLOUD
SKY experiment
CLOUD Collaboration (CERN-SPSC-2004-023)
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CLOUD Programme

• Aerosol experiments
• Gas-to-particle conversion
• Growth of CN into CCN
• Activation of CCN into cloud droplets
• Dynamics of CCN activation and kinetic
  limitations on cloud droplets
• Production of NO and OH and their influence on
  aerosols
• Production of aerosol precursors from trace gases
• Effect of highly ionising particles
• Ice particle experiments
• Ice particle formation by deposition nucleation
• Ice particle formation by freezing nucleation and
  contact nucleation
• Secondary production of ice particles
• Efficiency of highly-charged evaporation nuclei
  as IN
• Effect of freezing-thawing cycles on IN
  efficiency
• Growth of ice particles in mixed-phase clounds
• Reflectivities of ice and liquid clouds
• Freezing mechanism of polar stratospheric clouds
• Cloud electricity experiments
• Effect of charge and electric field on the
  coalescence efficiency of droplets

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CLOUD

• Tests particle, cloud formation in well
  controlled gas (composition, pressure,
  temperature,)
• Measures everything
• Tests the effects of ionization particles
• Is the ultimate weapon
• Costs 9.1M euros, spends 8 years

http//cloud.web.cern.ch/cloud/
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Ionization Particle dependence
1GV rigidity cutoff 3km altitude 400MV FFP
ion/cm3/s Total 6.1 Muon
2.4 e/-, ? 2.2 p, n
1.5
EXPACS V2.13, Sato Nitta, Radiat.Res., 166,
544, 2006
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Ionization loss
Ion production rate / unit length
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Cloud chamber again
CR muon
a-particle (ppnn)
( http//www.kiribako-rado.co.jp/play/p-top-1.html
)
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JAMSTEC-NAGOYA project

• CRs are not only muons
• Effect of non-relativistic protons/neutrons
• Start from a SKY-like experiment with different
  type/energy of particles (Tsukuba, RIKEN, RCNP,
  CERN,)
• High altitude, underground experiment with
  different CR rate (Norikura, Kamioka,)
• SKY
• ? CLOUD facility at CERN
• ? Our idea mobile facility for parameter survey
• Feedback to the Earth simulator to evaluate
  quantitative effect to the climate

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Nagoya Chamber
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Leading experiments

• Ionization by low energy alpha particles
• Talk by Prof. Nagato
• Ionization by low
  energy protons
• Talk by Prof. Tomita
• Unification of individual
• experiment into modeling
• is important

Nagato et al., Aerosol Science, 36, 1036, 2005
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Conclusion

• Existence of ions is thought to play an important
  role in nano-particle formation
• Ions-particle correlation is (will be) tested by
  laboratory experiments quantitatively
• Tests must be performed under various conditions,
  especially taking the CR ionization process into
  account
• Feedback to the modeling and evaluation to the
  climate effect is important

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World race??
Its not a 100m race, but 42.195 km. route
not defined
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backup
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Nucleation speed
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Chemical processes Aerosol
Yu and Turco, JGR, 106, 4797, 2001