adsorption and desorption in ism
TRANSCRIPT
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Gas-grain modeling for interstellarGas-grain modeling for interstellar
chemistrychemistry
Supervisors: MINISSALE M.
P. THEULE
Presented by: AURI
SHARMA
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CONTENTS
●
Introduction
1)Interstellar medium2)Processes3)Experimental setup
●
Simulation
1)Gas-grain model
●Experiments
1)ure H!O
!)ure CO")ure CO!#)Mixture o$ H!O%CO!
●Conclusion
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INTRO&UCTION
&i$$use
medium
&ense
medium Molecular cloudImage credit: Kohler M. et al. Edited ! "harma G.
#redit: $ue%o M. et al.
1'( cemical
compounds
O*ser+ed in
molecular clouds,
ISM
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HOW do they form ????
Image credit: KI&&-PK' and http:((sta.on.r(*l+m(astron2e(&,MEI& / edited ! "harma G.
1- &UST
http://staff.on.br/jlkm/astron2e/AT_MEDIAhttp://staff.on.br/jlkm/astron2e/AT_MEDIA
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.ormation o$ molecules on &UST
Ho/ do /e o*ser+e tem in 0as pase in spectroscop 22222
COSMIC RA3S4
Image credit: 0Khler M. et al. 45 &165)/ edited ! "harma G.
5ic te psical penomenon occurs tere 22222
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Adsorption
rocesses and experimental setup
Cosmic ras
'7Photons
Interstellar medium
6a*orator
"pecimen chamer"P8&!
#redit:Philip 9o-mann
#redit: $eu%o M et al.
"ample
H
7
)
m
*
M"
;a+eshoreinstrument
Temperature
ro0rammed
&esorption
8T&)
< e e d a c +
% o l t a g e
esorption
● Adsorption
●&esorption
● &i$$usion
, e l e s c o p
e
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as%0rain modelin0
Ho/ to e+aluate T& 22222
Polan!i-=igner E>uation:
8 ? esorption rate$ ? $o. o molecules per s>uare cm
n? order o esorption@eta ? ramp rate
E ? esorption energ!, ? esorption temperature
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Experiments
●ure H!O
●ure CO
●ure CO!
●Mixture o$ H!O%CO!
Atain,P
#alculate energ!rom ,P
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H!O
Experiment
M o l e c u
l e s c m - 2 K - 1
&morphousphase o 92A
● E:des ;
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CO
Experiment
M o
l e c u
l e s c m - 2 K - 1
● E:des ; 987.0±36.00 ● A ; 1(1!?1 sec%1● T:des B "< ● Residence time ;
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CO!
Experiment
M o l e c u
l e s c m - 2 K - 1
● E:des ; !#(±50.00
● A ; 1(1!?1 sec%1● T:des B = ● Residence time ; #>@ x 1(1( ears
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Mixture
CO!%H!O
M
o l e c u
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