Influence of cosmic rays on chemical composition of the atmosphere: data analysis and photochemical modelling

2002 ◽  
Vol 27 (6-8) ◽  
pp. 471-476 ◽  
Author(s):  
A. Krivolutsky ◽  
G. Bazilevskaya ◽  
T. Vyushkova ◽  
G. Knyazeva
1972 ◽  
Vol 45 ◽  
pp. 265-270
Author(s):  
L. M. Shul'man

The probable parent-molecules of radicals such as C3 and N2+ are discussed, and it is concluded that cometary nuclei may contain complicated organic molecules, such as C3H4, CH2N2, and C4H2. It is suggested that these molecules are formed by radiation synthesis in solid phase. In a time interval of order 107 to 109 yr bombardment from cosmic rays would be expected to transform the chemical composition to a depth of 1 m. Solar cosmic rays do not penetrate as far, and as a result the surface layer of the nucleus can be enriched with unsaturated hydrocarbons. After a critical concentration of this explosive material is reached a further burst of solar cosmic rays can initiate an explosion and thus an outburst in the comet's brightness. This mechanism is the only one advanced to date that can explain the synchronism of the energy output over the whole nuclear surface.


2021 ◽  
pp. 130672
Author(s):  
Emmanuelle Ferreira Requião Silva ◽  
Bruna Rosa da Silva Santos ◽  
Lucas Almir Cavalcante Minho ◽  
Geovani Cardoso Brandão ◽  
Márcio de Jesus Silva ◽  
...  

2011 ◽  
Vol 26 (03n04) ◽  
pp. 517-522
Author(s):  
◽  
ERMANNO VERCELLIN

The ALICE experiment is aimed at studying the properties of the hot and dense matter produced in heavy-ion collisions at LHC energies. In the first years of LHC operation the ALICE physics program will be focused on Pb - Pb and p - p collisions. The latter, on top of their intrinsic interest, will provide the necessary baseline for heavy-ion data. After its installation and a long commissioning with cosmic rays, in late fall 2009 ALICE participated (very successfully) in the first LHC run, by collecting data in p - p collisions at c.m. energy 900 GeV. After a short stop during winter, LHC operations have been resumed; the machine is now able to accelerate proton beams up to 3.5 TeV and ALICE has undertaken the data taking campaign at 7 TeV c.m. energy. After an overview of the ALICE physics goals and a short description of the detector layout, the ALICE performance in p - p collisions will be presented. The main physics results achieved so far will be highlighted as well as the main aspects of the ongoing data analysis.


1991 ◽  
Vol 126 ◽  
pp. 433-436
Author(s):  
Kunitomo Sakurai

AbstractThe chemical composition of galactic cosmic rays in their sources is similar to that of interstellar clouds or grains which are relatively enriched in refractory and siderophile elements as compared with the chemical composition of the solar atmosphere. Taking into account this fact, it is shown that the cosmic ray source matter can be identified as the dust or grains observed in the envelopes of red supergiant stars or the matter originally ejected from supernova explosions.


1972 ◽  
Vol 2 (3) ◽  
pp. 139-140 ◽  
Author(s):  
A. G. Fenton ◽  
K. B. Fenton

Evidence has been mounting for some years that cosmic rays have a dwell time in the disk of the Galaxy of 106-107 years. This evidence comes mainly from the study of the chemical composition of the cosmic rays, for if the particles were stored in the Galaxy for a longer time the heavy nuclei would suffer more collisions with interstellar matter and would be broken down into lighter nuclei or protons (see, for example, Shapiro).


2010 ◽  
Vol 716 (2) ◽  
pp. 1076-1083 ◽  
Author(s):  
M. Shibata ◽  
Y. Katayose ◽  
J. Huang ◽  
D. Chen

1981 ◽  
Vol 94 ◽  
pp. 71-72
Author(s):  
T. K. Gaisser ◽  
Todor Stanev ◽  
Phyllis Freier ◽  
C. Jake Waddington

Knowledge of the chemical composition is fundamental to understanding the origin, acceleration and propagation of cosmic rays. At energies much above 1014 eV, however, the detection of single primary cosmic rays is at present impossible because of their low flux, and the only source of information is from the cascades initiated by energetic primary particles in the atmosphere–the extensive air showers (EAS). A similar situation exists for the study of hadronic interactions above 1015 eV. A recent EAS experiment (Goodman et al., 1979) suggests the possibility that the spectrum becomes increasingly rich in heavy nuclei as the total energy per nucleus approaches 1015 eV. Above that energy the overall spectrum steepens and the question of composition is almost completely open.


Sign in / Sign up

Export Citation Format

Share Document