THE EFFECT OF BROADBAND SOFT X-RAYS IN SO₂-CONTAINING ICES: IMPLICATIONS ON THE PHOTOCHEMISTRY OF ICES TOWARD YOUNG STELLAR OBJECTS

Laboratory Investigation of X-Ray Photolysis of Methanol Ice and Its Implication on Astrophysical Environments

“…More details were given by Pilling and Bergantini. 20 Briefly, gaseous CH 3 OH was slowly deposited into a clean ZnSe substrate crystal couple to helium closed-cycle cryostat at the vacuum chamber, through a capillary tube kept about 0.5 cm from the crystal during about 5 minutes forming ice with 1.1 mm of initial thickness.…”

“…Photon flux a (cm -2 s -1 ) TS E (12 K) (years) Reference and comments KBOs typical orbit (~40 AU) 5 × 10 3 2.7 × 10 7 Considering r -2 law 20,25 Vicinity of Saturn orbit (~9.0 AU) 6.5 × 10 5 2.3 × 10 5 From paper 26 Triton orbit (~30 AU) 9 × 10 6 1.6 × 10 4 Considering r -2 law 20,25 Saturn orbit(~9.5 AU) 8 × 10 9 1.6 × 10 1 Considering r -2 law 20,25 YSO TW Hydra at 40 AU 9 × 10 11 1.5 × 10 -1 Non-attenuated flux (at 1 AU and considering r -2 law) 27 Earth orbit (Sun typical flux at 1AU) 3 × 10 13 5.1 × 10 -3 From paper 25 Lab. 1 × 10 14 1.4 × 10 -3 SGM beam line in off-focus and white beam mode at the LNLS/CNPEN synchrotron light source at São Paulo/Brazil 20 YSO typical flux at 1 AU 6 × 10 15 1.9 × 10 -5 Non-attenuated flux 28 a VUV and soft X-rays (from 6 eV to 2000 eV).…”

Photochemistry and desorption induced by X-rays in water rich astrophysical ice analogs: implications for the moon Enceladus and other frozen space environments

“…The ionizing radiation produced by stars induces chemical changes in the surrounding matter (circumstellar and interstellar gas, solid-phase molecules (icy grains), planets, and other orbiting bodies), enhancing the chemical complexity of these environments. [1][2][3][4][5][6][7][8][9] As pointed out by Pilling and Bergantini 10 following the discussion of Imanishi et al 11 and Siebenmorgen and Krügel, 12 in the case of newborn stars, also called young stellar objects (YSOs), the material falling toward the stars makes the emission of X-rays even more intense than in stars in the main sequence. Such X-ray photons are capable of traversing large column densities of gas before being absorbed.…”

“…Such X-ray photons are capable of traversing large column densities of gas before being absorbed. [13][14][15] Pilling and Bergantini 10 have pointed out that in space environments the photochemical complexity increases as the energy of the incoming photons increases, which leads neutral molecules to excited states, radicals, and ions at higher energies. In addition, in the case of X-rays, the produced high-energy ($keV) photoelectrons and low-energy ($eV) induced secondary electrons also represent an extra source of molecular processing.…”

Uma Abordagem Baseada Em Websocket Para Comunicação Em Tempo Real No Genemaislab

“…Fluxo de fótons fornecido como uma soma de UV e raios-X moles (~ 10 -2000 eV) fornecido para o Sistema Solar Exterior nas proximidades de Saturno(BENNETT et al, 2007). Fluxo de elétrons fornecido no Sistema Solar Exterior nas proximidades de Saturno(PILLING & BERGANTINI, 2015). necessário para a abundância da molécula ser reduzida à metade do valor limite atingido na fluência de equilíbrio químico.…”