title: Hydrated thymine cluster in the supersonic gas jet.
abstract: Fragmentation of hydrated thymine clusters in the gas phase induced by UV laser pulse at 266 nm was studied by means of time-of-flight (TOF) mass spectrometry. Hydrated thymine clusters were produced by supersonic expansion in the gas jet in a high vacuum region. The range of laser intensity for ionisation of the gaseous targets was from 10(6) to 10(9) W cm(-2). In the condition of low laser intensity, the peaks corresponding to hydrated thymine clusters [(C(5)H(6)N(2)O(2))(m)(H(2)O)(n)] and large mass fragments from them were obtained mainly. In the laser intensity region from 10(7) to 10(8) W cm(-2), the fragment ions released from thymine such as HCNH(+), HNCO(+), CH(2)CCHNH(+), CH(3)CCHNH(+), C(3)H(4)O(+), etc. were mainly detected due to C-C and C-N bond breaks in a ring structure of thymine.
authors.affiliation: Division of Electrical, Electronic and Information Engineering, Graduate School of Engineering, Osaka University, Suita, Osaka, Japan. kagawa@nf.eie.eng.osaka-u.ac.jp
authors.forename: Takeshi
authors.initials: T
authors.lastname: Kagawa
authors.forename: Koji
authors.initials: K
authors.lastname: Aikawa
authors.forename: Fuminobu
authors.initials: F
authors.lastname: Sato
authors.forename: Yushi
authors.initials: Y
authors.lastname: Kato
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Iida
mesh_terms: D016000:Cluster Analysis; D003198:Computer Simulation; D004247:DNA / Q000737:chemistry* / Q000528:radiation effects*; D004249:DNA Damage; D004307:Dose-Response Relationship, Radiation; D005740:Gases / Q000737:chemistry; D008956:Models, Chemical; D011829:Radiation Dosage; D011874:Radiometry / Q000379:methods; D013941:Thymine / Q000737:chemistry* / Q000528:radiation effects*; D014466:Ultraviolet Rays; D014867:Water / Q000737:chemistry*
chemical_list: D005740:Gases; D014867:Water; D004247:DNA; D013941:Thymine