Generation and structure of extremely large clusters in pulsed jets

Abstract

Extremely large xenon clusters with sizes exceeding the predictions of the Hagena scaling law by several orders of magnitude are shown to be produced in pulsed gas jets. The cluster sizes are determined using single-shot single-particle imaging experiments with short-wavelength light pulses from the free-electron laser in Hamburg (FLASH). Scanning the time delay between the pulsed cluster source and the intense femtosecond x-ray pulses first shows a main plateau with size distributions in line with the scaling laws, which is followed by an after-pulse of giant clusters. For the extremely large clusters with radii of several hundred nanometers the x-ray scattering patterns indicate a grainy substructure of the particles, suggesting that they grow by cluster coagulation.

Coupled motion of Xe clusters and quantum vortices in He nanodroplets

“…The image plane was located 565 mm behind the interaction point on the XFEL beam axis. striking symmetries that invite rationalization in terms of corresponding symmetric Xe cluster configurations, which may be estimated by modelling [20] as described in the SM [15]. In general, however, the DCDI iterative phase retrieval algorithm [11] is applied in order to obtain the density distributions of the Xe clusters from the diffraction images.…”

Recombination-Enhanced Surface Expansion of Clusters in Intense Soft X-Ray Laser Pulses

“…An ion time-of-flight (TOF) spectrometer with a small entrance aperture was positioned perpendicular to FEL and cluster beam axes. Further details of the experimental setup are described elsewhere [41]. From the single-cluster images, the cluster size was determined by comparison with Mie simulations (cf.…”

“…Starting with the very first experiment at an FEL in the short-wavelength range [21], studies on atomic clusters have contributed significantly to a fundamental understanding of ultrafast x-ray induced dynamics in finite systems [22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39][40]. The possibility to image single particles via single-shot x-ray diffraction enables novel insight into the formation and morphology of clusters [7,[41][42][43] as well as ultrafast transient changes of their electronic properties [44]. Further, since both initial cluster size and laser intensity (or fluence) are encoded in the diffraction image [44,45], the combination of x-ray imaging and ion spectroscopy enables studying intense x-ray laser-cluster interactions with unprecedented control over these experimental parameters.…”

Investigation of the on-axis atom number density in the supersonic gas jet under high gas backing pressure by simulation

“…Thus one a Author to whom correspondence should be addressed: kimd@postech.ac.kr 2158-3226/2015/5(10)/107220/7 5, 107220-1 © Author(s) 2015 expects the cluster size deviation when the scaling law is used to estimate the cluster size under a high gas backing pressure. Up to now, there have existed many papers about the investigation of the gas jet and its cluster size, [9][10][11][12][13][14][15][16][17][18][19] and there have been papers reporting the cluster size deviation from the size expected by the scaling laws 20,21 and some works concerned about the understanding of the deviation. 22 In Ref.…”