Pellet of Allende powder (n°2) | DAYSY

Sample

Name: Pellet of Allende powder (n°2)

Owner of sample

Database

DAYSY

Experimentalists

Rosario Brunetto

Origin of sample

Date: 2012-06-20
Provider: IAS, Orsay

Image

Panel A: mosaic of optical microscope images obtained on one Allende pellet n°2, with the indication of the irradiation conditions performed over diameters of 4 mm; a central area (2 mm in diameter) remained non-irradiated. Panel B: optical image (10x objective), showing the typical surface roughness and porosity, along with compositional heterogeneity reflected by different contrasts. Panel C: side and front views of irradiation geometry of the experimental setup; a mask is used to protect earlier irradiated spots from sputter deposits from the subsequent irradiation steps (4 mm hole); all sizes are given in millimeters. Panel D: a picture showing the two pellets installed in the SIDONIE sample holder. From Brunetto et al. (2014).

Physical characteristics

Thickness: 200.0 $\pm$ 100.0 ${\mu}m$
Diameter: 13000.0 ${\mu}m$
Mass: 0.1 $\pm$ 0.02 $g$
Substrate material: KBr
Substrate comments: KBr window, 2 mm thick, 13 mm diameter. The KBr is used as a substrate to avoid meteorite pellet break.
Comments: Pellet prepared by pressing (7 tons for 10 min) about 100 mg of the original dust (grain size 1–100 µm) on top of a KBr substrate pellet. The KBr is used as a substrate to avoid pellet break. Thickness of the meteorite pellet is large enough (>200 µm) to avoid contribution of KBr to the spectra.
Area D, irradiated with $3~10^{15}$ $He^+.cm^{-2}$

Sample environment: Temperature

Temperature: 300.0 $\pm$ 5.0 $K$
Temperature max: 300.0 $\pm$ 5.0 $K$

Sample environment: Fluid

Type: ambient air
Fluid pressure: 1.0 $bar$

Sample environment: Irradiation

Source: ions accelerator
Chronology: before spectrum

Particle

Family: atoms and molecules
Type: atomic ions
Particle: $He^+$
Energy: 40.0 $keV.particle^{-1}$
Particle fluence: 3e+16 $particle.m^{-2}$

Documentation and publication

Publications

Brunetto et al., 2014, Icarus, 237, 292

Layers in sample

Number

Layers

Pellet of Allende powder , 200.0 ${\mu}m$

Sample processings

Title

Allende pellet preparation

Precursors

Matters

Produced sample

Sample

Pellet of Allende powder (n°2) (this sample)

Processing steps

Step	Chronology	Date	Type	Process	Changes
#1	before layer formation	2012-06-20	mechanical	pressing granular KBr to form the pellet substrat
#2	during layer formation	2012-06-20	mechanical	pressing Allende powder on top of the KBr substrate (7 tons for 10 min)