Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Tomographic phase and attenuation extraction for a sample composed of
  unknown materials using X-ray propagation-based phase-contrast imaging   Propagation-based phase-contrast X-ray imaging (PB-PCXI) generates image
contrast by utilizing sample-imposed phase-shifts. This has proven useful when
imaging weakly-attenuating samples, as conventional attenuation-based imaging
does not always provide adequate contrast. We present a PB-PCXI algorithm
capable of extracting the X-ray attenuation, $\beta$, and refraction, $\delta$,
components of the complex refractive index of distinct materials within an
unknown sample. The method involves curve-fitting an error-function-based model
to a phase-retrieved interface in a PB-PCXI tomographic reconstruction, which
is obtained when Paganin-type phase-retrieval is applied with incorrect values
of $\delta$ and $\beta$. The fit parameters can then be used to calculate true
$\delta$ and $\beta$ values for composite materials. This approach requires no
a priori sample information, making it broadly applicable. Our PB-PCXI
reconstruction is single distance, requiring only one exposure per tomographic
angle, which is important for radiosensitive samples. We apply this approach to
a breast-tissue sample, recovering the refraction component, $\delta$, with 0.6
- 2.4\% accuracy compared to theoretical values.

15
The categories of this paper are: nucl-ex
11
The categories of this paper are: hep-lat
6
The categories of this paper are: astro-ph
28
The categories of this paper are: alg-geom
7
The categories of this paper are: hep-th
12
The categories of this paper are: nucl-th
20
The categories of this paper are: acc-phys
18
The categories of this paper are: econ
27
The categories of this paper are: comp-gas
10
The categories of this paper are: q-bio
24
The categories of this paper are: dg-ga
14
The categories of this paper are: math-ph
29
The categories of this paper are: funct-an
1
The categories of this paper are: cs
8
The categories of this paper are: hep-ex
36
The categories of this paper are: cmp-lg