Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On a systematic bias in SBF-based distances due to gravitational
  microlensing   The effect of gravitational microlensing on the determination of
extragalactic distances using surface brightness fluctuations (SBF) technique
is considered and a method to calculate SBF amplitudes in presence of
microlensing is presented. With a simple approximation for the magnification
power spectrum at low optical depth the correction to the SBF-based luminosity
distance is calculated. The results suggest the effect can be safely neglected
at present but may become important for SBF-based Hubble diagrams at luminosity
distances of about 1 Gpc and beyond.

3
The categories of this paper are: physics
28
The categories of this paper are: alg-geom
5
The categories of this paper are: gr-qc
33
The categories of this paper are: plasm-ph
8
The categories of this paper are: hep-ex
31
The categories of this paper are: ao-sci
19
The categories of this paper are: eess
17
The categories of this paper are: q-fin
27
The categories of this paper are: comp-gas
18
The categories of this paper are: econ
21
The categories of this paper are: adap-org
35
The categories of this paper are: mtrl-th
10
The categories of this paper are: q-bio
2
The categories of this paper are: math
7
The categories of this paper are: hep-th
23
The categories of this paper are: solv-int