Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Signals for Non-Commutative QED in $e \gamma$ and $\gamma \gamma$
  Collisions   We study the effects of non-commutative QED (NCQED) in fermion pair
production, $\gamma + \gamma \to f + \bar{f}$ and Compton scattering, $e +
\gamma \to e + \gamma$. Non-commutative geometries appear naturally in the
context of string/M-theory and gives rise to 3- and 4-point photon vertices and
to momentum dependent phase factors in QED vertices which will have observable
effects in high energy collisions. We consider $e^+ e^-$ colliders with
energies appropriate to the TeV Linear Collider proposals and the multi-TeV
CLIC project operating in $\gamma \gamma$ and $e\gamma$ modes. Non-commutative
scales roughly equal to the center of mass energy of the $e^+e^-$ collider can
be probed, with the exact value depending on the model parameters and
experimental factors. However, we found that the Compton process is sensitive
to $\Lambda_{NC}$ values roughly twice as large as those accessible to the pair
production process.

29
The categories of this paper are: funct-an
18
The categories of this paper are: econ
19
The categories of this paper are: eess
32
The categories of this paper are: atom-ph
24
The categories of this paper are: dg-ga
26
The categories of this paper are: bayes-an
37
The categories of this paper are: supr-con
21
The categories of this paper are: adap-org
23
The categories of this paper are: solv-int
14
The categories of this paper are: math-ph
28
The categories of this paper are: alg-geom
5
The categories of this paper are: gr-qc
6
The categories of this paper are: astro-ph
27
The categories of this paper are: comp-gas
35
The categories of this paper are: mtrl-th
36
The categories of this paper are: cmp-lg