Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Two clock transitions in neutral Yb for the highest sensitivity to
  variations of the fine-structure constant   We propose a new frequency standard based on a $4f^{14} 6s6p~ ^3\!P_0 -
4f^{13} 6s^2 5d ~(J=2)$ transition in neutral Yb. This transition has a
potential for high stability and accuracy and the advantage of the highest
sensitivity among atomic clocks to variation of the fine-structure constant
$\alpha$. We find its dimensionless $\alpha$-variation enhancement factor to be
$K=-15$, in comparison to the most sensitive current clock (Yb$^+$ E3, $K=-6$),
and it is 18 times larger than in any neutral-atomic clocks (Hg, $K=0.8$).
Combined with the unprecedented stability of an optical lattice clock for
neutral atoms, this high sensitivity opens new perspectives for searches for
ultralight dark matter and for tests of theories beyond the standard model of
elementary particles. Moreover, together with the well-established $^1\!S_0 -\,
^3\!P_0$ transition one will have two clock transitions operating in neutral
Yb, whose interleaved interrogations may further reduce systematic
uncertainties of such clock-comparison experiments.

12
The categories of this paper are: nucl-th
1
The categories of this paper are: cs
22
The categories of this paper are: chao-dyn
21
The categories of this paper are: adap-org
9
The categories of this paper are: nlin
19
The categories of this paper are: eess
24
The categories of this paper are: dg-ga
25
The categories of this paper are: patt-sol
7
The categories of this paper are: hep-th
28
The categories of this paper are: alg-geom
18
The categories of this paper are: econ
32
The categories of this paper are: atom-ph
6
The categories of this paper are: astro-ph
17
The categories of this paper are: q-fin
15
The categories of this paper are: nucl-ex
11
The categories of this paper are: hep-lat