Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Efficient Continuous-Duty Bitter-Type Electromagnets for Cold Atom
  Experiments   We present the design, construction and characterization of Bitter-type
electromagnets which can generate high magnetic fields under continuous
operation with efficient heat removal for cold atom experiments. The
electromagnets are constructed from a stack of alternating layers consisting of
copper arcs and insulating polyester spacers. Efficient cooling of the copper
is achieved via parallel rectangular water cooling channels between copper
layers with low resistance to flow; a high ratio of the water-cooled surface
area to the volume of copper ensures a short length scale ~1 mm to extract
dissipated heat. High copper fraction per layer ensures high magnetic field
generated per unit energy dissipated. The ensemble is highly scalable and
compressed to create a watertight seal without epoxy. From our measurements, a
peak field of 770 G is generated 14 mm away from a single electromagnet with a
current of 400 A and a total power dissipation of 1.6 kW. With cooling water
flowing at 3.8 l/min, the coil temperature only increases by 7 degrees Celsius
under continuous operation.

13
The categories of this paper are: quant-ph
22
The categories of this paper are: chao-dyn
18
The categories of this paper are: econ
11
The categories of this paper are: hep-lat
31
The categories of this paper are: ao-sci
17
The categories of this paper are: q-fin
36
The categories of this paper are: cmp-lg
2
The categories of this paper are: math
20
The categories of this paper are: acc-phys
24
The categories of this paper are: dg-ga
19
The categories of this paper are: eess
1
The categories of this paper are: cs
9
The categories of this paper are: nlin
23
The categories of this paper are: solv-int
15
The categories of this paper are: nucl-ex
12
The categories of this paper are: nucl-th