Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Characterization of a medium size Xe/TMA TPC instrumented with microbulk
  Micromegas, using low-energy $\gamma$-rays   NEXT-MM is a general-purpose high pressure (10 bar, $\sim25$ l active volume)
Xenon-based TPC, read out in charge mode with an 8 cm $\times$8 cm-segmented
700 cm$^2$ plane (1152 ch) of the latest microbulk-Micromegas technology. It
has been recently commissioned at University of Zaragoza as part of the R&D of
the NEXT $0\nu\beta\beta$ experiment, although the experiment's first stage is
currently being built based on a SiPM/PMT-readout concept relying on
electroluminescence. Around 2 million events were collected during the last
months, stemming from the low energy $\gamma$-rays emitted by a $^{241}$Am
source when interacting with the Xenon gas ($\epsilon$ = 26, 30, 59.5 keV). The
localized nature of such events above atmospheric pressure, the long drift
times, as well as the possibility to determine their production time from the
associated $\alpha$ particle in coincidence, allow the extraction of primordial
properties of the TPC filling gas, namely the drift velocity, diffusion and
attachment coefficients. In this work we focus on the little explored
combination of Xe and trimethylamine (TMA) for which, in particular, such
properties are largely unknown. This gas mixture offers potential advantages
over pure Xenon when aimed at Rare Event Searches, mainly due to its Penning
characteristics, wave-length shifting properties and reduced diffusion, and it
is being actively investigated by our collaboration. The chamber is currently
operated at 2.7 bar, as an intermediate step towards the envisaged 10 bar. We
report here its performance as well as a first implementation of the
calibration procedures that have allowed the extension of the previously
reported energy resolution to the whole readout plane (10.6%FWHM@30keV).

2
The categories of this paper are: math
12
The categories of this paper are: nucl-th
20
The categories of this paper are: acc-phys
1
The categories of this paper are: cs
32
The categories of this paper are: atom-ph
6
The categories of this paper are: astro-ph
18
The categories of this paper are: econ
0
The categories of this paper are: hep-ph
15
The categories of this paper are: nucl-ex
11
The categories of this paper are: hep-lat
14
The categories of this paper are: math-ph
34
The categories of this paper are: chem-ph
23
The categories of this paper are: solv-int
36
The categories of this paper are: cmp-lg
37
The categories of this paper are: supr-con
27
The categories of this paper are: comp-gas