Highly pixelated solid-state detectors offer outstanding capabilities in the identification and suppression of backgrounds from natural radioactivity. We present the background-identification strategies developed for the DAMIC experiment, which em-ploys silicon charge-coupled devices to search for dark matter. DAMIC has demonstrated the capability to disentangle and measure the activities of every β emitter from the 32Si, 238U and 232Th decay chains in the silicon target. Similar strategies will be adopted by the Selena Neutrino Experiment, which will employ hybrid amorphous 82Se/CMOS imagers to perform spectroscopy of ββ decay and solar neutrinos. We present the proposed experimental strategy for Selena to achieve zero-background in a 100-ton-year exposure.

1.
J.
Tiffenberg
,
M.
Sofo-Haro
,
A.
Drlica-Wagner
,
R.
Essig
,
Y.
Guardincerri
,
S.
Holland
,
T.
Volansky
, and
T.-T.
Yu
(
SENSEI Collabora-tion
), “
Single-electron and single-photon sensitivity with a silicon Skipper CCD
,”
Phys. Rev. Lett.
119
,
131802
(
2017
), arXiv:1706.00028 [physics.ins-det].
2.
J.
Ma
,
S.
Masoodian
,
D. A.
Starkey
, and
E. R.
Fossum
, “
Photon-number-resolving megapixel image sensor at room temperature without avalanche gain
,”
Optica
4
,
1474
1481
(
2017
).
3.
R.
Saldanha
,
R.
Thomas
,
R. H. M.
Tsang
,
A. E.
Chavarria
,
R.
Bunker
,
J. L.
Burnett
,
S. R.
Elliott
,
A.
Matalon
,
P.
Mitra
,
A.
Piers
,
P.
Privitera
,
K.
Ramanathan
, and
R.
Smida
, “
Cosmogenic activation of silicon
,”
Phys. Rev. D
102
,
102006
(
2020
), arXiv:2007.10584 [physics.ins-det].
4.
The unit keV electron-equivalent (keVee) is a measure of the amplitude of the ionization signal, i.e., the number of free charge carriers generated by a fast electron with initial kinetic energy of 1 keV that deposits its full energy in the target.
5.
A.
Aguilar-Arevalo
et al
(DAMIC Collaboration)
, “
Results on low-mass weakly interacting massive particles from a 11 kg-day target exposure of DAMIC at SNOLAB
,”
Phys. Rev. Lett.
125
,
241803
(
2020
), arXiv:2007.15622 [astro-ph.CO].
6.
A.
Aguilar-Arevalo
et al
(DAMIC Collaboration)
, “
First direct-detection constraints on eV-scale hidden-photon dark matter with DAMIC at SNOLAB
,”
Phys. Rev. Lett.
118
,
141803
(
2017
), arXiv:1611.03066 [astro-ph.CO].
7.
A.
Aguilar-Arevalo
et al
(DAMIC Colaboration)
, “
Constraints on light dark matter particles interacting with electrons from DAMIC at SNOLAB
,”
Phys. Rev. Lett.
123
,
181802
(
2019
), arXiv:1907.12628 [astro-ph.CO].
8.
S.
Holland
,
D.
Groom
,
N.
Palaio
,
R.
Stover
, and
M.
Wei
, “
Fully depleted, back-illuminated charge-coupled devices fabricated on high-resistivity silicon
,”
IEEE Trans. Electron Devices
50
,
225
238
(
2003
).
9.
A.
Aguilar-Arevalo
et al
(DAMIC Collaboration)
, “
Characterization of the background spectrum in DAMIC at SNOLAB
,”
Phys. Rev. D
105
,
062003
(
2022
), arXiv:2110.13133 [hep-ex].
10.
A.
Aguilar-Arevalo
et al
(DAMIC Collaboration)
, “
Measurement of the bulk radioactive contamination of detector-grade silicon with DAMIC at SNOLAB
,”
JINST
16
,
P06019
(
2021
), arXiv:2011.12922 [physics.ins-det].
11.
A. E.
Chavarria
et al, in preparation.
12.
J. L.
Orrell
,
I. J.
Arnquist
,
M.
Bliss
,
R.
Bunker
, and
Z. S.
Finch
, “
Naturally occurring 32Si and low-background silicon dark matter detectors
,”
Astropart. Phys.
99
,
9
20
(
2018
), arXiv:1708.00110 [physics.ins-det].
13.
R.
Agnese
et al
(SuperCDMS Collaboration)
, “
Projected sensitivity of the SuperCDMS SNOLAB experiment
,”
Phys. Rev. D
95
,
082002
(
2017
), arXiv:1610.00006 [physics.ins-det].
14.
A.
Aguilar-Arevalo
et al
(DAMIC Collaboration)
, “
Measurement of radioactive contamination in the high-resistivity silicon CCDs of the DAMIC experiment
,”
JINST
10
,
P08014
(
2015
), arXiv:1506.02562 [astro-ph.IM].
15.
A. E.
Chavarria
,
C.
Galbiati
,
B.
Hernandez-Molinero
,
A.
Ianni
,
X.
Li
,
Y.
Mei
,
D.
Montanino
,
X.
Ni
,
C. P.
Garay
,
A.
Piers
, and
H.
Wang
, “
Snowmass 2021 white paper: the Selena neutrino experiment
,” in
2022 Snowmass Summer Study
(
2022
) arXiv:2203.08779 [physics.ins-det].
16.
S. I.
Alvis
et al
(Majorana Collaboration)
, “
A search for neutrinoless double-beta decay in 76Ge with 26 kg-yr of exposure from the MAJO-RANA DEMONSTRATOR
,”
Phys. Rev. C
100
,
025501
(
2019
), arXiv:1902.02299 [nucl-ex].
17.
A.
Ali
,
A. V.
Borisov
, and
D. V.
Zhuridov
, “
Probing new physics in the neutrinoless double beta decay using electron angular correlation
,”
Phys. Rev. D
76
,
093009
(
2007
), arXiv:0706.4165 [hep-ph].
18.
F. F.
Deppisch
,
L.
Graf
, and
F.
Šimkovic
, “
Searching for new physics in two-neutrino double beta decay
,”
Phys. Rev. Lett.
125
,
171801
(
2020
), arXiv:2003.11836 [hep-ph].
19.
M.
Agostini
,
G.
Benato
,
J. A.
Detwiler
,
J.
Menéndez
, and
F.
Vissani
, “
Testing the inverted neutrino mass ordering with neutrinoless double-β decay
,”
Phys. Rev. C
104
,
L042501
(
2021
), arXiv:2107.09104 [hep-ph].
20.
M.
An
,
C.
Chen
,
C.
Gao
,
M.
Han
,
R.
Ji
,
X.
Li
,
Y.
Mei
,
Q.
Sun
,
X.
Sun
,
K.
Wang
,
L.
Xiao
,
P.
Yang
, and
W.
Zhou
, “
A low-noise CMOS pixel direct charge sensor, Topmetal-II-
,”
Nucl. Instrum. Meth. A
810
,
144
150
(
2016
), arXiv:1509.08611 [physics.ins-det].
21.
X.
Li
,
A. E.
Chavarria
,
S.
Bogdanovich
,
C.
Galbiati
,
A.
Piers
, and
B.
Polischuk
, “
Measurement of the ionization response of amorphous selenium with 122 keV γ rays
,”
JINST
16
,
P06018
(
2021
), arXiv:2012.04079 [physics.ins-det].
22.
A. E.
Chavarria
,
C.
Galbiati
,
X.
Li
, and
J. A.
Rowlands
, “
A high-resolution CMOS imaging detector for the search of neutrinoless double β decay in 82Se
,”
JINST
12
,
P03022
(
2017
), arXiv:1609.03887 [physics.ins-det].
23.
D.
Frekers
et al, “
High energy-resolution measurement of the 82Se(3He,t)82Br reaction for double-β decay and for solar neutrinos
,”
Phys. Rev. C
94
,
014614
(
2016
).
This content is only available via PDF.
You do not currently have access to this content.