Muography is a rapidly developing and non-destructive tomographic technology that uses cosmic ray muons. Due to the natural presence and deeper penetration of cosmic ray muons, scientists have performed various pioneer studies in fields, such as customs security, the internal imaging of volcanoes, scientific archaeology, and others. With unique advantages, muography has gained increasing attention from archaeologists as a novel and innovative tool to investigate large-scale archaeological sites. This approach may be especially helpful for identifying endangered cultural relics and monuments. In the work, we employ a compact, rugged, and portable muon imaging system, CORMIS (COsmic Ray Muon Imaging System), deployed at up to six measurement locations to perform a case study of three-dimensional muography in Xi’an city, China. Cultural cities, such as Xi’an, have long histories and could benefit from innovative techniques used to investigate, conserve, and protect large historical sites. In this paper, we present in detail a high resolution survey on a rampart of a Xi’an defensive wall in demand of urgent protection. The survey data are carefully processed with advanced statistical methods newly introduced in muography, and the results indicate density anomalies inside the rampart with unprecedented levels of precision. The density anomalies are potential safety hazards and need to be eliminated as soon as possible. The successful implementation of this survey significantly encourages more engagement on the tangible application of high-precision 3D muography in archaeological investigations and protection projects around the world.

1.
W.
Zilin
, “The museum of Qin Shi Huang Terracotta warriors and horses,” (1985); see https://unesdoc.unesco.org/notice?id=p::usmarcdef_0000067822.
2.
M.
Yu
,
Xi’an Ancient City Wall and the Bell Tower: History. Arts and Science
, Chinese ed. (
Xi an Jiaotong University Press
,
2000
).
3.
State Administration of Cultural Heritage
, “City walls of the Ming and Qing dynasties,” (2008); see https://whc.unesco.org/en/tentativelists/5324/.
4.
State Council of the People’s Republic of China
, “State council on the announcement of the heritage sites under the national protection of the first batch,” (2014); see http://www.gov.cn/guoqing/2014-07/21/content_2721152.htm.
5.
China Daily
, “A section of Xi’an city wall collapsed after rainfall,” (2006); see http://www.chinadaily.com.cn/china/2006-07/27/content_650562.htm.
6.
China Global Television Network
, “Ancient Xi’an city wall collapses due to severe rainfall,” (2020); see https://news.cgtn.com/news/2020-08-09/Ancient-Xi-an-city-wall-collap ses-due-to-severe-rainfall-SOzuPoS8ms/index.html.
7.
Y.
Liu
,
Y.
Huang
, and
L.
Hao
, “
Investigation on damaged aprons at northern section of Xi’an ancient wall
,”
Geotech. Investig. Archaeol. Surv.
42
,
83
87
(
2011
), see https://kns.cnki.net/kcms/detail/detail.aspx?FileName=GCKC201411018&DbName=CJFQ2014.
8.
Xi’an City Wall Management Committee
, “Xi’an defensive wall protection,” (2017); see https://www.xacitywall.com/zhuantizhuanlan/wenwubaohu/2019-05-08/1041.html.
9.
J. C.
Wynn
, “
A review of geophysical methods used in archaeology
,”
Geoarchaeology
1
,
245
257
(
1986
).
10.
J.
Lakshmanan
and
J.
Montlucon
, “
Microgravity probes the great pyramid
,”
Lead. Edge
6
,
10
17
(
1987
).
11.
F.
Büker
,
A. G.
Green
, and
H.
Horstmeyer
, “
Shallow 3-D seismic reflection surveying: Data acquisition and preliminary processing strategies
,”
Geophysics
63
,
1434
1450
(
1998
).
12.
B. W.
Bevan
, “
An early geophysical survey at Williamsburg, USA
,”
Archaeol. Prospect.
7
,
51
58
(
2000
).
13.
N.
Linford
, “
The application of geophysical methods to archaeological prospection
,”
Rep. Prog. Phys.
69
,
2205
2257
(
2006
).
14.
W.
Zheng
,
X.
Li
,
N.
Lam
,
X.
Wang
,
S.
Liu
,
X.
Yu
,
Z.
Sun
, and
J.
Yao
, “
Applications of integrated geophysical method in archaeological surveys of the ancient Shu ruins
,”
J. Archaeol. Sci.
40
,
166
175
(
2013
).
15.
G.
El-Qady
,
M.
Metwaly
, and
M. G.
Drahor
, “Geophysical techniques applied in archaeology,” in Archaeogeophysics, Natural Science in Archaeology, edited by G. El-Qady and M. Metwaly (Springer International Publishing, Cham, 2019), pp. 1–25.
16.
J. C.
Alldred
, “
A fluxgate gradiometer for archaeological surveying
,”
Archaeometry
7
,
14
19
(
1964
).
17.
N. T.
Linford
, “
Geophysical survey at Boden Vean, Cornwall, including an assessment of the microgravity technique for the location of suspected archaeological void features
,”
Archaeometry
40
,
187
216
(
1998
).
18.
C.
Orfanos
and
G.
Apostolopoulos
, “
2D-3D resistivity and microgravity measurements for the detection of an ancient tunnel in the Lavrion area, Greece
,”
Near Surf. Geophys.
9
,
449
457
(
2011
).
19.
P.
Barone
and
C.
Ferrara
, “
Non-invasive moisture detection for the preservation of cultural heritage
,”
Heritage
1
,
163
170
(
2018
).
20.
N.
Lesparre
,
D.
Gibert
,
J.
Marteau
,
Y.
Déclais
,
D.
Carbone
, and
E.
Galichet
, “
Geophysical muon imaging: Feasibility and limits: Geophysical muon imaging
,”
Geophys. J. Int.
183
,
1348
1361
(
2010
).
21.
P.
Checchia
, “
Review of possible applications of cosmic muon tomography
,”
J. Instrum.
11
,
C12072
(
2016
).
22.
G.
Yang
,
T.
Clarkson
,
S.
Gardner
,
D.
Ireland
,
R.
Kaiser
,
D.
Mahon
,
R. A.
Jebali
,
C.
Shearer
, and
M.
Ryan
, “
Novel muon imaging techniques
,”
Philos. Trans. R. Soc. A: Math. Phys. Eng. Sci.
377
,
20180062
(
2019
).
23.
S.
Procureur
, “
Muon imaging: Principles, technologies and applications
,”
Nucl. Instrum. Methods Phys. Res. A: Accel. Spectrom. Detect. Assoc. Equip.
878
,
169
179
(
2018
).
24.
G.
Bonomi
,
P.
Checchia
,
M.
D’Errico
,
D.
Pagano
, and
G.
Saracino
, “
Applications of cosmic-ray muons
,”
Prog. Part. Nucl. Phys.
112
,
103768
(
2020
).
25.
L.
Bonechi
,
R.
D’Alessandro
, and
A.
Giammanco
, “
Atmospheric muons as an imaging tool
,”
Rev. Phys.
5
,
100038
(
2020
).
26.
L.
Cimmino
, “
Principles and perspectives of radiographic imaging with muons
,”
J. Imaging
7
,
253
(
2021
).
27.
A.
Lechmann
,
D.
Mair
,
A.
Ariga
,
T.
Ariga
,
A.
Ereditato
,
R.
Nishiyama
,
C.
Pistillo
,
P.
Scampoli
,
F.
Schlunegger
, and
M.
Vladymyrov
, “
Muon tomography in geoscientific research—A guide to best practice
,”
Earth-Sci. Rev.
222
,
103842
(
2021
).
28.
Muography: Exploring Earth’s Subsurface with Elementary Particles, Geophysical Monograph Series, edited by L. Oláh, H. Tanaka, and D. Varga (Wiley, Hoboken, NJ, 2022).
29.
H. K. M.
Tanaka
, Principles of Muography and Pioneering Works, Geophysical Monograph Series, edited by L. Oláh, H. K. M. Tanaka, and D. Varga (Wiley, 2022), 1st ed., pp. 1–17.
30.
P. J.
Mohr
,
D. B.
Newell
, and
B. N.
Taylor
, “
CODATA recommended values of the fundamental physical constants: 2014
,”
Rev. Mod. Phys.
88
,
035009
(
2016
).
31.
P. K. F.
Grieder
,
Cosmic Rays at Earth
(
Elsevier Science
,
2001
).
32.
M.
Tanabashi
,
K.
Hagiwara
,
K.
Hikasa
,
K.
Nakamura
,
Y.
Sumino
,
F.
Takahashi
,
J.
Tanaka
,
K.
Agashe
,
G.
Aielli
,
C.
Amsler
,
M.
Antonelli
,
D. M.
Asner
,
H.
Baer
,
S.
Banerjee
,
R. M.
Barnett
,
T.
Basaglia
,
C. W.
Bauer
,
J. J.
Beatty
,
V. I.
Belousov
,
J.
Beringer
,
S.
Bethke
,
A.
Bettini
,
H.
Bichsel
,
O.
Biebel
,
K. M.
Black
,
E.
Blucher
,
O.
Buchmuller
,
V.
Burkert
,
M. A.
Bychkov
,
R. N.
Cahn
,
M.
Carena
,
A.
Ceccucci
,
A.
Cerri
,
D.
Chakraborty
,
M.-C.
Chen
,
R. S.
Chivukula
,
G.
Cowan
,
O.
Dahl
,
G.
D’Ambrosio
,
T.
Damour
,
D.
de Florian
,
A.
de Gouvêa
,
T.
DeGrand
,
P.
de Jong
,
G.
Dissertori
,
B. A.
Dobrescu
,
M.
D’Onofrio
,
M.
Doser
,
M.
Drees
,
H. K.
Dreiner
,
D. A.
Dwyer
,
P.
Eerola
,
S.
Eidelman
,
J.
Ellis
,
J.
Erler
,
V. V.
Ezhela
,
W.
Fetscher
,
B. D.
Fields
,
R.
Firestone
,
B.
Foster
,
A.
Freitas
,
H.
Gallagher
,
L.
Garren
,
H.-J.
Gerber
,
G.
Gerbier
,
T.
Gershon
,
Y.
Gershtein
,
T.
Gherghetta
,
A. A.
Godizov
,
M.
Goodman
,
C.
Grab
,
A. V.
Gritsan
,
C.
Grojean
,
D. E.
Groom
,
M.
Grünewald
,
A.
Gurtu
,
T.
Gutsche
,
H. E.
Haber
,
C.
Hanhart
,
S.
Hashimoto
,
Y.
Hayato
,
K. G.
Hayes
,
A.
Hebecker
,
S.
Heinemeyer
,
B.
Heltsley
,
J. J.
Hernández-Rey
,
J.
Hisano
,
A.
Höcker
,
J.
Holder
,
A.
Holtkamp
,
T.
Hyodo
,
K. D.
Irwin
,
K. F.
Johnson
,
M.
Kado
,
M.
Karliner
,
U. F.
Katz
,
S. R.
Klein
,
E.
Klempt
,
R. V.
Kowalewski
,
F.
Krauss
,
M.
Kreps
,
B.
Krusche
,
Y. V.
Kuyanov
,
Y.
Kwon
,
O.
Lahav
,
J.
Laiho
,
J.
Lesgourgues
,
A.
Liddle
,
Z.
Ligeti
,
C.-J.
Lin
,
C.
Lippmann
,
T. M.
Liss
,
L.
Littenberg
,
K. S.
Lugovsky
,
S. B.
Lugovsky
,
A.
Lusiani
,
Y.
Makida
,
F.
Maltoni
,
T.
Mannel
,
A. V.
Manohar
,
W. J.
Marciano
,
A. D.
Martin
,
A.
Masoni
,
J.
Matthews
,
U.-G.
Meißner
,
D.
Milstead
,
R. E.
Mitchell
,
K.
Mönig
,
P.
Molaro
,
F.
Moortgat
,
M.
Moskovic
,
H.
Murayama
,
M.
Narain
,
P.
Nason
,
S.
Navas
,
M.
Neubert
,
P.
Nevski
,
Y.
Nir
,
K. A.
Olive
,
S.
Pagan Griso
,
J.
Parsons
,
C.
Patrignani
,
J. A.
Peacock
,
M.
Pennington
,
S. T.
Petcov
,
V. A.
Petrov
,
E.
Pianori
,
A.
Piepke
,
A.
Pomarol
,
A.
Quadt
,
J.
Rademacker
,
G.
Raffelt
,
B. N.
Ratcliff
,
P.
Richardson
,
A.
Ringwald
,
S.
Roesler
,
S.
Rolli
,
A.
Romaniouk
,
L. J.
Rosenberg
,
J. L.
Rosner
,
G.
Rybka
,
R. A.
Ryutin
,
C. T.
Sachrajda
,
Y.
Sakai
,
G. P.
Salam
,
S.
Sarkar
,
F.
Sauli
,
O.
Schneider
,
K.
Scholberg
,
A. J.
Schwartz
,
D.
Scott
,
V.
Sharma
,
S. R.
Sharpe
,
T.
Shutt
,
M.
Silari
,
T.
Sjöstrand
,
P.
Skands
,
T.
Skwarnicki
,
J. G.
Smith
,
G. F.
Smoot
,
S.
Spanier
,
H.
Spieler
,
C.
Spiering
,
A.
Stahl
,
S. L.
Stone
,
T.
Sumiyoshi
,
M. J.
Syphers
,
K.
Terashi
,
J.
Terning
,
U.
Thoma
,
R. S.
Thorne
,
L.
Tiator
,
M.
Titov
,
N. P.
Tkachenko
,
N. A.
Törnqvist
,
D. R.
Tovey
,
G.
Valencia
,
R.
Van de Water
,
N.
Varelas
,
G.
Venanzoni
,
L.
Verde
,
M. G.
Vincter
,
P.
Vogel
,
A.
Vogt
,
S. P.
Wakely
,
W.
Walkowiak
,
C. W.
Walter
,
D.
Wands
,
D. R.
Ward
,
M. O.
Wascko
,
G.
Weiglein
,
D. H.
Weinberg
,
E. J.
Weinberg
,
M.
White
,
L. R.
Wiencke
,
S.
Willocq
,
C. G.
Wohl
,
J.
Womersley
,
C. L.
Woody
,
R. L.
Workman
,
W.-M.
Yao
,
G. P.
Zeller
,
O. V.
Zenin
,
R.-Y.
Zhu
,
S.-L.
Zhu
,
F.
Zimmermann
,
P. A.
Zyla
,
J.
Anderson
,
L.
Fuller
,
V. S.
Lugovsky
,
P.
Schaffner
, and
Particle Data Group
, “
Review of particle physics
,”
Phys. Rev. D
98
,
030001
(
2018
).
33.
G.
Saracino
,
F.
Ambrosino
,
L.
Bonechi
,
L.
Cimmino
,
R.
D’Alessandro
,
M.
D’Errico
,
P.
Noli
,
L.
Scognamiglio
, and
P.
Strolin
, “
Applications of muon absorption radiography to the fields of archaeology and civil engineering
,”
Philos. Trans. R. Soc. A: Math. Phys. Eng. Sci.
377
,
20180057
(
2019
).
34.
E. P.
George
, “
Cosmic rays measure overburden of tunnel
,”
Commonw. Eng.
43
,
455
457
(
1955
).
35.
K.
Nagamine
,
M.
Iwasaki
,
K.
Shimomura
, and
K.
Ishida
, “
Method of probing inner-structure of geophysical substance with the horizontal cosmic-ray muons and possible application to volcanic eruption prediction
,”
Nucl. Instrum. Methods Phys. Res. A: Accel. Spectrom. Detect. Assoc. Equip.
356
,
585
595
(
1995
).
36.
H.
Tanaka
,
T.
Nakano
,
S.
Takahashi
,
J.
Yoshida
,
M.
Takeo
,
J.
Oikawa
,
T.
Ohminato
,
Y.
Aoki
,
E.
Koyama
, and
H.
Tsuji
, “
High resolution imaging in the inhomogeneous crust with cosmic-ray muon radiography: The density structure below the volcanic crater floor of Mt. Asama, Japan
,”
Earth Planet. Sci. Lett.
263
,
104
113
(
2007
).
37.
H. K. M.
Tanaka
,
T.
Nakano
,
S.
Takahashi
,
J.
Yoshida
,
H.
Ohshima
,
T.
Maekawa
,
H.
Watanabe
, and
K.
Niwa
, “
Imaging the conduit size of the dome with cosmic-ray muons: The structure beneath Showa-Shinzan lava dome, Japan
,”
Geophys. Res. Lett.
34
,
L22311
, https://doi.org/10.1029/2007GL031389 (
2007
).
38.
H. K. M.
Tanaka
,
T.
Uchida
,
M.
Tanaka
,
H.
Shinohara
, and
H.
Taira
, “
Cosmic-ray muon imaging of magma in a conduit: Degassing process of Satsuma-Iwojima volcano, Japan
,”
Geophys. Res. Lett.
36
,
L01304
, (
2009
).
39.
H. K. M.
Tanaka
,
H.
Taira
,
T.
Uchida
,
M.
Tanaka
,
M.
Takeo
,
T.
Ohminato
,
Y.
Aoki
,
R.
Nishitama
,
D.
Shoji
, and
H.
Tsuiji
, “
Three-dimensional computational axial tomography scan of a volcano with cosmic ray muon radiography
,”
J. Geophys. Res.
115
,
B12332
, https://doi.org/10.1029/2010JB007677 (
2010
).
40.
G.
Ambrosi
,
F.
Ambrosino
,
R.
Battiston
,
A.
Bross
,
S.
Callier
,
F.
Cassese
,
G.
Castellini
,
R.
Ciaranfi
,
F.
Cozzolino
,
R.
D’Alessandro
,
C.
de La Taille
,
G.
Iacobucci
,
A.
Marotta
,
V.
Masone
,
M.
Martini
,
R.
Nishiyama
,
P.
Noli
,
M.
Orazi
,
L.
Parascandolo
,
P.
Parascandolo
,
G.
Passeggio
,
R.
Peluso
,
A.
Pla-Dalmau
,
L.
Raux
,
R.
Rocco
,
P.
Rubinov
,
G.
Saracino
,
G.
Scarpato
,
G.
Sekhniaidze
,
P.
Strolin
,
H.
Tanaka
,
M.
Tanaka
,
P.
Trattino
,
T.
Uchida
, and
I.
Yokoyamao
, “
The MU-RAY project: Volcano radiography with cosmic-ray muons
,”
Nucl. Instrum. Methods Phys. Res. A: Accel. Spectrom. Detect. Assoc. Equip.
628
,
120
123
(
2011
).
41.
N.
Lesparre
,
D.
Gibert
, and
J.
Marteau
, “
Bayesian dual inversion of experimental telescope acceptance and integrated flux for geophysical muon tomography: Dual inversion for cosmic muon tomography
,”
Geophys. J. Int.
188
,
490
497
(
2012
).
42.
R.
Nishiyama
,
Y.
Tanaka
,
S.
Okubo
,
H.
Oshima
,
H. K. M.
Tanaka
, and
T.
Maekawa
, “
Integrated processing of muon radiography and gravity anomaly data toward the realization of high-resolution 3-d density structural analysis of volcanoes: Case study of Showa-Shinzan lava dome, Usu, Japan
,”
J. Geophys. Res.: Solid Earth
119
,
699
710
, https://doi.org/10.1002/2013JB010234 (
2014
).
43.
F.
Ambrosino
,
A.
Anastasio
,
A.
Bross
,
S.
Béné
,
P.
Boivin
,
L.
Bonechi
,
C.
Cârloganu
,
R.
Ciaranfi
,
L.
Cimmino
,
C.
Combaret
,
R.
D’Alessandro
,
S.
Durand
,
F.
Fehr
,
V.
Français
,
F.
Garufi
,
L.
Gailler
,
P.
Labazuy
,
I.
Laktineh
,
J.-F.
Lénat
,
V.
Masone
,
D.
Miallier
,
L.
Mirabito
,
L.
Morel
,
N.
Mori
,
V.
Niess
,
P.
Noli
,
A.
Pla-Dalmau
,
A.
Portal
,
P.
Rubinov
,
G.
Saracino
,
E.
Scarlini
,
P.
Strolin
, and
B.
Vulpescu
, “
Joint measurement of the atmospheric muon flux through the Puy de Dôme volcano with plastic scintillators and resistive plate chambers detectors: Muon flux crossing Puy-de-Dome
,”
J. Geophys. Res.: Solid Earth
120
,
7290
7307
, https://doi.org/10.1002/2015JB011969 (
2015
).
44.
M.
Rosas-Carbajal
,
K.
Jourde
,
J.
Marteau
,
S.
Deroussi
,
J.-C.
Komorowski
, and
D.
Gibert
, “
Three-dimensional density structure of La Soufrière de Guadeloupe lava dome from simultaneous muon radiographies and gravity data: 3-D muon tomography of La Soufrière
,”
Geophys. Res. Lett.
44
,
6743
6751
, (
2017
).
45.
K.
Davis
,
D. W.
Oldenburg
,
V.
Kaminski
,
M.
Pilkington
,
D.
Bryman
,
J.
Bueno
, and
Z.
Liu
, “Joint 3D inversion of muon tomography and gravity data,” in International Workshop on Gravity, Electrical & Magnetic Methods and Their Applications, Beijing, China, 10–13 October 2011, edited by X. Li, Y. Li, and X. Meng (Society of Exploration Geophysicists, Beijing, China, 2011), p. 81.
46.
D.
Bryman
,
J.
Bueno
,
K.
Davis
,
V.
Kaminski
,
Z.
Liu
,
D.
Oldenburg
,
M.
Pilkington
, and
R.
Sawyer
, “Muon geotomography—Bringing new physics to orebody imaging, ’ in Building Exploration Capability for the 21st Century (Society of Economic Geologists, 2014).
47.
D.
Bryman
,
J.
Bueno
, and
J.
Jansen
, “
Blind test of muon geotomography for mineral exploration
,”
ASEG Extend. Abstr.
2015
,
1
3
.
48.
D.
Schouten
and
P.
Ledru
, “
Muon tomography applied to a dense uranium deposit at the McArthur river mine
,”
J. Geophys. Res.: Solid Earth
123
,
8637
8652
, https://doi.org/10.1029/2018JB015626 (
2018
).
49.
D.
Schouten
, “
Muon geotomography: Selected case studies
,”
Philos. Trans. R. Soc. A: Math. Phys. Eng. Sci.
377
,
20180061
(
2019
).
50.
L.
Cimmino
,
G.
Baccani
,
P.
Noli
,
L.
Amato
,
F.
Ambrosino
,
L.
Bonechi
,
M.
Bongi
,
V.
Ciulli
,
R.
D’Alessandro
,
M.
D’Errico
,
S.
Gonzi
,
B.
Melon
,
G.
Minin
,
G.
Saracino
,
L.
Scognamiglio
,
P.
Strolin
, and
L.
Viliani
, “
3D muography for the search of hidden cavities
,”
Sci. Rep.
9
,
2974
(
2019
).
51.
G.
Baccani
,
L.
Bonechi
,
M.
Bongi
,
D.
Brocchini
,
N.
Casagli
,
R.
Ciaranfi
,
L.
Cimmino
,
V.
Ciulli
,
R.
D’Alessandro
,
C.
Ventisette
,
A.
Dini
,
G.
Gigli
,
S.
Gonzi
,
S.
Guideri
,
L.
Lombardi
,
B.
Melon
,
N.
Mori
,
M.
Nocentini
,
P.
Noli
, and
L.
Viliani
, “
Muon radiography of ancient mines: The San Silvestro Archaeo-mining Park (Campiglia Marittima, Tuscany)
,”
Universe
5
,
34
(
2019
).
52.
R.
Nishiyama
,
A.
Ariga
,
T.
Ariga
,
S.
Käser
,
A.
Lechmann
,
D.
Mair
,
P.
Scampoli
,
M.
Vladymyrov
,
A.
Ereditato
, and
F.
Schlunegger
, “
First measurement of ice-bedrock interface of alpine glaciers by cosmic muon radiography
,”
Geophys. Res. Lett.
44
,
6244
6251
, https://doi.org/10.1002/2017GL073599 (
2017
).
53.
J.
Lunn
, “
Cosmic muons reveal the land hidden under ice
,”
Eos
98
(
2017
), see https://eos.org/research-spotlights/cosmic-muons-reveal-the-land-hidden-under-ice.
54.
R.
Nishiyama
,
A.
Ariga
,
T.
Ariga
,
A.
Lechmann
,
D.
Mair
,
C.
Pistillo
,
P.
Scampoli
,
P. G.
Valla
,
M.
Vladymyrov
,
A.
Ereditato
, and
F.
Schlunegger
, “
Bedrock sculpting under an active alpine glacier revealed from cosmic-ray muon radiography
,”
Sci. Rep.
9
,
6970
(
2019
).
55.
L. W.
Alvarez
,
J. A.
Anderson
,
F. E.
Bedwei
,
J.
Burkhard
,
A.
Fakhry
,
A.
Girgis
,
A.
Goneid
,
F.
Hassan
,
D.
Iverson
,
G.
Lynch
,
Z.
Miligy
,
A. H.
Moussa
,
M.
Sharkawi
, and
L.
Yazolino
, “
Search for hidden chambers in the pyramids: The structure of the second pyramid of Giza is determined by cosmic-ray absorption
,”
Science
167
,
832
839
(
1970
).
56.
K.
Morishima
,
M.
Kuno
,
A.
Nishio
,
N.
Kitagawa
,
Y.
Manabe
,
M.
Moto
,
F.
Takasaki
,
H.
Fujii
,
K.
Satoh
,
H.
Kodama
,
K.
Hayashi
,
S.
Odaka
,
S.
Procureur
,
D.
Attié
,
S.
Bouteille
,
D.
Calvet
,
C.
Filosa
,
P.
Magnier
,
I.
Mandjavidze
,
M.
Riallot
,
B.
Marini
,
P.
Gable
,
Y.
Date
,
M.
Sugiura
,
Y.
Elshayeb
,
T.
Elnady
,
M.
Ezzy
,
E.
Guerriero
,
V.
Steiger
,
N.
Serikoff
,
J.-B.
Mouret
,
B.
Charlès
,
H.
Helal
, and
M.
Tayoubi
, “
Discovery of a big void in Khufu’s pyramid by observation of cosmic-ray muons
,”
Nature
552
,
386
390
(
2017
).
57.
X.
Luo
,
Q.
Wang
,
K.
Qin
,
H.
Tian
,
Z.
Fu
,
Y.
Zhao
,
Z.
Shen
,
H.
Liu
,
Y.
Fu
,
G.
Liu
,
K.
Yao
,
X.
Qian
,
J.
Rong
,
W.
Zhang
,
X.
Luo
,
C.
Liu
,
X.
Tian
,
M.
Yu
,
F.
Wu
,
J.
Chen
,
J.
Liu
, and
Z.
Liu
, “
Development and commissioning of a compact cosmic ray muon imaging prototype
,”
Nucl. Instrum. Methods Phys. Res. A: Accel. Spectrom. Detect. Assoc. Equip.
1033
,
166720
(
2022
).
58.
H.
Liu
,
Z.
Shen
,
Z.
Liu
,
C.
Feng
, and
S.
Liu
, “
Development of the readout system for SiPM-scintillator-based muography devices
,”
J. Instrum.
16
,
T06012
(
2021
).
59.
E. V.
Bugaev
,
A.
Misaki
,
V. A.
Naumov
,
T. S.
Sinegovskaya
,
S. I.
Sinegovsky
, and
N.
Takahashi
, “
Atmospheric muon flux at sea level, underground, and underwater
,”
Phys. Rev. D
58
,
054001
(
1998
).
60.
T.
Hebbeker
and
C.
Timmermans
, “
A compilation of high energy atmospheric muon data at sea level
,”
Astropart. Phys.
18
,
107
127
(
2002
).
61.
R. L.
Workman
and
others (Particle Data Group)
, “
Review of particle physics
,”
PTEP
2022
,
083C01
.
62.
R.
Cockett
,
S.
Kang
,
L. J.
Heagy
,
A.
Pidlisecky
, and
D. W.
Oldenburg
, “
SimPEG: An open source framework for simulation and gradient based parameter estimation in geophysical applications
,”
Comput. Geosci.
85
,
142
154
(
2015
).
63.
Y.
Li
and
D. W.
Oldenburg
, “
Fast inversion of large-scale magnetic data using wavelet transforms and a logarithmic barrier method
,”
Geophys. J. Int.
152
,
251
265
(
2003
).
64.
R.
Brun
and
F.
Rademakers
, “
ROOT—An object oriented data analysis framework
,”
Nucl. Instrum. Methods Phys. Res. A
389
,
81
86
(
1997
).
65.
G.
Van Rossum
and
F. L.
Drake
,
Python 3 Reference Manual
(
CreateSpace
,
Scotts Valley, CA
,
2009
).
66.
M. S.
Zhdanov
, “Forward and inverse problems in science and engineering,” in Inverse Theory and Applications in Geophysics, 2nd ed., edited by M. S. Zhdanov (Elsevier, Oxford, 2015), Chap. 1, pp. 3–31.
67.
U.
Ayachit
,
The ParaView Guide: A Parallel Visualization Application
(
Kitware, Inc.
,
Clifton Park, NY
,
2015
).
68.
L.
Lista
, Statistical Methods for Data Analysis in Particle Physics, Lecture Notes in Physics (Springer International Publishing, Cham, 2016), Vol. 909.
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