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Monopole Flux $-$ Cosmic Ray Searches

``Caty'' in the charge column indicates a search for monopole-catalyzed nucleon decay.

FLUX (cm${}^{-2}$sr${}^{-1}$s${}^{-1}$)

MASS ${\mathrm {(GeV)}}$

CHG ${\mathrm {(\mathit g)}}$

COMMENTS ${\mathrm {(\beta = \mathit v/\mathit c)}}$

DOCUMENT ID

TECN

$ \text{<2E-19} $

$1$

0.86$<\beta <$0.995

ICCB

$ \text{<2E-14} $

$>5E8$

6E-4$<{{\mathit \beta}}<$5E-3

NOVA

$ \text{<1E-17} $

Caty

1E-5 $<\beta <$1E-3

BAIK

$ \text{<1.5E-18} $

$1$

$\beta >$0.6

ANTR

$ \text{<2.5E-21} $

$1$

1E8$<\gamma <$1E13

AUGE

$ \text{<1.55E-18} $

$\beta >$0.51

ICCB

$ \text{<1E-17} $

Caty

1E-3$<\beta <$1E-2

ICCB

$ \text{<3E-18} $

$1$

$\beta >$0.8

ICCB

$ \text{<1.3E-17} $

$1$

$\beta >$0.625

ADRIAN-MARTIN..

ANTR

$ \text{<6E-28} $

$<$1E17

Caty

1E-5$<\beta <$0.04

SKAM

$ \bf{\text{<1E-19}} $

$\bf{1}$

$\bf{\gamma >1E10}$

ANIT

$ \text{<3.8E-17} $

$1$

$\beta >$0.76

ICCB

$ \text{<1.3E-15} $

1E4$<M<$5E13

$1$

$\beta >$0.05

PLAS

$ \text{<0.65E-15} $

$>$5E13

$1$

$\beta >$0.05

PLAS

$ \bf{\text{<1E-18}} $

$\bf{1}$

$\bf{\gamma >1 E8}$

RICE

$ \bf{\text{<1.4E-16}} $

$\bf{1}$

$\bf{1.1E-4<\beta <1}$

MCRO

$ \text{<3E-16} $

Caty

1.1E$-4<\beta <5E-3$

MCRO

$ \text{<1.5E-15} $

$1$

5E$-3<\beta <0.99$

MCRO

$ \text{<1E-15} $

$1$

$1.1 \times 10^{-4} - 0.1$

MCRO

$ \text{<5.6E-15} $

$1$

($0.18 - 3.0)E-3$

MCRO

$ \text{<2.7E-15} $

Caty

$\beta $ $\sim{}1 \times 10^{-3}$

IMB

$ \text{<8.7E-15} $

$1$

$>2.E-3$

SOUD

$ \text{<4.4E-12} $

$1$

all $\beta $

INDU

$ \text{<7.2E-13} $

$1$

all $\beta $

INDU

$ \text{<3.7E-15} $

$>$E12

$1$

$\beta =1.E-4$

PLAS

$ \text{<3.2E-16} $

$>$E10

$1$

$\beta >0.05$

PLAS

$ \text{<3.2E-16} $

$>E10-$E12

2,3

PLAS

$ \text{<3.8E-13} $

$1$

all $\beta $

INDU

$ \text{<5.E-16} $

Caty

$\beta <1.E-3$

CHER

$ \text{<1.8E-14} $

$1$

$\beta >1.1E-4$

HEPT

$ \text{<1E-18} $

3.E$-4<\beta <1.5E-3$

MICA

$ \text{<7.2E-13} $

$1$

all $\beta $

INDU

$ \text{<5.E-12} $

$>$E7

$1$

3.E$-4<\beta <5.E-3$

CNTR

$ \text{<1.E-13} $

Caty

1.E$-5<\beta <$1

SOUD

$ \text{<1.E-10} $

$1$

all $\beta $

INDU

$ \text{<2.E-13} $

1.E$-4<\beta <6.E-4$

HEPT

$ \text{<2.E-14} $

4.E$-5<\beta <2.E-4$

PLAS

$ \text{<2.E-14} $

1.E$-3<\beta <$1

PLAS

$ \text{<5.E-14} $

9.E$-4<\beta <1.E-2$

CNTR

$ \text{<2.E-13} $

4.E$-4<\beta <$1

CNTR

$ \text{<5.E-14} $

$1$

all $\beta $

INDU

$ \text{<5.E-12} $

$1$

INDU

$ \text{<1.E-13} $

$1$

7.E$-4<\beta $

CNTR

$ \text{<7.E-11} $

$1$

all $\beta $

INDU

$ \text{<1.E-18} $

4.E$-4<\beta <1.E-3$

MICA

$ \text{<5.E-12} $

$1$

INDU

$ \text{<6.E-12} $

$1$

INDU

$ \text{<6.E-10} $

$1$

INDU

$ \text{<3.E-15} $

Caty

5.E$-5{}\leq{}\beta {}\leq{}1.E-3$

KAMI

$ \text{<2.E-21} $

Caty

$\beta <1.E-3$

KAMI

$ \text{<3.E-15} $

Caty

1.E$-3<\beta <1.E-1$

CNTR

$ \text{<5.E-12} $

$1$

1.E$-4<\beta <$1

NUSX

$ \text{<7.E-12} $

$1$

INDU

$ \text{<7.E-13} $

$1$

3.E$-4<\beta $

CNTR

$ \text{<2.E-12} $

$1$

3.E$-4<\beta <1.E-1$

CNTR

$ \text{<6.E-13} $

$1$

5.E$-4<\beta <$1

CNTR

$ \text{<2.E-14} $

1.E$-3<\beta $

CNTR

$ \text{<4.E-13} $

$1$

6.E$-4<\beta <2.E-3$

CNTR

$ \text{<1.E-16} $

3.E$-4<\beta <1.E-3$

MICA

$ \text{<1.E-13} $

$1$

1.E$-4<\beta $

PLAS

$ \text{<4.E-13} $

$1$

6.E$-4<\beta <2.E-3$

CNTR

$ $

EMUL

$ \text{<4.E-13} $

$1$

1.E$-2<\beta <1.E-3$

CNTR

$ \text{<1.E-12} $

$1$

7.E$-3<\beta <$1

PLAS

$ \text{<3.E-13} $

$1$

1.E$-3<\beta <4.E-1$

CNTR

$ \text{<3.E-12} $

Caty

5.E$-4<\beta <5.E-2$

CNTR

$ \text{<4.E-11} $

$1$

INDU

$ \text{<5.E-15} $

$1$

1.E$-2<\beta <$1

PLAS

$ \text{<8.E-15} $

Caty

1.E$-4<\beta <1.E-1$

IMB

$ \text{<5.E-12} $

$1$

1.E$-4<\beta <3.E-2$

CNTR

$ \text{<2.E-12} $

6.E$-4<\beta <$1

CNTR

$ \text{<1.E-13} $

$1$

$\beta =3.E-3$

CNTR

$ \text{<2.E-12} $

$1$

7.E$-3<\beta <6.E-1$

CNTR

$ \text{6.E-10} $

$1$

all $\beta $

INDU

$ \text{<2.E-11} $

1.E$-2<\beta <1.E-1$

CNTR

$ \text{<2.E-15} $

concentrator

PLAS

$ \text{<1.E-13} $

>1

1.E$-3<\beta $

PLAS

$ \text{<5.E-11} $

$<$E17

3.E$-4<\beta <1.E-3$

CNTR

$ \text{<2.E-11} $

concentrator

PLAS

$ \text{1.E-1} $

>200

$2$

PLAS

$ \text{<2.E-13} $

>2

PLAS

$ \text{<1.E-19} $

>2

obsidian, mica

PLAS

$ \text{<5.E-15} $

<15

<3

concentrator

ELEC

$ \text{<2.E-11} $

$<1-$3

concentrator

EMUL

¹	ABBASI 2022 search was based on Cherenkov light detection in an array of optical modules in the Antarctic ice cap. Limits are speed-dependent.

²	ACERO 2021 employ NOvA experiment to set reported 90$\%$ CL upper limit on the cosmic monopoles flux for velocity $6 \times 10^{-4}$ $<$ ${{\mathit \beta}}$ $<$ $5 \times 10^{-3}$ and mass $>$ $5 \times 10^{8}$ GeV.

³	GAPONENKO 2021 use data of NT200 two-year operation at Baikal to give speed-dependent limits for different assumed catalysis cross sections. Reported limit is for ${{\mathit \sigma}}$ = 10 mb.

⁴	ALBERT 2017 limits were estimated using a Cherenkov light in an array of optical modules under the Mediterranean Sea. The limits are for MM masses between $10^{10}$ and $10^{14}$ GeV. The limits are speed-dependent.

⁵	AAB 2016 search was made with a set of telescopes sampling the longitudinal profile of fluorescence light emitted by extensive air showers. Limits are speed dependent.

⁶	AARTSEN 2016B was based on a Cherenkov signature in an array of optical modules which were sunk in the Antarctic ice cap. Limits are speed-dependent.

⁷

Beyond the monopole speed, the limits of AARTSEN 2014 depend on the catalysis cross section ($\sigma $) which corresponds to the monopole radiating $\hat{{\mathit l}}$ times the light per track length compared to the Cherenkov light from a single electrically charged, relativistic particle. The values quoted here correspond to $\sigma $ = 1 barn or $\hat{{\mathit l}}$ = 30.

⁸	ABBASI 2013 and ABBASI 2010A were based on a Cherenkov signature in an array of optical modules which were sunk in the Antarctic ice cap. Limits are speed-dependent.

⁹	ADRIAN-MARTINEZ 2012A measurements were based on a Cherenkov signature in an underwater telescope in the Western Mediterranean Sea. Limits are speed-dependent.

¹⁰	The limits from UENO 2012 depend on the monopole speed and are also sensitive to assumed values of monopole mass and the catalysis cross section.

¹¹	HOGAN 2008 and DETRIXHE 2011 limits on relativistic monopoles are based on nonobservation of radio Cherenkov signals at the South Pole. Limits are speed-dependent.

¹²

BALESTRA 2008 exposed of nuclear track detector modules totaling 400 m${}^{2}$ for 4 years at the Chacaltaya Laboratory (5230 m) in search for intermediate-mass monopoles with $\beta >$ 0.05. The analysis is mainly based on three CR39 modules. For M $>5 \times 10^{13}$ GeV there can be upward-going monopoles as well, hence the flux limit is half that obtained for less massive monopoles. Previous experiments (e.g. MACRO and OHYA (ORITO 1991)) had set limits only for M $>$ $1 \times 10^{9}$ GeV.

¹³

AMBROSIO 2002B direct search final result for $\mathit m{}\geq{}10^{17}~$GeV, based upon 4.2 to 9.5 years of running, depending upon the subsystem. Limit with CR39 track-etch detector extends the limit from $\beta =4 \times 10^{-5}$ ($3.1 \times 10^{-16}~$cm${}^{-2}~$sr${}^{-1}~$s${}^{-1}$) to $\beta $= $1 \times 10^{-4}$ ($2.1 \times 10^{-16}~$cm${}^{-2}~$sr${}^{-1}~$s${}^{-1}$). Limit curve in paper is piecewise continuous due to different detection techniques for different $\beta $ ranges.

¹⁴

AMBROSIO 2002C limit for catalysis of nucleon decay with catalysis cross section of $\approx{}~1~$mb. The flux limit increases by $\sim{}$3 at the higher ${{\mathit \beta}}$ limit, and increases to $1 \times 10^{-14}~$cm${}^{-2}~$sr${}^{-1}~$s${}^{-1}$ if the catalysis cross section is 0.01$~$mb. Based upon 71193$~$hr of data with the streamer detector, with an acceptance of 4250$~$m${}^{2}~$sr.

¹⁵	AMBROSIO 2002D result for ``more than two years of data.'' Ionization search using several subsystems. Limit curve as a function of $\beta $ not given. Included in AMBROSIO 2002B.

¹⁶

AMBROSIO 1997 global MACRO 90$\%$CL is $0.78 \times 10^{-15}$ at $\beta =1.1 \times 10^{-4}$, goes through a minimum at $0.61 \times 10^{-15}$ near $\beta =(1.1 - 2.7){\times }10^{-3}$, then rises to $0.84 \times 10^{-15}$ at $\beta =0.1$. The global limit in this region is below the Parker bound at $10^{-15}$. Less stringent limits are established for $4 \times 10^{-5}<\beta <1 \times 10^{-4}$. Limits set by various triggers and different subdetectors are given in the paper. All limits assume a catalysis cross section smaller than a few $~$mb.

¹⁷

AHLEN 1994 limit for dyons extends down to $\beta =0.9E-4$ and a limit of $1.3E-14$ extends to $\beta $ = $0.8E-4$. Also see comment by PRICE 1994 and reply of BARISH 1994. One loophole in the AHLEN 1994 result is that in the case of monopoles catalyzing nucleon decay, relativistic particles could veto the events. See AMBROSIO 1997 for additional results.

¹⁸	Catalysis of nucleon decay; sensitive to assumed catalysis cross section.

¹⁹	ORITO 1991 limits are functions of velocity. Lowest limits are given here.

²⁰	Used DKMPR mechanism and Penning effect.

²¹	Assumes monopole attaches fermion nucleus.

²²	Limit from combining data of CAPLIN 1986, BERMON 1985, INCANDELA 1984, and CABRERA 1983. For a discussion of controversy about CAPLIN 1986 observed event, see GUY 1987. Also see SCHOUTEN 1987.

²³	Based on lack of high- energy solar neutrinos from catalysis in the sun.

²⁴	Anomalous long-range $\alpha $ (${}^{4}\mathrm {He}$) tracks.

²⁵	CABRERA 1982 candidate event has single Dirac charge within $\pm5\%$.

²⁶	ALVAREZ 1975, FLEISCHER 1975, and FRIEDLANDER 1975 explain as fragmenting nucleus. EBERHARD 1975 and ROSS 1976 discuss conflict with other experiments. HAGSTROM 1977 reinterprets as antinucleus. PRICE 1978 reassesses.

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