MuonPi-Wiki - User contributions [en-gb]

Muon

2020-04-17T18:08:35Z

KDort:

A '''muon''' (μ) is an elementary particle with unit electric charge and a mass of about 106 MeV/c2. Muons have a mean lifetime of about 2.2 μs and decay primarily into electrons and neutrinos.

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== Particle properties ==

Muons are elementary particles which interact '''graviationally''', '''electromagnetically''' and '''weakly'''. The particles do not undergo strong interactions, owing to their half-integer spin.
The mass of muons is about 106 MeV/c2, making them about 207 times heavier than electrons.

[[File:Muon Decay.png|thumb|right|Feynman diagram of a muon decaying into two neutrinos and an electron]]

Muons have unit electric charge. Conventionally, muons (μ-) are considered to carry a negative charge, while their anti-matter counterparts (anti-muons or μ+) are positively charged.
The weak interaction mediates the decay of muons. As weak processes can be considered ''slow'' on typical sub-atomic timescales, the muons exhibit a mean lifetime of about 2.2 μs. The most common decay products are electrons and neutrinos.

{| class="wikitable"
|-
| '''Interactions''' || Gravity, Electromagnetic, Weak
|-
| '''Mass''' || 105.6583755(23) MeV/c2
|-
| '''Mean lifetime''' || 2.1969811(22) x 10-6 s
|-
| '''Electric charge''' || 1
|-
| '''Spin''' || 1/2
|}

== Muons in cosmic showers ==

Muons appear in cosmic showers as secondary shower particles. Owing to their finite lifetime t, the mean path of muonic shower particles is limited.

Classically, the mean path s is given by s = ct, assuming that the muons have a velocity close to the speed of light c. This expression yields a mean path of 660 m. Consequently, the large majority of cosmics shower muons would decay before they arrive at the surface of Earth.

However, as the muons propagate with a velocity close to the speed of light, a relativistic correction to this calculation has to be applied. Namely, the mean lifetime has to be '''Lorentz transformed''' to the reference frame of a ''stationary'' observer (stationary with respect to Earth).
The <math> \gamma </math>-factor is given by:

<math>\gamma = \frac{1}{\sqrt{1 - v^2/c^2}}</math>

For a muon travelling close to the speed of light (v ~ 0.9997c) one obtains <math> \gamma \approx 40.83 </math>.
This yields an Eigen time <math> \tau </math> of:

<math> \tau = \gamma t = 40.83 \dot 2.2</math> μs = 90 μs

which effectively yields a longer mean path: <math> \gamma x = 40.83 \dot 660</math> m = 27 km.
This relativistic '''time dilation''' (or equivalently '''length contraction''') enables the muons to reach the surface of the Earth before they decay. Our ability to measure muons on sea level is therefore direct evidence of the relativistic mechanisms that govern the propagation of particles travelling close to the speed of light.

Muon

2020-04-17T18:07:42Z

KDort:

Muon

2020-04-17T18:01:28Z

KDort:

Muon

2020-04-17T17:38:07Z

KDort:

A '''muon''' (μ) is an elementary particle with unit electric charge and a mass of about 106 MeV/c2. Muons have a mean lifetime of about 2.2 μs and decay primarily into electrons and neutrinos.

__TOC__

== Particle properties ==

Muons are elementary particles which interact '''graviationally''', '''electromagnetically''' and '''weakly'''. The particles do not undergo strong interactions, owing to their half-integer spin.
The mass of muons is about 106 MeV/c2, making them about 207 times heavier than electrons.

[[File:Muon Decay.png|thumb|right|Feynman diagram of a muon decaying into two neutrinos and an electron]]

Muons have unit electric charge. Conventionally, muons (μ-) are considered to carry a negative charge, while their anti-matter counterparts (anti-muons or μ+) are positively charged.
The weak interaction mediates the decay of muons. As weak processes can be considered ''slow'' on typical sub-atomic timescales, the muons exhibit a mean lifetime of about 2.2 μs. The most common decay products are electrons and neutrinos.

{| class="wikitable"
|-
| '''Interactions''' || Gravity, Electromagnetic, Weak
|-
| '''Mass''' || 105.6583755(23) MeV/c2
|-
| '''Mean lifetime''' || 2.1969811(22) x 10-6 s
|-
| '''Electric charge''' || 1
|-
| '''Spin''' || 1/2
|}

== Muons in cosmic showers ==

Muons appear in cosmic showers as secondary shower particles. Owing to their finite lifetime t, the mean path of muonic shower particles is limited.

Classically, the mean path s is given by s = ct, assuming that the muons have a velocity close to the speed of light c. This expression yields a mean path of 660 m. Consequently, the large majority of cosmics shower muons would decay before they arrive at the surface of Earth.

However, as the muons propagate with a velocity close to the speed of light, a relativistic correction to this calculation has to be applied. Namely, the mean lifetime has to be '''Lorentz transformed''' to the reference frame of a ''stationary'' observer (stationary with respect to Earth).
The <math> \gamma </math>-factor is given by:
<math>\gamma = \frac{1}{\sqrt{1 - v^2/c^2}}</math>

For a muon travelling close to the speed of light (v ~ 0.9997c) one obtains <math> \gamma \approx 40.83 </math>.
This yields an Eigen time <math> \tau </math> of:
<math> \tau = \gamma t = 40.83 \dot 2.2</math> μs = 90 μs

Muon

2020-04-17T17:33:23Z

KDort:

A '''muon''' (μ) is an elementary particle with unit electric charge and a mass of about 106 MeV/c2. Muons have a mean lifetime of about 2.2 μs and decay primarily into electrons and neutrinos.

__TOC__

== Particle properties ==

Muons are elementary particles which interact '''graviationally''', '''electromagnetically''' and '''weakly'''. The particles do not undergo strong interactions, owing to their half-integer spin.
The mass of muons is about 106 MeV/c2, making them about 207 times heavier than electrons.

[[File:Muon Decay.png|thumb|right|Feynman diagram of a muon decaying into two neutrinos and an electron]]

Muons have unit electric charge. Conventionally, muons (μ-) are considered to carry a negative charge, while their anti-matter counterparts (anti-muons or μ+) are positively charged.
The weak interaction mediates the decay of muons. As weak processes can be considered ''slow'' on typical sub-atomic timescales, the muons exhibit a mean lifetime of about 2.2 μs. The most common decay products are electrons and neutrinos.

{| class="wikitable"
|-
| '''Interactions''' || Gravity, Electromagnetic, Weak
|-
| '''Mass''' || 105.6583755(23) MeV/c2
|-
| '''Mean lifetime''' || 2.1969811(22) x 10-6 s
|-
| '''Electric charge''' || 1
|-
| '''Spin''' || 1/2
|}

== Muons in cosmic showers ==

Muons appear in cosmic showers as secondary shower particles. Owing to their finite lifetime t, the mean path of muonic shower particles is limited.

Classically, the mean path s is given by s = ct, assuming that the muons have a velocity close to the speed of light c. This expression yields a mean path of 660 m. Consequently, the large majority of cosmics shower muons would decay before they arrive at the surface of Earth.

However, as the muons propagate with a velocity close to the speed of light, a relativistic correction to this calculation has to be applied. Namely, the mean lifetime has to be '''Lorentz transformed''' to the reference frame of a ''stationary'' observer (stationary with respect to Earth).

<math>\gamma = \frac{1}{\sqrt{1 - v^2/c^2}}</math>

Muon

2020-04-14T18:35:41Z

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Muon

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Muon

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Muon

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Muon

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Muon

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File:Muon Decay.png

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Main Page

2020-04-10T11:25:26Z

KDort: /* Learn about cosmic radiation */

= The MuonPi Cosmic Detector Project =
The MuonPi Project is a [https://www.raspberrypi.org/ RaspberryPi]-based system using an inexpensive plastic [[Scintillator|scintillator]] + [[Silicon photomultiplier|SiPM]] photo sensor to detect muons from cosmic air showers with a time-stamping accuracy of several tens of nanoseconds utilizing the [https://www.u-blox.com/en/product/neo-m8-series u-blox NEO-M8N GNSS] module's "timemark" feature.

==== Learn about cosmic radiation ====
* Get started with [[Cosmic Rays]], especially [[Muon]]s
* [https://www.weltderphysik.de/mediathek/podcast/kosmische-strahlung/ "Kosmische Strahlung"] Podcast (in German) on [https://www.weltderphysik.de weltderphysik.de]
* [https://www.weltderphysik.de/thema/bmbf/astro-undastroteilchenphysik/der-kosmischen-strahlung-auf-der-spur/ "Der kosmischen Strahlung auf der Spur"] article (in German) on [https://www.weltderphysik.de weltderphysik.de]
* [https://www.weltderphysik.de/gebiet/universum/news/2017/kosmische-teilchen-mit-extragalaktischem-ursprung/ "Kosmische Teilchen mit extragalaktischem Ursprung"] article (in German) on [https://www.weltderphysik.de weltderphysik.de]

==== Learn about the detectors ====
* Basics of [[Scintillator]]s
* Find out about [[Silicon photomultiplier]]s
* How the [[The Detector|detector]] works

= The Hardware =

=== SiPM PCB ===
The SiPM photo sensor which detects the dim light generated inside the scintillation detector is mounted on a small [[Sipm_board|SiPM board]]. Different numbers of SiPMs and read-out configurations can be realized through its flexible design.

=== Preamplifier ===
The [[preamp|preamplifier]] is located in close vicinity to the [[sipm_board|SiPM photodetector board]] and amplifies the weak signals for transmission to the [[muonpi_board|MuonPi]] board, where they are further processed and evaluated.

=== The MuonPi-Board ===

The main signal processing, voltage generation and parameter monitoring and adjustment is done on the Raspberry Pi plug-on [[muonpi_board|MuonPi Board]].

= The Software =

= Admin Area =

Useful [[resources]] for admins.

= Other languages =

* [[Main Page/de]]

= About this Wiki =
* How to edit? [[help for creators]]
* [http://www.mediawiki.org/wiki/Manual:Configuration_settings List of config variables]
* [http://www.mediawiki.org/wiki/Manual:FAQ MediaWiki-FAQ]
* [https://lists.wikimedia.org/mailman/listinfo/mediawiki-announce Mailing list of new MediaWiki version announcements]

----
Sandbox page for testing/playing :
* [[Sandbox]]

Muon

2020-04-10T11:24:24Z

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Muon

2020-04-10T11:23:50Z

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Muon

2020-04-10T11:16:50Z

KDort: /* Muons in cosmic showers */

Muon

2020-04-10T11:15:12Z

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Muon

2020-04-10T11:05:16Z

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Muon

2020-04-10T10:29:35Z

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Muon

2020-04-10T10:19:24Z

KDort:

Muon

2020-04-10T10:10:07Z

KDort:

A '''muon''' (μ) is an elementary particle with unit electric charge and a mass of about 106 MeV/c2

{| class="wikitable"
|-
| Interactions || Gravity, Electromagnetic, Weak
|-
| Mass || 105.6583755(23) MeV/c2
|-
| Mean lifetime || 2.1969811(22) x 10-6 s
|-
| Electric charge || 1
|-
| Spin || 1/2
|}

Muon

2020-04-10T10:09:23Z

KDort:

A '''muon''' (μ) is an elementary particle with unit electric charge and a mass of about 106 MeV/c2

{|
|-
| Interactions || Gravity, Electromagnetic, Weak
|-
| Mass || 105.6583755(23) MeV/c2
|-
| Mean lifetime || 2.1969811(22) x 10-6 s
|-
| Electric charge || 1
|-
| Spin || 1/2
|}

Muon

2020-04-10T10:07:24Z

KDort: Created page with " A '''muon''' (μ) is an elementary particle with unit electric charge and a mass of about 106 MeV/c2"

A '''muon''' (μ) is an elementary particle with unit electric charge and a mass of about 106 MeV/c2

Cosmic Rays

2020-04-10T10:05:26Z

KDort:

'''Cosmic rays ''' are highly energetic particles which originate from extraterrestrial sources. A distinction between '''soft cosmic radiation''' stemming mainly from our sun and '''hard cosmic radiation''' produced outside our solar system can be made. When interacting with particles in the earth's atmosphere, '''primary cosmic rays''' can induce a '''high energy shower cascade''' yielding a multitude of newly produced particles.

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== Composition ==
[[File:Energy spectrum primary cosmic rays.png|0.1px|thumb|right|Energy spectrum of primary cosmic radiation]]

Primary cosmic consists of about 90% of protons, about 9% of helium nuclei and 1% of heavier nuclei. The precise composition depends on the considered energy range. The energy distribution of primary cosmic particles, as shown o the plot on the right, has a most probable value of about 300 MeV (3 x 106 eV) and drops sharply for increasing energies. However, cosmic rays with energies up to 3 x 1020 eV (~ 50 J) have been observed.

[[File:PIA16938-RadiationSources-InterplanetarySpace.jpg|thumb|left|Cosmic rays produced in the sun are deflected by the Earth's magnetic field]]

As the energy of a primary cosmic particle hints at its origin, a classification in '''soft cosmic radiation''' with kinetic energies up to several hundred MeV and '''hard cosmic radiation''' is done. Soft cosmic radiation originates from the sun. The relatively low energy of these particles allows for a deflection due to the Earth's magnetic field. The deflected particles are steered towards the magnetic poles where they interact with the atmosphere which can be seen as polar lights.

== Cosmic ray showers ==
The interaction of primary cosmic rays with an atmosphere yields a plethora of secondary particles. AS these secondary particles decay themselves, they give rise to tertiary particles decaying into even more particles. Ultimately, a primary cosmic ray triggers a multiplication process yielding a '''shower''' of particles. The extension of the shower heavily influenced by the energy and type of the primary particle.

[[File:Cosmic shower.png|thumb|left|Schematic representation of a cosmic ray shower. The interaction of the primary proton with the atmosphere gives rise to secondary particles. ]]

The most prevalent particle species in the showers are electrons, photons, protons, neutrons, pions and muons. While the former four can be considered inherently stable on the timescales relevant for a cosmic shower formation, pions and muons have a finite life-time. Owing to [[relativistic effects]], the detection of muons on the surface of Earth is nonetheless possible. Measuring these secondary muons paves the way to reconstruct properties of the cosmics shower itself as well as the primary particle.

Cosmic Rays

2020-04-10T09:52:37Z

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Cosmic Rays

2020-04-10T09:51:45Z

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'''Cosmic rays ''' are highly energetic particles which originate from extraterrestrial sources. A distinction between '''soft cosmic radiation''' stemming mainly from our sun and '''hard cosmic radiation''' produced outside our solar system can be made. When interacting with particles in the earth's atmosphere, '''primary cosmic rays''' can induce a '''high energy shower cascade''' yielding a multitude of newly produced particles.

__TOC__

== Composition ==
[[File:Energy spectrum primary cosmic rays.png|0.1px|thumb|right|Energy spectrum of primary cosmic radiation]]

Primary cosmic consists of about 90% of protons, about 9% of helium nuclei and 1% of heavier nuclei. The precise composition depends on the considered energy range. The energy distribution of primary cosmic particles, as shown o the plot on the right, has a most probable value of about 300 MeV (3 x 106 eV) and drops sharply for increasing energies. However, cosmic rays with energies up to 3 x 1020 eV (~ 50 J) have been observed.

[[File:PIA16938-RadiationSources-InterplanetarySpace.jpg|thumb|right|Cosmic rays produced in the sun are deflected by the Earth's magnetic field]]

As the energy of a primary cosmic particle hints at its origin, a classification in '''soft cosmic radiation''' with kinetic energies up to several hundred MeV and '''hard cosmic radiation''' is done. Soft cosmic radiation originates from the sun. The relatively low energy of these particles allows for a deflection due to the Earth's magnetic field. The deflected particles are steered towards the magnetic poles where they interact with the atmosphere which can be seen as polar lights.

== Cosmic ray showers ==
The interaction of primary cosmic rays with an atmosphere yields a plethora of secondary particles. AS these secondary particles decay themselves, they give rise to tertiary particles decaying into even more particles. Ultimately, a primary cosmic ray triggers a multiplication process yielding a '''shower''' of particles. The extension of the shower heavily influenced by the energy and type of the primary particle.

[[File:Cosmic shower.png|frameless|right|Schematic representation of a cosmic ray shower. The interaction of the primary proton with the atmosphere gives rise to secondary particles. ]]

File:Cosmic shower.png

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Cosmic Rays

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Cosmic Rays

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Cosmic Rays

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Cosmic Rays

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Cosmic Rays

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Cosmic Rays

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Cosmic Rays

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Cosmic Rays

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Cosmic Rays

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Cosmic Rays

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Cosmic Rays

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Cosmic Rays

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File:Energy spectrum primary cosmic rays.png

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Cosmic Rays

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Silicon photomultiplier

2020-04-04T15:59:25Z

KDort: Undo revision 46 by KDort (talk)

'''Silicon photomultipliers''' (abbrev. '''SiPM''') are photon-sensitive detectors operating as '''Single-photon avalanche diodes''' ('''SPAD''').

__TOC__

== Principle of Photodiodes ==
A SiPM detector is formed by a pixelated matrix of photodiodes. Each photodiode consists of a junction of positively and negatively doped silicon ('''p-n junction'''). A depleted region which is devoid of free charge carriers is formed in between the differently doped silicon materials. By applying a reverse-voltage to the photodiodes, the depleted region can be enlarged to extend through the entire sensor.
The passage of ionizing radiation through a photodiode creates electron-hole pairs. These liberated charge carriers are accelerated by the electric field in the depleted region towards the anode (holes) or cathode (electrons).

== The Geiger Mode ==
[[File:Iv characteristic diode.png|frame|right|Current-Voltage characteristic of a diode. A SiPM operates in the Breakdown regime.]]

If the reverse-voltage is high enough to exceed the breakdown voltage of the p-n junction, the diode is said to operate in '''Geiger-mode'''. The energy of a single charge carrier accelerated by the electric field is sufficient to create additional electron-hole pairs which in turn liberate even more charge carriers. Ultimately, the multiplication process can lead to a self-sustaining avalanche.
== SiPM Photosensors ==

When combining a multitude of photodiodes designed and operated as described in the previous sections, a SiPM detector is formed. The size of individual pixels (or diodes) ranges from 10 to 100 micrometres.

Silicon photomultiplier

2020-04-04T15:58:43Z

KDort:

== Principle of Photodiodes ==
A SiPM detector is formed by a pixelated matrix of photodiodes. Each photodiode consists of a junction of positively and negatively doped silicon ('''p-n junction'''). A depleted region which is devoid of free charge carriers is formed in between the differently doped silicon materials. By applying a reverse-voltage to the photodiodes, the depleted region can be enlarged to extend through the entire sensor.
The passage of ionizing radiation through a photodiode creates electron-hole pairs. These liberated charge carriers are accelerated by the electric field in the depleted region towards the anode (holes) or cathode (electrons).

== The Geiger Mode ==
[[File:Iv characteristic diode.png|frame|right|Current-Voltage characteristic of a diode. A SiPM operates in the Breakdown regime.]]

If the reverse-voltage is high enough to exceed the breakdown voltage of the p-n junction, the diode is said to operate in '''Geiger-mode'''. The energy of a single charge carrier accelerated by the electric field is sufficient to create additional electron-hole pairs which in turn liberate even more charge carriers. Ultimately, the multiplication process can lead to a self-sustaining avalanche.

== SiPM Photosensors ==

When combining a multitude of photodiodes designed and operated as described in the previous sections, a SiPM detector is formed. The size of individual pixels (or diodes) ranges from 10 to 100 micrometres.

Silicon photomultiplier

2020-04-04T15:50:53Z

KDort:

Silicon photomultiplier

2020-04-04T15:49:34Z

KDort:

'''Silicon photomultipliers''' (abbrev. '''SiPM''') are photon-sensitive detectors operating as '''Single-photon avalanche diodes''' ('''SPAD''').

__TOC__

== Principle of Photodiodes ==
A SiPM detector is formed by a pixelated matrix of photodiodes. Each photodiode consists of a junction of positively and negatively doped silicon ('''p-n junction'''). A depleted region which is devoid of free charge carriers is formed in between the differently doped silicon materials. By applying a reverse-voltage to the photodiodes, the depleted region can be enlarged to extend through the entire sensor.

[[File:Iv characteristic diode.png|frame|right|Current-Voltage characteristic of a diode. A SiPM operates in the Breakdown regime.]]

The passage of ionizing radiation through a photodiode creates electron-hole pairs. These liberated charge carriers are accelerated by the electric field in the depleted region towards the anode (holes) or cathode (electrons). If the reverse-voltage is high enough to exceed the breakdown voltage of the p-n junction, the diode is said to operate in '''Geiger-mode'''. The energy of a single charge carrier accelerated by the electric field is sufficient to create additional electron-hole pairs which in turn liberate even more charge carriers. Ultimately, the multiplication process can lead to a self-sustaining avalanche.

Silicon photomultiplier

2020-04-04T15:48:58Z

KDort:

'''Silicon photomultipliers''' (abbrev. '''SiPM''') are photon-sensitive detectors operating as '''Single-photon avalanche diodes''' ('''SPAD''').

__TOC__

== Principle of Photodiodes ==
A SiPM detector is formed by a pixelated matrix of photodiodes. Each photodiode consists of a junction of positively and negatively doped silicon ('''p-n junction'''). A depleted region which is devoid of free charge carriers is formed in between the differently doped silicon materials. By applying a reverse-voltage to the photodiodes, the depleted region can be enlarged to extend through the entire sensor.

[[File:Iv characteristic diode.png|thumb|right|Current-Voltage characteristic of a diode. A SiPM operates in the Breakdown regime.]]

The passage of ionizing radiation through a photodiode creates electron-hole pairs. These liberated charge carriers are accelerated by the electric field in the depleted region towards the anode (holes) or cathode (electrons). If the reverse-voltage is high enough to exceed the breakdown voltage of the p-n junction, the diode is said to operate in '''Geiger-mode'''. The energy of a single charge carrier accelerated by the electric field is sufficient to create additional electron-hole pairs which in turn liberate even more charge carriers. Ultimately, the multiplication process can lead to a self-sustaining avalanche.

Silicon photomultiplier

2020-04-04T15:47:44Z

KDort:

'''Silicon photomultipliers''' (abbrev. '''SiPM''') are photon-sensitive detectors operating as '''Single-photon avalanche diodes''' ('''SPAD''').

__TOC__

== Principle of Photodiodes ==
A SiPM detector is formed by a pixelated matrix of photodiodes. Each photodiode consists of a junction of positively and negatively doped silicon ('''p-n junction'''). A depleted region which is devoid of free charge carriers is formed in between the differently doped silicon materials. By applying a reverse-voltage to the photodiodes, the depleted region can be enlarged to extend through the entire sensor.

<gallery>
iv_characteristic_diode.png|Current-Voltage characteristic of a diode. A SiPM operates in the Breakdown regime.
</gallery>

The passage of ionizing radiation through a photodiode creates electron-hole pairs. These liberated charge carriers are accelerated by the electric field in the depleted region towards the anode (holes) or cathode (electrons). If the reverse-voltage is high enough to exceed the breakdown voltage of the p-n junction, the diode is said to operate in '''Geiger-mode'''. The energy of a single charge carrier accelerated by the electric field is sufficient to create additional electron-hole pairs which in turn liberate even more charge carriers. Ultimately, the multiplication process can lead to a self-sustaining avalanche.

File:Iv characteristic diode.png

2020-04-04T15:46:36Z

KDort:

Silicon photomultiplier

2020-04-04T15:44:10Z

KDort:

'''Silicon photomultipliers''' (abbrev. '''SiPM''') are photon-sensitive detectors operating as '''Single-photon avalanche diodes''' ('''SPAD''').

__TOC__

== Principle of Photodiodes ==
A SiPM detector is formed by a pixelated matrix of photodiodes. Each photodiode consists of a junction of positively and negatively doped silicon ('''p-n junction'''). A depleted region which is devoid of free charge carriers is formed in between the differently doped silicon materials. By applying a reverse-voltage to the photodiodes, the depleted region can be enlarged to extend through the entire sensor.

The passage of ionizing radiation through a photodiode creates electron-hole pairs. These liberated charge carriers are accelerated by the electric field in the depleted region towards the anode (holes) or cathode (electrons). If the reverse-voltage is high enough to exceed the breakdown voltage of the p-n junction, the diode is said to operate in '''Geiger-mode'''. The energy of a single charge carrier accelerated by the electric field is sufficient to create additional electron-hole pairs which in turn liberate even more charge carriers. Ultimately, the multiplication process can lead to a self-sustaining avalanche.

Main Page

2020-04-04T08:27:46Z

KDort:

Wiki page of the MuonPi project. 
[[help for creators]]

==== Learn about cosmic radition ====
* Get started with [[Cosmic Rays]]
* Other Link

==== Learn about the detectors ====
* Basics of [[Scintillator]]s
* Find out about [[Silicon photomultiplier]]s