Belle II experiment: Difference between revisions

Coordinates: 36°9′28″N 140°4′30″E / 36.15778°N 140.07500°E / 36.15778; 140.07500
From Wikipedia, the free encyclopedia
Browse history interactively
← Previous editNext edit →
Content deleted Content added
VisualWikitext
Elimik31 (talk | contribs)
97 edits
m Grammar fixes and small typgraphical fixes like inserting nbsps
Elimik31 (talk | contribs)
97 edits
m Link to resistive plate chambers article, remove unused abbreviation
Line 5: Line 5:


== Detector upgrade ==
== Detector upgrade ==
Much of the original Belle detector has been upgraded<ref name=":1">{{cite arxiv|last=Abe|first=T.|display-authors=etal|date=October 2010|title=Belle II Technical Design Report|eprint=1011.0352|class=physics.ins-det}}</ref> to cope with the higher instantaneous luminosity provided by the SuperKEKB accelerator.<ref name=":0" /> Close to the beam pipe, the two innermost layers of Belle's silicon vertex detector have been replaced by a depleted [[Field-effect transistor|field effect transistor]] (DEPFET) pixel detector, and a larger silicon vertex detector.<ref name=":1" /><ref>{{Cite conference |last=Casarosa |first=Giulia |year=2015 |chapter=Inner tracking devices at the Belle II experiment |chapter-url=https://inspirehep.net/record/1430598 |title=Proceedings, 2015 European Physical Society Conference on High Energy Physics (EPS-HEP 2015) : Vienna, Austria, July 22-29, 2015 |page=255}}</ref> A larger central tracking system, a [[Wire chamber|wire drift chamber]], has been installed.<ref name=":1" /> Two new particle identification systems have been installed in the forward endcap (consisting of an [[aerogel]] [[ring-imaging Cherenkov detector]])<ref name=":1" /><ref>{{Cite journal |last=Nishida |first=S. |display-authors=etal |year=2014 |title=Aerogel RICH for the Belle II forward PID |journal=[[Nuclear Instruments and Methods in Physics Research Section A]] |volume=766 |pages=28–31 |bibcode=2014NIMPA.766...28N |doi=10.1016/j.nima.2014.06.061}}</ref> and in the barrel (consisting of quartz bars utilising [[Total internal reflection|totally internally reflected]] [[Cherenkov radiation|Cherenkov]] photons and measuring the time of propagation).<ref name=":1" /><ref>{{Cite journal |last=Inami |first=Kenji |year=2014 |title=TOP counter for particle identification at the Belle II experiment |journal=[[Nuclear Instruments and Methods in Physics Research Section A]] |volume=766 |pages=5–8 |bibcode=2014NIMPA.766....5I |doi=10.1016/j.nima.2014.07.006}}</ref> The original [[Caesium iodide|CsI]]([[Thallium|Tl]]) electromagnetic [[Calorimeter (particle physics)|calorimeter]] has been re-used (a new pure CsI calorimeter is being designed for the forward endcap<ref name=":2">{{Cite journal |last=Manoni |first=E. |display-authors=etal |year=2017 |title=The upgrade of the Belle II forward calorimeter |journal=[[Nuclear Instruments and Methods in Physics Research Section A]] |volume=845 |pages=524–527 |bibcode=2017NIMPA.845..524M |doi=10.1016/j.nima.2016.06.074}}</ref> to be installed at a later stage<ref name=":2" /><ref>{{Cite web |url=http://belle2.jp/electromagnetic-calorimeter/ |title=Electromagnetic Calorimeter {{!}} Belle{{nbsp}}II Experiment |website=belle2.jp |access-date=2017-05-07}}</ref>). The calorimeter readout electronics have been upgraded.<ref name=":1" /> Finally, scintillators have been installed in the endcaps and inner layers of Belle's {{Subatomic Particle|K-long0|link=yes}} and muon detector, the original resistive plate chambers (RPCs) from Belle are reused in the outer layers of the barrel.<ref name=":1" /><ref>{{Cite journal |last=Aushev |first=T. |display-authors=etal |year=2015 |title=A scintillator based endcap K<sub>L</sub> and muon detector for the Belle II experiment |journal=[[Nuclear Instruments and Methods in Physics Research Section A]] |volume=789 |pages=134–142 |bibcode=2015NIMPA.789..134A |doi=10.1016/j.nima.2015.03.060|arxiv = 1406.3267 |s2cid=118613296 }}</ref>
Much of the original Belle detector has been upgraded<ref name=":1">{{cite arxiv|last=Abe|first=T.|display-authors=etal|date=October 2010|title=Belle II Technical Design Report|eprint=1011.0352|class=physics.ins-det}}</ref> to cope with the higher instantaneous luminosity provided by the SuperKEKB accelerator.<ref name=":0" /> Close to the beam pipe, the two innermost layers of Belle's silicon vertex detector have been replaced by a depleted [[Field-effect transistor|field effect transistor]] (DEPFET) pixel detector, and a larger silicon vertex detector.<ref name=":1" /><ref>{{Cite conference |last=Casarosa |first=Giulia |year=2015 |chapter=Inner tracking devices at the Belle II experiment |chapter-url=https://inspirehep.net/record/1430598 |title=Proceedings, 2015 European Physical Society Conference on High Energy Physics (EPS-HEP 2015) : Vienna, Austria, July 22-29, 2015 |page=255}}</ref> A larger central tracking system, a [[Wire chamber|wire drift chamber]], has been installed.<ref name=":1" /> Two new particle identification systems have been installed in the forward endcap (consisting of an [[aerogel]] [[ring-imaging Cherenkov detector]])<ref name=":1" /><ref>{{Cite journal |last=Nishida |first=S. |display-authors=etal |year=2014 |title=Aerogel RICH for the Belle II forward PID |journal=[[Nuclear Instruments and Methods in Physics Research Section A]] |volume=766 |pages=28–31 |bibcode=2014NIMPA.766...28N |doi=10.1016/j.nima.2014.06.061}}</ref> and in the barrel (consisting of quartz bars utilising [[Total internal reflection|totally internally reflected]] [[Cherenkov radiation|Cherenkov]] photons and measuring the time of propagation).<ref name=":1" /><ref>{{Cite journal |last=Inami |first=Kenji |year=2014 |title=TOP counter for particle identification at the Belle II experiment |journal=[[Nuclear Instruments and Methods in Physics Research Section A]] |volume=766 |pages=5–8 |bibcode=2014NIMPA.766....5I |doi=10.1016/j.nima.2014.07.006}}</ref> The original [[Caesium iodide|CsI]]([[Thallium|Tl]]) electromagnetic [[Calorimeter (particle physics)|calorimeter]] has been re-used (a new pure CsI calorimeter is being designed for the forward endcap<ref name=":2">{{Cite journal |last=Manoni |first=E. |display-authors=etal |year=2017 |title=The upgrade of the Belle II forward calorimeter |journal=[[Nuclear Instruments and Methods in Physics Research Section A]] |volume=845 |pages=524–527 |bibcode=2017NIMPA.845..524M |doi=10.1016/j.nima.2016.06.074}}</ref> to be installed at a later stage<ref name=":2" /><ref>{{Cite web |url=http://belle2.jp/electromagnetic-calorimeter/ |title=Electromagnetic Calorimeter {{!}} Belle{{nbsp}}II Experiment |website=belle2.jp |access-date=2017-05-07}}</ref>). The calorimeter readout electronics have been upgraded.<ref name=":1" /> Finally, scintillators have been installed in the endcaps and inner layers of Belle's {{Subatomic Particle|K-long0|link=yes}} and muon detector, the original [[Resistive plate chamber|resistive plate chambers]] from Belle are reused in the outer layers of the barrel.<ref name=":1" /><ref>{{Cite journal |last=Aushev |first=T. |display-authors=etal |year=2015 |title=A scintillator based endcap K<sub>L</sub> and muon detector for the Belle II experiment |journal=[[Nuclear Instruments and Methods in Physics Research Section A]] |volume=789 |pages=134–142 |bibcode=2015NIMPA.789..134A |doi=10.1016/j.nima.2015.03.060|arxiv = 1406.3267 |s2cid=118613296 }}</ref>


The target dataset is 50{{nbsp}}[[Barn (unit)|ab]]<sup>−1</sup> at Belle{{nbsp}}II<ref name=":1" /> compared to 988{{nbsp}}[[Barn (unit)|fb]]<sup>−1</sup> (with 711{{nbsp}}fb<sup>−1</sup> at the [[B-factory|Υ(4S) energy]]) at Belle.<ref>{{Cite journal|last1=Bevan|first1=A. J.|last2=Golob|first2=B.|last3=Mannel|first3=Th|last4=Prell|first4=S.|last5=Yabsley|first5=B. D.|last6=Aihara|first6=H.|last7=Anulli|first7=F.|last8=Arnaud|first8=N.|last9=Aushev|first9=T.|date=2014-11-01|title=The Physics of the B Factories|journal=The European Physical Journal C|language=en|volume=74|issue=11|pages=3026|doi=10.1140/epjc/s10052-014-3026-9|issn=1434-6044|arxiv = 1406.6311 |bibcode = 2014EPJC...74.3026B |s2cid=9063079}}</ref>
The target dataset is 50{{nbsp}}[[Barn (unit)|ab]]<sup>−1</sup> at Belle{{nbsp}}II<ref name=":1" /> compared to 988{{nbsp}}[[Barn (unit)|fb]]<sup>−1</sup> (with 711{{nbsp}}fb<sup>−1</sup> at the [[B-factory|Υ(4S) energy]]) at Belle.<ref>{{Cite journal|last1=Bevan|first1=A. J.|last2=Golob|first2=B.|last3=Mannel|first3=Th|last4=Prell|first4=S.|last5=Yabsley|first5=B. D.|last6=Aihara|first6=H.|last7=Anulli|first7=F.|last8=Arnaud|first8=N.|last9=Aushev|first9=T.|date=2014-11-01|title=The Physics of the B Factories|journal=The European Physical Journal C|language=en|volume=74|issue=11|pages=3026|doi=10.1140/epjc/s10052-014-3026-9|issn=1434-6044|arxiv = 1406.6311 |bibcode = 2014EPJC...74.3026B |s2cid=9063079}}</ref>

Revision as of 11:30, 25 October 2021

36°9′28″N 140°4′30″E / 36.15778°N 140.07500°E / 36.15778; 140.07500

The opened Belle II detector before installation of the inner tracking detectors.

The Belle II experiment is a particle physics experiment designed to study the properties of B mesons (heavy particles containing a bottom quark). Belle II is the successor to the Belle experiment, and commissioned at the SuperKEKB[1] accelerator complex at KEK in Tsukuba, Ibaraki prefecture, Japan. The Belle II detector was "rolled in" (moved into the collision point of SuperKEKB) on April 2017.[2][3] Belle II started taking data in early 2018.[1] Over its running period, Belle II is expected to collect around 50 times more data than its predecessor mostly due to a 40-fold increase in an instantaneous luminosity provided by SuperKEKB as compared to the previous KEKB accelerator.[1]

Detector upgrade

Much of the original Belle detector has been upgraded[4] to cope with the higher instantaneous luminosity provided by the SuperKEKB accelerator.[1] Close to the beam pipe, the two innermost layers of Belle's silicon vertex detector have been replaced by a depleted field effect transistor (DEPFET) pixel detector, and a larger silicon vertex detector.[4][5] A larger central tracking system, a wire drift chamber, has been installed.[4] Two new particle identification systems have been installed in the forward endcap (consisting of an aerogel ring-imaging Cherenkov detector)[4][6] and in the barrel (consisting of quartz bars utilising totally internally reflected Cherenkov photons and measuring the time of propagation).[4][7] The original CsI(Tl) electromagnetic calorimeter has been re-used (a new pure CsI calorimeter is being designed for the forward endcap[8] to be installed at a later stage[8][9]). The calorimeter readout electronics have been upgraded.[4] Finally, scintillators have been installed in the endcaps and inner layers of Belle's
K0
L and muon detector, the original resistive plate chambers from Belle are reused in the outer layers of the barrel.[4][10]

The target dataset is 50 ab−1 at Belle II[4] compared to 988 fb−1 (with 711 fb−1 at the Υ(4S) energy) at Belle.[11]

Construction work on the Central Drift Chamber (CDC) of the Belle II experiment.

Timeline

The Belle II data taking is separated into three phases:[12]

  • Phase I — completed Feb–June 2016: SuperKEKB commissioning to characterize the beam environment
  • Phase II — started early 2018, running without the inner silicon-based VXD tracking system to characterize background radiation in the innermost tracking system
  • Phase III — started 2019: data taking with the complete Belle II detector

On November 22 2018 the Belle II detector was completed with the installation of the VerteX Detector (VXD).[13] On March 25th 2019 the first collisions of the actual physics program were detected.[14]

See also

References

  1. ^ a b c d "SuperKEKB". www-superkekb.kek.jp. Retrieved 2017-04-28.
  2. ^ "Belle II Experiment on Twitter". Twitter. Retrieved 2017-05-07.
  3. ^ "Belle II rolls in - CERN Courier". cerncourier.com. Retrieved 2017-05-22.
  4. ^ a b c d e f g h Abe, T.; et al. (October 2010). "Belle II Technical Design Report". arXiv:1011.0352 [physics.ins-det].
  5. ^ Casarosa, Giulia (2015). "Inner tracking devices at the Belle II experiment". Proceedings, 2015 European Physical Society Conference on High Energy Physics (EPS-HEP 2015) : Vienna, Austria, July 22-29, 2015. p. 255.
  6. ^ Nishida, S.; et al. (2014). "Aerogel RICH for the Belle II forward PID". Nuclear Instruments and Methods in Physics Research Section A. 766: 28–31. Bibcode:2014NIMPA.766...28N. doi:10.1016/j.nima.2014.06.061.
  7. ^ Inami, Kenji (2014). "TOP counter for particle identification at the Belle II experiment". Nuclear Instruments and Methods in Physics Research Section A. 766: 5–8. Bibcode:2014NIMPA.766....5I. doi:10.1016/j.nima.2014.07.006.
  8. ^ a b Manoni, E.; et al. (2017). "The upgrade of the Belle II forward calorimeter". Nuclear Instruments and Methods in Physics Research Section A. 845: 524–527. Bibcode:2017NIMPA.845..524M. doi:10.1016/j.nima.2016.06.074.
  9. ^ "Electromagnetic Calorimeter | Belle II Experiment". belle2.jp. Retrieved 2017-05-07.
  10. ^ Aushev, T.; et al. (2015). "A scintillator based endcap KL and muon detector for the Belle II experiment". Nuclear Instruments and Methods in Physics Research Section A. 789: 134–142. arXiv:1406.3267. Bibcode:2015NIMPA.789..134A. doi:10.1016/j.nima.2015.03.060. S2CID 118613296.
  11. ^ Bevan, A. J.; Golob, B.; Mannel, Th; Prell, S.; Yabsley, B. D.; Aihara, H.; Anulli, F.; Arnaud, N.; Aushev, T. (2014-11-01). "The Physics of the B Factories". The European Physical Journal C. 74 (11): 3026. arXiv:1406.6311. Bibcode:2014EPJC...74.3026B. doi:10.1140/epjc/s10052-014-3026-9. ISSN 1434-6044. S2CID 9063079.
  12. ^ N.Braun - Hadron Spectroscopy Studies at Belle II
  13. ^ @belle2collab (November 22, 2018). "VerteX Detector (VXD) successfully installed in #Belle2. The Belle II detector is now complete!" (Tweet) – via Twitter.
  14. ^ Kick-off of the Belle II Phase 3 Physics Run

External links

Wikimedia Commons has media related to Belle II experiment.
Retrieved from "https://en.wikipedia.org/w/index.php?title=Belle_II_experiment&oldid=1051749610"