# Super-Kamiokande

> Cherenkov detector in Kamioka, Japan

**Wikidata**: [Q647227](https://www.wikidata.org/wiki/Q647227)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Super-Kamiokande)  
**Source**: https://4ort.xyz/entity/super-kamiokande

## Summary
Super-Kamiokande is a large-scale Cherenkov detector located in Kamioka, Japan, designed to detect neutrinos and study fundamental physics phenomena such as neutrino oscillations and supernova explosions. Operational since 1996, it succeeded the earlier Kamiokande experiment and has played a pivotal role in advancing neutrino research. It is part of the Kamioka Observatory and contributes to international experiments like T2K.

## Key Facts
- **Inception**: Construction began in December 1991, with operations starting on April 1, 1996.
- **Location**: Situated in Hida, Japan, at coordinates 36.4167° N, 137.3° E.
- **Type**: Cherenkov detector, neutrino detector, and research institute.
- **Affiliation**: Part of the Kamioka Observatory, K2K experiment, T2K experiment, and the SuperNova Early Warning System.
- **Awards**: Received the Asahi Prize in 1998.
- **Succession**: Followed by the Hyper-Kamiokande project.
- **Detection Capacity**: Uses 50,000 tons of ultra-pure water to detect neutrinos via Cherenkov radiation.

## FAQs
### Q: What is the primary purpose of Super-Kamiokande?
A: Super-Kamiokande detects neutrinos to study phenomena such as neutrino oscillations, supernovae, and proton decay, contributing to understanding the universe's fundamental physics.

### Q: Where is Super-Kamiokande located?
A: It is situated in the Kamioka Mine in Hida, Japan, approximately 1,000 meters underground to shield from cosmic radiation.

### Q: What major discovery is Super-Kamiokande known for?
A: It confirmed neutrino oscillations, proving neutrinos have mass—a breakthrough recognized with the 2015 Nobel Prize in Physics (awarded to Takaaki Kajita, among others).

## Why It Matters
Super-Kamiokande is a cornerstone of modern neutrino physics, enabling groundbreaking discoveries such as the confirmation of neutrino oscillations, which demonstrated that neutrinos possess mass. This finding resolved a long-standing puzzle in particle physics and reshaped the Standard Model. The detector’s immense scale and sensitivity allow it to capture rare neutrino events, including those from supernovae, providing critical insights into stellar evolution and the universe’s structure. By participating in experiments like T2K and monitoring supernova neutrinos, Super-Kamiokande contributes to both fundamental science and practical applications, such as early warnings for impending supernovae. Its legacy extends to next-generation projects like Hyper-Kamiokande, ensuring continued advancement in neutrino research.

## Notable For
- **Scale and Sensitivity**: One of the largest neutrino detectors globally, utilizing 50,000 tons of purified water to detect Cherenkov radiation from neutrino interactions.
- **Neutrino Oscillation Discovery**: Played a central role in confirming neutrino oscillations, leading to the 2015 Nobel Prize in Physics for collaborator Takaaki Kajita.
- **Supernova Monitoring**: Part of the SuperNova Early Warning System, designed to detect neutrino bursts from impending supernovae in the Milky Way.
- **International Collaboration**: Integral to experiments like T2K (Tokai-to-Kamioka), studying neutrino properties through long-baseline oscillation studies.
- **Awards and Recognition**: Received the prestigious Asahi Prize in 1998 for its scientific contributions.

## Body

### History and Development
- **Predecessor**: Built upon the success of the Kamiokande experiment, which operated from 1983 to 1995.
- **Construction**: Began in December 1991, with initial operations starting in April 1996.
- **Upgrades**: Underwent significant upgrades, including the addition of gadolinium to enhance neutron detection capabilities (Super-Kamiokande-Gd phase).

### Technical Specifications
- **Detector Design**: Cylindrical structure, 39.3 meters in diameter and 41.4 meters tall, containing 50,000 tons of ultra-pure water.
- **Photodetectors**: Equipped with over 13,000 photomultiplier tubes (PMTs) to detect Cherenkov light from particle interactions.
- **Location**: Situated 1,000 meters underground in the Mozumi Mine to minimize background noise from cosmic rays.

### Research Contributions
- **Neutrino Oscillations**: Provided definitive evidence of neutrino flavor changes, confirming neutrinos have mass.
- **Proton Decay Studies**: Continues to search for proton decay, a predicted phenomenon in grand unified theories (GUTs).
- **Astrophysical Neutrinos**: Monitors neutrinos from solar, atmospheric, and supernova sources, offering insights into stellar processes.

### Collaborations and Legacy
- **Experiments**: Core component of the T2K (Tokai-to-Kamioka) and K2K experiments, studying neutrino oscillations over long baselines.
- **Successor**: Paves the way for Hyper-Kamiokande, a next-generation detector with enhanced sensitivity and scale.
- **Global Impact**: Data from Super-Kamiokande has influenced fields beyond particle physics, including astrophysics and cosmology.

## References

1. [Source](https://www.asahi.com/corporate/award/asahi/12738070)
2. [研究史](https://www-sk.icrr.u-tokyo.ac.jp/sk/about/history/)
3. Freebase Data Dumps. 2013
4. [OpenAlex](https://docs.openalex.org/download-snapshot/snapshot-data-format)