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159-517: 36°25′32.6″N 137°18′37.1″E  /  36.425722°N 137.310306°E  / 36.425722; 137.310306 Super-Kamiokande (abbreviation of Super-Kamioka Neutrino Detection Experiment , also abbreviated to Super-K or SK ; Japanese : スーパーカミオカンデ ) is a neutrino observatory located under Mount Ikeno near the city of Hida , Gifu Prefecture , Japan. It is operated by the Institute for Cosmic Ray Research , University of Tokyo with

318-408: A "track" of Cherenkov photons. The data from this track can be used to reconstruct the directionality of the muon. For high-energy interactions, the neutrino and muon directions are the same, so it's possible to tell where the neutrino came from. This is pointing direction is important in extra-solar system neutrino astronomy. Along with time, position, and possibly direction, it's possible to infer

477-558: A 2.22MeV gamma-ray as the nucleus de-excites. This process on average takes on the order of 256 microseconds. By searching for time and spatial coincidence of these gamma rays, the experimenters can be certain there was an event. Using over 3,200 days of data, Borexino used geoneutrinos to place constraints on the composition and power output of the mantle. They found that the ratio of U 238 {\displaystyle {\ce {^{238}U}}} to Th 232 {\displaystyle {\ce {^{232}Th}}}

636-426: A Chlorine isotope and can create radioactive Argon. Gallium to Germanium conversion has also been used. The IceCube Neutrino Observatory built in 2010 in the south pole is the biggest neutrino detector, consisting of thousands of optical sensors buried 500 meters underneath a cubic kilometer of deep, ultra-transparent ice, detects light emitted by charged particles that are produced when a single neutrino collides with

795-637: A benefit from the in-group to the out-group) means "[I/we] explained [it] to [him/her/them]". Such beneficiary auxiliary verbs thus serve a function comparable to that of pronouns and prepositions in Indo-European languages to indicate the actor and the recipient of an action. Japanese "pronouns" also function differently from most modern Indo-European pronouns (and more like nouns) in that they can take modifiers as any other noun may. For instance, one does not say in English: The amazed he ran down

954-594: A complex system of honorifics , with verb forms and vocabulary to indicate the relative status of the speaker, the listener, and persons mentioned. The Japanese writing system combines Chinese characters , known as kanji ( 漢字 , ' Han characters') , with two unique syllabaries (or moraic scripts) derived by the Japanese from the more complex Chinese characters: hiragana ( ひらがな or 平仮名 , 'simple characters') and katakana ( カタカナ or 片仮名 , 'partial characters'). Latin script ( rōmaji ローマ字 )

1113-405: A cylindrical stainless steel tank that is 41.4 m (136 ft) tall and 39.3 m (129 ft) in diameter holding 50,220 tonnes (55,360 US tons) of ultrapure water . The tank volume is divided by a stainless steel superstructure into an inner detector (ID) region, which is 36.2 m (119 ft) in height and 33.8 m (111 ft) in diameter, and outer detector (OD) which consists of

1272-459: A depth of 2 km. The second phase as well as plans to deploy the full-size prototype tower will be pursued in the KM3NeT framework. The NESTOR Project was installed in 2004 to a depth of 4 km and operated for one month until a failure of the cable to shore forced it to be terminated. The data taken still successfully demonstrated the detector's functionality and provided a measurement of

1431-524: A depth of about 2000 m that was sufficient for track reconstruction. The AMANDA array was subsequently upgraded until January 2000 when it consisted of 19 strings with a total of 667 optical modules at a depth range between 1500 m and 2000 m. AMANDA would eventually be the predecessor to IceCube in 2005. An example of an early neutrino detector is the Artyomovsk Scintillation Detector  [ ru ] (ASD), located in

1590-414: A distinct language of its own that has absorbed various aspects from neighboring languages. Japanese has five vowels, and vowel length is phonemic, with each having both a short and a long version. Elongated vowels are usually denoted with a line over the vowel (a macron ) in rōmaji , a repeated vowel character in hiragana , or a chōonpu succeeding the vowel in katakana . /u/ ( listen )

1749-419: A glide /j/ and either the first part of a geminate consonant ( っ / ッ , represented as Q) or a moraic nasal in the coda ( ん / ン , represented as N). The nasal is sensitive to its phonetic environment and assimilates to the following phoneme, with pronunciations including [ɴ, m, n, ɲ, ŋ, ɰ̃] . Onset-glide clusters only occur at the start of syllables but clusters across syllables are allowed as long as

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1908-484: A listener depending on the listener's relative social position and the degree of familiarity between the speaker and the listener. When used in different social relationships, the same word may have positive (intimate or respectful) or negative (distant or disrespectful) connotations. Japanese often use titles of the person referred to where pronouns would be used in English. For example, when speaking to one's teacher, it

2067-521: A long time to diffuse outward. Therefore, neutrinos are the only way that we can obtain real-time data about the nuclear processes in the Sun. There are two main processes for stellar nuclear fusion. The first is the Proton-Proton (PP) chain, in which protons are fused together into helium, sometimes temporarily creating the heavier elements of lithium, beryllium, and boron along the way. The second

2226-412: A longer half-life, with rarer decays. To increase the chance of detecting such decays, a larger detector was needed. A higher sensitivity was also necessary to obtain a higher statistical confidence in other detections. This led to the design and construction of Super-Kamiokande, with fifteen times the volume of water and ten times as many PMTs as Kamiokande. The Super-Kamiokande project was approved by

2385-501: A maximum depth of 2475 m. NEMO (NEutrino Mediterranean Observatory) was pursued by Italian groups to investigate the feasibility of a cubic-kilometer scale deep-sea detector. A suitable site at a depth of 3.5 km about 100 km off Capo Passero at the South-Eastern coast of Sicily has been identified. From 2007 to 2011 the first prototyping phase tested a "mini-tower" with 4 bars deployed for several weeks near Catania at

2544-648: A nearby nuclear reactor as a neutrino source. Their discovery was acknowledged with a Nobel Prize for physics in 1995. This was followed by the first atmospheric neutrino detection in 1965 by two groups almost simultaneously. One was led by Frederick Reines who operated a liquid scintillator - the Case-Witwatersrand-Irvine or CWI detector - in the East Rand gold mine in South Africa at an 8.8 km water depth equivalent. The other

2703-470: A newly developed custom charge-to-time converter (QTC) in the form of an application-specific integrated circuit (ASIC), a multi-hit time-to-digital converter (TDC), and field-programmable gate array (FPGA). Each QTC input has three gain ranges "Small", "Medium" and "Large" – the resolutions for each are shown in Table. For each range, analog to digital conversion is conducted separately, but the only range used

2862-551: A positron. Gadolinium has an affinity for neutrons and produces a bright flash of gamma rays when it absorbs one. Adding gadolinium to the Super-Kamiokande allows it to distinguish between neutrinos and antineutrinos. Antineutrinos produce a double flash of light about 30 microseconds apart, first when the neutrino hits a proton and second when gadolinium absorbs a neutron. The brightness of the first flash allows physicists to distinguish between low energy antineutrinos from

3021-514: A precursor to many of the following telescopes in the following decades. The Baikal Neutrino Telescope is installed in the southern part of Lake Baikal in Russia. The detector is located at a depth of 1.1 km and began surveys in 1980. In 1993, it was the first to deploy three strings to reconstruct the muon trajectories as well as the first to record atmospheric neutrinos underwater. AMANDA (Antarctic Muon And Neutrino Detector Array) used

3180-600: A primary decision for further process. If the burst candidate passes these checks, the data will be reanalyzed using an offline process and a final decision will be made within a few hours. During the Super-Kamiokande I running, this never occurred. One of the important capabilities for [Super-Kamiokande] is to reconstruct the direction to supernova. By neutrino–electron scattering, ν x + e − → ν x + e − {\displaystyle \nu _{\text{x}}+e^{-}\to \nu _{\text{x}}+e^{-}} ,

3339-661: A proton or neutron inside an atom. The resulting nuclear reaction produces secondary particles traveling at high speeds that give off a blue light called Cherenkov radiation . Super-Kamiokande in Japan and ANTARES and KM3NeT in the Mediterranean are some other important neutrino detectors. Since neutrinos interact weakly, neutrino detectors must have large target masses (often thousands of tons). The detectors also must use shielding and effective software to remove background signal. Since neutrinos are very difficult to detect,

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3498-622: A result of certain types of radioactive decay , nuclear reactions such as those that take place in the Sun or high energy astrophysical phenomena, in nuclear reactors , or when cosmic rays hit atoms in the atmosphere. Neutrinos rarely interact with matter (only via the weak nuclear force), travel at nearly the speed of light in straight lines, pass through large amounts of matter without any notable absorption or without being deflected by magnetic fields. Unlike photons, neutrinos rarely scatter along their trajectory. But like photons, neutrinos are some of

3657-424: A rock support system and radon gas barrier in the mining industry. The average geomagnetic field is about 450 mG and is inclined by about 45° with respect to the horizon at the detector site. This presents a problem for the large and very sensitive PMTs which prefer a much lower ambient field. The strength and uniform direction of the geomagnetic field could systematically bias photoelectron trajectories and timing in

3816-408: A sentence need not be stated and pronouns may be omitted if they can be inferred from context. In the example above, hana ga nagai would mean "[their] noses are long", while nagai by itself would mean "[they] are long." A single verb can be a complete sentence: Yatta! ( やった! ) "[I / we / they / etc] did [it]!". In addition, since adjectives can form the predicate in a Japanese sentence (below),

3975-428: A single adjective can be a complete sentence: Urayamashii! ( 羨ましい! ) "[I'm] jealous [about it]!". While the language has some words that are typically translated as pronouns, these are not used as frequently as pronouns in some Indo-European languages, and function differently. In some cases, Japanese relies on special verb forms and auxiliary verbs to indicate the direction of benefit of an action: "down" to indicate

4134-544: A supernova at the center of the Milky Way Galaxy. In this case, not only time profile and the energy spectrum of a neutrino burst, but also the information on direction of supernova can be provided. There is a process called the "slow control" monitor, as part of the online monitoring system, watches the status of the HV systems, the temperatures of electronics crates and the status of the compensating coils used to cancel

4293-551: A supernova explosion at the center of the Milky Way Galaxy. Super-Kamiokande can measure a burst with no dead-time, up to 30,000 events within the first second of a burst. Theoretical calculations of supernova explosions suggest that neutrinos are emitted over a total time-scale of tens of seconds with about a half of them emitted during the first one or two seconds. The Super-K will search for event clusters in specified time windows of 0.5, 2 and 10 s. Data are transmitted to realtime SN-watch analysis process every 2 min and analysis

4452-517: A surface drawn 2.00 m from the ID wall to minimize the anomalous response caused by natural radioactivity in the surrounding rock. An online monitor computer located in the control room reads data from the DAQ host computer via an FDDI link. It provides shift operators with a flexible tool for selecting event display features, makes online and recent-history histograms to monitor detector performance, and performs

4611-475: A total of 100–150 events are expected in case of a supernova at the center of the Milky Way Galaxy. The direction to supernova can be measured with angular resolution δ θ ∼ 30 ∘ N {\displaystyle \delta \theta \sim {30^{\circ } \over {\sqrt {N}}}} where N is the number of events produced by the ν–e scattering. The angular resolution, therefore, can be as good as δθ~3° for

4770-497: A variety of additional tasks needed to efficiently monitor status and diagnose detector and DAQ problems. Events in the data stream can be skimmed off and elementary analysis tools can be applied to check data quality during calibrations or after changes in hardware or online software. To detect and identify such bursts as efficiently and promptly as possible Super-Kamiokande is equipped with an online supernova monitor system. About 10,000 total events are expected in Super-Kamiokande for

4929-559: A wide dynamic range. The integrated charge linearity of the electronics is better than 1%. The thresholds of the discriminators in the QTC are set to −0.69 mV (equivalent to 0.25 photoelectron, which is the same as for SK-III). This threshold was chosen to replicate the behavior of the detector during its previous ATM-based phases. Gadolinium was introduced into the Super-Kamiokande water tank in 2020 in order to distinguish neutrinos from antineutrinos that arise from supernova explosions. This

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5088-624: Is compressed rather than protruded , or simply unrounded. Some Japanese consonants have several allophones , which may give the impression of a larger inventory of sounds. However, some of these allophones have since become phonemic. For example, in the Japanese language up to and including the first half of the 20th century, the phonemic sequence /ti/ was palatalized and realized phonetically as [tɕi] , approximately chi ( listen ) ; however, now [ti] and [tɕi] are distinct, as evidenced by words like tī [tiː] "Western-style tea" and chii [tɕii] "social status". The "r" of

5247-448: Is also seen in o-medetō "congratulations", from medetaku ). Late Middle Japanese has the first loanwords from European languages – now-common words borrowed into Japanese in this period include pan ("bread") and tabako ("tobacco", now "cigarette"), both from Portuguese . Modern Japanese is considered to begin with the Edo period (which spanned from 1603 to 1867). Since Old Japanese,

5406-527: Is also used in a limited fashion (such as for imported acronyms) in Japanese writing. The numeral system uses mostly Arabic numerals , but also traditional Chinese numerals . Proto-Japonic , the common ancestor of the Japanese and Ryukyuan languages , is thought to have been brought to Japan by settlers coming from the Korean peninsula sometime in the early- to mid-4th century BC (the Yayoi period ), replacing

5565-643: Is an agglutinative , mora -timed language with relatively simple phonotactics , a pure vowel system, phonemic vowel and consonant length, and a lexically significant pitch-accent . Word order is normally subject–object–verb with particles marking the grammatical function of words, and sentence structure is topic–comment . Sentence-final particles are used to add emotional or emphatic impact, or form questions. Nouns have no grammatical number or gender , and there are no articles . Verbs are conjugated , primarily for tense and voice , but not person . Japanese adjectives are also conjugated. Japanese has

5724-440: Is appropriate to use sensei ( 先生 , "teacher"), but inappropriate to use anata . This is because anata is used to refer to people of equal or lower status, and one's teacher has higher status. Japanese nouns have no grammatical number, gender or article aspect. The noun hon ( 本 ) may refer to a single book or several books; hito ( 人 ) can mean "person" or "people", and ki ( 木 ) can be "tree" or "trees". Where number

5883-701: Is associated with comedy (see Kansai dialect ). Dialects of Tōhoku and North Kantō are associated with typical farmers. The Ryūkyūan languages, spoken in Okinawa and the Amami Islands (administratively part of Kagoshima ), are distinct enough to be considered a separate branch of the Japonic family; not only is each language unintelligible to Japanese speakers, but most are unintelligible to those who speak other Ryūkyūan languages. However, in contrast to linguists, many ordinary Japanese people tend to consider

6042-466: Is better documentation of Late Middle Japanese phonology than for previous forms (for instance, the Arte da Lingoa de Iapam ). Among other sound changes, the sequence /au/ merges to /ɔː/ , in contrast with /oː/ ; /p/ is reintroduced from Chinese; and /we/ merges with /je/ . Some forms rather more familiar to Modern Japanese speakers begin to appear – the continuative ending - te begins to reduce onto

6201-1018: Is completed typically in 1 min. When supernova (SN) event candidates are found, R mean {\displaystyle {R_{\text{mean}}}} is calculated if the event multiplicity is larger than 16, where R mean {\displaystyle {R_{\text{mean}}}} is defined as the average spatial distance between events, i.e. R mean = ∑ i = 1 N multi − 1 ∑ j = i + 1 N multi | r i − r j | N multi C 2 {\displaystyle {R_{\text{mean}}}={\frac {\sum _{i=1}^{{N_{\text{multi}}}-1}\sum _{j=i+1}^{N_{\text{multi}}}|{r_{\text{i}}}-{r_{\text{j}}}|}{{N_{\text{multi}}}{C_{\text{2}}}}}} Neutrinos from supernovae interact with free protons, producing positrons which are distributed so uniformly in

6360-509: Is correlated with the sex of the speaker and the social situation in which they are spoken: men and women alike in a formal situation generally refer to themselves as watashi ( 私 , literally "private") or watakushi (also 私 , hyper-polite form), while men in rougher or intimate conversation are much more likely to use the word ore ( 俺 "oneself", "myself") or boku . Similarly, different words such as anata , kimi , and omae ( お前 , more formally 御前 "the one before me") may refer to

6519-417: Is important, it can be indicated by providing a quantity (often with a counter word ) or (rarely) by adding a suffix, or sometimes by duplication (e.g. 人人 , hitobito , usually written with an iteration mark as 人々 ). Words for people are usually understood as singular. Thus Tanaka-san usually means Mx Tanaka . Words that refer to people and animals can be made to indicate a group of individuals through

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6678-504: Is known as the SK-Gd project (other names include SuperKGd , SUPERK-GD , and similar names). In the first phase of the project, 1.3 tons of a Gd salt (gadolinium sulfate octahydrate, Gd(SO 4 ) 3 ⋅(H 2 O) 8 ) were added to the ultrapure water in 2020, giving 0.02% (by mass) of the salt. This amount is about a tenth of the planned final target concentration. Nuclear fusion in the Sun and other stars turns protons into neutrons with

6837-504: Is known of the language's prehistory, or when it first appeared in Japan. Chinese documents from the 3rd century AD recorded a few Japanese words, but substantial Old Japanese texts did not appear until the 8th century. From the Heian period (794–1185), extensive waves of Sino-Japanese vocabulary entered the language, affecting the phonology of Early Middle Japanese . Late Middle Japanese (1185–1600) saw extensive grammatical changes and

6996-755: Is less common. In terms of mutual intelligibility , a survey in 1967 found that the four most unintelligible dialects (excluding Ryūkyūan languages and Tōhoku dialects ) to students from Greater Tokyo were the Kiso dialect (in the deep mountains of Nagano Prefecture ), the Himi dialect (in Toyama Prefecture ), the Kagoshima dialect and the Maniwa dialect (in Okayama Prefecture ). The survey

7155-420: Is often called a topic-prominent language , which means it has a strong tendency to indicate the topic separately from the subject, and that the two do not always coincide. The sentence Zō wa hana ga nagai ( 象は鼻が長い ) literally means, "As for elephant(s), (the) nose(s) (is/are) long". The topic is zō "elephant", and the subject is hana "nose". Japanese grammar tends toward brevity; the subject or object of

7314-402: Is possible to trace back the direction of the incoming neutrino. These high-energy neutrinos are either the primary or secondary cosmic rays produced by energetic astrophysical processes. Observing neutrinos could provide insights into these processes beyond what is observable with electromagnetic radiation. In the case of the neutrino detected from a distant blazar, multi-wavelength astronomy

7473-498: Is preserved in words such as matsuge ("eyelash", lit. "hair of the eye"); modern mieru ("to be visible") and kikoeru ("to be audible") retain a mediopassive suffix - yu(ru) ( kikoyu → kikoyuru (the attributive form, which slowly replaced the plain form starting in the late Heian period) → kikoeru (all verbs with the shimo-nidan conjugation pattern underwent this same shift in Early Modern Japanese )); and

7632-692: Is provided where θ S u n {\displaystyle \theta _{Sun}} is the angle between the direction of recoil electrons and the Sun's position. This shows that the 8 B {\displaystyle {}^{8}\!B} solar neutrino flux can be calculated to be 2.40 ± 0.03 ( s t a t . ) − 0.07 + 0.08 ( s y s . ) × 10 6 c m − 2 s − 1 {\displaystyle 2.40\pm 0.03(stat.){}_{-0.07}^{+0.08}\!(sys.)\times 10^{6}cm^{-2}s^{-1}} . Comparing to

7791-413: Is sent to professional and amateur astronomers to be on the lookout for supernova light. By using the distance between detectors and the time difference between detections, the alert can also include directionality as to the supernova's location in the sky. The Sun, like other stars, is powered by nuclear fusion in its core. The core is incredibly large, meaning that photons produced in the core will take

7950-448: Is that anti-electron neutrinos can interact with a nucleus in the detector by inverse beta decay and produce a positron and a neutron. The positron immediately will annihilate with an electron, producing two 511keV photons. The neutron will attach to another nucleus and give off a gamma with an energy of a few MeV. In general, neutrinos can interact through neutral-current and charged-current interactions. In neutral-current interactions,

8109-514: Is that with the highest resolution that is not being saturated. The overall charge dynamic range of the QTC is 0.2–2500 pC, five times larger than the old . The charge and timing resolution of the QBEE at the single photoelectron level is 0.1 photoelectrons and 0.3 ns respectively, both are better than the intrinsic resolution of the 20-in. PMTs used in SK. The QBEE achieves good charge linearity over

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8268-487: Is the CNO cycle, in which carbon, nitrogen, and oxygen are fused with protons, and then undergo alpha decay (helium nucleus emission) to begin the cycle again. The PP chain is the primary process in the Sun, while the CNO cycle is more dominant in stars more massive than the Sun. Each step in the process has an allowed spectra of energy for the neutrino (or a discrete energy for electron capture processes). The relative rates of

8427-473: Is the same as chondritic meteorites. The power output from uranium and thorium in Earth's mantle was found to be 14.2-35.7 TW with a 68% confidence interval. Neutrino tomography also provides insight into the interior of Earth. For neutrinos with energies of a few TeV, the interaction probability becomes non-negligible when passing through Earth. The interaction probability will depend on the number of nucleons

8586-402: Is the version of Japanese discussed in this article. Formerly, standard Japanese in writing ( 文語 , bungo , "literary language") was different from colloquial language ( 口語 , kōgo ) . The two systems have different rules of grammar and some variance in vocabulary. Bungo was the main method of writing Japanese until about 1900; since then kōgo gradually extended its influence and

8745-471: Is used for the present and the future. For verbs that represent an ongoing process, the -te iru form indicates a continuous (or progressive) aspect , similar to the suffix ing in English. For others that represent a change of state, the -te iru form indicates a perfect aspect. For example, kite iru means "They have come (and are still here)", but tabete iru means "They are eating". Questions (both with an interrogative pronoun and yes/no questions) have

8904-405: Is why some linguists do not classify Japanese "pronouns" as pronouns, but rather as referential nouns, much like Spanish usted (contracted from vuestra merced , "your ( majestic plural ) grace") or Portuguese você (from vossa mercê ). Japanese personal pronouns are generally used only in situations requiring special emphasis as to who is doing what to whom. The choice of words used as pronouns

9063-578: The Homestake experiment . Davis, along with Japanese physicist Masatoshi Koshiba were jointly awarded half of the 2002 Nobel Prize in Physics "for pioneering contributions to astrophysics, in particular for the detection of cosmic neutrinos (the other half went to Riccardo Giacconi for corresponding pioneering contributions which have led to the discovery of cosmic X-ray sources)." The first generation of undersea neutrino telescope projects began with

9222-608: The Institute for Cosmic Ray Research , University of Tokyo began in 1982 and was completed in April 1983. The purpose of the observatory was to detect whether proton decay exists, one of the most fundamental questions of elementary particle physics. The detector, named KamiokaNDE for Kamioka Nucleon Decay Experiment, was a tank 16.0 m (52 ft) in height and 15.6 m (51.2 ft) in width, containing 3,058 tonnes (3,400 US tons) of pure water and about 1,000 photomultiplier tubes (PMTs) attached to its inner surface. The detector

9381-517: The Japonic language family, which also includes the Ryukyuan languages spoken in the Ryukyu Islands . As these closely related languages are commonly treated as dialects of the same language, Japanese is sometimes called a language isolate . According to Martine Irma Robbeets , Japanese has been subject to more attempts to show its relation to other languages than any other language in

9540-514: The Philippines , and various Pacific islands, locals in those countries learned Japanese as the language of the empire. As a result, many elderly people in these countries can still speak Japanese. Japanese emigrant communities (the largest of which are to be found in Brazil , with 1.4 million to 1.5 million Japanese immigrants and descendants, according to Brazilian IBGE data, more than

9699-757: The Soledar Salt Mine in Ukraine at a depth of more than 100 m. It was created in the Department of High Energy Leptons and Neutrino Astrophysics of the Institute of Nuclear Research of the USSR Academy of Sciences in 1969 to study antineutrino fluxes from collapsing stars in the Galaxy, as well as the spectrum and interactions of muons of cosmic rays with energies up to 10 ^ 13 eV. A feature of

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9858-500: The Sun . These neutrinos primarily come through the p-p chain in lower masses, and for cooler stars, primarily through the CNO cycle of heavier masses. In the early 1990s, particularly with the uncertainties that accompanied the initial results from Kamioka II and the Ga experiments, no individual experiment required a non-astrophysical solution of the solar neutrino problem. But in aggregate,

10017-738: The United States (notably in Hawaii , where 16.7% of the population has Japanese ancestry, and California ), and the Philippines (particularly in Davao Region and the Province of Laguna ). Japanese has no official status in Japan, but is the de facto national language of the country. There is a form of the language considered standard : hyōjungo ( 標準語 ) , meaning "standard Japanese", or kyōtsūgo ( 共通語 ) , "common language", or even "Tokyo dialect" at times. The meanings of

10176-457: The blazar TXS 0506+056 located 3.7 billion light-years away in the direction of the constellation Orion . This is the first time that a neutrino detector has been used to locate an object in space and that a source of cosmic rays has been identified. In November 2022, the IceCube collaboration made another significant progress towards identifying the origin of cosmic rays, reporting

10335-406: The cosmic neutrino background , origins of ultra-high-energy neutrinos, neutrino properties (such as neutrino mass hierarchy), dark matter properties, etc. It will become an integral part of multi-messenger astronomy, complementing gravitational astronomy and traditional telescopic astronomy. Neutrinos were first recorded in 1956 by Clyde Cowan and Frederick Reines in an experiment employing

10494-806: The de facto standard Japanese had been the Kansai dialect , especially that of Kyoto . However, during the Edo period, Edo (now Tokyo) developed into the largest city in Japan, and the Edo-area dialect became standard Japanese. Since the end of Japan's self-imposed isolation in 1853, the flow of loanwords from European languages has increased significantly. The period since 1945 has seen many words borrowed from other languages—such as German, Portuguese and English. Many English loan words especially relate to technology—for example, pasokon (short for "personal computer"), intānetto ("internet"), and kamera ("camera"). Due to

10653-411: The solar neutrino problem . The Sun and about 80% of the visible stars produce their energy by the conversion of hydrogen to helium via 4 p → 4 H e + 2 e + + 2 ν e + 26.73 {\displaystyle 4p\to {}^{4}\!He+2e^{+}+2\nu _{e}+26.73} MeV Consequently, stars are a source of neutrinos, including

10812-458: The speed of light in water , which is slower than the speed of light in vacuum . This creates a cone of light known as Cherenkov radiation , which is the optical equivalent to a sonic boom . The Cherenkov light is projected as a ring on the wall of the detector and recorded by the PMTs. Using the timing and charge information recorded by each PMT, the interaction vertex, ring direction and flavor of

10971-635: The "alarm" class of burst, the events are required to have R mean {\displaystyle {R_{\text{mean}}}} ⩾900 cm for 25⩽ N multi {\displaystyle {N_{\text{multi}}}} ⩽40 or R mean {\displaystyle {R_{\text{mean}}}} ⩾750 cm for N multi {\displaystyle {N_{\text{multi}}}} >40. These thresholds were determined by extrapolation from SN1987A data. The system will run special processes to check for spallation muons when burst candidates meeting "alarm" criteria and make

11130-527: The 1.2 million of the United States ) sometimes employ Japanese as their primary language. Approximately 12% of Hawaii residents speak Japanese, with an estimated 12.6% of the population of Japanese ancestry in 2008. Japanese emigrants can also be found in Peru , Argentina , Australia (especially in the eastern states), Canada (especially in Vancouver , where 1.4% of the population has Japanese ancestry),

11289-568: The 3 km thick ice layer at the South Pole and was located several hundred meters from the Amundsen-Scott station . Holes 60 cm in diameter were drilled with pressurized hot water in which strings with optical modules were deployed before the water refroze. The depth proved to be insufficient to be able to reconstruct the trajectory due to the scattering of light on air bubbles. A second group of 4 strings were added in 1995/96 to

11448-590: The Abyss ). Both KM3NeT and GVD have completed at least part of their construction and it is expected that these two along with IceCube will form a global neutrino observatory. In July 2018, the IceCube Neutrino Observatory announced that they have traced an extremely-high-energy neutrino that hit their Antarctica-based research station in September 2017 back to its point of origin in

11607-576: The Antarctic ice. The KM3NeT in the Mediterranean Sea and the GVD are in their preparatory/prototyping phase. IceCube instruments 1 km of ice. GVD is also planned to cover 1 km but at a much higher energy threshold. KM3NeT is planned to cover several km and have two components; ARCA ( Astroparticle Research with Cosmics in the Abyss ) and ORCA ( Oscillations Research with Cosmics in

11766-783: The Cl, Kamioka II, and Ga experiments indicated a pattern of neutrino fluxes that was not compatible with any adjustment of the SSM. This in turn helped motivate a new generation of spectacularly capable active detectors. These experiments are Super-Kamiokande, the Sudbury Neutrino Observatory (SNO), and Borexino . Super-Kamiokande was able to detect elastic scattering (ES) events ν x + e − → ν x + e − {\displaystyle \nu _{x}+e^{-}\to \nu _{x}+e^{-}} which, due to

11925-475: The Earth and high energy antineutrinos from supernovas. In addition to observing neutrinos from distant supernovas, the Super-Kamiokande will be able to set off an alarm to inform astronomers around the world of the presence of a supernova in the Milky Way within one second of it occurring. The biggest challenge was whether the detector's water could be continuously filtered to remove impurities without removing

12084-474: The ID PMTs is a "supermodule", a frame which supports a 3×4 array of PMTs. Supermodule frames are 2.1 m in height, 2.8 m in width and 0.55 m in thickness. These frames are connected to each other in both the vertical and horizontal directions. Then the whole support structure is connected to the bottom of the tank and to the top structure. In addition to serving as rigid structural elements, supermodules simplified

12243-700: The Japanese Ministry of Education, Science, Sports and Culture in 1991 for total funding of approximately $ 100 million. The US portion of the proposal, which was primarily to build the OD system, was approved by the US Department of Energy in 1993 for $ 3M. In addition, the US has also contributed about 2000 20 cm PMTs recycled from the IMB experiment . Super-Kamiokande started operation in 1996 and announced

12402-486: The Japanese language is of particular interest, ranging between an apical central tap and a lateral approximant . The "g" is also notable; unless it starts a sentence, it may be pronounced [ ŋ ] , in the Kanto prestige dialect and in other eastern dialects. The phonotactics of Japanese are relatively simple. The syllable structure is (C)(G)V(C), that is, a core vowel surrounded by an optional onset consonant,

12561-419: The Milky Way galaxy . Neutrinos interact incredibly rarely with matter, so the vast majority of neutrinos will pass through a detector without interacting. If a neutrino does interact, it will only do so once. Therefore, to perform neutrino astronomy, large detectors must be used to obtain enough statistics. The method of neutrino detection depends on the energy and type of the neutrino. A famous example

12720-736: The Old Japanese sections are written in Man'yōgana , which uses kanji for their phonetic as well as semantic values. Based on the Man'yōgana system, Old Japanese can be reconstructed as having 88 distinct morae . Texts written with Man'yōgana use two different sets of kanji for each of the morae now pronounced き (ki), ひ (hi), み (mi), け (ke), へ (he), め (me), こ (ko), そ (so), と (to), の (no), も (mo), よ (yo) and ろ (ro). (The Kojiki has 88, but all later texts have 87. The distinction between mo 1 and mo 2 apparently

12879-412: The PMTs. To counteract this 26 sets of horizontal and vertical Helmholtz coils are arranged around the inner surfaces of the tank. With these in operation the average field in the detector is reduced to about 50 mG. The magnetic field at various PMT locations were measured before the tank was filled with water. A standard fiducial volume of approximately 22.5 kilotonnes is defined as the region inside

13038-488: The Ryūkyūan languages as dialects of Japanese. The imperial court also seems to have spoken an unusual variant of the Japanese of the time, most likely the spoken form of Classical Japanese , a writing style that was prevalent during the Heian period , but began to decline during the late Meiji period . The Ryūkyūan languages are classified by UNESCO as 'endangered', as young people mostly use Japanese and cannot understand

13197-488: The SSM, the ratio is D a t a S S M B P 98 = 0.465 ± 0.005 ( s t a t . ) − 0.013 + 0.015 ( s y s . ) {\displaystyle {Data \over SSM_{BP98}}=0.465\pm 0.005(stat.){}_{-0.013}^{+0.015}\!(sys.)} . The result clearly indicates the deficit of solar neutrinos. Atmospheric neutrinos are secondary cosmic rays produced by

13356-437: The Sun's nuclear processes can be determined by observations in its flux at different energies. This would shed insight into the Sun's properties, such as metallicity , which is the composition of heavier elements. Borexino is one of the detectors studying solar neutrinos. In 2018, they found 5σ significance for the existence of neutrinos from the fusing of two protons with an electron (pep neutrinos). In 2020, they found for

13515-541: The Supernova Early Warning System ( SNEWS ). In a core collapse supernova, ninety-nine percent of the energy released will be in neutrinos. While photons can be trapped in the dense supernova for hours, neutrinos are able to escape on the order of seconds. Since neutrinos travel at roughly the speed of light, they can reach Earth before photons do. If two or more of SNEWS detectors observe a coincidence of an increased flux of neutrinos, an alert

13674-464: The Supernova Early Warning System (SNEWS), where they search for an increase of neutrino flux that could signal a supernova event. There are currently goals to detect neutrinos from other sources, such as active galactic nuclei (AGN), as well as gamma-ray bursts and starburst galaxies . Neutrino astronomy may also indirectly detect dark matter. Seven neutrino experiments (Super-K, LVD, IceCube, KamLAND, Borexino , Daya Bay, and HALO) work together as

13833-543: The addition of a collective suffix (a noun suffix that indicates a group), such as -tachi , but this is not a true plural: the meaning is closer to the English phrase "and company". A group described as Tanaka-san-tachi may include people not named Tanaka. Some Japanese nouns are effectively plural, such as hitobito "people" and wareware "we/us", while the word tomodachi "friend" is considered singular, although plural in form. Verbs are conjugated to show tenses, of which there are two: past and present (or non-past) which

13992-529: The atmosphere. As these hadrons decay, they produce neutrinos (called atmospheric neutrinos). At low energies, the flux of atmospheric neutrinos is many times greater than astrophysical neutrinos. At high energies, the pions and kaons have a longer lifetime (due to relativistic time dilation). The hadrons are now more likely to interact before they decay. Because of this, the astrophysical neutrino flux will dominate at high energies (~100TeV). To perform neutrino astronomy of high-energy objects, experiments rely on

14151-401: The atmosphere; only some of the highest-energy muons are able to penetrate to the depths of our detectors. Detectors must include ways of dealing with data from muons so as to not confuse them with neutrinos. Along with more complicated measures, if a muon track is first detected outside of the desired "fiducial" volume, the event is treated as a muon and not considered. Ignoring events outside

14310-674: The atmospheric muon flux. The proof of concept will be implemented in the KM3Net framework. The second generation of deep-sea neutrino telescope projects reach or even exceed the size originally conceived by the DUMAND pioneers. IceCube , located at the South Pole and incorporating its predecessor AMANDA, was completed in December 2010. It currently consists of 5160 digital optical modules installed on 86 strings at depths of 1450 to 2550 m in

14469-416: The background. While it may be unknown if an individual event is background or signal, it is possible to detect an excess about the background, signifying existence of the desired signal. When astronomical bodies, such as the Sun , are studied using light, only the surface of the object can be directly observed. Any light produced in the core of a star will interact with gas particles in the outer layers of

14628-413: The barrel wall, giving the OD a total mass of 18 kilotons. OD PMTs were distributed with 302 on the top layer, 308 on the bottom, and 1275 on the barrel wall. To protect against low energy background radiation from radon decay products in the air, the roof of the cavity and the access tunnels were sealed with a coating called Mineguard. Mineguard is a spray-applied polyurethane membrane developed for use as

14787-430: The center of the Sun, take millions of years to reach the surface; on the other hand, solar neutrinos arrive at the earth in eight minutes due to their lack of interactions with matter. Hence, solar neutrinos make it possible for us to observe the inner Sun in "real-time" that takes millions of years for visible light. In 1999, the Super-Kamiokande detected strong evidence of neutrino oscillation that successfully explained

14946-405: The charged resultants are moving fast enough, they can create Cherenkov light . To observe neutrino interactions, detectors use photomultiplier tubes (PMTs) to detect individual photons. From the timing of the photons, it is possible to determine the time and place of the neutrino interaction. If the neutrino creates a muon during its interaction, then the muon will travel in a line, creating

15105-531: The charged-current contribution to ν e {\displaystyle \nu _{e}} scattering, has a relative sensitivity to ν e {\displaystyle \nu _{e}} s and heavy-flavor neutrinos of ~7:1. Since the direction of the recoil electron is constrained to be very forward, the direction of the neutrinos are kept in the direction of recoil electrons. Here, cos ⁡ θ S u n {\displaystyle \cos \theta _{Sun}}

15264-411: The data obtained from seismic and gravitational data. With the current data, the uncertainties on these values are still large, but future data from IceCube and KM3NeT will place tighter restrictions on this data. Neutrinos can either be primary cosmic rays (astrophysical neutrinos), or be produced from cosmic ray interactions. In the latter case, the primary cosmic ray will produce pions and kaons in

15423-408: The decay of particles resulting from interactions of primary cosmic rays (mostly protons ) with Earth atmosphere . The observed atmospheric neutrino events fall into four categories. Fully contained (FC) events have all their tracks in the inner detector, while partially contained (PC) events have escaping tracks from the inner detector. Upward through-going muons (UTM) are produced in the rock beneath

15582-472: The detection of antineutrinos from supernova explosions. The Super-Kamiokande (SK) is a Cherenkov detector used to study neutrinos from different sources including the Sun, supernovae, the atmosphere, and accelerators. It is also used to search for proton decay. The experiment began in April 1996 and was shut down for maintenance in July 2001, a period known as "SK-I". Since an accident occurred during maintenance,

15741-514: The detector and go through the inner detector. Upward stopping muons (USM) are also produced in the rock beneath the detector, but stop in the inner detector. Japanese language Japanese ( 日本語 , Nihongo , [ɲihoŋɡo] ) is the principal language of the Japonic language family spoken by the Japanese people . It has around 123 million speakers, primarily in Japan ,

15900-607: The detector is a 100-ton scintillation tank with dimensions on the order of the length of an electromagnetic shower with an initial energy of 100 GeV. After the decline of DUMAND the participating groups split into three branches to explore deep sea options in the Mediterranean Sea. ANTARES was anchored to the sea floor in the region off Toulon at the French Mediterranean coast. It consists of 12 strings, each carrying 25 "storeys" equipped with three optical modules, an electronic container, and calibration devices down to

16059-483: The detector that R mean {\displaystyle {R_{\text{mean}}}} for SN events should be significantly larger than for ordinary spatial clusters of events. In the Super-Kamiokande detector, R mean {\displaystyle {R_{\text{mean}}}} for uniformly distributed Monte Carlo events shows that no tail exists below R mean {\displaystyle {R_{\text{mean}}}} ⩽1000 cm. For

16218-535: The detector to its original form by reinstalling about 6,000 PMTs. The work was completed in June 2006, whereupon the detector was renamed Super-Kamiokande-III. This phase of the experiment collected data from October 2006 till August 2008. At that time, significant upgrades were made to the electronics. After the upgrade, the new phase of the experiment has been referred to as Super-Kamiokande-IV. SK-IV collected data on various natural sources of neutrinos, as well as acted as

16377-402: The detectors from cosmic rays, which can penetrate hundreds of meters of rock. Neutrinos, on the other hand, can go through the entire planet without being absorbed, like "ghost particles". That's why neutrino detectors are placed many hundreds of meter underground, usually at the bottom of mines. There a neutrino detection liquid such as a Chlorine-rich solution is placed; the neutrinos react with

16536-578: The effect of changing Japanese into a mora-timed language. Late Middle Japanese covers the years from 1185 to 1600, and is normally divided into two sections, roughly equivalent to the Kamakura period and the Muromachi period , respectively. The later forms of Late Middle Japanese are the first to be described by non-native sources, in this case the Jesuit and Franciscan missionaries; and thus there

16695-403: The emission of neutrinos. Beta decay in the Earth and in supernovas turns neutrons into protons with the emission of anti-neutrinos. The Super-Kamiokande detects electrons knocked off a water molecule producing a flash of blue Cherenkov light, and these are produced both by neutrinos and antineutrinos. A rarer instance is when an antineutrino interacts with a proton in water to produce a neutron and

16854-450: The energy of the neutrino from the interactions. The number of photons emitted is related to the neutrino energy, and neutrino energy is important for measuring the fluxes from solar and geo-neutrinos. Due to the rareness of neutrino interactions, it is important to maintain a low background signal. For this reason, most neutrino detectors are constructed under a rock or water overburden. This overburden shields against most cosmic rays in

17013-573: The experiment resumed in October 2002 with only half of its original number of ID-PMTs. In order to prevent further accidents, all of the ID-PMTs were covered by fiber-reinforced plastic with acrylic front windows. This phase from October 2002 to another closure for an entire reconstruction in October 2005 is called "SK-II". In July 2006, the experiment resumed with the full number of PMTs and stopped in September 2008 for electronics upgrades. This period

17172-524: The far detector for the Tokai-to-Kamioka (T2K) long baseline neutrino oscillation experiment. SK-IV continued until June 2018. After that, the detector underwent a full refurbishment during Autumn of 2018. On 29 January 2019 the detector resumed data acquisition. In 2020, the detector was upgraded for the SuperKGd project by adding a Gadolinium salt to the ultrapure water in order to enable

17331-401: The fiducial volume also decreases the signal from radiation outside the detector. Despite shielding efforts, it is inevitable that some background will make it into the detector, many times in the form of radioactive impurities within the detector itself. At this point, if it is impossible to differentiate between the background and true signal, a Monte Carlo simulation must be used to model

17490-423: The first appearance of European loanwords . The basis of the standard dialect moved from the Kansai region to the Edo region (modern Tokyo ) in the Early Modern Japanese period (early 17th century–mid 19th century). Following the end of Japan's self-imposed isolation in 1853, the flow of loanwords from European languages increased significantly, and words from English roots have proliferated. Japanese

17649-465: The first evidence of neutrino oscillation in 1998. This was the first experimental observation supporting the theory that the neutrino has non-zero mass , a possibility that theorists had speculated about for years. The 2015 Nobel Prize in Physics was awarded to Super-Kamiokande researcher Takaaki Kajita alongside Arthur McDonald at the Sudbury Neutrino Observatory for their work confirming neutrino oscillation. On 12 November 2001, about 6,600 of

17808-620: The first time evidence of CNO neutrinos in the Sun. Improvements on the CNO measurement will be especially helpful in determining the Sun's metallicity. The interior of Earth contains radioactive elements such as K 40 {\displaystyle {\ce {^{40}K}}} and the decay chains of U 238 {\displaystyle {\ce {^{238}U}}} and Th 232 {\displaystyle {\ce {^{232}Th}}} . These elements decay via Beta decay , which emits an anti-neutrino. The energies of these anti-neutrinos are dependent on

17967-462: The first time that the Sun was a source of neutrinos. While making discoveries in neutrino astronomy and neutrino astrophysics, Kamiokande never detected a proton decay, the primary goal for its construction. The absence of any such observation pushed back the possible half-life of any potential proton decay far enough to eliminate some of the GUT models which allow for such a decay. Other models predict

18126-545: The gadolinium at the same time. A 200-ton prototype called EGADS with added gadolinium sulfate was installed in the Kamioka mine and operated for years. It finished operation in 2018 and showed that the new water purification system would remove impurities while keeping the gadolinium concentration stable. It also showed that gadolinium sulfate would not significantly impair the transparency of the otherwise ultrapure water, or cause corrosion or deposition on existing equipment or on

18285-609: The genitive particle ga remains in intentionally archaic speech. Early Middle Japanese is the Japanese of the Heian period , from 794 to 1185. It formed the basis for the literary standard of Classical Japanese , which remained in common use until the early 20th century. During this time, Japanese underwent numerous phonological developments, in many cases instigated by an influx of Chinese loanwords . These included phonemic length distinction for both consonants and vowels , palatal consonants (e.g. kya ) and labial consonant clusters (e.g. kwa ), and closed syllables . This had

18444-400: The geomagnetic field. When any deviation from norms is detected, it will alert physicists to prompt to investigate, take appropriate action, or notify experts. To monitor and control the offline processes that analyze and transfer data, a sophisticated set of software was developed. This monitor allows non-expert shift physicists to identify and repair common problems to minimize down time, and

18603-627: The help of an international team. It is located 1,000 m (3,300 ft) underground in the Mozumi Mine in Hida's Kamioka area. The observatory was designed to detect high-energy neutrinos, to search for proton decay , study solar and atmospheric neutrinos , and keep watch for supernovae in the Milky Way Galaxy . Super-K is located 1,000 m (3,300 ft) underground in the Mozumi Mine in Hida's Kamioka area. It consists of

18762-424: The highest energy neutrinos. To perform astronomy of distant objects, a strong angular resolution is required. Neutrinos are electrically neutral and interact weakly, so they travel mostly unperturbed in straight lines. If the neutrino interacts within a detector and produces a muon, the muon will produce an observable track. At high energies, the neutrino direction and muon direction are closely correlated, so it

18921-410: The incoming neutrino is determined. From the sharpness of the edge of the ring the type of particle can be inferred. The multiple scattering of electrons is large, so electromagnetic showers produce fuzzy rings. Highly relativistic muons , in contrast, travel almost straight through the detector and produce rings with sharp edges. Construction of the predecessor of the present Kamioka Observatory ,

19080-490: The initial assembly of the ID. Each supermodule was assembled on the tank floor and then hoisted into its final position. Thus the ID is in effect tiled with supermodules. During installation, ID PMTs were pre-assembled in units of three for easy installation. Each supermodule has two OD PMTs attached on its back side. The support structure for the bottom PMTs is attached to the bottom of the stainless-steel tank by one vertical beam per supermodule frame. The support structure for

19239-458: The languages of the original Jōmon inhabitants, including the ancestor of the modern Ainu language . Because writing had yet to be introduced from China, there is no direct evidence, and anything that can be discerned about this period must be based on internal reconstruction from Old Japanese , or comparison with the Ryukyuan languages and Japanese dialects . The Chinese writing system

19398-449: The languages. Okinawan Japanese is a variant of Standard Japanese influenced by the Ryūkyūan languages, and is the primary dialect spoken among young people in the Ryukyu Islands . Modern Japanese has become prevalent nationwide (including the Ryūkyū islands) due to education , mass media , and an increase in mobility within Japan, as well as economic integration. Japanese is a member of

19557-427: The large quantity of English loanwords, modern Japanese has developed a distinction between [tɕi] and [ti] , and [dʑi] and [di] , with the latter in each pair only found in loanwords. Although Japanese is spoken almost exclusively in Japan, it has also been spoken outside of the country. Before and during World War II , through Japanese annexation of Taiwan and Korea , as well as partial occupation of China ,

19716-613: The most common particles in the universe. Because of this, neutrinos offer a unique opportunity to observe processes that are inaccessible to optical telescopes , such as reactions in the Sun's core. Neutrinos that are created in the Sun’s core are barely absorbed, so a large quantity of them escape from the Sun and reach the Earth. Neutrinos can also offer a very strong pointing direction compared to charged particle cosmic rays. Neutrinos are very hard to detect due to their non-interactive nature. In order to detect neutrinos, scientists have to shield

19875-543: The neutrino interacts with a nucleus or electron and the neutrino retains its original flavor. In charged-current interactions, the neutrino is absorbed by the nucleus and produces a lepton corresponding to the neutrino's flavor ( ν e ⟶ e − {\displaystyle {\ce {\nu_{e}-> e^-}}} , ν μ ⟶ μ − {\displaystyle {\ce {\nu_{\mu}-> \mu^{-}}}} , etc.). If

20034-446: The neutrino passed along its path, which is directly related to density. If the initial flux is known (as it is in the case of atmospheric neutrinos), then detecting the final flux provides information about the interactions that occurred. The density can then be extrapolated from knowledge of these interactions. This can provide an independent check on the information obtained from seismic data. In 2018, one year worth of IceCube data

20193-468: The new valves that will later be installed in the Hyper-Kamiokande . The outer shell of the water tank is a cylindrical stainless-steel tank 39 m in diameter and 42 m in height. The tank is self-supporting, with concrete backfilled against the rough-hewn stone walls to counteract water pressure when the tank is filled. The capacity of the tank exceeds 50 kilotonnes of water. The basic unit for

20352-407: The observation of 79 neutrinos with an energy over 1 TeV originated from the nearby galaxy M77 . These findings in a well-known object are expected to help study the active nucleus of this galaxy, as well as serving as a baseline for future observations. In June 2023, astronomers reported using a new technique to detect, for the first time, the release of neutrinos from the galactic plane of

20511-411: The only bodies that have been studied in this way are the sun and the supernova SN1987A, which exploded in 1987. Scientist predicted that supernova explosions would produce bursts of neutrinos, and a similar burst was actually detected from Supernova 1987A. In the future neutrino astronomy promises to discover other aspects of the universe, including coincidental gravitational waves , gamma ray bursts ,

20670-554: The only country where it is the national language , and within the Japanese diaspora worldwide. The Japonic family also includes the Ryukyuan languages and the variously classified Hachijō language . There have been many attempts to group the Japonic languages with other families such as the Ainu , Austronesian , Koreanic , and the now-discredited Altaic , but none of these proposals have gained any widespread acceptance. Little

20829-425: The only strict rule of word order is that the verb must be placed at the end of a sentence (possibly followed by sentence-end particles). This is because Japanese sentence elements are marked with particles that identify their grammatical functions. The basic sentence structure is topic–comment . For example, Kochira wa Tanaka-san desu ( こちらは田中さんです ). kochira ("this") is the topic of the sentence, indicated by

20988-470: The out-group gives a benefit to the in-group, and "up" to indicate the in-group gives a benefit to the out-group. Here, the in-group includes the speaker and the out-group does not, and their boundary depends on context. For example, oshiete moratta ( 教えてもらった ) (literally, "explaining got" with a benefit from the out-group to the in-group) means "[he/she/they] explained [it] to [me/us]". Similarly, oshiete ageta ( 教えてあげた ) (literally, "explaining gave" with

21147-443: The parent nucleus. Therefore, by detecting the anti-neutrino flux as a function of energy, we can obtain the relative compositions of these elements and set a limit on the total power output of Earth's geo-reactor. Most of our current data about the core and mantle of Earth comes from seismic data, which does not provide any information as to the nuclear composition of these layers. Borexino has detected these geo-neutrinos through

21306-415: The particle wa . The verb desu is a copula , commonly translated as "to be" or "it is" (though there are other verbs that can be translated as "to be"), though technically it holds no meaning and is used to give a sentence 'politeness'. As a phrase, Tanaka-san desu is the comment. This sentence literally translates to "As for this person, (it) is Mx Tanaka." Thus Japanese, like many other Asian languages,

21465-522: The photomultiplier tubes, costing about $ 3,000 each, in the Super-Kamiokande detector imploded , apparently in a chain reaction or cascading failure , as the shock wave from the concussion of each imploding tube cracked its neighbours. The detector was partially restored by redistributing the photomultiplier tubes which did not implode, and by adding protective acrylic shells that are hoped will prevent another chain reaction from recurring (Super-Kamiokande-II). In July 2005, preparations began to restore

21624-449: The process ν ¯ + p + ⟶ e + + n {\displaystyle {\ce {{\bar {\nu }}+p^{+}\longrightarrow e^{+}{+n}}}} . The resulting positron will immediately annihilate with an electron and produce two gamma-rays each with an energy of 511keV (the rest mass of an electron). The neutron will later be captured by another nucleus, which will lead to

21783-457: The proposal by Moisey Markov in 1960 "...to install detectors deep in a lake or a sea and to determine the location of charged particles with the help of Cherenkov radiation ." The first underwater neutrino telescope began as the DUMAND project. DUMAND stands for Deep Underwater Muon and Neutrino Detector. The project began in 1976 and although it was eventually cancelled in 1995, it acted as

21942-481: The proposed larger Altaic family, or to various Southeast Asian languages , especially Austronesian . None of these proposals have gained wide acceptance (and the Altaic family itself is now considered controversial). As it stands, only the link to Ryukyuan has wide support. Other theories view the Japanese language as an early creole language formed through inputs from at least two distinct language groups, or as

22101-426: The readout of multiple sequential hits that may arise, e.g. from electrons that are decay products of stopping muons. The SK system was upgraded in September 2008 in order to maintain the stability in the next decade and improve the throughput of the data acquisition systems, QTC-based electronics with Ethernet (QBEE). The QBEE provides high-speed signal processing by combining pipelined components. These components are

22260-438: The remaining tank volume. Mounted on the superstructure are 11,146 photomultiplier tubes (PMT) 50 cm (20 in) in diameter that face the ID and 1,885 20 cm (8 in) PMTs that face the OD. There is a Tyvek and blacksheet barrier attached to the superstructure that optically separates the ID and OD. A neutrino interaction with the electrons or nuclei of water can produce a charged particle that moves faster than

22419-459: The same structure as affirmative sentences, but with intonation rising at the end. In the formal register, the question particle -ka is added. For example, ii desu ( いいです ) "It is OK" becomes ii desu-ka ( いいですか。 ) "Is it OK?". In a more informal tone sometimes the particle -no ( の ) is added instead to show a personal interest of the speaker: Dōshite konai-no? "Why aren't (you) coming?". Some simple queries are formed simply by mentioning

22578-403: The software package was a significant contribution to the smooth operation of the experiment and its overall high lifetime efficiency for data taking. The energy of the Sun comes from the nuclear fusion in its core where a helium atom and an electron neutrino are generated by 4 protons. These neutrinos emitted from this reaction are called solar neutrinos. Photons, created by the nuclear fusion in

22737-402: The star, taking hundreds of thousands of years to make it to the surface, making it impossible to observe the core directly. Since neutrinos are also created in the cores of stars (as a result of stellar fusion ), the core can be observed using neutrino astronomy. Other sources of neutrinos- such as neutrinos released by supernovae- have been detected. Several neutrino experiments have formed

22896-817: The state as at the time the constitution was written, many of the elders participating in the process had been educated in Japanese during the South Seas Mandate over the island shown by the 1958 census of the Trust Territory of the Pacific that found that 89% of Palauans born between 1914 and 1933 could speak and read Japanese, but as of the 2005 Palau census there were no residents of Angaur that spoke Japanese at home. Japanese dialects typically differ in terms of pitch accent , inflectional morphology , vocabulary , and particle usage. Some even differ in vowel and consonant inventories, although this

23055-481: The street. (grammatically incorrect insertion of a pronoun) But one can grammatically say essentially the same thing in Japanese: 驚いた彼は道を走っていった。 Transliteration: Odoroita kare wa michi o hashitte itta. (grammatically correct) This is partly because these words evolved from regular nouns, such as kimi "you" ( 君 "lord"), anata "you" ( あなた "that side, yonder"), and boku "I" ( 僕 "servant"). This

23214-528: The top of the tank is also used as the support structure for the top PMTs. Cables from each group of 3 PMTs are bundled together. All cables run up the outer surface of the PMT support structure, i.e., on the OD PMT plane, pass through cable ports at the top of the tank, and are then routed into the electronics huts. The thickness of the OD varies slightly, but is on average about 2.6 m on top and bottom, and 2.7 m on

23373-653: The topic with an interrogative intonation to call for the hearer's attention: Kore wa? "(What about) this?"; O-namae wa? ( お名前は？ ) "(What's your) name?". Negatives are formed by inflecting the verb. For example, Pan o taberu ( パンを食べる。 ) "I will eat bread" or "I eat bread" becomes Pan o tabenai ( パンを食べない。 ) "I will not eat bread" or "I do not eat bread". Plain negative forms are i -adjectives (see below) and inflect as such, e.g. Pan o tabenakatta ( パンを食べなかった。 ) "I did not eat bread". Neutrino astronomy Neutrinos are nearly massless and electrically neutral or chargeless elementary particles . They are created as

23532-419: The two consonants are the moraic nasal followed by a homorganic consonant. Japanese also includes a pitch accent , which is not represented in moraic writing; for example [haꜜ.ɕi] ("chopsticks") and [ha.ɕiꜜ] ("bridge") are both spelled はし ( hashi ) , and are only differentiated by the tone contour. Japanese word order is classified as subject–object–verb . Unlike many Indo-European languages ,

23691-577: The two methods were both used in writing until the 1940s. Bungo still has some relevance for historians, literary scholars, and lawyers (many Japanese laws that survived World War II are still written in bungo , although there are ongoing efforts to modernize their language). Kōgo is the dominant method of both speaking and writing Japanese today, although bungo grammar and vocabulary are occasionally used in modern Japanese for effect. The 1982 state constitution of Angaur , Palau , names Japanese along with Palauan and English as an official language of

23850-480: The two terms (''hyōjungo'' and ''kyōtsūgo'') are almost the same. Hyōjungo or kyōtsūgo is a conception that forms the counterpart of dialect. This normative language was born after the Meiji Restoration ( 明治維新 , meiji ishin , 1868) from the language spoken in the higher-class areas of Tokyo (see Yamanote ). Hyōjungo is taught in schools and used on television and in official communications. It

24009-407: The verb (e.g. yonde for earlier yomite ), the -k- in the final mora of adjectives drops out ( shiroi for earlier shiroki ); and some forms exist where modern standard Japanese has retained the earlier form (e.g. hayaku > hayau > hayɔɔ , where modern Japanese just has hayaku , though the alternative form is preserved in the standard greeting o-hayō gozaimasu "good morning"; this ending

24168-548: The world. Since Japanese first gained the consideration of linguists in the late 19th century, attempts have been made to show its genealogical relation to languages or language families such as Ainu , Korean , Chinese , Tibeto-Burman , Uralic , Altaic (or Ural-Altaic ), Austroasiatic , Austronesian and Dravidian . At the fringe, some linguists have even suggested a link to Indo-European languages , including Greek , or to Sumerian . Main modern theories try to link Japanese either to northern Asian languages, like Korean or

24327-538: Was a Bombay-Osaka-Durham collaboration that operated in the Indian Kolar Gold Field mine at an equivalent water depth of 7.5 km. Although the KGF group detected neutrino candidates two months later than Reines CWI, they were given formal priority due to publishing their findings two weeks earlier. In 1968, Raymond Davis, Jr. and John N. Bahcall successfully detected the first solar neutrinos in

24486-539: Was based on 12- to 20-second-long recordings of 135 to 244 phonemes , which 42 students listened to and translated word-for-word. The listeners were all Keio University students who grew up in the Kanto region . There are some language islands in mountain villages or isolated islands such as Hachijō-jima island , whose dialects are descended from Eastern Old Japanese . Dialects of the Kansai region are spoken or known by many Japanese, and Osaka dialect in particular

24645-431: Was evaluated to perform neutrino tomography. The analysis studied upward going muons, which provide both the energy and directionality of the neutrinos after passing through the Earth. A model of Earth with five layers of constant density was fit to the data, and the resulting density agreed with seismic data. The values determined for the total mass of Earth, the mass of the core, and the moment of inertia all agree with

24804-735: Was imported to Japan from Baekje around the start of the fifth century, alongside Buddhism. The earliest texts were written in Classical Chinese , although some of these were likely intended to be read as Japanese using the kanbun method, and show influences of Japanese grammar such as Japanese word order. The earliest text, the Kojiki , dates to the early eighth century, and was written entirely in Chinese characters, which are used to represent, at different times, Chinese, kanbun , and Old Japanese. As in other texts from this period,

24963-616: Was known as "SK-III". The period after 2008 is known as "SK-IV". The phases and their main characteristics are summarised in table 1. In the previous phases, the ID-PMTs processed signals by custom electronics modules called analog timing modules (ATMs). Charge-to-analog converters (QAC) and time-to-analog converters (TAC) are contained in these modules that had dynamic range from 0 to 450 picocoulombs (pC) with 0.2 pC resolution for charge and from −300 to 1000 ns with 0.4 ns resolution for time. There were two pairs of QAC/TAC for each PMT input signal, this prevented dead time and allowed

25122-474: Was lost immediately following its composition.) This set of morae shrank to 67 in Early Middle Japanese , though some were added through Chinese influence. Man'yōgana also has a symbol for /je/ , which merges with /e/ before the end of the period. Several fossilizations of Old Japanese grammatical elements remain in the modern language – the genitive particle tsu (superseded by modern no )

25281-667: Was upgraded, starting in 1985, to allow it to observe solar neutrinos. As a result, the detector (KamiokaNDE-II) had become sensitive enough to detect ten neutrinos from SN 1987A , a supernova which was observed in the Large Magellanic Cloud in February 1987, and to observe solar neutrinos in 1988. The ability of the Kamiokande experiment to observe the direction of electrons produced in solar neutrino interactions allowed experimenters to directly demonstrate for

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