In General > s.a. particle physics and types of particles / neutrino detectors and applications.
* History: 1930, Existence predicted by Pauli, who called it "neutron"; 1933 (after Chadwick's discovery of the n), it became Fermi's "neutrino"; 1938, H Bethe, nuclear reaction in the Sun; 1953, νe discovered by Reines & Cowan; 1962, First neutrino beam at BNL and νμ discovered; 1969, Gribov and Pontecorvo's solution of solar neutrino puzzle, elaborated on later by Wolfenstein and Mikheyev & Smirnov; 1975, ντ discovered by Perl; 1989, There are only 3 light neutrinos (m < mZ/2), from the Z line shape; 1998, Evidence for oscillations from Super-Kamiokande; 2002, Evidence reported for neutrinoless double-β decay 2n → 2p + 2e (implies lepton number violation, mν value); 2003, They are candidates for hot dark matter but cannot account for most of the dark matter even if massive, because of constraints from large-scale structure; 2016, Neutrino research a growing field, with expectation that neutrinos hold the key to expanding the standard model; 2018, MiniBooNE data are incompatible with oscillations involving just the three known neutrino flavors.
* Interactions: With a q, it can exchange a W (charged current, ν turns into an e or μ, as in νe + dp + n + e), or a Z (neutral current, ν remains, as in ν + dp + n + ν ); can be used to measure the weak mixing angle.
* Open issues: Do νs and ν-bars have the same masses? If not, this could signal CPT violation; Are neutrinos Dirac or Majorana spinors? Confirmation of neutrinoless double-beta decay would imply that they are their own antiparticles, and therefore Majorana particles; > s.a. neutron.
@ History: Franklin PT(00)feb; Bilenky phy/01, MPLA(04) [and status]; Pietschmann phy/06-ln; # B Pontecorvo; focus Phy(07) [1953 νe discovery]; Zralek APPB(10)-a1012-ln; Steinberger AP(12); focus Phy(15) [1962 νμ discovery]; Rajasekaran a1606; Recami HJ-a1712 [Majorana]; Blondel a1812-conf [ντ]; Goodman a1901-proc ["mistakes"]; Ramond a1902-conf; Rodriguez a1907-conf.
@ Books: Sutton 92; Winter 00; Giunti & Kim 07; Zuber 11 [r CP(12)#1, e1 PT(05)apr].
@ General references, reviews: Witten TPT(83)feb [masses, detection]; Sarma IJMPA(95); Reines RMP(96); Haxton & Holstein AJP(00)jan, AJP(04)jan; Akhmedov NPPS(01); González-García & Nir RMP(03)hp/02; Roulet ap/04-ln [phenomenology]; Aničin phy/05-in; Maricic & Learned CP(05) [specially oscillations]; Wark pw(05)jun; Strumia & Vissani hp/06; Xing IJMPA(08); Winter NPPS(10); Brugnera IJMPA(11); Barger et al 12; Zukanovich Funchal et al a1308-ln; Lincoln & Miceli TPT(15); Aguilar-Arevalo & Bietenholz RCF-a1601; news pt(16)aug [excitement about neutrino physics]; Spurio GdF-a1609; Goodman AJP(16)dec [RL]; Kopp Phy(18) [viewpoint on 4th neutrino status]; news APS(19)may [status].

Masses > s.a. mixing and oscillations; types of neutrinos [including Dirac vs Majorana, and superluminal].
* Theory: Theoretical values are largely unknown; In the standard model, all neutrinos are massless, but we know from oscillations that (at least two) have non-zero masses; GUTs require non-zero masses, but they don't predict their values; However, oscillation experiments only probe differences between squared masses, and do not give values for individual masses; The "neutrino mass hierarchy problem" is the question whether m2 is lighter than m3 (normal hierarchy) or heavier (inverted hierarchy).
* Bounds on masses: 1998, The neutrino is not massless, based on evidence for neutrino oscillations; 2010, Galaxy survey gives that the sum of all neutrino masses < 0.28 eV (95% CL) in flat ΛCDM cosmology; 2019, KATRIN (Karlsruhe Tritium Neutrino) experiment gives 1.1 eV as upper bound on the neutrino mass [cosmos(19)sep; Brugnera Phys(19)]; 2021, new KATRIN bound is 0.8 eV [sn(21)apr].
@ General references: Wolfenstein CP(96); Zuber PRP(98), Valle hp/98-proc [rev]; Divakaran & Rajasekaran MPLA(99) [proposal]; Akhmedov NPPS(00)hp [seesaw]; Bilenky et al PRP(03); McKeown & Vogel PRP(04) [and oscillations]; Giedt et al PRD(05)ht [string theory]; King CP(07) [rev]; news pw(10)jun [evidence for different neutrino and antineutrino masses]; Simpson et al JCAP(17)-a1703 [strong evidence for the normal hierarchy].
@ And cosmology: Elgarøy et al PRL(02) [2dF]; Kainulainen & Olive ap/02; Abazajian & Dodelson PRL(03) [weak lensing]; Elgarøy & Lahav JCAP(03) [2dF and WMAP]; Hannestad PRD(02), JCAP(03) [WMAP & 2dF], & Raffelt JCAP(04); Kaplinghat et al PRL(03) [cmb]; Tegmark et al PRD(05)ap/03 [anthropic]; Brandenberger et al PRD(04) [robustness]; Crotty et al PRD(04); Lesgourgues et al PRD(04) [redshift surveys]; Ichikawa et al PRD(05) [cmb only]; Melchiorri et al NPPS(05)ap; Kahniashvili et al PRD(05)ap, Wang et al PRL(05)ap [galaxy cluster surveys]; Hannestad PRL(05)ap [and dark energy equation of state], & Raffelt JCAP(06)ap-in; Slosar PRD(06)ap; Goobar et al JCAP(06); Lesgourgues & Pastor PRP(06); Elgarøy NPPS(07)hp/06; Zunckel & Ferreira JCAP(07); De Bernardis et al PRD(08)-a0809, PRD(09)-a0907; Banhatti a0901 [bounds, and equivalence principle]; Kawasaki & Sato PTP(09)-a0907; Sekiguchi et al JCAP(10) [and high-accuracy measurement of the Hubble constant]; Thomas et al PRL(10) + Lesgourgues Phy(10) [galaxy surveys]; Hannestad PPNP(10)-a1007 [rev]; Jose et al PRD(11) [from high-redshift galaxy luminosity functions]; Shimon et al MNRAS(12)-a1201 [SZ surveys]; Hamann et al JCAP(12)-a1209 [galaxy surveys]; Lesgourgues & Pastor AHEP(12)-a1212; Burenin AL(13)-a1301; Battye & Moss PRL(14) [cmb and lensing]; Wolk a1503, Gerbino et al PRD(16)-a1507, Huang et al EPJC(16)-a1512 [improving constraints]; Vagnozzi et al PRD(17)-a1701; Couchot et al A&A(17)-a1703; Wang et al ChPC(18)-a1707.
@ And supernovae: Lunardini & Smirnov JCAP(03); Dighe et al JCAP(03) [IceCube].
@ Theory: Arkani-Hamed et al PRD(02) [higher-dimensional, 10−1–10−4 eV]; Mohapatra NJP(04) [rev]; Berezinsky et al JHEP(05) [and low-scale gravity]; Lambiase et al CQG(06)gq/05 [lower bound, geometric quantum mechanics and SN1987A]; Sharatchandra a0710 [from quantum gravity attractions]; Mavromatos a1506-conf [unconventional scenarios, Lorentz-symmnetry violation and torsion]; Dvali & Funcke PRD(16)-a1607 [from a gravitational θ term]; Asselmeyer-Maluga & Król MPLA(19)-a1801 [and exotic smoothness]; Carneiro a1811 [from minimal length]; > s.a. standard model; non-commutative gauge theories.

Other Properties and Processes > s.a. Fluorine.
@ Magnetic dipole moment: Vysotsky MPLA(03) [theory]; MUNU Collaboration PLB(03) [exp]; Bell IJMPA(07), Novello & Bittencourt IJMPA(14)-a1111 [theory]; Viaux et al A&A(13)-a1308 [and the globular cluster M5].
@ Neutrinoless double-beta decay: Feder PT(10)jan; Bilenky & Giunti MPLA(12) [rev]; news sn(18)feb [experiments]; Engel & Vogel Phy(18).

Theoretical Issues and Other Topics > s.a. composite models; matter; neutrinos in astrophysics; spin-statistics; Superfluids.
@ Propagation: Elizalde et al PRD(04)hp [strongly magnetized media]; Kuznetsov et al PRD(06) [dispersion in external magnetic field]; Bravo & Sahu MPLA(07) [in media, self-energy corrections]; Millhouse & Latimer AJP(13)sep [through matter]; Vlasenko et al PRD(14)-a1309, Cirigliano et al PLB(15)-a1406 [in hot, dense media]; Volpe IJMPE(15)-a1506 [in media, evolution equations based on the mean-field, extended mean-field and Boltzmann equations]; Zhang EPJP(17)-a1803 [in curved spacetime].
@ CPT violation: Barenboim et al PLB(02), PLB(02); Bahcall et al PLB(02)hp; news sn(10)jun [possible antineutrino-neutrino asymmetry].
@ New physics: Hirsch et al SA(13)apr; Archidiacono & Hannestad JCAP(14)-a1311 [constraints on non-standard interactions].
@ In gravitational fields: Nieves & Pal MPLA(99)gq [general relativity coupling]; Lambiase et al PRD(05)gq; Mukhopadhyay MPLA(05)ap [asymmetry around black holes]; > s.a. quantum-gravity phenomenology.
@ Related topics: Sciama ASS(01)ap/97 [decaying neutrino and ISM ionization]; Casini et al PRD(99) [and gravity]; Kaplan et al PRL(04) [varying masses and dark energy]; Giunti & Studenikin PAN(09)-a0812 [electromagnetic properties]; Goldhaber & Goldhaber PT(11)may [elusive helicity reversal]; Fujikawa & Tureanu MPLA(15)-a1507 [neutrino-antineutrino mass splitting]; Costantino & Fichet JHEP(20)-a2003 [neutrino Casimir force]; > s.a. Double-Beta Decay.

"The earth is just a silly ball / To them, through which they simply pass." – John Updike.

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