Types and Models of Neutrinos  

In General > s.a. mixing and oscillations; neutrinos [interactions]; dirac fields; kerr spacetime; Singletons.
* e-neutrinos: 1986, Bethe estimates m = 2 × 10−7 eV, based on oscillations; Bahcall & Glashow give m < 9.5 eV from SN 1987A data; 2002, 3H decay experiments give m < 2.2 eV; 2003, m < 0.6 eV, 95% cl, from SDSS data; WMAP gives m < 0.7 eV.
* μ-neutrinos: 1986, Bethe estimates m = 0.01 eV, from oscillations; 1995, m < 160 KeV, 95%, from particle decay rates; 2002, 2dF results on galaxy distribution power spectrum imply me + mμ + mτ < 2.2 eV.
* τ-neutrinos: 1978, Theorized by M Perl; 2000, Direct evidence at Fermilab; 1995, m < 29 MeV, 95%, from decay rates.
* Geoneutrinos: The Earth emits about 1025 geoneutrinos per second, roughly a trillionth of the solar neutrinos, from radioactive decays in the mantle and crust.
@ Number of species: Herbut a1211 [massive Majorana chiral neutrinos, time reversal symmetry, and the dimension of space]; news cosmos(18)sep [evidence for a fourth type?]; > s.a. cosmological neutrinos.
@ Dirac vs Majorana: Gutierrez PRL(06) [experiment proposal]; Singh et al PRL(06)gq, gq/06, comment Nieves & Pal PRL(07)gq/06, reply PRL(07)gq/06 [gravity coupling]; Dvoeglazov a1108-conf [chirality and helicity]; Ackerman et al PRL(11) [improved understanding of two-neutrino double-beta decay]; Alavi & Abbasnezhad G&C(16)-a1201 [and interaction with gravity]; news lbl(12)may [MAJORANA DEMONSTRATOR experiment]; Dib & Kim PRD(15) [and W boson decays]; Romero MPLA(16)-a1605 [argument for Majorana].
@ 17 keV neutrinos: news PT(91)may, PT(93)apr; Franklin RMP(95) [consensus is that it is not there]; Wietfeldt & Norman PRP(96).
@ Atmospheric neutrinos: Plyaskin PLB(01); Gaisser PS(05)ap [rev]; Stanev NPPS(05); González-García et al PRL(08)-a0711 + news pw(07)nov [as probes of Earth interior]; Gaisser JPCS(16)-a1605 [rev]; LoSecco PiP(16)-a1606 [history].
@ Geoneutrinos: news pi(10)jul [search]; focus Phy(15) [neutrinos from Earth's mantle detected by Borexino]; Agostini et Borexino PRD(20).
@ Related topics: Barger et al PLB(11)-a1010 [models with 3 layers of neutrinos]; McDonough et al PT(12)mar [uses of anti-νes]; Sidharth IJTP(13) [model].

Sterile Neutrinos
* Idea: Hypothetical particles with keV masses, which interact only gravitationally and decay over a very long time, much longer than the Hubble time; The motivation is that three neutrinos don't seem to explain all oscillation (atmospheric, solar, accelerator) data; However, there are Super-Kamiokande indications that νμντ exclusively, and not into sterile ones.
* Status: 2007, MiniBooNE results provide evidence for only three light neutrinos and make sterile neutrinos unlikely [@ news pn(07)apr]; 2011, New experiments have revealed evidence that sterile neutrinos are not only real but common, and a possible component of dark matter.
@ General references: Patel & Fuller hp/00-proc; Fukuda et al PRL(00); Volkas PPNP(02); Kusenko AIP(07)hp, PRP(09) [rev]; Chan & Chu ApJL(11)-a1009 [near the galactic center]; Giunti a1110-conf [phenomenology]; Nicolaidis MPLA(12) [resonance between flavor and sterile neutrino with large extra dimensions]; Kang IJMPA(19)-a1904 [in particle physics and cosmology].
@ Tests, experimental searches: news SA(11)jan; news PhysOrg(11)nov [proposed test]; news pw(13)jun [upcoming thorough search at Gran Sasso]; An et al PRL(14) [stringent limits from search at Daya Bay]; Lindner et al JHEP(16)-a1510 [in the light of IceCube]; Schmitz Phy(16), news nat(16)aug, pt(16)aug [IceCube finds no evidence]; news pt(18)jun [evidence from neutrino oscillations?]; news cosmos(18)nov [hints?]; news Phys(20) [stringent constraints].
@ And cosmology: Dodelson et al PRL(06); Joudaki et al PRD(13)-a1208; Bergström et al JHEP(14)-a1407 [tests]; Vincent et al JCAP(15)-a1408 [bounds]; Leistedt et al PRL(14) [sterile neutrinos do not reduce the discrepancy between cosmological data sets]; Gariazzo a1601-proc; > s.a. dark-matter types.

Superluminal Neutrinos? > s.a. particle physics and types of particles.
@ Theory: Giannetto et al PLB(86); Magueijo a1109 [and neutrino oscillations]; Contaldi a1109 [clock synchronisation issue?]; Hannestad & Sloth a1109 [sterile neutrinos in higher dimensions?]; Alexandre et al PLB(12)-a1109 [models]; Kehagias a1109 [local effect caused by a scalar field]; Cohen & Glashow PRL(11)-a1109 [electron-positron pair bremsstrahlung issue]; Giudice et al NPB(12) [interpretation and conflict]; Berry et al JPA(11)-a1110 [quantum weak measurement? probably not]; Altaie a1111 [torsion]; Amelino-Camelia et al IJMPD(11), MPLA(12); Santos a1201 [metric fluctuations]; Kirillov & Savelova a1204 [wormhole-like object?]; Hebecker & Knochel PLB(12) [constraints, difficulties]; Fujii IJGMP(13) [rev]; > s.a. finsler geometry; majorana spinors.
@ Experiment: OPERA, Adam et al JHEP(12)-a1109 + news cern(11)sep, sn(11)sep, bbc(11)sep, comment Close guardian(11)sep; Delmastro blog(11)sep; Drago et al EPL(12)-a1109; comments sa(11)sep; Henri a1110 [varying beam composition]; Mecozzi & Bellini a1110 [group velocity]; news pw(11)oct [differing opinions within OPERA]; pt(11)oct [reaction of the press]; van Elburg a1110 + tr(11)oct [relativistic motion of GPS clocks]; Icarus Collab PLB(12)-a1110 + news pw(11)oct [no electron-positron pairs]; Davoudiasl & Rizzo PRD(11)-a1110 [LHC tests]; Cowsik et al PRL(11) [and pion decay]; Bel a1112 [OPERA and the GPS]; news sn(11)dec [conservation of energy and momentum]; news nat(12)feb, sci(12)feb, pt(12)feb, ns(12)feb [loose fiber-optic cable?]; Antonello et al PLB(12)-a1203 + news bbc(12)mar [no longer superluminal in new experiment]; news nat(12)apr [project leaders step down]; news csm(12)jun [new results all consistent with the speed of light]; Zichichi IJMPA(12).

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