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Astroparficle,Physics,, With,Mev,Neutrinos University(of(Virginia,(HEP(Seminar,(April(21st(2015( Astropar(cle,physics,, with,MeV,neutrinos, Shunsaku(Horiuchi(( (Center(for(Neutrino(Physics,(Virginia(Tech)( Image(credit:(NASA/ESA( Contents, • IntroducJon:(why(astrophysical(neutrinos(now?( • Topic(1:(Supernova(neutrinos( – GalacJc(events:(rich(physics(and(astronomy( – Detectability(beyond(GalacJc(events( • Topic(2:(Dark(maPer(neutrinos( – Two(searches,(two(constraints( • Summary( UVa,(April(21st(2015( Shunsaku(Horiuchi((Virginia(Tech)( 2( Neutrinos,as,messenger,par(cles Neutrinos(are(great(messenger(parJcles:( • allow(us(to(see(opJcally(thick((to(photons)(regions( • experience(liPle(aPenuaJon(through(cosmic(space( • travel(in(straight(lines( Source Neutrinos gamma(rays( Cosmic(raysCosmic(rays( MagneJc(field UVa,(April(21st(2015 Shunsaku(Horiuchi((Virginia(Tech) 3( Neutrino,detec(on:,Cherenkov,, Use(the(Cherenkov(light(to(reconstruct(the(original(neutrino( ν" IceCube( Eν >(10(GeV( Muon(range(increases( the(effecJve(volume(( lepton( e( Du>a,et,al,,PRD,(2001),, SuperVKamiokande( Eν(>(few(MeV(( Volume(~(50(kton(of(water( Volume(~(1(Gton(of(ice( UVa,(April(21st(2015( Shunsaku(Horiuchi((Virginia(Tech)( 4( Neutrino,sources, RadioacJve(decay( Sun((x1)( Nuclear( Supernova((x1)( reactors( ParJcle( Astrophysical( accelerator( accelerator( Likely' Cosmic(background( Atmospheric( +(others?( UVa,(April(21st(2015(Shunsaku(Horiuchi((IPMU)((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((((Shunsaku(Horiuchi((Virginia(Tech)( 5(( The,neutrino,sky, ExtraVterrestrial(Sources:( • Big(bang(relics((~10V4(eV)( • Solar(neutrinos((~1(MeV)( • CoreVcollapse(supernova( neutrinos((~10(MeV)( • Atmospheric(neutrinos( • Neutrinos(from(cosmicVray( sources((GRBs,(AGNs)( • Cosmogenic(neutrinos( (~1015V1020(eV)( Terrestrial(sources( • Geothermal(neutrinos( • Reactor(neutrinos( • Accelerator(neutrinos( UVa,(April(21st(2015( Shunsaku(Horiuchi((Virginia(Tech)( 6( Some,big,ques(ons, Neutrinos(hold(the(key(to(solving(many(quesJons( • What,is,the,How,to,study,the,supernovaexplosion,mechanism,explosion,mechanism?, , • What,How,to,study,the,forma(on,of,nucleosynthesis,products,are,made?,black,holes, I(will(talk(about:( • How,do,How,to,test,the,nature,of,black,holes,form?,uncertain,transients, • When,are,jets,formed?, • Etc…,How,to,test,models,of,dark,ma>er, But(there(are(many(other(important(physics:( • What,are,the,proper(es,of,neutrinos?, • What,is,the,physics,at,high,temperature,and,density?, • Are,there,energy,sinks,due,to,new,par(cles?, • Where,are,cosmic,rays,accelerated?, • Can,we,refine,the,Solar,model?, • etc, UVa,(April(21st(2015( Shunsaku(Horiuchi((Virginia(Tech)( 7( SUPERNOVA*NEUTRINOS* -*GALACTIC*EVENTS*-** UVa,(April(21st(2015( Shunsaku(Horiuchi((Virginia(Tech)( 8( SN,1987A,in,the,LMC, Sanduleak(V69(202( SN(1987A(23(Feb(1987(( UVa,(April(21st(2015( Shunsaku(Horiuchi((Virginia(Tech)( 9( SN,1987A,in,the,LMC, 53 Massive(star((((((((((((~1.4Msun(core(((((((((Neutron(Star(( Energy(budget(~(3(x(10 (erg( Fe( n( 99%((((((((into(neutrinos( ((1%((((((((into(shock(KE( ((0.01%((into(photons( Sanduleak(V69(202( SN(1987A(23(Feb(1987(( UVa,(April(21st(2015( Shunsaku(Horiuchi((Virginia(Tech)( 10( SN,1987A,in,the,LMC, 53 Massive(star((((((((((((~1.4Msun(core(((((((((Neutron(Star(( Energy(budget(~(3(x(10 (erg( KamokandeVII( Fe( n( 99%((((((((into(neutrinos( ((1%((((((((into(shock(KE( ((0.01%((into(photons( IMB( Baksan( 24(neutrino(events(in(total( Sanduleak(V69(202( SN(1987A(23(Feb(1987(( Hirata,et,al,,PRL,(1987),,Bionta,et,al,(1987),,Alekseev,et,al,,PRL,(1987), UVa,(April(21st(2015( Shunsaku(Horiuchi((Virginia(Tech)( 11( Lessons,form,SN,1987A,neutrinos, Discovery(of(the(key(characterisJcs:( 1. The(thermal(nature(of(neutrinos((spectrum(&(duraJon)( 2. The(neutrino(temperature(( 3. The(total(binding(energy( (erg]( 53 Binding(energy([10 Spectral(temperature([MeV]( Yuksel,,&,Beacom,(2007), Adapted,from,Jegerlehner,,Neubig,&,Raffelt,(1996), UVa,(April(21st(2015( Shunsaku(Horiuchi((Virginia(Tech)( 12( Supernova,mechanism, The(problem:(the(bounce(shock(stalls(at(~150(km.(How(is(this(stalled(shock( revived?(This(is(the(“supernova(mechanism”( The(neutrino(mechanism:(( net(energy(deposiJon(in(the(gain( region(behind(the(shock( ( Wilson,(1985),,Bethe,&,Wilson,(1985),,,…( ( Cooling:( 6 ( Q⌫− T ( / ( + 2 2 HeaJng:( ( Q⌫ L⌫ r− ✏¯⌫ Gain(region( ( / But(this((mostly)(fails(in(1D((the( excepJon(is(small(mass(stars(with(OV NeVMg(cores)( ( MulJVdimensionality(and(fluid( instabiliJes(likely(play(a(central(role.( O>,,Burrow,,Dessart,&,Livne,(2008), UVa,(April(21st(2015( Shunsaku(Horiuchi((Virginia(Tech)( 13( Standing,Accre(on,Shock,Instability,(SASI), NonVradial(oscillatory(shockVdeformaJon(mainly(of(l(=(1,(2(modes((Blondin,et,al,2003)( Many(subsequent(2D(studies(obtained(robust(explosions(with(SASI( Foglizzo,et,al,(2006,,2007),, Suwa,et,al,(2010),,, 2D(simulaJon( Takiwaki,et,al,(2013),,, showing(strong( Bruen,et,al,(2013),,etc,, SASI(modes( SASI(in(2V(vs(3D:( But(3D(simulaJons(show( mixed(results.(Whether( SASI(really(leads(to( 3D(simulaJon( explosions(is(sill(unclear.( Average(shock(radius([km]( (((((0.1((((((((((((((((((0.2(((((((((((((((((0.3((((((((((((((((0.4((((( Time(aler(bounce([s]( Hanke,,et,al,,ApJ,(2014), UVa,(April(21st(2015( Shunsaku(Horiuchi((Virginia(Tech)( 14( MeV,transient,detectors, SuperVKamiokande:((+(HyperVK(which(will(be(x20(larger)( • IBD(on(free(protons(yields(~7000(events,(good(energy(info( • ScaPering(on(electrons(yields(~300(events,(good(direcJonal(informaJon( • O16(CC((V>(eV(+(F*)(yields(~100(events( IceCube:(“correlated(noise”( • Each(opJcal(module(has(intrinsic(noise( • Neutrinos(from(a(supernova(is(seen(as(a( SN(at(10(kpc:( rise(in(the(noise(level( Accre+on' • With(5160(modules,(very(wellVsampled( light(curve(can(be(obtained(by(IceCube( Cooling' Time([s]( arXiv:0908.1871,Abbasi,et,al.,(2011), OpJcal(module( UVa,(April(21st(2015( Shunsaku(Horiuchi((Virginia(Tech)( 15( Observing,the,SASI,mechanism, SASI(imprints(fast(variaJons(in(luminosity( and(energy(which(can(be(measured.( ( For(example,(using(the(3D(simulaJon(by( the(Garching(group((Hanke,et,al,2013)(!( ( ( ( ( Tamborra,et,al,(2013),,, see,also,Lund,et,al,(2010,,2012), UVa,(April(21st(2015( Shunsaku(Horiuchi((Virginia(Tech)( 16( Observing,the,SASI,mechanism, SASI(imprints(fast(variaJons(in(luminosity( and(energy(which(can(be(measured.( ( For(example,(using(the(3D(simulaJon(by( the(Garching(group((Hanke,et,al,2013)(!( ( (Great(prospects(to(reveal(characterisJc( (oscillaJons(via(counts(power(spectrum( ( Also,(HyperVK(should(be( able(to(combine(eventV byVevent(reconstrucJon( to(add(an(addiJonal( dimension(to(the( analysis( Tamborra,et,al,(2013),,, see,also,Lund,et,al,(2010,,2012), UVa,(April(21st(2015( Shunsaku(Horiuchi((Virginia(Tech)( 17( Supernova,simula(ons, SophisJcated(simulaJons( • 2D,(3D(with(neutrino(transport( • A(few(progenitor(models( • Address:(explosibility,(neutrino(and(gravitaJonal(wave(signals( Mueller,et,al,(2012,,2013,,2014),,Hanke,et,al,(2013),,Takiwaki,et,al,(2012,,2014),,Bruenn,et,al,(2013,,2014), TwoVdimensional(systemaJc(study( • 2D(with(simplified(neutrino(transport( • ~400(progenitor(models( • Address:(systemaJc(study(of(progenitor(dependence,(SASI,(other( observables( Nakamura,et,al,(2014), OneVdimensional(systemaJc(study( • 1D(with(parameterized(neutrino(heaJng( • Over(100(progenitor(models( • Address:(progenitor(dependence,(black(hole(formaJon( Ugliano,et,al,(2012),,O’Connor,&,O>,(2011,,2013), UVa,(April(21st(2015( Shunsaku(Horiuchi((Virginia(Tech)( 18( 48(solarVmetallicity(models( Systema(c,simula(ons, (10.8(to(75(Msun)( Nakamura,et,al,(2014), UVa,(April(21st(2015( Shunsaku(Horiuchi((Virginia(Tech)(Entropy([kB/baryon]( 19( Importance,of,compactness, "(Define(t400(as(the(Jme(taken(for(the( supernova(shock(to(reach(400(km(( s21( Nakamura,et,al,(2014), #(DistribuJon(of(compactness(in(iniJal(mass( Horiuchi,et,al,(2014),,See,also,Sukhbold,et,al,(2014), UVa,(April(21st(2015( Shunsaku(Horiuchi((Virginia(Tech)( 20( Importance,of,compactness, Nakamura,et,al,2014, UVa,(April(21st(2015( Shunsaku(Horiuchi((Virginia(Tech)( 21( Importance,of,compactness, 2.(Higher(Mdot(!(later(revival( 5.(More(neutrino(!(energeJc(explosion( 1.(Higher(compactness(!(higher(Mdot( 3.(Later(revival(!(more(massive(NS( 4.(More(massive(NS(!(more(neutrinos( 6.(EnergeJc(explosion(!(More(Nickel( Nakamura,et,al,2014, UVa,(April(21st(2015( Shunsaku(Horiuchi((Virginia(Tech)( 22( Measuring,the,compactness, Use(the(fact(that(neutrino(emission(also(depends(on(compactness( 10 IBD(events( 9 PRELIMINARY( 8 7 6 5 4 3 Events at Super-K / 1ms 2 1 0 0 0.2 0.4 0.6 0.8 1 time since first event [sec] O’Connor,&,O>,(2013), Horiuchi,et,al,(in,prep), UVa,(April(21st(2015( Shunsaku(Horiuchi((Virginia(Tech)( 23( SUPERNOVA*NEUTRINOS* -*BEYOND*GALACTIC*EVENTS*-** UVa,(April(21st(2015( Shunsaku(Horiuchi((Virginia(Tech)( 24( Distance,scales,and,physics,outcomes, Nν(>>(1(:(BURST( Nν(~(1(:(MINIVBURST( Nν(<<(1(:(DIFFUSE( ( ( ( SN(rate(~(0.01(/yr( SN(rate(~(0.5(/yr( SN(rate(~(108(/yr( ~kpc( ~Mpc( ~Gpc( Galac+c'burst' Mini7bursts' Diffuse'signal' Physics( Explosion( supernova(variety( Average(emission,(mulJVpopulaJons( reach( mechanism,( with(individual(ID( astronomy( Required( Basics(are( Next(generaJon(( Current(upgrades( detector( covered( UVa,(April(21st(2015( Shunsaku(Horiuchi((Virginia(Tech)( 25( Reach,to,our,neighbors, (M(83((4.5(Mpc)(((((((NGC(6946((5.9(Mpc)( Milky(Way( Andromeda( ~200 ν’s( 1923A,(1945B,(1950B,( 1917A,(1939C,(1948D,( 1957D,(1968L,(1983N( 1968D,(1969P,(1980K,( 2002hh,(2004et,(2008S(
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