Cosmological Fast Radio Bursts from Binary White Dwarf Mergers Kunihito Ioka (KEK) Kashiyama, KI & Mészáros 13 ~10年前 GRB Cosmology Massive star origin ⇒ High redshift GRBs Like QSO Like SN Star formation Reionization Metal, Dust ? Dark energy … z~10-30 Larson & Bromm 02 GRB GRBs are useful z~8 for13/11/14 probing high-z Fast Radio Burst by K. Ioka (KEK)QSO, galaxy 2 Radio Dispersion In a plasma, a light signal High energy photon is delayed 2 2 2 2 ! = k c +! p plasma frequency 2 4"ne 4 1 2 1 Low energy photon ! = = 5.63!10 n s" p m Ionized region (2 " ! % " DM % Luminosity !t = 4.15 s $ ' $ ' #1 GHz & #103 pc cm(3 & Distortion in light curve ⇒ DM t~Δt Time 13/11/14 Fast Radio Burst by K. Ioka (KEK)⇒ Reionization History3 Dispersion Measure is the column density of free electrons along light path Dispersion Measure Dispersion Measure ↓ Reionization History Reionization Recombined electrons redshift provide no DM 13/11/14 Redshift Fast Radio Burst by K. Ioka (KEK) KI 03, Inoue 04 4 Intergalactic DM DMIGP including missing baryon 3 -3 DMGalaxy~30-10 pc cm KI 03 13/11/14 Fast Radio Burst by K. Ioka (KEK) 5 DM from Afterglow Distortion at t~Δt ⇒ DM Δt∝ν-2 Unfortunately radio afterglows KI 0313/11/14 Fast Radio Burst by K. Ioka (KEK) are not so bright6 Fast Radio Bursts Thornton+ 13 64m Parkes radio telescope (New South Wales) High Time Resolution Universe (HTRU) Survey High latitude survey (-70 deg < b < -30 deg) ν=1.382 GHz, Δν=400 MHz/1024, Δθ~14 arcmin F=0.6-8.0 Jy ms !!! Most luminous radio transients 13/11/14 Fast Radio Burst by K. Ioka (KEK)if cosmological 7 Dispersion Measure Thornton+ 13 Lorimer Burst δt∝DM・ν-2 Galactic latitude DM=500-1000 cm-3 pc 13/11/14 Fast Radio Burst by K. Ioka (KEK) 8 Summary of FRB Obs. -3 DM=500-1000 cm pc (z=0.5-1, dL~2-6Gpc) 38-40 Sν~Jy ⇒ Eiso~10 erg δt=5.6ms,<4.3,1.4,1.1ms ⇒ cδt(1+z)-1 < 1500(1+z)-1 km Rate~(1±0.5)×104/sky/day~10-3/yr/galaxy ⇔ Supernova rate 10-2/yr/galaxy No repeated bursts so far No counterparts so far 13/11/14 Fast Radio Burst by K. Ioka (KEK) 9 Hassall+ 13 Expected Rate Lorimer+ 13 Trott+ 13 Low frequency component SKA1 could find an extragalactic burst every hour 1 event/hour 13/11/14 Fast Radio Burst by K. Ioka (KEK) 10 Less turbulent Lorimer+ 13 13/11/14 Fast Radio Burst by K. Ioka (KEK) 11 Possible Origins RRAT (Rotating Radio Transient; intermittent pulsar) Giant pulse from a msec/young pulsar Evaporation of BH Rees 77; Blandford 77; Kavic+ 08; Keane+ 12 SN into a nearby star Colgate+ 71,75; Egorov & Postnov 09 Magnetar giant flare Popov & Postnov 07; Thornton+ 13 Collapse of hypermassive NS Falcke & Rezzolla 13; Zhang 13 Binary NS mergers Hansen & Lyutikov 01; Totani 13 Superconducting cosmic strings Cai+ 12 Nearby flaring stars Loeb+ 12 13/11/14 Fast Radio Burst by K. Ioka (KEK) 12 Binary White Dwarf Mergers? Kashiyama, KI & Meszaros 13 Massive WD SN Ia Short GRB via →NS WD pulsar CR e± excess Kashiyama+ 11 GW sources 13/11/14 Fast Radio Burst by K. Ioka (KEK) FRB? 13 Minimum Requirements Energetics Timescale Event rate 13/11/14 Fast Radio Burst by K. Ioka (KEK) 14 Energetics 9 Magnetic Energy Bobs,max~10 G 2 3 B 4!r 43 2 3 E ! " ~ 2 "10 erg B r B 8! 3 9 8.7 WD-WD merger ⇒ Differential rotation ⇒ B GM 2 E ! ! 1050 erg max r v ! " ~ 1 s#1r#3 2 r 8.7 13/11/14 Fast Radio Burst by K. Ioka (KEK) 15 Loren-Aguilar+ 09, Ji+ 13 Timescale WD radius !1 !1 c!t(1+ z) "1.5#108 (1+ z) cm < 108.7cm 1 2 # r"& rcap ! r% ( $ c ' 7 3 2 1 2 ~ 6.7)10 cm r8.7 "0 r cap ~ 2.3 ms r3 2!1 2 c 8.7 0 13/11/14 Fast Radio Burst by K. Ioka (KEK) 16 Event Rate WD-WD merger rate !2 !3 !1 !1 RWD2 ~ 10 !10 yr galaxy ~4000 WDs in SDSS Radial velocity ⇒ Binary fraction & distribution n(a)∝aα Badenes & Maoz 12 13/11/14 Fast Radio Burst by K. Ioka (KEK) 17 Binary White Dwarf Mergers? Kashiyama, KI & Meszaros 13 Energetics 40 EB~10 erg Timescale rcap/c~ms Event rate ~SN Ia SN Ia as a counterpart? 13/11/14 Fast Radio Burst by K. Ioka (KEK) 18 Counterparts Supernova Ia (Double degenerate model) 47 X-ray debris disk LX<10 erg/s for ~100sec Swift for nearby FRBs 19 13/11/14 Fast Radio Burst by K. Loren-Aguilar+Ioka 09, (KEK) recently Beloborodov 13 KI 03 FRB Cosmology McQuinn 13 Reionization Missing baryon Dark energy, cosmological parameters z 3cH0!b (1+ z)dz DMIGP = ' 0 3 1 2 8!Gmp # 1 z % $!m ( + ) +!" & Fast radio bursts c(1+ z) z dz dL = ' 0 3 1 2 as cosmological tools H0 # 1 z % $!m ( + ) +!" & 13/11/14 Fast Radio Burst by K. Ioka (KEK)New frontier? 20 Spin Down Luminosity 2 6 4 B r " 38 1 2 6 4 L ! ~ 1.7#10 erg s$ B r " <<1043 erg/s spin c3 9 8.7 0 B reconnection ⇒ FRB like solar flares, magnetar flares 13/11/14 Fast Radio Burst by K. Ioka (KEK) 21 Acceleration 2 3 B# r 16 2 3 ! " ~ 2.5$10 Volt B # r max 2c2 9 0 8.7 ⇒ e± production ⇒ Coherent radio emission 13/11/14 Fast Radio Burst by K. Ioka (KEK) 22 Beaming Kashiyama, KI & Meszaros 13 Injection ≠ Emission 13/11/14 Fast Radio Burst by K. Ioka (KEK) 23 Brightness Temperature "r2 2! 2 F = ! kT ! d 2 c2 41 "2 T ~ 3!10 K L43remi,10 ⇒ Coherent emission 2 2 P~|E| ~|E1+E2+E3+…+EN| 2 ~N|E1| (incoherent) ~N2|E |2 (coherent) 13/11/14 1 Fast Radio Burst by K. Ioka (KEK) 24 Curvature Radiation 3 3c !c ! " 4#rc 3 "1 ~ 0.72 GHz "3rc,10 1 3 1 3 ! !1100" 9 rc,10 13/11/14 Fast Radio Burst by K. Ioka (KEK) 25 Luminosity 2 Ltot ! (Pc Ncoh )" Npat 4 2 2! e c "17 "1 4 "2 Pc ~ 2 ~ 5!10 erg s !3 rc,10 3rc 4 2 c 16 3 "5 2 Ncoh # ne !Vcoh # ne ! 2 remi ~ ne ! 2 !10 cm !3 rc,10remi,10 ! "c Vemi 1 2 1 28 3 2 Npat # # 4# fremi$remi ~ ! 9 !10 cm fremi,10$remi,7.8 Vcoh Vcoh Vcoh 42 "1 2 "1 "1 4 Ltot ~ 4 !10 erg s fne,7!3 rc,10remi,10"remi,7.8 13/11/14 Fast Radio Burst by K. Ioka (KEK) 26 Electron Density 7 1 2 1 2 1 2 "2 "1 2 ne ~ 2 !10 cm L43!3 rc,10remi,10"remi,7.8 Necessary multiplicity ne ne 3 #1 #1 !GJ = = ~ 8"10 ne,7Bemi,5!0 nGJ Bemi! 2"ce Plasma frequency limit 1 2 $ 2 ' " 4#ne#e ne !c ! ! p " & ) , ne# = 2# % me ( " 7 ,3 5 ,2 27 13/11/14ne * 0.6 +10 cFast Radio Burst by K. Ioka (KEK)m "3 rc,10 Melrose 71 Wilson & Rees 78 Induced Compton Lyubarsky 08 Compton scattering is enhanced by photons To evade the induced Compton 3 14 3 14 3 14 ! ! 2000 rc,10 remi,10ne,7 13/11/14 Fast Radio Burst by K. Ioka (KEK) 28 Summary Fast Radio Burst Thornton+ 13 Dispersion Measure ⇒ Cosmological? KI 03 Binary White Dwarf Merger – Energetics ✔, Timescale ✔, Event Rate ✔ – SN Ia, X-ray debris disk Kashiyama, KI & Mészáros 13 FRB Cosmology Huge occupation # ⇒ BEC? 13/11/14 Fast Radio Burst by K. Ioka (KEK) 29 Thank You Locating Missing Baryon 13/11/14 Fast Radio Burst by K. Ioka (KEK) McQuinn 13 31 Dispersion Measure δt∝DM・ν-2 W∝ν-4 (scattered by turbulence) FRB 110220: α=-2.003±0.006, β=-4.0±0.4 FRB 110703: α=-2.000±0.006 FRB 110627: low S/N FRB 120127: low S/N -3 DM=500-100013/11/14 Fast Radio Burst by K. Ioka (KEK) cm pc 32 250 125 63 Cordes & Lazio 02 31 13/11/14 Fast Radio Burst by K. Ioka (KEK) 33 Cordes & Lazio 02 13/11/14 Fast Radio Burst by K. Ioka (KEK) 34 Host galaxy • Galactic center DM>700 cm-3 pc – W ∝ DbsDos/(Dbs+Dos)2 – If Dbs<<Dos, it locates at the galactic center? • Elliptical host: low DM • Spiral host: DM>700 cm-3 pc if i>87deg (5%) • Intervening galaxies: P<5% 13/11/14 Fast Radio Burst by K. Ioka (KEK) 35 Spectral index is difficult to infer due to position uncertainties 13/11/14 Fast Radio Burst by K. Ioka (KEK) 36 Lorimer Burst 010724 Lorimer+ 07 LMC(Hα, HI) S=30±10Jy, δt<5ms DM=375 cm-3 pc ⇒ z~0.1-0.3 W∝f-4.8±0.4, S∝f-4 13/11/14 b=-41.8degFast Radio Burst by K. Ioka (KEK) 37 Similar Events? J1852-08 (FRB 010621) DM=746 cm-3 pc Keane+ 12 GRB100704A Bannister+ 12 400mJy,13/11/14 7.8ms Fast Radio Burst by K. Ioka (KEK)Rubio-Herrera+ 13 GRB101011A38 Terrestrial? 16 “Perytons” in all 13 telescope receivers Burke-Spolaor+ 11 13/11/14 Fast Radio Burst by K.