the sn – grb - nspersonal.psu.edu/nnp/sn_grb04.pdfmészáros, tata sngrb 04 an explosive...

Mészáros, Tata sngrb 04

TheSN – GRB - NS

Connection

Peter MészárosPennsylvania State University &

Institute for Advanced Study, Princeton


An explosive ancestry… leading to varying degrees of degeneracy :

SN – GRB – NS• Gamma Ray Bursts (GRB)ôBlack hole (BH)

ôSupernova (SN) ô collapsar, …• Magnetars, pulsars (neutron stars: NS), white dwarfs (WD)• And what they lead to…:

→ UHE g, UHE n (ultra-high energy g-ray,neutrinos)→ Ultra-high energy cosmic rays (UHECR) (GZK), → Gravitational Waves (GW) (KHz, mHz, mHz…)→ Electromagnetic (EM) flares : g, X, UV/O, sub-mm, R


Subramanian Chandrasekhar

• Explained WD as compact cores supported by degeneracy pressure of electrons

• Leading the way to later understanding of NS as more massive cores supported by deg.press. of neutrons;

• and understanding of BH , for even larger masses


GRB Sky & Temporal Distrib.

• Cosmological (isotropic) distribut.

• Out to z t 4.5 (20?)• ~ 1/day @ z d few• ~ 1/3 “short” (<2s)→ NS mergers/mag?

• ~ 2/3 “long” (>2s)→ massive coll/SN?


GeV gemission from

GRB, PSR,SNR,

other galactic, extragalactic

&un-id sources• GeV: space obs. (SAS-2, HEAO-A4, Kvant….)• EGRET spark chamber: 5 GRB, 6 PSR & 60 blazars @d10GeV• + ~25 other Unidentified EGRET g-ray sources


SNCommon physical classification:

• Thermonuclear runaway explosion, on accreting WD; progenitor: Mød 10 MŸ

→ Type Ia• Core collapse to NS (or BH)

+envelope ejection; progenitor: Mø t 10 MŸ

→ Type IIType Ib, Ic


Ia

(Cardall ’03)

IbIcII


Core collapse SN

Cardall 03 & U.Tenn


Core-collapse SN bounce, shock &thermal n (10-30 MeV) production

( Cardall 03 & Terascale Supernova Initiative)


SN spectral class:

•Type Ia: opt. brightest at max. light, and : good standard candles !→ supernova project: cosmology,

accel. U, dark energy… SNAP, etc•Type Ib, Ic, II (i.e. core collapse SNe):not very good standard candles…

but : very interesting ..! fl NS, BH..and GRB !

Filipenko 1997

•Type I: absence of H features- Ia: strong Si feature- Ib: no/weak Si, strong He- Ic: no/weak Si, no/weak He

•Type II: obvious H features- IIp: t 2MŸ H-env, H-abs. features- IIL: d 2MŸ H-env, weak H-abs.feat- IIn: no/weak H abs, narrow H emiss

L.C.: a) shock-heated envelopeb) 56Co → 56Fe radioact. tail

SN photometric class:


Mremn.vs.

Møms

• Non-rotating single ms ø

• Mass-loss simplified

• Metallicitydependence?

• Core rotation, binary evol’n?

• etc

(from Heger, et al 03)


Remnant Type vs. Init. Mass & Z

Heger et al aph/0212469

At higher mass,

high metallic flhigh wind massloss ∂ Z1/2 ;stronger afterH-env. is lost

flHe core incr.smaller

flRemnant incr. lessmassive

At low metallic.Mass lossUnimportant,BH boundarydet. by initialStellar mass


Remn. Type & envelope (or lack) fl SN type vs. Init. Mass & Z


Core rot.flCollapsar/Jet SN types

• Assumes

high

core

rotation

•Presence of JET fl collapsar or anisotrop. SN: •Occurs if can assume large core rotation, e.g. from magn instabin single ø, or binary evol, etc•Anisotr. SN: obs.•Evidence from opt pol (few %) (both SN & GRB)•May help also understandanomalies in nucleosy, etc


“Hypernova” fl Anisotropic SNIb/c?

• Nomoto, Woosley, Fryer, Heger et al.: degree of anisotropy (and He core mass) may influence ejected 56Ni mass (hence strength of optical display)

• Viewing angle infleunce observed velocity of ejection (and inferred Eiso )


Remnant type vs. redshift(tentative)

SN Ib/c

SN pair

BH

NS

• Fraction of massive stars leading to various SN and compact remnant types Ø follows from given Z-z dep.

• Implications: at high z, incr.

potential for- UV/X/g

ionizing flux- CRs, n’s, GW- seed accr BH

(→AGNs)- GRB, XR/IR

transients

Heger, Fryer etal, astroph/0212469


NS/MGRNS remnant fivarious outcomes:

• “Normal” B (d1013 G):-Young gamma/radio PSR-ms recycled PSR-Isolated neutron stars (XR,..)-Accreting X-ray pulsar

• “Higher” B (t1013 G)-“Anomalous” X-ray pulsar/AXP-Magnetar: SGR (… GRB ?)fl various interesting effects?

vacuum polariz.,photon splitting…


• Isolated pulsars: ~ 1300 known• Binary radio PSRs: ( many in

GCs,..); of particular interest for Gen.Relat., GW, mass det., etc

• XR surface emission: thermal spectrum – of interest for radius determinatio; not uniform (some pulsation); also a non-thermal PL component, ascribed to magnetospheric emission (more pulsed than thermal); extends down to O/IR

• Binary XRP: ~100, dozens w. cyclotron lines (e.g. XTE); of interest for field measurement. But : bright, Ø not best Chandra, XMM targets; recent advances have been in faint objects

• XMM: detected in binary XRPsXR lines at low energies, ascribed to metals in acc.disk

PSR/XRP


PSR• Radio to gamma emission: • polar or outer gaps?fl GLAST should tell


XRP

Cyclotron lines: XTE (Coburn et al, 02, ApJ 580, 394);

Inferred B compatible with spin up/down obs & young/ middle aged PSR surface fields .. (but..)


Isolated X-ray PSRs• 1E1207: XR lines lines at

0.7, 1.4, 2.1 (coinc. w.instrline), maybe 2.8 keV → ?

• Bignami et al: cyclotron harmonics, indicate lower than usual field?

• Pavlov et al: single PSR, low surf temp and field, so oscill. strenght of higher harm too low to explain harmonics. Could be He in strong field ?(magn. levels quite π unmagn.)

• Several middle aged (10Kyr-Myr) isolated PSR show such lines;


PSR Nebulae & MHD winds• PSR winds: seen by

Chandra in t20 PSR nebulae (t30 at other wavelenghts)

• Crab wind: outer wisps move (also opt)

• › Vela PSR: Chandra measures jet motion, especially interesting faint “outer jet”

Pavlov, GG, Teter, M.A, Kargaltsev, O, Sanwal, D, 2003,ApJ, 591, 1157 "The variable jet of the Vela pulsar"


SGR/MGR sim.(courtesy NASA) • SGRs: leading explanation

is MGR (NS w. Bt1013 G)• AXP: probably not powered

by accretion: No companion seen, and O/IR spectrum does not fit disk Ø may be that AXP ~MGR ?(but: no compelling MGR explanation for O/IR sp)

• Also, two AXPs have now been seen to burst

• SGR X-ray sp. in quiesc is same as AXP, fl AXP ¨SGR

• March 5 SGR: used to have harder quiesc sp than AXPs, recently softened, looks ~ AXP NS/MGR


QED effects on XR polarization modes

Even for B~1012 G, but particularly for BtBQ=m2 c3/ @e = 4.413 x 1013 G, at a critical freq (X/g) where vacuum effects cancel plasma effects Ø the polariz normal modes, as they go through the critical region, retain the same handedness, but change from para to perp (E resp B) ; in old plasma lit. the mode “does not change”, in some new lit. it “does change” identity.

(Ozel, Lai,….Pavlov, Meszaros..):

Mészáros, Tata sngrb 04`

Short(tg d 2 s)

Long(tgt 2 s)

GRB:→ (current paradigm)


“long” GRB from “collapsars”


Collapsar GRB (cont.)


GRB: basic numbers

• Distance: 0.1 d z d4.5 → D ~ 10 28 cm • Fluence: ~10-4 -10-7 erg/cm2

~ 1 ph/cm2

• Energy output: 1053 (Ω/4π) D228.5 F-5 erg

jet: Ω ~ 10-2 – 10-1 → E γ,tot ~ 1051 erg

E γ,tot ~ LΘ x 1010 year ~ Lgal x 1 year• Rate(GRB) ~ 1/day → 10-6(Ω/2π)-1 /yr/gal

(whereas Rate [SN] ~ 107 /yr ~ 1/s at z d1)

∫= dtfluxF .


BH + accr. Torus Jet• Both collapsar or merger → BH+accr.torus→fireball

• Massive rot. ø: sideways pressure confines/channel outflow → fireball Jet

• Nuclear density hot torus→ can have nn→e± jet

• Hot infall →convective dynamo → B~1015 G, twisted (thread BH?)→Alfvénic or e±pγ jet

• (Note: magnetar might do similar)


Explosion FIREBALL• E γ t 1051 Ω-2 D2

28.5 F-5 erg • R0 ~ c t0 ~ 107 t-3 cm

Huge energy in very small volume • τγγ ~ (Eγ/R3

0mec2)σTR0 >> 1 → Fireball: e±,γ,p relativistic gas

• Lγ~Eγ/t0 >> LEdd → expanding (v~c) fireball(Cavallo & Rees, 1978 MN 183:359)

• Observe Eγ> 10 GeV …but γγ→e±, degrade 10 GeV →0.5 MeV? Eγ Et >2(mec2)2/(1-cosΘ)~4(mec2)2/Θ2

Ultrarelativistic flow → Γ t Θ-1 ~ 102

(Fenimore etal 93; Baring & Harding 94)


Jet (outside the star) → shocks• Shocks expected in any

unsteady supersonic outflow (esp. in a non-vacuum environment)

• Internal shocks: fast shells catch up slower shells (unsteady flow)

• External Shock: flow slows down as plows into external medium

• NOTE: “external” and “internal” shocks might be expected also while jet is inside star, as well as after it is outside the star.If inside: gs do not escape (but n can)if outside: gs do escape (and n too)

ò“Internal” shocks

“external” shock →

reverse forward


Non-thermal gs: Internal & External Shocksin optically thin medium outside progenitor:SHORT & LONG-TERM BEHAVIOR

• Lorentz factor Γ first grows Γ∂ r, then coasts Γ∂constant, until …

• Outside the star, after jet is opt. thin: Internal shocks: ri~1012cm→γ-rays (burst, t~sec)

• Externals shocks start at re ~1016cm, progressively weaken as it decelerates

PREDICTION :• External forward shock spectrum

softens in time: X-ray, optical, radio …→long fading afterglow !(t ~ min, hr, day, month)

• External reverse shock (less relativistic):Optical → quick fading ( t ~ mins)(Meszaros & Rees 1997 ApJ 476,232)

Γ

rrc ri re

Shocks solve radiative inefficiency problem (reconvert bulk kin. en. into random en. → radiation)

Int

Ext

Rø


External Forward & Reverse ShockSynchroton & IC spectrum

← Forward shock IC (GeV g )

←Forward shock synchrotron(X,g)

← Reverse shock synchrotron (O)

Meszaros, Rees, Papathanassiou ’94, ApJ 432, 578


GRB 970228 : BeppoSAXDiscovery of an afterglow

• X-ray location:2-3 arcmin →raster

• →optical (arcsec) & radio location

• Can identify host galaxy, redshift

• located atcosmological dist.

NEW ERA!Feb 28 March 3

F_x ~3E-12 erg.cm2/keV/s , decr. By 1/20

(Costa et al 1997, Nature 387:783)


GRB afterglow blast wave model

• Simplest case: adiabatic forward shock synchrotron rad’n from shock-accel. non-thermal e-

• F(n,t) ∂ n-b t -a

• a = (3/2) b• Parameters E0, ee, eB,

(b=(p-1)/2)GRB 970228 as blast wave:

Wijers, Rees & Meszarosl 97 MNRAS 288:L51 fit to

Mészáros, Rees 97 ApJ 476:232 model


Snapshot Afterglow Fits• Simplest case:

tcool(γm)>texp, where N(γ)∂γp for γ>γm (i.e. γc(ool) >γm)

• 3 breaks: na(bs), nm, nc • Fn∂n2 (n5/2) ; n<na ;

∂n1/3 ; na<n<nm ;∂n-(p-1)/2 ; nm<n<nc∂n-p/2 ; n>nc

(Mészáros, Rees & Wijers ’98 ApJ499:301)

Sari, Piran, Narayan ’98 ApJ(Let) 497:L17)

Break frequency decreases in time (at rate dep. on whether ext medium homog. or wind (e.g. r∂r -2 )


Scintillation & Afterglow Limb Brightening

• Radio scintillations:→”sizes” Dr~1016 cm

at distance r~1017 cm• But: equal-arrival timesurfaces are “pears”,edges “younger/bright”→limb-brightening,obs. size < distance

(ÆWaxman 98; Sari 98; Panaitescu-Meszaros 98)

≠ (Granot et al, 99)


GRB Afterglow Radio Detections

GRB970508

Frail, Kulkarni et al 01fireball model & calorimetry

Waxman, Kulkarni, Frail 99:Scintillations → (small) size !


Shock Photon Spectrum• Non-thermal power law

spectrum, both in int. and ext. shocks, due to

• Synchrotron, peak at ~200 keV (or ~ eV?)

• Inv. Compton, peak ~ GeV (or ~200 keV ?

• Sy peak location, ratio Sy/IC dep. on Bsh , ge,m

• Peak softens with time• Ratio Sy/IC decr w. time

E

E2NE

Sy

IC

t

tF

E

E

X,OR g


Fast Opt. Transients: ROTSE

• Robotic Optical Transient Search Experiment (Akerlof, etal, 99, Nat 398, 400)

• Cannon f/1.8 35mm cams coupled to CCD

• fast slew (3s anywhere)• Detected bright, prompt

(15s after trigger) optical flash in GRB990123

• Succesor experiments: ROTSE III, Super-LOTIS, RAPTOR, KAIT, TAROT, NEAT, Faulkes,REM, etc.


Prompt Optical Flashes

• GRB 990123 → bright (9th mag) prompt opt. transient (Akerlof etal 99)

– 1st 10 min: decay steeper than forw. shock • Interpreted as reverse external shock • (predicted : Meszaros&Rees ’97)

• 99-02: Great Desert:Lack of flashes, upper limits mv~12-15

• but: New generation robotic tels: ROTSE III, Super-LOTIS, RAPTOR, KAIT, TAROT, NEAT, Faulkes, REM; etc

• → new prompt optical flashes:GRB 021004, 021211: similar to GRB 990123

• → new “semi- prompt” flashes,( ROTSE IIIa (AU), ROTSE IIIb (TX) ):

GRB 030418, 30723 : π from GRB 990123 !→ t >211, 50 s resp, see forw. shock only?steep rise (ascribed to dusty stell. wind) mR ~ 17 at t~ 30 min, then PL -1.35 decay

(Rykoff etal astro-ph/0310501)

Akerlof etal ’99 ↑

Kulkarni et al ’99 ↑

nFn

n

Sy (rev)

Sy (forw)

0 X,g


Light curve break: Jet Edge Effects

• Monochromatic break in light curve time power law

• expect G∂t-3/8, as long as qlight cone ~G-1 < qjet, (spherical approx is valid)

• “see” jet edge at G ~ qjet-1

• Before edge, Fn∂(r/G)2.In• After edge, Fn∂(rqjet)2.In ,

→ Fn steeper by G2∂t-3/4

• After edge, also side exp. → further steepen Fn∂t-p


Jet Collimation& Energetics

Berger etal 03

• Jet opening angle inv. corr. w. Lg(iso)

• → Lg(corr) ~ const.• GRB030329: evid.

for 2-comp. jet: qg~5o < qradio ~17o

• Etotal = Eg+Ekin~ const.

(→ quasi-standard candle )


Collapsar & SN :does one imply the other ?

• Core collapse of star w. Mt30 MŸ

→ BH + disk (if fast rot.core) → jet (MHD? baryonic? high G,

+ SNR envelope eject (?)• 3D hydro simulations (Newtonian

SR) show that baryonic jet w.high G can be formed/escape

• SNR: not seen numerically yet(but: several previous observational suggestions, e.g. late l.c. hump + reddening- and debate) ;

…… and more recently …

Collapsar & SN (ANIMATION!)

Credit: Derek Fox

& NASA Ø


GRB 030329 ¤ SN 2003dh : Yes !

• Nearest “unequivocal” cosmological GRB: z=0.17

• GRB-SN association: “strong”• Fluence:10-4 erg cm-2 ,

among highest in BATSE,but Dtg~30s, nearby; Eg,iso~1050.5erg: ~typical,

• ESN2003dh,iso ~1052.3 erg ~ ESN1998bw,iso (¨grb980425)

vsn,ej~0.1c (→ “hypernova”)• GRB-SN imultaneous? at most:

d 2 days off-set (from opt. lightcurve)

( ï i.e. not a “supra-nova”)• But: might be 2-stage (<2 day

delay) ø- NS-BH collapse ?→n predictions may test this !


Other GRB-SN• Earliest, most famous & debated

example: (Galama et al, 1998)

GRB980425-SN1998bw(Esn ~1052 erg, but z~0.008, Egrb,iso 1047 erg odd)

• Other possible examples (w/o SN sp.):“red bump” in lightcurve:

GRB980326 (Bloom 99), GRB970228 (Reichart99, Galama 00), GRB000911 (Lazzati 01), GRB991208 (Castro 01), GRB990712 (Sahu00), GRB011211 (Bloom 02), GRB020405 (Price 03)

• Red bump alternative model:dust sublimation or scattering?(Waxman-Draine 00, Esin-Blandford 00)

Possible, but SN spectrum now available in at least two cases

GRB021211 - SN 2002lt

(Dela Valle et al, 2003 AA 406, L33)


END


Fraction of massive stars leading to various SNe & GRB

Heger etal 03

the sn – grb - nspersonal.psu.edu/nnp/sn_grb04.pdfmészáros, tata sngrb 04 an explosive...

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