Gamma-Ray-Bursts in Gamma-Ray-Bursts in Nuclear AstrophysicsNuclear Astrophysics

Giuseppe PagliaraGiuseppe Pagliara

Dip. Fisica Politecnico di TorinoDip. Fisica Politecnico di Torino

INFN-FerraraINFN-Ferrara

XI Convegno su Problemi di Fisica Nucleare XI Convegno su Problemi di Fisica Nucleare Teorica - Cortona 2006Teorica - Cortona 2006

General features of GRBs General features of GRBs

Duration 0.01-1000sDuration 0.01-1000s ~ 1 burst per day ~ 1 burst per day

(BATSE)(BATSE) Isotropic distribution Isotropic distribution -

rate of ~2 Gpcrate of ~2 Gpc-3-3 yr yr-1 -1

~100keV photons~100keV photons Cosmological Origin Cosmological Origin The brightness of a The brightness of a

GRB, GRB, E~10E~105511ergs ergs (beaming effect),(beaming effect), is is comparable to the comparable to the brightness of the rest of brightness of the rest of

the Universe combinedthe Universe combined..

Very complex time-Very complex time-structurestructure

““Two kinds of precursors”Two kinds of precursors”

SN-GRB connection, time delays from second

to years

Prompt-emission precursor, few

hundred of seconds

Rotating massive stars, whose central Rotating massive stars, whose central

region collapses to a black hole region collapses to a black hole surrounded by an accretion disk. surrounded by an accretion disk.

Outflows are collimated by passing Outflows are collimated by passing through the stellar mantle. through the stellar mantle.

Detailed numerical analysis of jet Detailed numerical analysis of jet formation.formation.

Fits naturally in a general scheme Fits naturally in a general scheme describing collapse of massive stars.describing collapse of massive stars.

- Large angular momentum needed, - Large angular momentum needed, difficult to achieve.difficult to achieve.

SN – GRB time delay: less then SN – GRB time delay: less then 100 s.100 s.

Can it explain long time delay precursors ?Can it explain long time delay precursors ?

The Collapsar modelThe Collapsar model

The Quark-Deconfinement Nova modelThe Quark-Deconfinement Nova model

I.M. Lifshitz and Y. Kagan, Sov. Phys. JETP 35 (1972) 206I.M. Lifshitz and Y. Kagan, Sov. Phys. JETP 35 (1972) 206

K. Iida and K. Sato, Phys. Rev. C58 (1998) 2538K. Iida and K. Sato, Phys. Rev. C58 (1998) 2538

I.M. Lifshitz and Y. Kagan, Sov. Phys. JETP 35 (1972) 206I.M. Lifshitz and Y. Kagan, Sov. Phys. JETP 35 (1972) 206

K. Iida and K. Sato, Phys. Rev. C58 (1998) 2538K. Iida and K. Sato, Phys. Rev. C58 (1998) 2538

Droplet potential energy:Droplet potential energy:Droplet potential energy:Droplet potential energy:

2323** 4

3

4)( RaRaRRnRU sVHQQ

nnQ*Q* baryonic number density baryonic number density

in the Q*-phase at a in the Q*-phase at a fixed pressure P.fixed pressure P.

μμQ*Q*,,μμHH chemical potentialschemical potentials

at a fixed pressure P.at a fixed pressure P.

σσ surface tension surface tension (=10,30 MeV/fm(=10,30 MeV/fm22))

nnQ*Q* baryonic number density baryonic number density

in the Q*-phase at a in the Q*-phase at a fixed pressure P.fixed pressure P.

μμQ*Q*,,μμHH chemical potentialschemical potentials

at a fixed pressure P.at a fixed pressure P.

σσ surface tension surface tension (=10,30 MeV/fm(=10,30 MeV/fm22))

Quantum nucleation theoryQuantum nucleation theory

Delayed formation of quark Delayed formation of quark matter in Compact Starsmatter in Compact Stars

Quark matter cannot appear before the Quark matter cannot appear before the PNS has deleptonized (Pons et al 2001)PNS has deleptonized (Pons et al 2001)

Quark droplet nucleation timeQuark droplet nucleation time“mass filtering”“mass filtering”

Critical mass for = 0 B1/4 = 170 MeV

Mass accretion

Critical mass for= 30 MeV/fm2

B1/4 = 170 MeV

Age of the Universe!

Two families of CSsTwo families of CSs

Conversion from HS Conversion from HS to HyS (QS) with the to HyS (QS) with the same Msame MBB

The reaction that generates gamma-ray is:The reaction that generates gamma-ray is:

The efficency of this reaction in a strong gravitational field is:The efficency of this reaction in a strong gravitational field is:

[J. D. Salmonson and J. R. Wilson, ApJ 545 (1999) 859][J. D. Salmonson and J. R. Wilson, ApJ 545 (1999) 859]

The reaction that generates gamma-ray is:The reaction that generates gamma-ray is:

The efficency of this reaction in a strong gravitational field is:The efficency of this reaction in a strong gravitational field is:

[J. D. Salmonson and J. R. Wilson, ApJ 545 (1999) 859][J. D. Salmonson and J. R. Wilson, ApJ 545 (1999) 859]

How to generate GRBsHow to generate GRBs

2 ee

%10

The energy released (in the The energy released (in the strong deflagration see Parenti talkstrong deflagration see Parenti talk) ) is carried out by neutrinos and antineutrinos.is carried out by neutrinos and antineutrinos.The energy released (in the The energy released (in the strong deflagration see Parenti talkstrong deflagration see Parenti talk) ) is carried out by neutrinos and antineutrinos.is carried out by neutrinos and antineutrinos.

ergEE conv5251 1010

Hadronic Stars Hadronic Stars Hybrid or Quark Stars Hybrid or Quark StarsZ.Berezhiani, I.Bombaci, A.D., F.Frontera, A.Lavagno, ApJ586(2003)1250Z.Berezhiani, I.Bombaci, A.D., F.Frontera, A.Lavagno, ApJ586(2003)1250

Drago, Lavagno Pagliara 2004, Bombaci Parenti Vidana 2004…Drago, Lavagno Pagliara 2004, Bombaci Parenti Vidana 2004…

Metastability due to delayed production of Quark Matter .Metastability due to delayed production of Quark Matter .

1) conversion to Quark Matter (it is NOT a detonation (see Parenti ))1) conversion to Quark Matter (it is NOT a detonation (see Parenti ))

2) cooling (neutrino emission) 2) cooling (neutrino emission)

3) neutrino – antineutrino annihilation 3) neutrino – antineutrino annihilation

4)(possible) beaming due to strong magnetic field and star rotation4)(possible) beaming due to strong magnetic field and star rotation

++ Fits naturally into a scheme describing QM production. Fits naturally into a scheme describing QM production.

Energy and duration of the GRB are OK.Energy and duration of the GRB are OK.

- - No calculation of beam formation, yet.No calculation of beam formation, yet.

SN – GRB time delay: minutes SN – GRB time delay: minutes years years

depending on mass accretion ratedepending on mass accretion rate

Temporal structure of Temporal structure of GRBsGRBs

… … back to the databack to the data

ANALYSIS of the distribution of peaks intervalsANALYSIS of the distribution of peaks intervals

Drago & Pagliara Drago & Pagliara 20052005

Excluding QTs

Deviation from lognorm & power law tail (slope = -1.2)

Probability to find more than 2 QT in the same burst

Analysis on 36 bursts having long QT (red dots): the subsample is not Analysis on 36 bursts having long QT (red dots): the subsample is not anomalousanomalous

Analysis of PreQE and PostQEAnalysis of PreQE and PostQE

Same “variability”: the same emission mechanism, Same “variability”: the same emission mechanism, internal shocks internal shocks

Same dispersions but Same dispersions but different average durationdifferent average duration

PreQE: PreQE: 20s20s

PostQE:PostQE:~40s~40s

QTs:~ 80s QTs:~ 80s

Three characterisitc Three characterisitc time scalestime scales

No evidence of a continuous No evidence of a continuous time dilationtime dilation

Interpretation:Interpretation:

1)Wind modulation 1)Wind modulation model: during QTs no model: during QTs no collisions between the collisions between the emitted shellsemitted shells

2) Dormant inner engine 2) Dormant inner engine during the long QTs during the long QTs

Huge energy Huge energy requirementsrequirements

No explanation for No explanation for the different time the different time scalesscales

It is likely for short It is likely for short QTQT

Reduced energy Reduced energy emissionemission

Possible explanation Possible explanation of the different time of the different time scales in the Quark scales in the Quark deconfinement model deconfinement model

It is likely for long QTIt is likely for long QT

Quiescent times in very long Quiescent times in very long GRBsGRBs

High red-shiftHigh red-shift

… … back to the theoryback to the theoryIn the first version of the Quark In the first version of the Quark

deconfinement model only the MIT bag EOS deconfinement model only the MIT bag EOS was consideredwas considered

……butbut

in the last 8 years, the study of the QCD phase diagram in the last 8 years, the study of the QCD phase diagram revealed the possible existence of Color revealed the possible existence of Color

Superconductivity at “small” temperature and large Superconductivity at “small” temperature and large densitydensity

More refined calculationsMore refined calculations

Two first order phase transitions:

Hadronic matter Unpaired Quark Matter(2SC) CFL

CFL cannot appear until CFL cannot appear until the star has deleptonizedthe star has deleptonized

Ruster et al hep-ph/0509073Ruster et al hep-ph/0509073

Double GRBs generated by double phase Double GRBs generated by double phase transitionstransitions

Two steps (same barionic mass):Two steps (same barionic mass):

1)1) transition from hadronic matter to transition from hadronic matter to unpaired or 2SC quark matter. unpaired or 2SC quark matter. “Mass filtering”“Mass filtering”

2) The mass of the star is now fixed. 2) The mass of the star is now fixed. After strangeness production, After strangeness production, transition from 2SC to CFL quark transition from 2SC to CFL quark matter. Decay time scale matter. Decay time scale ττ few tens few tens of second of second

Nucleation time of CFL phaseNucleation time of CFL phase

Energy releasedEnergy released

Energy of the second transition larger than the first Energy of the second transition larger than the first transition due to the large CFL gap (100 MeV)transition due to the large CFL gap (100 MeV)

Bombaci, Lugones, Vidana Bombaci, Lugones, Vidana 20062006

Drago, Lavagno, Pagliara Drago, Lavagno, Pagliara 20042004

… … a very recent M-R a very recent M-R analysisanalysis

Color superconductivity (and other Color superconductivity (and other effects ) must be included in the quark effects ) must be included in the quark

EOSs !!EOSs !!

Are LGRBs Are LGRBs signals of the signals of the

successive successive reassesments of reassesments of Compact stars?Compact stars?

Low density: Hyperons - Kaon condensates…Low density: Hyperons - Kaon condensates…

ConclusionsConclusions• A “standard model” the A “standard model” the

Collapsar modelCollapsar model• One of the alternative model: One of the alternative model:

the quark deconfinement modelthe quark deconfinement model• Possibility to connect GRBs and Possibility to connect GRBs and

the properties of strongly the properties of strongly interacting matter! interacting matter!

Collaborators: Alessandro Drago, Università Ferrara

Andrea Lavagno, Dip. Fisica Politecnico di Torino

APPENDICI

Other possible signaturesOther possible signatures

For a single Poisson processFor a single Poisson process

Variable ratesVariable rates

SOLAR FLARESSOLAR FLARES

Power law distribution for Solar flares Power law distribution for Solar flares waiting times (waiting times (Wheatland APJ 2000Wheatland APJ 2000))

The initial masses of The initial masses of the compact stars are the compact stars are distributed near Mdistributed near Mcrit, crit,

different central desity different central desity and nucleation times and nucleation times

of the CFL phase f(of the CFL phase f((M))(M))

Could explain Could explain the power law the power law

tail of long tail of long QTs ?QTs ?

Origin of power law:Origin of power law:

Probability of tunneling