Multi-messenger prospects in a gamma-ray world

Multi-messenger prospectsin a gamma-ray world

Valerie Connaughton

Fermi School 2013 University of Delaware, LewesThursday, June 6, 13

Neutrinos are fantastic indicators of proton acceleration

‣ TeV gamma-ray sources are all good candidates

‣ Neutrino detection would confirm hadronic over leptonic models e.g., in blazars. cf. Orphan flares in 1ES 1959+650

‣ characteristics of neutrino --> characteristics of protons

‣ Probe both galactic CRs and identify the source of UHECRs

p + nucleus --> π0, π+, π-

π0 -->ϒϒπ+ or π- --> μ+or μ- νμ

μ+ --> e+ νμ νe

μ- --> e- νe νμ

Similar neutrino production from p-ϒ interactions, via Δ+ resonance

Thursday, June 6, 13

Neutrinos are difficult to detect

ANTARESIceCube


Neutrino detectors have a large background of atmospheric muons and atmospheric neutrinos

ANTARES


Expected neutrino fluxes as a function of energygive hope for > TeV detection from astrophysical sources

Spiering 2012

Low-energyν seen from sun and

SN 1987A


Limits from current neutrino experiments approach Waxman-Bahcall bound


PeV neutrinos have been detected by IceCubeBert and Ernie, origin unknown, but possibly astrophysical


We expect to be able to detect neutrinos from GRBswith IceCube unless the conditions in the GRB are unsuitable


IceCube saw no neutrinos from a collection of 196 GRBsimplying GRBs cannot be the sole source of UHECRs

Abbasi+ 2012


IceCube saw no neutrinos from a collection of 196 GRBsimplying low p content or high bulk Lorentz factor

5

300 350 400 450 500 550 600 650 7005

10

20 region (this result)

3 years IC86

FIG. 4. Constraints on fireball parameters. The shaded re-gion, based on the result of the model-dependent analysis,shows the values of GRB energy in protons and the averagefireball bulk Lorentz factor for modeled fireballs6,9 allowed bythis result at the 90% confidence level. The dotted line in-dicates the values of the parameters to which the completedIceCube detector is expected to be sensitive after 3 years ofdata. The standard values considered9 are shown as dashed-dotted lines and are excluded by this analysis. Note that thequantities shown here are model-dependent.

boost factor �. Increasing � increases the proton en-ergy threshold for pion production in the observer frame,thereby reducing the neutrino flux due to the lower pro-ton density at higher energies. Astrophysical lower limitson � are established by pair production arguments9, butthe upper limit is less clear. Although it is possible that� may take values of up to 1000 in some unusual bursts,the average value is likely lower (usually assumed to bearound 3006,9) and the non-thermal gamma-ray spectrafrom the bursts set a weak constraint that � . 200021.For all considered models, with uniform fixed proton con-tent, very high average values of � are required to becompatible with our limits (Figs. 3, 4).

In the case of models where cosmic rays escape fromthe GRB fireball as neutrons8,10, the neutrons and neu-trinos are created in the same p� interactions, directlyrelating the cosmic ray and neutrino fluxes and remov-ing many uncertainties in the flux calculation. In thesemodels, � also sets the threshold energy for productionof cosmic rays. The requirement that the extragalacticcosmic rays be produced in GRBs therefore does set astrong upper limit on �: increasing it beyond ⇠ 3000causes the proton flux from GRBs to disagree with themeasured cosmic ray flux above 4⇥1018 eV, where extra-galactic cosmic rays are believed to be dominant. Limitson � in neutron-origin models from this analysis (& 2000,Fig. 3) are very close to this point, and as a result allsuch models in which GRBs are responsible for the entireextragalactic cosmic-ray flux are now largely ruled out.

Although the precise constraints are model dependent,

the general conclusion is the same for all the versions offireball phenomenology we have considered here: eitherthe proton density in gamma ray burst fireballs is sub-stantially below the level required to explain the highestenergy cosmic rays or the physics in gamma ray burstshocks is significantly di↵erent from that included in cur-rent models. In either case, our current theories of cos-mic ray and neutrino production in gamma ray burstswill have to be revisited.

1Waxman, E. Cosmological gamma-ray bursts and the highestenergy cosmic rays. Phys. Rev. Lett. 75, 386–389 (1995).

2Vietri, M. The Acceleration of Ultra–High-Energy Cosmic Raysin Gamma-Ray Bursts. Astrophysical Journal 453, 883–889(1995). arXiv:astro-ph/9506081.

3Milgrom, M. & Usov, V. Possible Association of Ultra–High-Energy Cosmic-Ray Events with Strong Gamma-Ray Bursts.Astrophysical Journal Letters 449, L37 (1995). arXiv:astro-ph/9505009.

4Waxman, E. & Bahcall, J. High energy neutrinos from cosmolog-ical gamma-ray burst fireballs. Phys. Rev. Lett. 78, 2292–2295(1997).

5Avrorin, A. V. et al. Search for neutrinos from gamma-ray burstswith the Baikal neutrino telescope NT200. Astronomy Letters37, 692–698 (2011).

6Abbasi, R. et al. Search for Muon Neutrinos from Gamma-rayBursts with the IceCube Neutrino Telescope. Astrophysical Jour-nal 710, 346–359 (2010).

7Abbasi, R. et al. Limits on Neutrino Emission from Gamma-RayBursts with the 40 String IceCube Detector. Phys. Rev. Lett.106, 141101 (2011). 1101.1448.

8Rachen, J. P. & Meszaros, P. Cosmic rays and neutrinosfrom gamma-ray bursts. In C. A. Meegan, R. D. Preece, &T. M. Koshut (ed.) Gamma-Ray Bursts, 4th Hunstville Sym-posium, vol. 428 of American Institute of Physics ConferenceSeries, 776–780 (1998). arXiv:astro-ph/9811266.

9Guetta, D., Hooper, D., Alvarez-Muniz, J., Halzen, F. &Reuveni, E. Neutrinos from individual gamma-ray bursts in theBATSE catalog. Astroparticle Physics 20, 429–455 (2004).

10Ahlers, M., Gonzalez-Garcia, M. C. & Halzen, F. GRBs on pro-bation: Testing the UHE CR paradigm with IceCube. Astropar-ticle Physics 35, 87–94 (2011). 1103.3421.

11Becker, J. K. High-energy neutrinos in the context of multi-messenger astrophysics. Physics Reports 458, 173–246 (2008).0710.1557.

12Abbasi, R. et al. The IceCube data acquisition system: Sig-nal capture, digitization, and timestamping. Nuclear Instru-ments and Methods in Physics Research A 601, 294–316 (2009).0810.4930.

13Ahrens, J. et al. Muon track reconstruction and data selectiontechniques in AMANDA. Nucl. Instrum. and Meth. A 524, 169–194 (2004).

14GRB Coordinates Network. http://gcn.gsfc.nasa.gov.15Becker, J. K., Stamatikos, M., Halzen, F. & Rhode, W. Coinci-dent GRB neutrino flux predictions: Implications for experimen-tal UHE neutrino physics. Astroparticle Physics 25, 118–128(2006). arXiv:astro-ph/0511785.

16Waxman, E. Astrophysical sources of high energy neutrinos.Nucl. Phys. B Proc. Suppl. 118, 353–362 (2003).

17Feldman, G. J. & Cousins, R. D. Unified approach to the classicalstatistical analysis of small signals. Physical Review D 57, 3873–3889 (1998).

18Guetta, D., Spada, M. & Waxman, E. On the Neutrino Fluxfrom Gamma-Ray Bursts. Astrophysical Journal 559, 101–109(2001).

19Baerwald, P., Hummer, S. & Winter, W. Systematics in Ag-gregated Neutrino Fluxes and Flavor Ratios from Gamma-RayBursts. Astroparticle Physics 35, 508 – 529 (2012). 1107.5583.

Abbasi+ 2012


Limits from individual GRBs: non-detection of GRB 130427A

‣ Is this really a good GRB candidate? 100 GeV photons --> high 𝛤

Gao, Kashiyama & Meszaros 2013


Is there a distribution of Bulk Lorentz factors in GRBs?This might be a way to explain LAT non-detectionsand give hope to the neutrino community!

0 1 2 3 4 5Redshift

0

200

400

600

800

1000

1200

1400Γ

(γma

x = 10

0 MeV

, tva

r = 0.

1s)

090902B

090510

080916C

091127

090926A

Γmin

xΓma

LAT DetectionsSpectral Cutoffs

LAT Non-detectionsΓγγ

0

Ackermann+ 2011


Future of high-energy neutrino detection

‣ IceCube is concentrating on its low-energy supplement DeepCore

‣ Km3NeT is a new water-based km3 array


Gravitational wave detection is expected from General Relativity from sources such as merger GRBs

Inspiral signal enters sensitive band (> 50 Hz) about 50 s before coalescence.


Gravitational Waves are difficult to detect


Gravitational Wave detectors have a strong background that limits their sensitive frequency range

from hermes.aei.mpg.deThursday, June 6, 13

Gravitational waves have not been detected in a study of 154 GRBs with data from at least 2 GW stations (26 short GRBs)

Abadie+ 2012


Advanced LIGO will be much more sensitive and will begin to come online (with A-Virgo and others) in 2016


We expect good overlap between GBM-detected short GRBsand gravitational wave candidates from Advanced LIGO/Virgo

Pelassa+ 2012


GW detectors have crude localizationsGW trigger• Simulated early aLIGO-aVirgo

event near threshold

• SNR 8.7 (H1), 7.2 (L1), 3.1 (V1)

• localization from Bayesian parameter estimation (quite slow, but optimal)

• 1σ: 30 deg2 2σ: 180 deg2

• Also time (ms), component masses (NS vs BH), etc.

• First detections likely to be at threshold (100 deg2, etc)

• However routine detection also implies there will be a few strong events well above threshold

Sunday, March 24, 13


Search GW data

Localization of GW-GRB

Simultaneous GW Trigger + Swift

short GRB

XRT localization

Optical Counterpart

Simultaneous GW Trigger + GBM

short GRBXRT Tiling XRT

localizationOptical

Counterpart

GW TriggerNo γ-ray XRT Tiling XRT

localizationOptical

CounterpartSpectrum

Spectrum

Spectrum

GRB Trigger

XRT Tiling XRT localization

Optical Counterpart

Spectrum

From Judy RacusinThursday, June 6, 13

There is a danger that a GW will be seen and nobody willbelieve it because nobody else can look!

Keep Swift & Fermi in operation in the A-LIGO era!Encourage follow-up of GBM error boxes for short GRBs.

CTA in survey mode might get the best localization for follow-up of a short GRB seen in GW!

TeV astrophysics, too, used to be an exotic field viewed skeptically by real astronomers.


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Multi-messenger prospects in a gamma-ray world