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Search for Neutrino Emission from Fast Radio Bursts with IceCube Donglian Xu Samuel Fahey, Justin Vandenbroucke and Ali Kheirandish for the IceCube Collaboration TeV Particle Astrophysics (TeVPA) 2017 August 7 - 11, 2017 | Columbus, Ohio Fast Radio Bursts - Discovery in 2007 2 e2 Lorimer et al.,Science 318 (5851): 777-780 2 ∆tdelay = 3 DM w− 2⇡mec · · 24 2 =1.5 10− s DM w− ⇥ · · 3 DM = n dl = 375 1cm− pc e ± Z “very compact” SMC J0045−7042 (70) J0111−7131 (76) J0113−7220 (125) “extragalactic”? J0045−7319 (105) J0131−7310 (205) Figure 2: Frequency evolution and integrated pulse shape of!the radio burst.4 The.8 survey0.4 data, collected on 2001δ Augusttwidth 24, are=4 shown. here6 ms as a two-dimensio ( nal ‘waterfall)− plot’± of intensity as a function of radio frequency versus time. The dispersion1.4GHzis clearly seen as a quadratic sweep across the frequency band, with broadening towards lower frequencies. From a measurement of the pulse delay across the receiver band using standard pulsar timing techniques, we determine the DM to be 375 dtI1 cm−3!pc. The two150 white lines50Jy separated byms 15 ms @ that 1 bound.4 GHz the pulse show the expected behavior± for the' cold-plasma dispersion± law assuming a DM of 375 cm−3 pc. The horizontal line at 1.34 GHz is an artifact in the data caused by a malfunctioning frequency Z ∼ channel. This plot is for one of the offset beams in which the digitizers were not saturated. By splitting the data into four frequency sub-bands we have measured both the half-power Galactic DM: pulse width• andA fluxtotal density spectrumof ~ over23 the observingFRBs bandwidth. detected Accounting for pulse to date. 3 broadening due to known instrumental effects, we determine afrequencyscalingrelationship 25cm− pc for the observed width W =4.6ms(f/1.4GHz)−4.8±0.4,wheref is the observing frequency. Apower-lawfittothemeanfluxdensitiesobtainedineachsub-Estimated FRB eventband yieldsrate a spectral is index ~1,000/day of 4 1.Inset:thetotal-powersignalafteradispersivedelaycorrection assuming a DM of 375 cm− −±3 pc and a reference frequency of 1.5165 GHz. The time axis on theinnerfigurealsospans the range 0–500 ms. Figure 1: Multi-wavelength image of the field surrounding theburst.Thegrayscaleand Donglian Xu | High-E Neutrinos12 from Fast Radio Bursts | TeVPA2017, Columbus contours respectively show Hα and HI emission associated with the SMC (8, 9). Crosses mark the positions of the five known radio pulsars in the SMC and are annotated with their names and DMs in parentheses in units of cm−3 pc. The open circles show the positions of each of the 13 beams in the survey pointing of diameter equal to the half-power width. The strongest detection saturated the single-bit digitizers in the data acquisitionsystem,indicatingthatitsS/N 23. Its location is marked with a square at right ascension 01h 18m 06s and declination 75≫◦ 12′ ′′ − 19 (J2000 coordinates). The other two detections (with S/Ns of 14 and 21) are marked with smaller circles. The saturation makes the true position difficult to localize accurately. Based on the half-power width of the multibeam system, the positional uncertainty is nominally 7′. However, the true position is probably slightly ( few arcmin) north-west of this position given± the non-detection of the burst in the other beams.∼ 11 Fast Radio Bursts Emitting Neutrinos? 3 • Blitzar “Cataclysmic” [H. Falcke and L. Rezzolla, A&A 562, A137 (2014)] • Binary neutron star merger [T. Totani, Pub. Astron. Soc. Jpn. 65, L12 (2013)] • Evaporating primordial black holes [Halzen et al., PRD 1995] “MeV neutrinos” • Magnetar/SGRs hyperflares [S. B. Popov and K. A. Postnov, arXiv:1307.4924] [Halzen et al. (2005) astro-ph/0503348] “TeV neutrinos”? this work Donglian Xu | High-E Neutrinos from Fast Radio Bursts | TeVPA2017, Columbus Goal: detecting TeV-PeV astrophysical neutrinos Construction completed in December 2010 IceCube Detector 4 Donglian Xu | High-E Neutrinos from Fast Radio Bursts | Jan. 29, 2017 MartinMartin Rongen Rongen LakeLake Baikal Baikal 5 Martin Rongen Neutrino Signatures in IceCube SeptemberSeptember 2016 2016 EventEvent signaturessignatures Lake Baikal Event signatures September 2016 (1) Track: charged current νμ ChargedCharged current current νμ ν Charged current ν • <1o Angular resolution μ μ ● ● Factor ~2 energy resolution ●FactorFactor ~2 ~2 energy energy resolution resolution Factor ~ 2 energy ● <1° angular resolution • ● <1° angular resolution resolution ● <1° angular resolution data 2013 Neutral current, Charged current νe (2) Cascade / Shower: all Neutral current, Charged current ν ● 15% resolution on the Neutral current, Charged currente ν deposited energy neutral current, charged e ● 15% resolution on the ● ● 10° angular resolution current νe, low-E charged deposited15% resolution energy on the (above 100 TeV) deposited energy current ντ ● 10° angular resolution ● (above10° angular 100 TeV) resolution Double Bang ν • 10o Angular resolution (above 100 TeV) τ above100 TeV data ● Vertex seperation ~50m/PeV ● Not yet observed Double Bang ντ • 15% energy resolution on “high degeneracy”Double Bang ν τ 4 deposited energy ● Vertex seperation ~50m/PeV ● Vertex seperation ~50m/PeV IceCube has detected a diffuse astrophysical● Not yet neutrinoobserved flux, but no TeV neutrino point sources have● beenNot yet observedidentified to date. 4 Donglian Xu | High-E Neutrinos from Fast Radio Bursts | TeVPA2017, Columbus 4 All Sky Fast Radio Bursts with IceCube Coverage 6 • Burst times cover IceCube data taking seasons from 2010 to 2015 (6 years) • A total of 29 FRBs (11 unique locations). Repeated bursts are treated as unique bursts in space & time FRB121102 repeated 26 times (17 times within our data sample) North South Donglian Xu | High-E Neutrinos from Fast Radio Bursts | TeVPA2017, Columbus Event Samples & Background Modeling 7 Background PDF derived from North South off-time data (DEC >= -5o) (DEC < -5o) 842,597 events 379,261 events (collected from (collected from 2011-2015) 2010-2014) dominated by dominated by atmospheric atmospheric neutrinos muons A total of 1.2 million events in 6 years 2015 ApJ 805 L5 ApJ 845 (2017), 1, 14 Donglian Xu | High-E Neutrinos from Fast Radio Bursts | TeVPA2017, Columbus Analysis Method: Unbinned Maximum Likelihood 8 The likelihood for observing N events with properties x i for ( n s + n b ) { } expected number of events is: (n + n )N N L(N, x ; n + n )= s b exp( (n + n )) P (x ) { i} s b N! · − s b · i i=1 Y The normalized probability of observing event i is P ( x i ) : nsS(xi)+nbB(xi) Si = Stime(ti) Sspace(~xi) P (xi)= · ns + nb B = B (t ) B (~x ) i time i · space i “temporal” + “spatial” L(N, x ; n + n ) T := ln { i} s b L0(N, xi ; nb) N nˆ S { } T := nˆ + ln(1 + s i ) − s <n >B i=1 b i X Donglian Xu | High-E Neutrinos from Fast Radio Bursts | TeVPA2017, Columbus Search Strategy 9 • Stacking “Distributed fluence test” Source 1 Source 2 Source 3 STACKING declination r.a • Max-burst ‣ Model independent “Single bright neutrino source test” ‣ Expanding time windows Source 3 centered at burst times Source 1 Source 2 ‣ 25 time windows from 10 ms to 2 days, expanding as i declination 2 x10 ms (i =0, …, 24) r.a Donglian Xu | High-E Neutrinos from Fast Radio Bursts | TeVPA2017, Columbus Sensitivity & Discovery Potentials - Stacking 10 North South 2 2 2 2 E− sensitivity E− 5σ disc. poten. E− sensitivity E− 5σ disc. poten. 2.5 2.5 2.5 2.5 E− sensitivity E− 5σ disc. poten. E− sensitivity E− 5σ disc. poten. 3 3 3 3 E− sensitivity E− 5σ disc. poten. E− sensitivity E− 5σ disc. poten. ) ) IceCube Preliminary 2 2 − IceCube Preliminary − 100 1 10− 2 10 1 − 10− F @ 100 TeV (GeV cm 2 F @ 100 TeV (GeV cm 2 E E 2 1 0 1 2 3 4 5 2 1 0 1 2 3 4 5 10− 10− 10 10 10 10 10 10 10− 10− 10 10 10 10 10 10 ∆ T(s) ∆T(s) ‣25 time windows from 10 ms to 2 days, expanding as 2ix10 ms (i =0, …, 24) ‣One coincident event can be discovery in the short time windows Donglian Xu | High-E Neutrinos from Fast Radio Bursts | TeVPA2017, Columbus Sensitivity & Discovery Potentials - Max-burst 11 North South 2 2 2 2 E− sensitivity E− 5σ disc. poten. E− sensitivity E− 5σ disc. poten. 2.5 2.5 2.5 2.5 E− sensitivity E− 5σ disc. poten. E− sensitivity E− 5σ disc. poten. 3 3 3 3 E− sensitivity E− 5σ disc. poten. E− sensitivity E− 5σ disc. poten. IceCube Preliminary ) ) 2 2 − − IceCube Preliminary 1 10− 100 2 10− F @ 100 TeV (GeV cm 2 F @ 100 TeV (GeV cm E 2 E 1 10− 2 1 0 1 2 3 4 5 2 1 0 1 2 3 4 5 10− 10− 10 10 10 10 10 10 10− 10− 10 10 10 10 10 10 ∆ T(s) ∆T(s) ‣25 time windows from 10 ms to 2 days, expanding as 2ix10 ms (i =0, …, 24) ‣One coincident event can be discovery in the short time windows Donglian Xu | High-E Neutrinos from Fast Radio Bursts | TeVPA2017, Columbus Results - Most Significant Bursts & Events 12 North Max-burst South Max-burst Most significant time window: Most significant time window: ∆T = 655.36 s ∆T = 167772.16 s Donglian Xu | High-E Neutrinos from Fast Radio Bursts | TeVPA2017, Columbus Results - Upper Limits 13 North Stacking North Max-burst 2 2 2 2 E− sensitivity E− upper limit E− sensitivity E− upper limit 2.5 2.5 2.5 2.5 E− sensitivity E− upper limit E− sensitivity E− upper limit 3 3 3 3 E− sensitivity E− upper limit E− sensitivity E− upper limit ) IceCube Preliminary ) IceCube Preliminary 2 2 − ∆T = 655.36 s − ∆T = 655.36 s 1 10 1 10− − 2 2 10− 10− F @ 100 TeV (GeV cm F @ 100 TeV (GeV cm 2 2 E E 2 1 0 1 2 3 4 5 2 1 0 1 2 3 4 5 10− 10− 10 10 10 10 10 10 10− 10− 10 10 10 10 10 10 ∆ T(s) ∆ T(s) Donglian Xu | High-E Neutrinos from Fast Radio Bursts | TeVPA2017, Columbus Results - Upper Limits 14 South Stacking South Max-burst 2 2 2 2 E− sensitivity E− upper limit E− sensitivity E− upper limit 2.5 2.5 2.5 2.5 E− sensitivity E− upper limit E− sensitivity E− upper limit 3 3 3 3 E− sensitivity E− upper limit E− sensitivity E− upper limit ) ) IceCube Preliminary 2 0 IceCube Preliminary 2 10 − − 1 10− F @ 100 TeV (GeV cm F @ 100 TeV (GeV cm 2 2 E E 1 10− 2 10− 2 1 0 1 2 3 4 5 10 2 10 1 100 101 102 103 104 105 10− 10− 10 10 10 10 10 10 − − ∆ ∆T(s) T(s) Donglian Xu | High-E Neutrinos from Fast Radio Bursts | TeVPA2017, Columbus 2 crete sources has been found, either in searches for clus- tiple muons produced in the same extensive air shower).
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  • Neutron Star Collapse Times, Gamma-Ray Bursts and Fast Radio Bursts

    Neutron Star Collapse Times, Gamma-Ray Bursts and Fast Radio Bursts

    MNRAS 441, 2433–2439 (2014) doi:10.1093/mnras/stu720 The birth of black holes: neutron star collapse times, gamma-ray bursts and fast radio bursts ‹ Vikram Ravi1,2 and Paul D. Lasky1 Downloaded from https://academic.oup.com/mnras/article-abstract/441/3/2433/1126394 by California Institute of Technology user on 24 June 2019 1School of Physics, University of Melbourne, Parkville, VIC 3010, Australia 2CSIRO Astronomy and Space Science, Australia Telescope National Facility, PO Box 76, Epping, NSW 1710, Australia Accepted 2014 April 8. Received 2014 April 7; in original form 2013 November 29 ABSTRACT Recent observations of short gamma-ray bursts (SGRBs) suggest that binary neutron star (NS) mergers can create highly magnetized, millisecond NSs. Sharp cut-offs in X-ray afterglow plateaus of some SGRBs hint at the gravitational collapse of these remnant NSs to black holes. The collapse of such ‘supramassive’ NSs also describes the blitzar model, a leading candidate for the progenitors of fast radio bursts (FRBs). The observation of an FRB associated with an SGRB would provide compelling evidence for the blitzar model and the binary NS merger scenario of SGRBs, and lead to interesting constraints on the NS equation of state. We predict the collapse times of supramassive NSs created in binary NS mergers, finding that such stars collapse ∼10–4.4 × 104 s (95 per cent confidence) after the merger. This directly impacts observations targeting NS remnants of binary NS mergers, providing the optimal window for high time resolution radio and X-ray follow-up of SGRBs and gravitational wave bursts.