sign in sign up
<<
Home , ANTARES (telescope)

Astrophysics and Astronomy

Madhurima Pandey and Cosmology Division Saha Institute of Nuclear Physics, HBNI, Kolkata

WHEPP XVI, IIT Guwahati

Wednesday, December 4, 2019 WHEPP XVI 1 Wednesday, December 4, 2019 WHEPP XVI 2

Wednesday, December 4, 2019 WHEPP XVI 3 Solar Neutrino  Neutrino and antineutrino production mechanism [1]

 Rates proportional to , and - depend on specific processes, and - effective coupling constants for vector and axial – vector interaction.  Antineutrinos can be probed at the detector in KeV energy range.

[1] E. Vitagliano et al., JCAP 12, 010 (2017)

Wednesday, December 4, 2019 WHEPP XVI 4 Solar Neutrino

 sterile in KeV range - 1. capture on a stable isotope of dysprosium if > 2.83 KeV [2] 2. slightly heavier sterile neutrinos include unstable isotopes[3] coherent inelastic scattering on atoms [4] and electron scattering [5]  CP violation

 MSW effect

[2] T. Lasserre et al., arXiv:1609.04671, [3] Y.F. Li et al., Phys. Lett. B 695 (2011) 205, [4] S. Ando et al., Phys. Rev. D 81 (2010) 113006, [5] M.D. Campos et al., Phys. Rev. D 94 (2016) 095010

Wednesday, December 4, 2019 WHEPP XVI 5 Atmospheric(ATM) Neutrino  ATM neutrinos at Super Kamiokande (SK) experiment confirmed neutrino flavour oscillation – established the existence of neutrino masses and mixing

 Discovery of flavour oscillation of ATM neutrinos in 2015

 Cosmic ray particles collide with the nuclei in the Earth’s atmosphere, producing pions and kaons which decay into neutrinos

 First observations of ATM neutrinos in 1965 at kolar Gold experiment in India and simultaneously led by Fred Reines in South Africa – looking for proton decay – the discrepancy was resolved by the SK experiments

Wednesday, December 4, 2019 WHEPP XVI 6 ATM Neutrino  ATM – 1. Hyper Kamiokande – megaton-class water Cherenkov detector, fiducial volume ~ 20 times that of SK 2. ICAL detector at India-based Neutrino Observatory – 50 Kton magnetised iron calorimeter, charge identification efficiency 3. PINGU – low energy extension of IceCube 4. ORCA proposal – low energy extension of KM3NeT detector  Physics Goals - 1. and 2. 3. neutrino mass hierarchy 4. octant of 5. Non-standard interactions 6. probing 7. CPT violation studies

Wednesday, December 4, 2019 WHEPP XVI 7 PINGU (The Precision IceCube Next Generation Upgrade)  Low energy infill  17 strings × 125 sensors + Upgrade strings, 24m inter-string spacing  Effective mass – 6Mton ice  Energy threshold – few GeV  sample of over 60 000 atmospheric neutrinos per year  PINGU will make highly competitive measurements of parameters in an energy range over an order of magnitude higher than long- baseline neutrino beam experiments.  It is embedded within the IceCube DeepCore

Wednesday, December 4, 2019 WHEPP XVI 8 PINGU (DeepCore Topview)

Wednesday, December 4, 2019 WHEPP XVI 9 PINGU

Wednesday, December 4, 2019 WHEPP XVI 10 PINGU

Scientific Goals –  Augmenting the low-energy program of the upgrade. ~60k up-going atmospheric neutrinos per year  Neutrino mass ordering  appearance – test of the unitarity of (3 × 3) PMNS matrix  octant anomaly  Wide breadth of other science: 1. searches 2. Earth tomography 3. Supernovae Neutrinos (SN) 4...... Ref – M.G. Aartsen et al., JPG 44, 054006 (2017)

Wednesday, December 4, 2019 WHEPP XVI 11 High Energy  Neutrinos are an ideal messenger for astrophysics

 Neutrino telescope - 1. ANTARES and KM3NeT in the 2. GVD in Lake Baikal 3. IceCube buried in the ice of the South Pole

 Instrument a large volume of water or ice -> detect the ->consequence of a neutrino interaction with the detector

 IceCube contains 5160 DOMs within a volume of 1 km3

 Number of color points and their size - amount of light - relate to the energy of the incident neutrino

 Color code - >information about the timing -> reconstruct the direction of the produced -> estimate the position of the source

 Spatial distribution of the hits or rather the topology of the event - flavour of the neutrino

 Three neutrino sources - the , the supernovae SN1987A and the blazar TXS 0506 + 056

 High energy part of the astrophysical energy spectrum, extending from GeV to PeV energies

Wednesday, December 4, 2019 WHEPP XVI 12 IceCube Collaboration  In 2013, IceCube announced first detection of High energy astrophysical neutrinos - these events are called HESE events

 Recent HESE analysis- 7.5 years of icecube data with 103 neutrino events ( out of which 60 events are above 60 TeV)

 Best fit energy spectrum is a single power law with spectral index , all flavour flux Normalization

 In 2018, IceCube reported the first multi-messenger evidence of a flaring blazar in coincidence with the high energy neutrino event IC - 170922A

 A possible source candidate could be TXS 0506+056. 13 5 neutrino excess found in 2014-2015 over 110 days in addition to the event detected in 2017.

Wednesday, December 4, 2019 WHEPP XVI 13 IceCube

Probing a four flavour vis-a-vis three flavour neutrino mixing for ultrahigh energy neutrino signal at a 1 Km2 detector M. Pandey et al., Phys. Rev. D 97, 103015 (2018)

Wednesday, December 4, 2019 WHEPP XVI 14 From the analysis of the high-energy starting events (HESE) data (the IceCube Collaboration), they calculated a best fit power law for the neutrino flux as [ICRC2017 (2017) 981] .....2.....20) For a one component fit the neutrino flux , with the index We have computed for this flux as well and the energy range 60 TeV is to be considered for such calculations.

Table 2: Same as Table 1, but here we consider the diffuse flux of UHE neutrinos obtained from the recent analysis of the IceCube (HESE) data.

Figure 1: Variation of with and for (a) = 1◦ and (b) = 4◦ (the recent IceCube HESE data). IceCube

Mass and Life time of heavy dark matter decaying into IceCube PeV neutrinos M. Pandey et al., Phys. Lett. B 797, 134910 (2019)

Wednesday, December 4, 2019 WHEPP XVI 16 Introduction  The source of other UHE neutrino events at IceCube is by and large unknown. These also include the track events for the neutrinos in and around PeV region.  We explore an alternative possibility that these neutrinos could have been created by the rare or long lived decay of superheavy dark matter in the Universe.  The superheavy dark matter could be created during a spontaneous symmetry breaking in Grand Unified scale and thus they were never in thermal equilibrium with the Universe. Thus their production is nonthermal in nature. They can also be created by the process of gravitational production.  Here in this work, we consider the decay of the super heavy dark matter to interpret the neutrinos in and around the PeV region recorded by IceCube that includes the best fit region for muon neutrino track events given by IceCube in the same regime.  In the whole process one needs to consider two decay channels, one is the hadronic decay channel while the other is the leptonic decay channel.  We try to estimate the best fit value of the mass ( ) and the decay lifetime ( )of the dark matter, which undergoes a decay via the hadronic channel. Also for the fixed value of the dark matter mass we calculate the best fit value of the dark matter decay lifetime ( ) when both hadronic and leptonic channel are considered.

Wednesday, December 4, 2019 WHEPP XVI 17 IceCube IceCube Data and Fit [PoS(ICRC2017)981]

Wednesday, December 4, 2019 WHEPP XVI 18 Formalism [M. Pandey et al., Phys. Lett. B 797, 134910 (2019)] The neutrino spectrum from the decay of such dark matter can be written as ..... (1) where and the functions are taken from the reference [1]

...... (2)

is the dimensionless energy fraction transferred to the hadron. [1] S.R. Kelner et al., Phys. Rev. D 74, 034018 (2006); Erratum: Phys. Rev. D 79, 039901 (2009).

Wednesday, December 4, 2019 WHEPP XVI 19 Formalism [M. Pandey et al., Phys. Lett. B 797, 134910 (2019)] The neutrino flux can be of two type; extragalactic and galactic - The isotropic extragalactic neutrino flux from the decay of such a heavy dark matter with mass is given as ...... (3)

 Hubble radius  The cosmological dark matter density at the present epoch is  describes the neutrino energy spectrum, obtained from the decay of super heavy dark matter and this neutrino spectrum is a function of the neutrino energy at redshift

The galactic neutrino flux from similar decay is described by ..... (4)

 is the dark matter density and we consider Navarro-Frenk-White (NFW) profile.  defines the neutrino spectrum decaying from the super heavy dark matter , where , are the galactic coordinate . The total flux is obtained as ...... (5)

Wednesday, December 4, 2019 WHEPP XVI 20 Calculation and Results We have consider the UHE region in the energy range GeV to PeV.

[2]

[2] The IceCube Collaboration, 35th International Cosmic Ray Conference, ICRC2017, PoS ICRC2017 (2017) 981.

Ref - [M. Pandey et al., Phys. Lett. B 797, 134910 (2019)]

Wednesday, December 4, 2019 WHEPP XVI 21 Calculation and Results

Wednesday, December 4, 2019 WHEPP XVI 22 Calculations and Results The for our fit ...... (6), where

 is the number of chosen points (Table 1)  are the energies of the chosen points.  is the theoretical flux obtained from Eq. (5).  corresponding to experimental data are given in Table 1.  is the error of chosen experimental points (Table 1).

Figure

The best fit value is (only hadronic channel is considered for dark matter decay)

23 Wednesday, December 4, 2019 WHEPP XVI Calculations and Results

We make one parameter analysis (using Eq. (6) for all set of points given in Table 1) and obtained the best fit value of for the best fit value of (Figure 2) when both the hadronic and the leptonic channels are considered. The best fit value to be

Wednesday, December 4, 2019 WHEPP XVI 24 IceCube (arXiv:1909.06839)

Wednesday, December 4, 2019 WHEPP XVI 25 IceCube (arXiv:1911.10148)  Implication of the decay of SHDM on the aspect of matter- asymmetry.  Boltzmann-like equation needs to be solved to calculate the rate of baryon number production per decay [E.W. Kolb et al., AIP Proceedings, vol 484, pages 91-105]

 The amount of baryon asymmetry

 Baryon asymmetry is in the same ball park given by the PLANCK results [1807.06209]

Wednesday, December 4, 2019 WHEPP XVI 26 IceCube (what is new?)  Detection of tau neutrino candidate

 Long and thin Tracks - relativistic muon Single cascades- charge or neutral current interactions Double cascade - interaction of tau neutrino with the ice/water inside the detector

 One event among the events detected by IceCube was independently selected by three analyses and constitutes strong evidence for the first detection of a high energy tau neutrino [PoS(ICRC2019)016]

 Double cascade event with a deposited energy of 9 TeV in the first cascade and 80 TeV in the second and a distance of 17 m between them.  flavour ratio to the starting event sample, using the tau double cascade identifier, is 0.29:0.5:0.21

Wednesday, December 4, 2019 WHEPP XVI 27 ANTARES Telescope (Astronomy with a Neutrino Telescope and Abyss environmental RESearch)

 Monitoring one complete hemisphere of the sky –  Detect neutrinos emitted by transient astrophysical events  2.5 km under the Mediterranean Sea off the coast of Toulon,  Three cases are performed with the ANTARES telescope – 1. searches of neutrino candidates coincident with Swift and Fermi GRBs 2. IceCube high energy neutrino events 3. GW candidates observed by LIGO/Virgo  Offers – 1. study extreme physics 2. track some phenomena of the Universe – the birth of stellar mass black holes / mergers of the neutron star 3. probe distant regions of the Universe 4. identify candidate sources for multi-messenger astrophysics 5. also detect a mild excess of neutrino events in both track and cascade channels at a very high energy

Wednesday, December 4, 2019 WHEPP XVI 28 ANTARES Follow up of GWs –  LIGO - run 01 in 2015 - 3 GWs from BBH mergers – offline analysis by ANTARES

 Run 02 (Nov. 30, 2016 – August 25, 2017) – upgraded LIGO and VIRGO – GWs from 7 BBH mergers (plus 3 obtained in offline) and BNS inspiral GW170817 ANTARES try to see what is the potential neutrino counterpart of each of the alerts

 Run 03 (April 2019 – June 2019) – 17 alerts (14 confirmed astrophysical events + 3 retracted by LIGO/VIRGO – 14 events (=13 [11(BBHS) + 1(NSBH) + 1(BNS)] + 1 [BNS (terrestrial origin)] – In ANTARES out of these 13 events, 12 GW triggers have been performed. One trigger is not performed (GW error box too North for ANTARES)

Wednesday, December 4, 2019 WHEPP XVI 29 ANTARES Follow up of IceCube high energy –  2016 – HESE (high energy starting events), EHE (extremely high energy) events by the astrophysical multi-messenger observatory network – distributed to the community by GCN.

 In 2019 – IceCube provides two track event samples – 1. gold (with p>50%), 2. bronze (p>30%)

 Both IceCube and ANTARES – 1. their coincident detection would be a significant proof of the astrophysical origin 2. point directly to the position of the source in the sky

 Position is below the horizon of the ANTARES (yield to an up going events)

 Up to now – ANTARES received 27 triggers from IceCube – out of 27, 11 alerts has been followed 11 = 7(HESE) + 3 (EHE) +1 (gold) – rest of triggers either retracted by IceCube or in the wrong hemisphere.

Wednesday, December 4, 2019 WHEPP XVI 30 ANTARES

Follow up GRBs –  Transient astrophysical events – all over the EM spectrum

 Once a GRB is detected – alerts sent to ANTARES within 10 seconds via GCN

 2014 (starting year) up to now - 98 % of the alerts have been processed – 5 years operation 226 Swift and 536 Fermi GBN Bursts

 For a coincident neutrino detection, a dedicated offline analysis is running

 By simultaneously monitoring at least half of the sky and by its ability to reconstruct the events in real time, ANTARES is very well suited to detect transient sources Ref – POS (ICRC2019) 872

Wednesday, December 4, 2019 WHEPP XVI 31 KM3NeT (The Cubic Kilometre Neutrino Telescope)

 Under construction in the Mediterranean sea.  Two different modes -  1. ARCA (Astrophysical Research with Cosmic in the Abyss) – Capo Passero in Sicily 2. ORCA (Oscillation Research with Cosmic in the Abyss) – Close to ANTARES Telescope off Toulon, France  ARCA – searches for cosmic neutrino sources in TeV-PeV range  ORCA – 1. comparatively denser spacing of DOMs 2. optimized to detect GeV atmospheric neutrino 3. probe mass hierarchy 4. will be able to set competitive constraints on the GeV astrophysical flux.

 4 ORCA & 1 ARCA are now taking data (each string 18 DOMs with 9(36) m spacing in ORCA(ARCA) configuration.  Full completion in 2025 with 115 strings on the ORCA and 230 for ARCA.

Ref – arXiv: 1911.01719

Wednesday, December 4, 2019 WHEPP XVI 32 ANITA (Antarctic Impulse Transient Antenna)

 A balloon borne experiment - 1. 32 – 48 dual polarisation 2. altitude of 37 km 3. Horizon at 700 km 4. over 1 km3 ice visible

 Study UHE cosmic neutrinos by detecting the radio pulses emitted by their interactions with Antarctic ice sheet.

 High-energy cosmic neutrinos(1018 eV) result from interaction of UHE(1020 eV) cosmic rays with the photons of the CMBR.

 ANITA – Lite - 1. recorded about 113,000 3-fold coincident triggers. 2. set limits above 1018.5 eV to improve constraints. 3. demonstrates the power of the radio cherenkov technique applied to the balloon based observations to the Antarctic content

Wednesday, December 4, 2019 WHEPP XVI 33 ANITA

Wednesday, December 4, 2019 WHEPP XVI 34 DAMPE (DArk Matter Particle Explorer)  spectrum  Peak at 1.4 TeV, the other part of the spectrum can be explained by a broken power law with a spectral break at 0.9 TeV.  1.4 TeV excess – substantial excess and sharp, the excess is compared to the best continuum fit  Sources cannot be far away - sources of 1.4 TeV peak is most likely nearby source

Wednesday, December 4, 2019 WHEPP XVI 35 DAMPE  Possible Sources – 1. Isolated young Pulsar 2. Non astrophysical scenario – small dark matter substructure, such as a nearby clump

 Directionality problem – this can be resolved if the association in between and neutrino is established

 Existing ~ 8-year IceCube data is sufficient to test the excess is left handed and produced from the or decay of dark matter

Ref – Yue Zhao et al. , arXiv – 1712.03210[astro-ph]

Wednesday, December 4, 2019 WHEPP XVI 36 Suggestions  Constrain the parameters of superheavy dark matter (mass and lifetime) by doing the analysis of UHE neutrinos in and around EeV energy range at the ANITA .

 For = 0 , the muon to shower ratio can be calculated in 4 (3 active +1 sterile) flavour scenario for different fraction of events in the detector from each of the three different sources ( , ) Sources Flavour ratio at the sources neutron decay 1:0:0:0 pion decay 1:2:0:0 muon damped 0:1:0:0 Ref – A. Chatterjee et al., PRD 90, 073003 (2014); A.D. Banik, M. Pandey et al. PRD 97, 103015 (2018)  can be probed again for these sources in three flavour case using the similar approach Ref – W. Winter , PRD 74, 033015 (2006)  Antineutrino, Mass hierarchy can be studied by solar neutrino  Solar neutrino in KeV energy range can be probed in dark matter experiment

Wednesday, December 4, 2019 WHEPP XVI 37 THANK YOU

Wednesday, December 4, 2019 WHEPP XVI 38 Solar Neutrino

Wednesday, December 4, 2019 WHEPP XVI 39 Summary and Discussions  In this work, we have explored the possibility that the UHE neutrino detected by IceCube in and around PeV energy region could have originated from the decay of super heavy dark matter. We compute the neutrino spectrum from the heavy dark matter decay as prescribed in reference and obtained the galactic and extragalactic neutrino fluxes from such decays.  We then constrain the two unknown parameters namely the heavy dark matter mass and its decay lifetime by making a fit of the calculated neutrino flux with those given from the observed events at IceCube by the IceCube collaboration.  We first consider the hadronic channel for production from the heavy dark matter decay and our fit yield the best fit value for the parameters as We also furnish and C. L. contours in the parameter space  With this best fit value of we then add the contribution of the leptonic channel for this value of and then constrain the decay life time by performing the one parameter analysis.  From our studies it appears that in order to explain the nature of the neutrino flux for the upgoing muon events in and around PeV region by considering the decay of heavy dark matter to neutrinos, the dark matter mass should be of the order of undergoing the rare decays with life time .  For UHE neutrinos in and around PeV energy region, the hadronic channel suffices and the leptonic channel has very little role to play

Wednesday, December 4, 2019 WHEPP XVI 40 BACKUP SLIDES

Wednesday, December 4, 2019 WHEPP XVI 41 Formalism  Decay of super heavy dark matter to 1. QCD parton cascade (decaying to ) 2. Electroweak cascade (decaying mode consider)

 Neutrino Spectrum – Numerical evolution of DGLAP (Dokshitzer-Grivov-Lipatov-Altarelli-Parisi) equation [R. Aloisio et al. , PRD 69, 094023 (2004)]

Wednesday, December 4, 2019 WHEPP XVI 42 Wednesday, December 4, 2019 WHEPP XVI 43 Wednesday, December 4, 2019 WHEPP XVI 44