Olga Botner, Uppsala. Photo: Sven Lidström. Inspirationsdagar,

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1 Olga Botner, Uppsala Photo: Sven Lidström Inspirationsdagar,

2 OUTLINE OUTLINE WHY NEUTRINO ASTRONOMY? WHAT ARE NEUTRINOS? A CUBIC KILOMETER DETECTOR EXTRATERRESTRIAL NEUTRINOS WHAT NEXT? CONCLUSIONS LHC Neutriner från rymden fångade i Antarktis is / Olga Botner XX

3 Observation of the Sky, engraving in "Selenografia sive Lunae Descriptio", Johannes Hevelius 1647 Bibliotheque Nationale de France, Paris, France.

4 ASTRONOMY WITH PHOTONS optical astronomy pioneered by Ibn al-haytham El Basri (Alhazen) born c. 965 in present day Iraq traditional astronomy relies on capture of light in diverse ranges of the electromagnetic spectrum each tells a different story LHC? OPTICAL RADIO INFRARED X-RAY Crab nebula: SNR & pulsar ( Neutriner från rymden fångade i Antarktis is / Olga Botner

5 ASTRONOMY WITH PHOTONS according to quantum mechanics the basic unit (the quantum) of light is a photon at very high energies the universe is NOT transparent to photons! photons interact electromagnetically in the interior of stars with starlight with inter-stellar matter LHC with the CMBR AN ENERGY-DEPENDENT PHOTON HORIZON Neutriner från rymden fångade i Antarktis is / Olga Botner

6 γ-rays ( Mpc) Neutriner från rymden fångade i Antarktis is / Olga Botner

7 ENERGY SCALES OF THE UNIVERSE ZeV (Zeta)??? EeV (Exa) Active Galactic Nuclei Gamma Ray Bursts PeV (Peta) Supernova TeV (Tera) LIMIT OF HUMAN TECHNOLOGY Current Particle Accelerator 10 9 GeV (Giga) 10 6 MeV (Mega) Early accelerators 10 3 KeV (Kilo) Lab X-ray e 1 ev Battery 1 volt Neutriner från rymden fångade i Antarktis is/ Olga Botner Mar 2015 XX

8 COSMIC RAYS the Earth is bombarded by Cosmic Rays charged particles from outer space mostly protons (~90%) alphas (He nuclei, ~9%) heavier nuclei RADIO LHC LHC RADIO CMB VISIBLE γ-ray LIMITS CRs γ RAYS M. Turner&T. Ressell, Comments in Astrophys. 14 (1990) 323 discovered by Victor Hess 1912 Neutriner från rymden fångade i Antarktis is / Olga Botner

9 COSMIC RAYS 1912: Hess discovers CR ascends to 5000 m demonstrates that ionization increases from 1000m up - not natural radioactivity penetrating radiation from space 1938: Pierre Auger registers ~10 15 ev CR in the Alps, two cloud chambers ~1 km apart 1962: a ev CR registered Victor Hess, Nobel Prize 1936 Volcano Ranch giant detector array, New Mexico Neutriner från rymden fångade i Antarktis is / Olga Botner

10 COSMIC RAY SPECTRUM The highest observed energies in cosmic rays are to ev!! That is 50 Joule! Same energy as in a tennis ball hit by e.g. Björn Borg!! Knee 1 m -2 yr -1 a fast serve 68g at 200km/h ~100J What is accelerating these particles???? LHC Ankle 1 km -2 yr -1 Neutriner från rymden fångade i Antarktis is / Olga Botner

11 THE WORLDS MOST POWERFUL ACCELERATOR LHC AT CERN the Sun accelerates cosmic rays coronal mass ejection ev protons Neutriner från rymden fångade i Antarktis is / Olga Botner 11

12 THE LARGE HADRON COLLIDER circumference 27 km 100 m below the surface super conducting magnets (8 Tesla) proton beams max energy ev per beam moving at the speed of light at top energy LHC Neutriner från rymden fångade i Antarktis is / Olga Botner

13 Energy of an accelerator is proportional to radius times magnetic field What radius is needed to get ev when using LHC super conducting magnets? R P [GeV] = 0.3 B [T] R [m] LHC Neutriner från rymden fångade i Antarktis is / Olga Botner

14 km ~ the Earth distance to the Sun

15 Supernova remnants Active Galactic Nuclei Gamma Ray Bursts powered by gravitational energy realease Neutriner från rymden fångade i Antarktis is / Olga Botner

16 Cassiopeia A supernova remnant in X-rays shock fronts From F. Halzen acceleration when particles cross high magnetic fields

17 active galaxy particle flows near supermassive black hole Possible source of high-energy cosmic rays???

18 γ-rays ( Mpc) cosmic ray protons E < ev protons with E > ev interact with the cosmic microwave background (CMB) within 30 Mpc Neutriner från rymden fångade i Antarktis is / Olga Botner

19 NEUTRINO THE IDEAL MESSENGER FROM SPACE Moisey Markov Bruno Pontecorvo Neutriner från rymden fångade i Antarktis is / Olga Botner LHC M.Markov,1960: We propose to install detectors deep in a lake or in the sea and to determine the direction of charged particles with the help of Cherenkov radiation.

20 WHAT IS A NEUTRINO? postulated by Pauli in 1930 to ensure energy conservation in nuclear β decay Wolfgang Ernst Pauli ( ) was an Austrian-Swiss physicist, one of the pioneers of quantum physics, and recipient of the Nobel Prize for Physics in I have done a terrible thing, I have postulated a particle that cannot be detected. detecting the poltergeist, 1956 Neutriner från rymden fångade i Antarktis is / Olga Botner LHC Frederick Reines ( ), left, recipient of the Nobel Prize for Physics in 1995, and Clyde L. Cowan, Jr. ( )

21 WHAT IS A NEUTRINO? a fundamental matter particle electrically uncharged twin of the electron (and its cousins) tiny mass travels close to the velocity of light interacts only weakly (and gravitationally) MATTER ATOM ELECTRON NUCLEUS PROTON NEUTRON QUARKS THE NEUTRINO CAN GO THROUGH ENORMOUS AMOUNT OF MATTER WITHOUT BEING STOPPED. THREE LHC KINDS OF NEUTRINOS electron neutrino (ν e ) electron (e - ) muon neutrino (ν µ ) muon (µ - ) tau neutrino (ν τ ) tau (τ - ) Neutriner från rymden fångade i Antarktis is / Olga Botner

22 SOME NEUTRINO NUMBERS every second the Sun emits ( ) neutrinos from the nuclear reactions about neutrinos/cm 2 /second at Earth in the universe there are 330 million neutrinos per m 3 (energy ev) (but only ~ half a proton per m 3 ) 340 million neutrinos are created in your body every day due to 40 K decays when a Supernova explodes 99% of the energy is carried away by neutrinos! a solar neutrino will go through many light years of solid lead before it is stopped.. LHC Neutriner från rymden fångade i Antarktis is / Olga Botner

23 SOURCES OF ULTRA HIGH ENERGY COSMIC RAYS PRODUCE NEUTRINOS! γ-rays ( Mpc) neutrinos cosmic ray protons E < ev protons with E > ev interact with the cosmic microwave background (CMB) within 30 Mpc Neutriner från rymden fångade i Antarktis is / Olga Botner

24 SEEING THE NEUTRINO ν µ µ cascade shortlived particles the ν is detected by observing the charged particles created when it interacts with matter ν µ µ ν e e ν τ τ ν x ν x LHC Neutriner från rymden fångade i Antarktis is / Olga Botner

25 CHERENKOV RADIATION a shock front of Cherenkov light generated when a charged particle travels faster than light in a medium (ex. water or ice) CHERENKOV EFFECT 1 cos θ = β n β = v n( water) = c β =1 θ = 42 NASA's "Astronomy Picture of the Day" Archive optical sensors can capture LHC the Cherenkov radiation generated by the muon (electron, tauon) and map it Neutriner från rymden fångade i Antarktis is / Olga Botner

26 NEUTRINO DETECTION size of detector dependent on flux and interaction probability need large detectors: the more matter for the ν to interact with, the more interactions observed with time typical large tank filled with fluid Sudbury Neutrino Observatory, Canada 1000t D 2 O for detection of solar ν s (E ~ 10 7 ev) number of expected cosmic ν s (E > ev) decreases rapidly with increasing energy need HUGE instrumented volumes (~ 10 9 t) LHC DETECTOR MEDIUM ABUNDANT IN NATURE Neutriner från rymden fångade i Antarktis is / Olga Botner

27 Cherenkov light from a nuclear reactor Electrons with speeds higher to catch than the high-energy speed neutrinos need lots of material transparent to blue light of light in the water create the Cherenkov light in ice, blue light travels m Science day Malmö 27

28 the icecube project transforms a billion tons of ice into a neutrino detector

29 125 m Science day Malmö 29

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31 ICECUBE THE WORLD S LARGEST NEUTRINO OBSERVATORY 5160 DOM s in ice 1km 3 = 1 Gt instrumented volume started full operations in May 2011 electronics 20 Mt low-energy ext. threshold: 10 GeV PMT DIGITAL OPTICAL MODULE Neutriner från rymden fångade i Antarktis is / Olga Botner

32 hot water generators IceCube Site IceTop tanks drill tower 5 megawatt hot water drilling system

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34 start million pounds of cargo C-130 planes: > 50 flights LHC Neutriner från rymden fångade i Antarktis is / Olga Botner

35 2 days per hole 3.5 cm/second 35

36 Photo: Mark Krasberg two DOMs disappearing down the hole (water level ~ 50 m below surface). Neutriner från rymden fångade i Antarktis is / Olga Botner

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38 Neutriner från rymden fångade i Antarktis is / Olga Botner LHC

39 Recent results from IceCube / Olga Botner Jan

40 DATA COLLECTION WITH ICECUBE events collected since 2005 events selected by triggers server farm to preprocess & filter data ~ 100 GB/day sent North over satellite 2 WO scientists ensure uptime > 99% ~ 100 TB/y for science ~ 3000 atmospheric µ s/sec / year > 200 upgoing atm. ν s/day 10 5 / year estimated astrophysical ν s / year Neutriner från rymden fångade i Antarktis is / Olga Botner

41 Neutriner från rymden fångade i Antarktis is / Olga Botner

42 ICECUBE HIGH ENERGY NEUTRINOS two ways to identify high energy neutrinos look for up-going tracks Earth is used as a filter LHC look for events starting inside IceCube detector-based veto Neutriner från rymden fångade i Antarktis is / Olga Botner

43 HIGH-ENERGY NEUTRINO EVENTS neutrino induced muon entering IceCube from below LHC TWO neutrino events starting in IceCube color code: early times - RED Neutriner från rymden fångade i Antarktis is / Olga Botner

44 LOOKING FOR A NEEDLE IN A HAYSTACK for each muon from a neutrino reaction there is ~ a million muons from cosmic ray reactions in the atmosphere these background muons penetrate through the ice down to the detector atmospheric µ rate ~ 10 3 Hz atmospheric ν rate ~ 10-3 Hz ASTROPHYSICAL ν rate ~ 10-6 Hz LHC REDUCE BACKGROUNDS BY REQUIRING VERY HIGH ENERGY EVENTS! Neutriner från rymden fångade i Antarktis is / Olga Botner

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52 BREAKTHROUGH DETECTION OF A FLUX OF ASTROPHYSICAL ν S Bert 1.04 PeV Aug Ernie 1.14 PeV Jan Big Bird 2 PeV Dec the highest energy ν s ever observed 10 6 x higher energies than Solar ν s starting event analysis dominated by cascades ~ 50% atmospheric background 28 events/2 yrs (2013) 54 events/4 yrs (2014) isotropic directions, probably from many extragalactic sources Neutriner från rymden fångade i Antarktis is / Olga Botner

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54 ASTROPHYSICAL ν S CONFIRMATION! flux of muon neutrinos through the Earth neutrinos of all flavors interacting inside IceCube Neutriner från rymden fångade i Antarktis is / Olga Botner

55 HIGH ENERGY STARTING EVENTS SKYMAP compatible with isotropy shower events only p-value = 7.2 % too few events to identify sources [IceCube PRL 113 (2014)] ~ 40% of the events are expected to originate in the atmosphere (bckg) Neutriner från rymden fångade i Antarktis is / Olga Botner

56 LHC [Slide: Markus Ahlers NeuTel2015] Neutriner från rymden fångade i Antarktis is / Olga Botner

57 NEUTRINO STARS? to look for neutrino stars need more events search for clustering decrease the energy threshold atmospheric ν s dominate atmospheric µ s dominate LHC equatorial skymap ~ events [Astrophys.J. 732 (2011) 18] Neutriner från rymden fångade i Antarktis is / Olga Botner

58 FUTURE ICECUBE-GEN2 HIGH-ENERGY ALTERNATIVE BUILD A LARGER DETECTOR Opening the Southern sky with a surface veto! Neutriner från rymden fångade i Antarktis is / Olga Botner

59 OUTLINE CONCLUSIONS a new window to the universe has been cracked open IceCube has observed a flux of neutrinos from cosmos but where are the neutrino stars? need more data at high energy Sweden is at the forefront of this research LHC Neutriner från rymden fångade i Antarktis is / Olga Botner XX

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