HEP2014, 8-10 May, Naxos, Greece G.K. Fanourakis IAXO: A Swiss knife for the … Dark Sector Exploration George K. Fanourakis Institute of Nuclear and Particle Physics NCSR ‘Demokritos’ National Center for Science Research ‘Demokritos’ Institute of Nuclear & Particle Physics

HEP2014, 8-10 May, Naxos, Greece G.K. Fanourakis Dark Matter, Dark Energy, The make-up of the Universe Experiments to search for dark matter and dark energy IAXO: the future of the dark sector research IAXO instrumentation Towards a TDR Conclusions The menu

HEP2014, 8-10 May, Naxos, Greece G.K. Fanourakis The rotation curves of stars in the Milky Way, and galaxies in clusters Gravitational lensing Mass in the intergalactic space The bullet cluster The rotation curves of stars in the Milky Way, and galaxies in clusters Gravitational lensing Mass in the intergalactic space The bullet cluster Dark Matter

HEP2014, 8-10 May, Naxos, Greece G.K. Fanourakis The dark energy and the accelerating expansion of the Universe The dark energy and the accelerating expansion of the Universe We initially believed that the universe is expanding with a decelerating rate, because of gravity. However, in 1998 it was proven that there is an unexpected acceleration of expansion.

HEP2014, 8-10 May, Naxos, Greece G.K. Fanourakis The most detailed map ever created of the cosmic microwave background – the relic radiation from the Big Bang. PLANCK: an ESA space observatory To measure the anisotropy of the Cosmic Microwave Background (CΜB)

HEP2014, 8-10 May, Naxos, Greece G.K. Fanourakis The cosmic Standard Model ΛCDM

HEP2014, 8-10 May, Naxos, Greece G.K. Fanourakis The make-up of the Universe ESA – Planck 2013

HEP2014, 8-10 May, Naxos, Greece G.K. Fanourakis WIMPs (Weakly Interacting Massive Particles) such as the lightest supersymmetric particles (e.g neutralino) and others (e.g. the lightest Kaluza-Klein particle) WIMPs (Weakly Interacting Massive Particles) such as the lightest supersymmetric particles (e.g neutralino) and others (e.g. the lightest Kaluza-Klein particle) Axions, particles invented to solve the Strong CP Problem of the Strong Interactions. They are stable thus Dark Matter candidates Dark Matter candidates Supersymmetric particles are expected at the LHC (…still) In the meanwhile … unusually many experiments have been looking for WIMPS The existence of axions is being investigated in a few experiments in Europe, USA and Japan.

HEP2014, 8-10 May, Naxos, Greece G.K. Fanourakis 9 §Axion-photon coupling present in every model. This is the most relevant of axion properties. Axion detection strategies are mostly based on the axion-photon coupling Axion-photon conversion in the presence of an electromagnetic field (Primakoff effect) Axion-photon conversion in the presence of an electromagnetic field (Primakoff effect) Axion phenomenology

HEP2014, 8-10 May, Naxos, Greece G.K. Fanourakis Axion Cosmology Axion, the most famous member of WISPs (Weakly Interacting Sub- eV Particles or Slim Particles), is not only the explanation to the smallness of the CP violation in strong interactions but is also a prime candidate for the Dark Matter of the Universe. Axion like Particles (ALPs) such as light spin 1 hidden sector photons and minicharged particles seem to occur in string theories, Does any of these light particles exist? WISPs explain the fact that Very High Energy gamma rays are being observed, and the properties of white dwarfs. Searching for WISPs should be intensified

HEP2014, 8-10 May, Naxos, Greece G.K. Fanourakis Axions are produced in the Sun’s core via the Primakoff mechanism. They travel to earth where they are converted to X-rays in a strong transverse magnetic field via the inverse Primakoff mechanism. Axion Helioscopes - Principle

HEP2014, 8-10 May, Naxos, Greece G.K. Fanourakis Magnetic field: B = 9T Length: L = 10m Detectors for sunrise X-rays: Micromegas CCDs + focusing telescope Detectors for sunset X-rays: Micromegas The CAST experiment Expected flux

HEP2014, 8-10 May, Naxos, Greece G.K. Fanourakis ADMX detects the very weak conversion of dark matter axions into microwave photons (technique proposed by Sikivie,1983). Axion conversion into photons is stimulated by an apparatus consisting of an 8 tesla magnet and a cryogenically cooled high-Q tunable microwave cavity. When the cavity's resonant frequency is tuned to the axion mass, the interaction between nearby axions in the Milky Way halo and ADMX's magnetic field is enhanced. This results in the deposit of a very tiny amount of power (less than a yoctowatt, W) into the cavity. Signals from the cavity are amplified by an exotic cryogenic Superconducting QUantum Interference Device (SQUID) amplifier followed by ultralow noise cryogenic HFET amplifiers. Detecting relic axions in RF cavities (ADMX Haloscope) Detecting relic axions in RF cavities (ADMX Haloscope)

HEP2014, 8-10 May, Naxos, Greece G.K. Fanourakis When linearly polarized light enters a birefringent medium such as the polarization is 45 degrees wrt the magnetic filed, the two components of this vector (one parallel and one transverse to the field) will propagate with different velocity and they will result out-of-phase. The light will exit the medium and its polarization will turn from linear to elliptic. This causes retardation of the real photon  ellipticity. This causes loss of photons in the beam  dichroism. virtual production real production Laser Experiments: PVLAS

HEP2014, 8-10 May, Naxos, Greece G.K. Fanourakis Laser Experiments: Light shining through a wall (ALPS) A high power laser beam goes through a strong transverse magnetic field and falls into a wall. The photons interact with the magnetic filed an produce axions. The axions penetrate the wall ! A second strong magnetic filed converts back the axions to photons. It seems as if the laser beam penetrates the wall !

HEP2014, 8-10 May, Naxos, Greece G.K. Fanourakis Chameleon Particles (DM-DE) Chameleons are particles with non-linear interactions. Their mass depends on the environment !!! When in the intergalactic space they have very little mass (which makes them o good candidate for dark matter). When they are in the lab they have a large mass – thus difficult to detect. They interact with the SM particles via the 5 th force, which is negligible in the lab but considerable in the intergalactic space, thus they may be responsible for the cosmic acceleration. They are being sought in various experiments…

HEP2014, 8-10 May, Naxos, Greece G.K. Fanourakis The GammeV-CHASE experiment Photons traversing a strong magnetic field convert to chameleons The laser beam is turned off and photon detectors are energized to look for the photons coming from chameleons converting back to photons a)a) b)b)

HEP2014, 8-10 May, Naxos, Greece G.K. Fanourakis The 4 th generation axion experiment ΙΑΧΟ (International AXion Observatory) The 4 th generation axion experiment ΙΑΧΟ (International AXion Observatory) The future in the search for Dark Matter and Dark Energy, the successor of CAST

HEP2014, 8-10 May, Naxos, Greece G.K. Fanourakis IAXO Letter of Intent: CERN-SPSC signatures / 38 institutions IAXO Conceptual Design: accepted in JINST (arXiv: ) IAXO Letter of Intent: CERN-SPSC signatures / 38 institutions IAXO Conceptual Design: accepted in JINST (arXiv: )

HEP2014, 8-10 May, Naxos, Greece G.K. Fanourakis Sensitivity goal: >4 orders of magnitude improvement in signal- to-noise ratio wrt CAST. (>1 order of magnitude in sensitivity of g a  ) IAXO – Concept §No technological challenge (build on CAST experience) l New dedicated superconducting magnet, built for IAXO (improve >300 B 2 L 2 A f.o.m wrt CAST) l Extensive (cost-effective) use x-ray focalization over ~m 2 area. l Low background detectors (lower 1-2 order of magnitude CAST levels) Enhanced axion helioscope: JCAP 1106:013,

HEP2014, 8-10 May, Naxos, Greece G.K. Fanourakis IAXO – Conceptual Design §Large toroidal 8-coil magnet, L = ~20 m, 5-6 Tesla §8 bores: 600 mm diameter each §8 x-ray optics + 8 detection systems §Rotating platform with services §Tracking 12 hours/day 21

HEP2014, 8-10 May, Naxos, Greece G.K. Fanourakis IAXO magnet TOROIDAL CONFIGURATION specifically built for axion physics TOROIDAL CONFIGURATION specifically built for axion physics Each conversion bore (between coils) 600 mm diameter Each conversion bore (between coils) 600 mm diameter Cryostat Cold mass Bores go through cryostat Magnetic length 20 m Total cryostat length 25 m

HEP2014, 8-10 May, Naxos, Greece G.K. Fanourakis IAXO x-ray optics X-rays are focused by means of grazing angle reflection (usually 2) Many techniques developed in the x-ray astronomy field. But usually costly due to exquisite imaging requirements Focal length ABRIXAS spare telescope, in use in one of the 4 bores of CAST (pioneer use of x-ray optics in axion research) 23

HEP2014, 8-10 May, Naxos, Greece G.K. Fanourakis IAXO x-ray optics Each bore equipped with an x-ray optics focusing to 0.2 cm 2 Exquisite imaging not required BUT need cost-effective way to build 8 (+1 spare) optics of 600 mm diameter each Use NuSTAR satellite mission technologie 24

HEP2014, 8-10 May, Naxos, Greece G.K. Fanourakis IAXO low background detectors 8 detector systems Small gas chamber with Micromegas readouts for low-background x-ray detection Shielding 25

HEP2014, 8-10 May, Naxos, Greece G.K. Fanourakis IAXO low background detectors Small Micromegas-TPC chambers: Shielding Radiopure components Offline discrimination Goal background level for IAXO: – c keV -1 cm -2 s -1 Already demonstrated: ~8×10 -7 c keV -1 cm -2 s -1 (CAST 2013 result) c keV -1 cm -2 s -1 (underground at Canfranc) Active program of development. Clear roadmap for improvement. History of background improvement of Micromegas detectors at CAST Nominal values at CAST Values underground (Canfranc) Latest CAST SSMM 2013 levels IAXO goals See arXiv:

HEP2014, 8-10 May, Naxos, Greece G.K. Fanourakis IAXO low background detectors Optics + detector pathfinder system in CAST IAXO optics+detector joint system Newly designed MM detector (following IAXO CDR) New x-ray optics fabricated following technique proposed for IAXO (but much smaller, adapted to CAST bore) It will take data in CAST in 2014 First time low background + focusing in the same system Very important operative experience for IAXO Detector installed at CAST this year. New optics coming beginning of

HEP2014, 8-10 May, Naxos, Greece G.K. Fanourakis A low mass microbulk with real x-y strips structure Under development (T. Geralis talk) 28 NCSR Demokritos (coordinator) IRFU Saclay Univ. of Zaragoza CERN Aim of the project  To develop microbulk Micromegas detectors with segmented mesh Motivation Real x-y structure Mass minimization Production Simplification Low background, low threshold detectors X- strips Y- strips 1 st batch produced at CERN

HEP2014, 8-10 May, Naxos, Greece G.K. Fanourakis IAXO sensitivity prospects Astrophysical hints for ALPs IAXO in the high mass end, and future phases of ADMX in the low mass end will explore large part of the QCD axion model region in the next decade. Much larger QCD axion region explored 29

HEP2014, 8-10 May, Naxos, Greece G.K. Fanourakis Additional IAXO physics cases  IAXO sensitivity to BCA solar axion with values of g ae of relevance §More specific ALP or WISP (weakly interacting slim particle) models. could be searched for at the low energy frontier of particle physics: l Paraphotons / hidden photons l Chameleons l Non-standard scenarios of axion production §Microwave LSW setup §Use of microwave cavities or dish antennas, dark matter halo axions could be searched for  next slide §IAXO as “generic axion/ALP facility” 30 Possible additional technologies to push E thresholds down: GridPix TES Low-noise CCDs Possible additional technologies to push E thresholds down: GridPix TES Low-noise CCDs See arXiv: (F. Caspers /CERN) See arXiv: (F. Caspers /CERN)

HEP2014, 8-10 May, Naxos, Greece G.K. Fanourakis IAXO-DM configurations? §Prospects under study. Very motivated (encouraged by CERN SPSC) §Needed new know-how (cavities, low noise microwave detectors…) §Various possible arrangements in IAXO. Profit the huge magnetic volume available: 1. Single large cavity tuned to low masses 2. Thin long cavities tuned to mid-high masses. Possibility for directionality. Add several coherently? 3. Dish antenna focusing photons to the center. Not tuned. Broadband search. Competitive at higher masses? 31

HEP2014, 8-10 May, Naxos, Greece G.K. Fanourakis IAXO timeline 32 ~18 months -> TDR + preparatory activities ~3.5 years construction ~2.5 years integration + commissioning

HEP2014, 8-10 May, Naxos, Greece G.K. Fanourakis IAXO costs 33 Laboratory engineering, maintenance & operation and physics exploitation not included

HEP2014, 8-10 May, Naxos, Greece G.K. Fanourakis IAXO in astroparticle roadmaps 34 §ASPERA/APPEC Roadmap acknowledges axion physics, CAST, and recommends progress towards IAXO. §Important community input in the European Strategy for Particle Physics §Presence in the Briefing Book of the ESPP, which reflects also APPEC roadmap recommendations. §ESPP recomends CERN to follow APPEC recomendatons. §Important effort in relation with US roadmapping (Snowmass, and P5 process). Snowmass reports speak very favourably of axion physics and IAXO. C. Spiering, ESPP Krakow

HEP2014, 8-10 May, Naxos, Greece G.K. Fanourakis IAXO status of project 35 §2011: First studies concluded (JCAP 1106:013,2011) §2013: Conceptual Design finished (arXiv: ). l Most activity carried out up to now ancillary to other group’s projects (e.g. CAST) §August 2013: Letter of Intent submitted to the CERN SPSC l LoI: [CERN-SPSC ] l Presentation in the open session in October 2013: §January 2014: Positive recommendations from SPSC. §2014: Transition phase: In order to continue with TDR & preparatory activities, formal endorsement & resources needed. l Some IAXO preparatory activity already going on as part of CAST near term program. l Preparation of a MoU to carry out TDR work.

HEP2014, 8-10 May, Naxos, Greece G.K. Fanourakis Conclusions 36 §CAST has been a very important milestone in axion research during the last decade l 1 st CAST limits most cited exp. axion paper l Largest effort/collaboration in axion physics so far §IAXO, a forth generation axion helioscope, natural and timely large- scale step to come now. §A clear high level baseline physics case. IAXO can probe deep into unexplored axion + ALP parameter space. l But also several additional physics cases. Possibility to host relic axion searches in the future. §No technological challenge. All enabling technologies exist §Investment effort at the level of Next Generation DM experiments under consideration in the astroparticle community §LoI to CERN recently proposed. Positive answer from SPSC. MoU to start TDR under preparation. §IAXO could become next large project & a “generic axion facility” with discovery potential in the next decade.

HEP2014, 8-10 May, Naxos, Greece G.K. Fanourakis IAXO is a powerful new tool to investigate the Dark Sector